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HYGIENE 

AND 

PUBLIC    HEALTH 

VOL.  I. 


A     TEEATISE 


ON 


HYGIENE  MD  PUBLIC  HEALTH 


EDITED     BY 

THOMAS   STEVENSON,   M.D.,  F.E.C.P.  Lond. 

LECTUBEE   ON   CHEMISTBY  AND   ON   MEDICAL   JUBISPETJDENCE 

AT   guy's   hospital 

OFFICIAL   ANALYST   TO    THE    HOME    OFFICE 

AND 

SHIELEY    F.   MUEPHY 

MEDICAL   OFFICER   OF   HEALTH   OF   THE  ADMINISTEATIVE   COUNTY  OF   LONDON 


VOL.  I. 


PHILADELPHIA 

P.    BLAKISTON,    SON,    &    CO. 

1012    WALNUT    STKEET 
1892 


PEEFACB 


It  is  now  some  years  since  the  late  Professor  De  Chaumont  proposed  to 
the  pubHshers  of  this  work  the  issue  of  a  treatise  on  Hygiene  and  Public 
Health  which  should  contain  essays  by  various  authors  especially 
qualified  to  discuss  the  several  subjects  which  come  within  its  scope. 

The  wisdom  of  adopting  this  course  has  been  increasingly  demon- 
strated as  time  has  given  opportunity  for  knowledge  to  grow ;  for  in 
some  degree  these  subjects  have  become  specialised,  and  as  a  result 
exceptional  knowledge  and  experience  of  each  are  required  for  their 
proper  treatment. 

The  Editors,  in  superintending  the  preparation  of  these  volumes, 
have  been  fortunate  in  obtaining  the  co-operation  of  writers  whose 
names  are  the  best  guarantee  of  the  value  of  their  contributions. 

The  work  has  been  divided  into  different  sections,  each  of  which 
is  independent  of  the  others ;  but,  inasmuch  as  numerous  authors 
have  been  employed  in  its  elaboration,  and  one  subject  is  often  related 
to  another,  it  has  not  always  been  found  possible,  without  destroying 
the  completeness  of  an  article,  to  avoid  dealing  in  it  with  matters  also 
treated  by  another  writer.  In  a  few  minor  instances  the  views  upon 
the  same  subject  by  different  authors  have  not  always  been  fully  in 
accord. 

It  has,  however,  been  thought  that  it  would  be  better  in  a  work 
consisting  of  articles  to  each  of  which  the  author's  name  is  appended, 
to  allow  of  some  freedom  in  this  respect,  rather  than  to  endeavour  to 
bring  occasionally  divergent  views  into  harmony,  especially  when  the 
data  to  hand  do  not  afford  grounds  for  complete  judgment. 

The  several  articles  consequently  do  not  necessarily  represent  the 
views  of  the  Editors ;  each  author  is  separately  responsible  for  those 
he  expresses,  the  work  of  the  Editors  being  more  particularly  directed 
to  ensuring  a  convenient  arrangement  of  the  subjects. 

In  the  selection  of  subjects  the  Editors  have  been  mainly  guided 
by  the  requirements  of  the  Medical  Officer  of  Health  at  the  present 
time,  after  a  lapse  of  more  than  forty  years  since  this  office  was  created. 
The  earliest  conceptions  of  the  Medical  Officer  of  Health  showed  that 
he  was  expected  to  be  no  mere  empiricist.  So  long  ago  as  the  year 
1848  an  instructional  minute  of  the  General  Board  of  Health  required 


vi  HYGIENE 

that  he  should  make  himself  familiar  with  the  natural  and  acquired 
featui'es  of  the  place  to  which  he  was  appointed  ;  with  the  levels,  inclina- 
tions, soil,  wells,  and  water  springs  of  the  district;  with  its  meteorological 
peculiarities ;  with  the  distribution  of  its  buildings  and  open  spaces, 
and  of  its  burial-grounds ;  with  its  drainage ;  with  its  industries ; 
with  the  house  accommodation  of  the  poorer  classes  and  their  oppor- 
tunities for  personal  cleanliness  ;  and  with  the  regulations  in  force  for 
lodging-houses-  and  slaughtering-places,  for  the  cleansing  of  the  place, 
and  for  the  removal  of  domestic  refuse.  He  was  also  to  obtain  infor- 
mation as  to  disease  prevalence,  and  as  to  the  extent  of  its  dependence 
upon  removable  causes. 

It  was  held  that  for  the  proper  performance  of  his  duties  he  was  to 
be  skilled  in  pathology,  because  this  science  implied  an  exact  study  of 
the  causes  of  disease  in  their  relations  to  the  living  body.  A  know- 
ledge of  vital  statistics  was  held  to  be  necessary  for  the  purpose  of 
enabling  proper  comparison  to  be  made  which  would  give  evidence  of 
the  effect  of  various  conditions  on  the  population.  He  was  to  be  skilled 
in  chemistry  and  the  use  of  the  microscope  for  the  purpose  of  judging 
of  the  impurities  of  air,  earth,  and  food,  and  his  chemistry  was  to 
help  him  in  the  application  of  deodorising  and  disinfecting  agents. 
And  natural  philosophy  was  to  aid  him  in  its  relation  to  ventilation 
and  atmospheric  changes,  and  with  reference  also  to  manufacturing 
processes  alleged  to  be  hurtful  to  health. 

The  experience  of  the  time  which  has  elapsed  since  this  minute  was 
issued  bears  witness  to  the  wisdom  of  its  authors.  The  subject-matter 
which  now  comes  within  the  province  of  the  Medical  Officer  of  Health 
is  mainly  an  amplification  of  that  of  which  the  minute  gives  account. 

With  the  '  more  exact  study  of  the  causes  of  disease '  has  grown 
the  science  of  preventive  medicine,  of  which  the  basis  is  a  knowledge 
of  the  natural  history  of  disease.  The  investigation  of  the  causes  of 
disease  has  now  for  a  number  of  years  been  prosecuted  in  the  labora- 
tory as  well  as  in  the  field  by  many  capable  observers  both  in  this 
country  and  abroad. 

In  this  way  there  has  already  been  established  the  intimate  rela- 
tion of  micro-organisms  to  communicable  maladies,  and  certainly  for 
each  of  certain  diseases  it  has  been  definitely  shown  that  a  particulate 
organism  is  the  cause.  Again,  it  has  been  learnt  that  other  animals 
than  man  may  serve  as  the  hosts  of  these  organisms,  and  hence,  in 
seeking  for  the  source  of  disease  of  this  sort  in  the  human  subject,  the 
inquirer  is  led  to  study  disease  in  the  lower  animals.  Man  in  his 
domestication  of  animals,  and  in  his  use  of  their  flesh  and  products 
as  his  food,  is  exposed  to  invasion  by  diseases  from  which  they  and  he 
alike  can  suffer. 

Coincident  with  efforts  to  become  acquainted  with  the  ultimate 
cause  of  communicable  diseases,  the  study  of  the  natural  history  of 
these  maladies  has  been  diligently  pursued.  Fresh  facts  have  been 
learnt  concerning  their  beginnings  and  the  methods  of  their  dissemina- 


PREFACE  vii 

tion,  of  the  effects  upon  their  prevalence  of  the  aggregation  of  children 
in  schools,  of  the  advantages  and  disadvantages  attendant  upon  the 
isolation  of  persons  suffering  from  them  in  hospitals,  and  concerning 
a  variety  of  other  circumstances  respecting  them  which,  for  the  pur- 
poses of  their  prevention,  it  is  important  should  be  known. 

The  part  played  by  earth,  air,  and  water  in  connection  with  disease 
in  man  is  now  better  understood,  and  particularly  as  a  result  of  the 
work  of  the  last  few  years.  The  general  notions  that  filth  pla.yed  an 
active  part  as  a  producer  of  disease  are  being  replaced  by  a  more  pre- 
cise knowledge  of  the  particular  maladies  that  are  encouraged  thereby, 
and  of  the  circumstances  under  which  filth  can  itself  conserve  and 
foster  the  specific  entities  which  are  the  essential  causes  of  certain  of 
these  affections.  Moreover,  the  physical  conditions  which  give  oppor- 
tunity for  these  influences  to  exert  a  destructive  power  are  becoming 
more  accurately  determined,  and  hence  the  work  of  the  health  authority 
is  ripening  into  the  application  of  definite  knowledge  for  the  preserva- 
tion of  the  community. 

The  ability  of  populations  to  protect  themselves  from  preventable 
disease  is  necessarily  in  some  degree  dependent  upon  economic  con- 
siderations. Earlier  efforts  have  been  inevitably  tentative,  and  as  a 
result  there  exists  a  not  unnatural  desire  on  the  part  of  representative 
bodies  to  postpone  taking  a  costly  procedure  until  the  course  which  may 
be  best  adopted  is  well  defined.  Nevertheless,  as  the  result  of  the  efforts 
of  more  enterprising  communities,  there  is  accumulation  of  valuable 
experience  in  reference  to  such  questions  as  methods  of  conservancy, 
water  supply,  the  arrangements  of  streets  and  houses,  which  are  ready 
to  be  utilised  by  the  Health  Ofi&cer  in  advising  the  authority  he  serves. 

Although  the  lessons  learned  by  the  investigator  are  not  always 
immediately  applicable  for  the  day  by  day  administration  of  the  Sanitary 
Authority,  nevertheless  they  provide  a  basis  for  further  inquiry  by 
those  employed  in  the  public  service,  and  indicate  the  points  which 
they  should  observe  in  their  examination  of  the  phenomena  which 
are  constantly  before  them.  And  beyond  all  question  the  results 
hitherto  gained  give  ample  guarantee  of  the  value,  and  mdeed  of  the 
necessity,  of  the  acquisition  of  knowledge  for  guiding  communities  in 
their  control  of  individual  action. 

The  coincidence  of  the  enforcement  of  the  public  health  law  and 
the  reduction  of  the  general  death-rate,  as  demonstrated  by  the  valuable 
records  of  the  statistical  department  of  the  State,  suffices  for  the 
encouragement  of  sanitary  authorities  in  perseverance  in  the  duties 
which  devolve  upon  them,  and  indeed  demand  from  them  the  removal 
of  conditions  which  have  been  found  to  be  in  a  special  sense  habitually 
related  to  the  causation  of  particular  diseases. 

As  the  public  mind  has  become  possessed  by  the  consideration  that 
disease  is  largely  preventable,  the  claim  tends  to  be  more  fully  recog- 
nised that  the  community  should  possess  the  right  to  regulate  the 
action  of  the  individual  in   the   interest  of  the  loublic   health.     In 


viii  HYGIENE 

earlier  years  such  a  claim  was  regarded  with  some  distrust  and  even 
with  dissatisfaction  ;  at  the  present  time,  however,  the  attitude  of  the 
public  towards  health  administration  is  very  different,  and  successive 
Parliaments  have  conferred  on  sanitary  authorities  additional  powers 
for  the  control  of  .conditions  prejudicial  to  health,  even  to  the  extent 
of  placing  under  exceptional  circumstances  a  limitation  on  personal 
liberty.  The  English  Law  of  Public  Health  has,  moreover,  become 
the  basis  of  colonial  and  foreign  legislation,  and  is  necessarily  subject- 
matter  with  which  the  Health  Officer  must  make  himself  intimately 
acquainted. 

It  has  been  the  desire  of  the  Editors  that  the  several  papers  which 
these  volumes  contain  should  present  for  the  use  of  readers  a  fair 
account  of  the  knowledge,  so  far  as  obtainable,  of  the  subjects  of  which 
they  treat.  These  subjects  are  in  the  main  those  which  are  usually 
dealt  with  in  similar  works,  but  in  the  selection  of  authors  it  has  been 
thought  well  not  to  limit  the  choice  to  members  of  the  medical  profes- 
sion. Thus,  while  air  has  been  treated  by  the  physician,  warming  and 
ventilation  have  been  entrusted  to  the  physicist ;  again,  climate  has 
been  discussed  by  the  physician,  and  meteorology  has  been  allotted  to 
the  meteorologist ;  and  again,  the  article  on  the  dwelling  has  been  con- 
tributed by  members  of  the  architectural  profession,  while  the  surgeon 
has  undertaken  the  discussion  of  hospital  hygiene.  In  addition  to 
the  subjects  heretofore  contained  in  works  on  Hygiene,  it  has  been 
thought  desirable  to  give  equal  prominence  to  some  others  which  have 
become  now  of  not  less  concern  to  the  Health  Officer.  Systematic 
Physical  Education,  which  has  long  been  neglected  in  this  country, 
is  now  receiving  more  attention,  and  the  need  for  its  recognition  as 
part  of  every  educational  system  is  generally  accepted,  and  hence  a 
section  has  been  devoted  to  its  discussion.  A  separate  section  has 
also  been  devoted  to  the  discussion  of  EngHsh  Sanitary  Law.  The 
pathology  and  etiology  of  infectious  diseases  have  necessarily,  in  view 
of  the  immense  advance  lately  gained  in  these  subjects,  appeared  to 
deserve  an  especial  place  in  a  work  which  gives  account  of  preventable 
disease.  Accordingly,  in  order  to  make  this  section  self-contained, 
and  to  obviate  the  necessity  of  the  reader  seeking  elsewhere  explana- 
tion of  the  matter  he  is  studying,  it  has  been  considered  necessary 
that  it  should  give  some  account  of  bacteriology  and  the  methods  of 
examination  of  micro-organisms.  Further,  with  a  view  to  making  the 
account  of  this  class  of  malady  fairly  complete,  a  section  has  been 
added  on  the  Natural  History  and  Prevention  of  Infectious  Diseases. 


CONTENTS 


OF 


THE    FIEST    VOLUME 


AIE  .  .......  J.  Lane  Hotter 

WAEMING  AND   VENTILATION         .         .         .  W.  N.  Shaio  . 

METEOROLOGY '  .         .G.J.  Syinons 

INFLUENCE   OF   CLIMATE    ON   HEALTH        .  C.  Theodore  Williams 

WATER Thomas  Stevenson . 

THE   INFLUENCE   OF   SOIL   ON   HEALTH      .  S.  Monckton  Copevian 

FOOD Sidney  H.  C.  Martin 

THE   INSPECTION   OF    MEAT    .         .         .         .  E.  W.  Hope    . 

CLOTHING      .     ■ Geo.  Vivian  Poore  . 

PHYSICAL   EDUCATION       .         .        .         .         .  Frederick  Treves    . 

BATHS ; .         .        .  W.  Hale  White 

THE   DWELLING 

HOSPITAL   HYGIENE 

THE   DISPOSAL   OF   REFUSE    . 

OFFENSIVE   AND   NOXIOUS   BUSINESSES     .  Thomas  Whiteside  Hime 

SLAUGHTER-HOUSES E.  W.  Hope    . 


P.  Gordon  Smith  and  Keith] 
D.  Young    ...       J 

H.  G.  Hoivse  .... 


lorfield  and  Louis'] 
■kes    ...       J 


W.  H.  Corfield  and  Louis' 
C.  Park, 


VAdT. 
1 

31 
149 

185 
223 
307 
391 
493 
507 
537 
615 

r,49 

777 
805 
897 
975 


INDEX 


993 


VOL.  I. 


PLATES   IN   VOL.  I 


PLATE 

I.     LOCAL   CIRCULATION   OF   AIE   IN   A   HOUSE 


.  To  face  ^^  113 


II.  CHAET  SHOWING  THE  AMOUNT  OF  CAEBONIC  ACID  AT 
VAEIOUS  DEPTHS  IN  THE  SOIL  OF  MUNICH  AND 
CALCUTTA.     (Lewis  and  Cunningham)  .... 


320 


HI.  CHART  SHOWING  THE  RANGE  OF  ATMOSPHERIC  TEM- 
PERATURE AS  COMPARED  WITH  THE  TEMPERATURE 
OF  THE  SOIL  AT  VARIOUS  DEPTHS.  (Fodoe)  . 


322 


IV.    MAP  OF  THE  SOUTH-EAST  OF  ENGLAND  (Kent,  Surbey,n^ 
AND  Sussex) 


Between  pages 
360    and    361,, 

V.    MAP     SHOWING    THE    REGISTRATION    DISTRICTS    OF     f^'^^  ^^  f^^^- 
KENT,  SURREY,  AND  SUSSEX j 


VI.    MICROSCOPIC  APPEARANCES   OF   CHIEF    FIBRES   USED 

FOR  CLOTHING    ....  .        ...  To  face  p.  514 

VII.    PLAN     OF     THE     CITY     HOSPITAL     FOR     INFECTIOUS 

DISEASES,  NEWCASTLE-ON-TYNE „  750 


VIII.  PLAN  SHOWING  RELATIVE  POSITIONS  OF  LAIRAGE, 
SLAUGHTER-HOUSES,  COOLING-ROOMS,  AND  MEAT 
MARKET  ...        


987 


IX.     PLAN    OF   PUBLIC   ABATTOIRS    AND   CATTLE    MARKET, 
SWANSEA        


98& 


CONTEIBUTOES 

TO 

THE     FIKST    VOLUME 


COPEMAN,  S.  MONCKTON,  M.A.,  M.D.  Cantab.,  D.P.H.,  Medical  Inspector  of  the  Local 
Government  Board.     (Soil) 

COEFIELD,  W.  H.,  M.A.,  M.D.  Oxon.,  F.E.C.P.,  Professor  of  Hygiene  and  Public  Health, 
University  College,  London;  Medical  Officer  of  Health,  St,  George's,  Hanover 
Sgtuire.     (The  Disposal  of  Ebjuse) 

HIME,  THOS.  WHITESIDE,  M.A.,  M.D.,  late  Medical  Officer  of  Health,  Bradford. 
(Offensive  and  Noxious  Businesses) 

HOPE,  E.  W.,  M.D.,  D.Sc,  Assistant  Medical  Officer  of  Health;  Lecturer  mi  Public 
Health,    University   College,  Liverpool.    (The   Inspection  of   Meat  :    Slaughtek- 

HOUSES)  * 

HOWSE,  H.  G.,  M.S.  Lond.,  F.E.C.S.,  Surgeon  to,  and  Lecturer  on  Surgery  at,  Guy's 
Hospital.     (Hospital  Hygiene) 

MAETIN,  SIDNEY  H.  C,  M.D.  Lond.,  F.E.C.P.,  Assistant  Physician  to  University 
College  Hospital,  London.     (Food) 

NOTTEE,  J.  LANE,  M.A.,  M.D.,  D.P.H.,  Professor  of  Military  Hygiene,  Army  Medical 
School,  Netley.    (Aie) 

PAEKES,  LOUIS  C,  M.D.  Lond.,  D.P.H.,  Assistant  Professor  of  Hygienic  and  Public 
Health,  University  College,  London ;  Lecturer  on  Public  Health  at  St.  George's 
Hospital ;  Medical  Officer  of  Health  for  Chelsea.     (The  Disposal  of  Eefuse) 

POOEE,  GEO.  VIVIAN,  M.D.  Lond.,  F.E.C.P.,  Physician  to  University  College  Hospital ; 
Professor  of  Forensic  Medicine  and  of  Clinical  Medicine,  University  College, 
London.    (Clothing) 

SHAW,  W.  N.,  M.A.,  F.E.S.,  Lecturer  on  Physics  in  the  University  of  Cambridge. 
(Wabming  and  Ventilation) 

SMITH,  P.  GOEDON,  F.E.I.B.A.,  Architect  to  the  Local  Government  Board.  (The 
Dwelling) 


xii  HYGIENE 

STEVENSON,  THOMAS,  M.D.  Lond.,  F.B.C.P.,  Lecturer  on  Chemistnj  and  on  Medical 
Jurisprudc7ice  at  Guy's  Hospital ;  Official  Analyst  to  the  Home  Office.    (Watek) 

SYMONS,  G.  J.,  F.E.S.,  Secretary  of  the  Royal  Meteorological  Society.     (Meteorology) 

TREVES,  FREDERICK,  F.R.C.S.,  Surgeon  to,  and  Lecturer  on  Surgery  at,  the  London 
Hospital.     (Physical  Education) 

WHITE,  W.   HALE,  M.D,  Lond.,  F.R.C.P.,  Physician  to,  and  Lecturer  on  Materia 
Medica  at,  Gmfs  Hospital.     (Baths) 

WILLIAMS,  C.  THEODORE,  M.A.,  M.D.  Oxon.,  F.R.C.P.,  Physician  to  the  Consumption 
Hospital,  Brompton.     (Influence  of  Climate  on  Health) 

YOUNG,  KEITH,  D.,  F.R.I.B.A.,  Architect  to  the  Middlesex  ami  London  Fever  Hospitals. 
(The  Dwelling) 


AIE 


BY 

J.  LA.NE  NOTTEE,  M.A.,  M.D. 

PEOFESSOB    OF    MILITAEY   HTGIENE    AT    THE    AEMT   MEDICAL    SCHOOL,    NETLEY 


VOL.     I. 


AlK 


Air  is  a  mixture  of  oxygen  and  nitrogen  with  minute  traces  of  other  gases  : 
in  that  collected  near  the  surface  of  the  earth,  mineral  substances  are  always 
present,  together  with  a  variable  amount  of  dead  and  living  organised 
matter. 

Statistics  prove  that  impure  air  is  one  of  the  most  important  of  the 
causes  of  death  which  are  always  present.  Density  of  population  favours 
the  spread  of  organic  impurity  in  the  atmosphere,  consequent  on  dirt,  over- 
crowding, and  poverty,  and  this  unfortunately  is  the  normal  condition  of 
populous  and  manufacturing  towns.  The  same  has  been  observed  with 
respect  to  animals,  the  health  of  the  animals  being  in  direct  proportion  to 
the  purity  of  the  air  they  breathe. 

The  following  is  the  composition  of  average  air  : — 

ComjMsition  of  Atmospheric  Air. 


Oxygen 

Nitrogen 

Carbon  dioxide 

Watery  vapour 

Ammonia    . 

Organic    matter,    dead    or    living, 

unorganised     . 
Ozone 

Salts  of  sodium 
Other  mineral  substances  . 


.     209-6  per  1000  volumes. 
.     790-0 
■         0-4 

.     varies  with  temperature. 
.     trace, 
organised   or\ 


variable. 


The  gases  which  make  up  atmospheric  air  do  not  exist  in  chemical  com- 
bination, but  form  a  mechanical  mixture.  This  is  proved  by  the  fact  that 
they  are  not  found  in  the  air  in  the  proportion  of  their  combining  weights,  nor 
in  any  multiple  of  these,  the  oxygen  being  the  active  agent  required  in  all 
the  processes  of  oxidation  (i.e.  combustion) ;  the  nitrogen  a  passive  agent, 
taldng  no  part  in  the  processes  of  respiration  and  serving  the  purpose  of 
an  innocuous  diluting  agent. 

The  air  we  breathe  in  large  open  spaces  is  liable  to  very  little  change  in 
the  proportion  of  its  chief  constituents  ;  this  is  due  to  the  diffusion  of 
gases,  to  the  influence  of  air-currents,  and  to  the  reciprocal  action  of  animals 
and  plants  upon  it,  and  recent  observations  have  shown  only  slight  differences 
in  its  composition  in  different  parts  of  the  earth. 

The  amount  of  oxygen  in  pure  mountain  air  is  209"8  per  1000  volumes, 
while  in  the  air  of  towns  ^  it  may  fall  as  low  as  208'7  ;  it  is  said  to  be  slightly 
higher  in  wet  weather  or  immediately  after  rain  than  in  dry,  foggy  weather. 

The  amount  of  carbon  dioxide  in  normal  air  ranges  from  0*2  to  0*o  per 
1000  volumes.  Schlagintweit  states  that  it  slightly  increases  up  to  11,000 
feet  in  height  and  then  decreases  ;  but  this  is  denied  by  Tronchet,^  who 
declares  that  the  COg  diminishes  in  amount  above  3300  feet. 


*  Air  and  Bain.    By  R.  Angus  Smith. 

^  Arnould,  Nouveaux  Eliments  d'IIygii7ie,  p. 


286. 


b2 


4  HYGIENE 

Levy  gives,  as  a  mean  of  his  observations  at  Montsouris,  0'208  per  lOOQ 
volumes.  In  the  Dundee  experiments  Carnelley,  Haldane,  and  Anderson  ^ 
found  an  average  of  0"390  and  a  range  of  0*220  to  0*560,  the  mean  during 
the  day-time  being  0-380,  and  during  the  night-time  0-410,  in  open  spaces  ; 
in  close  spaces  at  night  the  mean  was  0'4:20.  In  the  suburbs  the  mean  was 
only  0-280,  vd\h  a  range  of  0-180  to  0-350,  and  in  the  outskirts  of  Perth  a 
mean  of  0-310,  with  a  range  of  0-290  to  0-350. 

The  amount  of  watery  vapour  in  air  varies  with  the  temperature ;  the 
higher  the  temperature  the  more  water  can  be  vaporised ;  the  difference  in 
the  amount  being  often  as  great  as  from  1  to  12  grains  in  a  cubic  foot  of 
air.  It  is  the  most  variable  constituent  of  the  atmosphere,  but  forms  on  an 
average  from  60  to  75  per  cent,  of  the  amount  necessary  for  complete 
saturation. 

Ozone. — The  nature  and  action  of  ozone  are  not  yet  quite  understood.  It 
is  now  generally  admitted  by  chemists  to  be  an  allotropic  form  of  oxygen 
and  a  compound  molecule  made  up  of  three  molecules  (OgO)  of  oxygen, 
while  antozone  is  peroxide  of  hydrogen  (Odling). 

There  is  no  satisfactory  method  of  testing  for  ozone  ;  the  reaction  Avith 
ozone  paper  is  imperfect,  but  certain  results  have  been  recorded  which  are 
fairly  trustworthy.  The  ozone  reaction  is  absent  in  impure  air,  in  the  interior 
of  large  towns,  near  decaying  substances,  and  in  crowded  dwellings ;  there 
is  more  reaction  in  the  suburbs  of  towns  than  in  the  centre,  more  on  the  tops 
of  mountains  than  in  plains,  more  near  the  sea  shore  than  on  flat  inland 
surfaces.  Ozone  is  a  powerful  oxidising  agent,  oxidising  substances  which 
oxygen  will  not  attack ;  the  quantity  contained  in  the  atmosphere  is  very 
small,  probably  rarely  exceeding,  if  even  reaching,  one  part  in  10,000. 

Ammonia  is  always  present  in  the  air,  in  minute  traces,  either  free  or 
combined  :  the  proportion  present  is  at  its  minimum  in  winter,  increases  in 
the  spring,  and  is  highest  in  summer.  Plant  life  derives  its  nitrogen  in 
part  from  this  source. 

Organic  matter,  which  ought  to  be  considered  as  an  impurity,  is  hardly 
ever  absent. 

IMPUEITIES   IN  AIR 

A  variety  of  substances  are  continually  passing  from  the  surface  of  the 
earth  into  the  atmosphere  in  the  condition  of  gases,  vapours,  and  solid  par- 
ticles ;  these  would  accumulate  and  render  the  air  irrespirable  if  their  effects 
were  not  counteracted  by  the  forces  of  nature  which  are  continually  at  work 
in  one  form  or  another.  Diffusion,  dilution  by  wind,  oxidation,  and  the  fall 
of  rain  are  the  chief  purifying  agents,  while  the  processes  going  on  in  the 
vegetable  world  diminish  the  amount  of  carbon  dioxide  evolved  and  keep  it 
within  certain  limits  :  gases  diffuse  and  are  rapidly  diluted  and  dispersed  by 
winds  so  as  to  be  rendered  innocuous.  It  is  only  in  the  air  of  enclosed 
spaces,  when  the  natural  processes  of  purification  are  arrested,  that  any  great 
deviation  from  the  normal  standard  occurs. 

SUSPENDED   MATTEES   IN   THE   AIR 

An  immense  number  of  substances  pass  into  the  air  and  may  be  sus- 
pended in  the  atmosphere.  The  nature  of  the  suspended  matters  depends 
chiefly  on  the  locality  and  other  varying  conditions.  Air  of  elevated  sparsely 
inhabited  places  is  almost  free  from  suspended  matters,  while  in  low-lying 
and  thickly  populated  districts  they  are  very  abundant,  and  Pasteur  has 
'  Philosophical  Transactions  Royal  Society,  No.  178  (1887). 


AIB  5 

shown  the  immense  difference  in  this  respect  between  the  air  of  glaciers  and 
that  of  inhabited  regions  at  a  slightly  lower  level. 

The  suspended  matters  in  the  externoi  air  are  partly  mineral,  partly 
organic. 

The  mineral  matters  consist  largely  of  silica,  peroxide  of  iron,  chalk,  clay, 
soot,  chloride  of  sodium,  &c.  These  are  most  present  in  the  air  in  dry 
weather,  rain  not  only  preventing  such  particles  being  lifted  by  the  wind,  but 
also  washing  all  suspended  matters  out  of  the  air  and  so  purifying  it. 

The  organic  suspended  matters  consist  principally  of  grains  of  pollen, 
algse,  fragments  of  hair,  wood,  straw,  stable  manure,  debris  of  insects,  &c. 
In  Southern  Europe  and  Africa  diatoms  may  be  seen,  but  they  are  seldom 
found  in  this  country.  Ehrenberg  gives  the  microscopic  examination  of 
seventy  showers  :  in  addition  to  particles  of  sand  and  oxide  of  iron  he  dis- 
covered very  many  different  living  forms,  chiefly  rhizopods,  tardigrades,  and 
anguillulse.  In  larger  towns,  especially  where  manufacturing  works  exist, 
the  air  is  often  loaded  with  soot  and  dust  of  organic  origin,  which  floats  in 
considerable  quantities  near  the  surface  of  the  ground.  In  an  analysis  of  street 
dust  made  by  Mr.  Tichborne  ^  in  Dublin  he  showed  that  the  organic  matter 
present  varied  from  45*2  per  cent,  in  the  air  of  the  street  to  29*7  per  cent,  at 
the  top  of  Nelson's  Pillar  (134  feet  high) ;  the  organic  matter  was  chiefly 
finely  ground  stable  manure :  it  acted  as  a  ferment  and  reduced  nitrate  of 
potassium  to  nitrite.  In  de  Chaumont's  experiments  at  St.  Mary's  Hospital, 
Paddington,  and  University  College  Hospital,  the  suspended  matter  collected 
from  the  external  air  included  the  following  substances  :  epidermis  of  hay, 
fragments  of  pine  wood,  linen  and  cotton  fibre,  epithelium  from  the  mucous 
surfaces,  feathers,  charred  vegetable  particles,  and  mineral  matter.  When 
the  air  is  motionless  these  suspended  matters,  as  a  rule,  subside,  though  some 
are  so  light  as  to  float  in  rarefied  air,  and  Tyndall  has  shown  that  if  burnt  a 
little  bluish  mist  arises  from  the  combustion,  indicating  that  those  consumed 
are,  from  their  destructible  nature,  of  organic  origin. 

The  presence  of  bacteria  in  external  air  has  recently  been  the  subject 
of  close  investigation.  They  flourish  whenever  they  meet  with  sufficient 
moisture,  nutritive  material,  and  a  suitable  temperature  (above  60°  Fahr.)  ; 
they  appear  to  pass  into  air  from  colonies  lying  on  the  surface  of  the  earth 
which  are  broken  up  and  afterwards  scattered  by  wind.  Once  passing  into  the 
air  they  float  about  in  the  atmospheric  currents  ;  a  few  adhere  to  the  grosser 
particles  of  dust  and  fall  in  quiescent  air,  while  others  are  not  deposited  even 
in  air  which  is  at  rest.  Their  numbers  depend  on  local  conditions,  as  when 
there  is  nutriment  for  a  plentiful  development  on  the  surface  of  the  earth  and 
where  the  superficial  colonies  are  broken  up  ;  this  is  partly  the  reason  that 
bacteria  are  not  found  in  high  mountains,  over  desert  plains,  or  on  the  sea. 
This  is  well  shown  by  the  following  examples  given  by  Miquel : — 

jMicrobes  per  cubic 
metre  of  air 
High  Mountains  .....  1 

Mid-Atlantic  Ocean       .....  6 

Hotel  Dieu  (Paris)         .....     79,000 

It  is  not  known  how  far  bacteria  can  be  carried  by  wind,  but  as  dust 
■can  be  conveyed  to  an  almost  indefinite  distance  (as  shown  by  the  eruption  of 
Krakatoa,  which  is  supposed  to  have  scattered  fine  dust  over  the  greater  por- 
tion of  the  globe)  it  is  not  unnatural  to  presume  that  bacteria  also  may  be 
carried  over  considerable  areas.  Fischer,  however,  states  that  he  found  no 
:microbes  beyond  120  miles  from  land. 

'  Chemical  News,  1871. 


6  HYGIENE 

Of  the  physical  conditions  of  the  air  which  influence  the  number  of 
bacteria,  dry  winds  and,  in  towns  especially,  drought  lasting  for  some  time, 
favour  their  increase  ;  during  this  latter  period  many  varieties  of  bacteria, 
and  even  pathogenic  bacteria,  pass  into  the  air.  The  amount  of  aqueous 
vapour  present  also  influences  the  number  of  bacteria,  as  the  condensation  of 
vapour  leads  to  the  sinking  of  the  particles  of  dust  to  which  the  bacteria 
adhere,  while  rain  washes  the  air  and  brings  back  to  the  earth  the  greater 
number  of  these  organisms.  In  external  air  the  pathogenic  bacteria  form 
only  an  infinitesimal  part  compared  with  the  saprophytes,  and  all  recent 
experience  goes  to  show  that  the  danger  from  the  entrance  of  pathogenic 
bacteria  fi-om  external  air  into  wounds  is  extremely  small,  and  that  this  is 
occasioned  far  more  frequently  by  other  causes. 

Miquel  in  his  experiments  found  the  air  of  Montsouris  to  contain  on  an 
average  (mean  of  six  years'  observations)  450  microbes  per  cubic  metre  of  air, 
but  these  were  chiefly  in  the  form  of  spores.  In  the  streets  of  Paris  the 
average  number  to  a  cubic  metre  of  air  was  900. 

In  the  Dundee  experiments  Carnelley,  Haldane,  and  Anderson  found  the 
average  number  of  organisms  to  be  less  than  one  per  litre,  in  the  proportion 
of  three  bacteria  to  one  mould. 

The  present  evidence  goes  to  prove  that  in  the  open  air  the  dilution  of 
bacteria  is  so  great,  and  the  number  of  pathogenic  bacteria  so  very  small, 
that  no  danger  is  to  be  apprehended  from  them  unless  they  originate  from 
local  soiTrces  of  impurity. 


DISEASES   PKODTJCED  BY   IMPUEITIES   IN   AIE 

For  many  years  attention  has  been  directed  to  the  great  amount  of 
respiratory  disease  caused  by  dust  inhaled  into  the  lungs  by  those  who 
worked  at  certain  trades,  and  a  large  number  of  facts  relating  to  this  sub- 
ject have  been  collected :  acute  pneumonia,  bronchitis,  and  non-tubercular 
phthisis  are  produced,  the  severity  of  these  diseases  depending  chiefly  on. 
the  amount  of  dust  and  on  its  physical  conditions  with  regard  to  angularity, 
roughness,  or  smoothness  of  its  particles. 

The  suspended  matter  in  the  air  may  be  of  animal,  vegetable,  or  mineral 
origin,  but  it  is  the  latter  chiefly  that  gives  rise  to  the  most  severe  results,  as 
is  seen  in  the  case  of  miners  of  all  kinds.  Dr.  Ogle^  has  shown  the  excessive 
mortality  produced  among  Cornish  miners  from  phthisis  and  other  respi- 
ratory diseases.  The  '  comparative  mortality  figure  '  in  1880 — 82  was  1889, 
that  of  all  males  in  England  and  Wales  being  1000,  and  Cornish  males  887  ; 
from  phthisis  and  other  respiratory  diseases  the  comparative  mortality 
amongst  Cornish  miners  was  1148,  while  amongst  coal  miners  generally 
throughout  England  and  Wales  these  diseases  gave  only  328.  It  would 
appear  that  this  excessive  mortality  is  due  to  some  condition  peculiar  to 
tin  mining  (which  is  almost  exclusively  carried  on  in  Cornwall),  where  the 
dust  disengaged  is  more  irritant  and  ventilation  less  perfect  than  in  other 
mines.  Owing  to  improvements  in  the  system  of  ventilation  adopted  in 
mines  (especially  those  in  South  Staffordshire  and  South  Wales)  during  the 
last  few  years,  there  has  been  a  great  decrease  in  lung  affections,  although 
chronic  bronchitis,  asthmatical  breathing,  and  vicarious  emphysema  still  pre- 
vail. The  workers  in  lead  mines  suffer  from  lead  poisoning  and  bronchitis,. 
due  to  inhalation  of  dust,  and  at  Reeth,  in  Yorkshire,  where  one-half  the  male 

'  Forty-fifth  Beport  of  the  Eegistrar-Gencral. 


AIB  7 

population  work  in  lead  mines,  the  deatlis  from  respiratory  diseases  are 
double  those  of  the  agricultural  population.  In  copper  mines  the  dust  of 
copper  ore  is  credited  with  producing  severe  gastric  and  intestinal  irritation, 
characteristic  of  copper  poisoning.  Among  this  class  of  workmen  there  is  a 
peculiar  browning  of  the  skin,  wasting,  dyspnaja,  cough,  and  coloured  expec- 
toration. The  manufacture  of  pottery,  in  which  a  large  quantity  of  mineral 
dust  is  thrown  into  the  air,  is  productive  of  much  disease:  the  clay  used  con- 
sists of  disintegrated  granite  mixed  with  powdered  flint,  while  in  some  cases 
felspar  is  added.  The  clouds  of  dust  given  off  in  the  various  processes  are  ex- 
ceedingly irritating  to  the  lung  structure,  even  more  so  than  in  coal  mining  ; 
partial  condensation  of  the  lung  substance,  due  to  the  slow  inflammatory 
action  caused  by  the  inhalation  of  these  irritating  particles,  follows,  and 
produces  the  condition  known  as  *  potter's  lung.'  Emphysema  is  common, 
its  general  features  being  that  those  affected  resemble  asthmatical  subjects  ; 
the  disease  is  frequently  complicated  with  phthisis. 

Steel  grinders  suffer  most  severely  from  the  entrance  of  particles  of  dust 
into  their  lungs,  but  the  further  development  of  the  process  of  wet  grinding 
has  of  late  years  somewhat  lessened  this  evil,  and  improved  ventilation  by 
means  of  fans  has  also  effected  a  considerable  diminution  in  the  numbers 
•  attacked  and  in  the  mortality.  In  the  needle  trade,  which  is  altogether  dry 
grinding,  extraction  tubes  are  attached  to  each  grindstone,  and  the  greater 
part  of  the  dust  is  collected  and  drawn  from  the  workman  ;  notwithstanding 
this,  lung  affections  are  extremely  prevalent,  while  the  mortality  from  tuber- 
cular phthisis  and  scrofula  is  excessive. 

The  inhalation  of  dust  of  vegetable  origin  produces  much  the  same  train 
of  symptoms.  In  the  sorting,  scutching,  and  carding  of  cotton  the  intro- 
duction of  closed  machinery  has  done  much  to  mitigate  the  evils  arising  in 
the  process  of  manufacture.  In  the  spinning  and  sizing  of  cotton  much  dust 
is  given  off.  In  flax  factories  a  very  irritant  dust  is  produced,  known  among 
the  workers  as  '  pounce  '  ;  those  exposed  to  it  suffer  from  severe  dyspnoea, 
paroxysmal  in  character,  and  the  dust  inhaled  is  exceedingly  difficult  to  get 
rid  of  by  expectoration  ;  it  produces  a  whole  train  of  nervous  symptoms. 
Women  suffer  most  severely,  as  they  form  the  majority  of  employes  in  the 
mills.  The  dust  arising  from  the  manufacture  of  silk  is  less  irritating  ;  it 
is  difficult  to  say  whether,  apart  from  other  conditions  present,  the  amount 
of  dust  is  as  destructive  as  in  other  trades. 

In  the  manufacture  of  '  shoddy  '  a  large  quantity  of  irritant  dust  escapes 
from  the  machines,  producing  a  febrile  condition  characterised  by  headache, 
sickness,  difficulty  of  breathing,  cough,  and  expectoration.  Stonecutters 
suffer  severely  from  the  inhalation  of  stony  particles,  which  set  up  slow 
inflammation  in  the  lungs  ;  those  working  on  hard  and  flinty  stones  are  most 
affected.  It  is  said  that  men  cannot  continue  working  at  this  class  of  stone  for 
more  than  eight  years,  although  during  the  first  three  or  four  years  they 
suffer  very  little  from  it.  The  makers  of  Portland  cement  inhale  a  consider- 
able quantity  of  finely  ground  cement,  when  transferring  it  into  sacks  ;  it 
prevents  their  continuing  at  the  same  work  for  a  number  of  days  in  succes- 
sion ;  they  frequently  expectorate  little  masses  of  cement. 

Electroplate  and  Britannia  metal  workers  suffer  from  the  large  quantity 
of  dust  evolved  in  the  polishing  and  cleaning  with  lime,  and  from  minute 
particles  of  the  metal  which  become  detached.  Workers  of  mother-of-pearl 
and  ivory  also  suffer  to  a  considerable  extent,  the  fine  dust  gi^^ing  rise  to  lung 
irritation,  cough,  and  hsemoptysis. 

The  mortality  among  workers  in  certain  dust-producing  trades  from 
phthisis  and  respiratory  disease,  as  compared  with  the  mortality  in  England 


8  HYGIENE 


and  Wales  generally,  is  shown  in  the  following  table,  deaths  from  all  causes 
in  males  being  taken  as  1000  : — 

Comparative  Mortality. 


Phthisis. 

Eespiratory  Diseases. 

All  males  (England  and  Wales) 

.     220 

182 

Earthenware  manufacturers     . 

.     473 

645 

File  makers 

.     433 

350 

Miners,  Cornwall 

.     690 

458 

Painters 

.     461 

166 

The  makers  of  matches  formerly  suffered  from  necrosis  of  the  lower  jaw, 
if  there  was  any  exposed  part  on  which  the  fumes  of  phosphorus  could  act. 
The  substitution  of  red  or  amorphous  phosphorus  has  obviated  this  danger, 
as  this  does  not  vaporise,  and  is  therefore  harmless. 

In  some  trades  the  fumes  of  metals  as  well  as  particles  of  metallic  dust 
pass  into  the  air.  Plumbers  inhale  volatilised  oxide  of  lead,  which  rises 
during  the  process  of  casting,  and  also  from  the  fumes  produced  in  burning 
off  old  paint ;  formerly  a  large  mortality  followed  the  grinding  of  white  lead, 
but  since  the  moist  process  has  been  substituted  less  harm  results. 

Brassfounders  are  subject  to  bronchitis  and  asthma,  and  also  '  brass- 
founder's  ague,'  which  is  said  to  be  produced  by  the  fumes  of  zinc  oxide ;  the 
symptoms  are  febrile,  attended  with  nervous  depression,  which  obhges  them 
to  cease  work  for  a  few  days.  Coppersmiths  are  occasionally  affected  in  the 
same  way,  from  inhaling  the  fumes  of  the  partly  volatilised  metal.  In  the 
manufacture  of  tobacco  some  dust  is  given  off,  which  produces  for  a  short  time, 
in  those  newly  employed,  at  the  work,  nausea,  giddniess,  and  irritation  to  the 
eyes,  but  they  soon  become  inured  to  their  work. 

Workers  in  mercury  are  subject  to  mercurialism,  and  formerly  salivation 
and  palsy  were  common,  but  this  has  greatly  diminished  since  electricity 
has  rendered  gilding  with  the  aid  of  mercury  obsolete,  and  the  manufac- 
ture of  mirrors  from  nitrate  of  silver  has  practically  abolished  mercurial 
affections. 

Arsenic  in  the  form  of  Scheele's  or  emerald  green  is  the  cause  of  great 
suffermg  to  workmen  employed  in  the  making  of  artificial  flowers  or  wall 
papers,  as  well  as  those  who  occupy  rooms  so  papered.  Such  persons 
suffer  from  painful  rashes,  sore  eyes,  sickness  of  stomach,  and  generally  the 
symptoms  of  arsenical  poisoning. 

Gas  makers  frequently  suffer  from  the  noxious  effluvia  given  off  by  the 
refuse  lime  used  in  the  making  and  purifying  of  gas. 

In  addition  to  inorganic  substances  and  metals  there  are  organised  and 
living  bodies  which  are  suspended  in  the  air,  such  as  pollen  of  flowers,  algse, 
fungi,  and  bacteria.  Hay  fever  is  produced  in  susceptible  persons  by  the 
pollen  of  flowers  (especially  Anthoxanthum  odoraktm)  ;  the  spores  of  fungi 
are  known  to  cause  diseases  of  the  skin  in  man,  and  they  may  certainly  be 
regarded  as  the  medium  by  which  such  diseases  as  tinea  and  favus  are 
spread. 

Dr.  Salisbury,^  of  Newark,  Ohio  (U.S.A.),  has  demonstrated  his  ability  to 
produce  a  disease  indistinguishable  from  measles  by  inoculations  of  the  fungi 
from  mouldy  straw,  but  his  experiments  have  not  been  confirmed.  Measles 
is  also  said  to  have  been  produced  by  the  fungi  growing  on  linseed  meal.^ 
Hallier,  of  Jena,  also  favours  the  view  that  fungi  spores  are  the  cause  of 
specific  diseases.     That  bacteria  of  various  kinds  produce  disease  appears 

*  American  Journal  of  Medical  Sciences. 

*  Dublin  Journal  of  Medical  Science,  vol.  xxxv.  1863,  p.  60, 


AIB  9 

now  to  be  finally  settled  and  accepted.  Many  have  been  cultivated  in  pure 
cultures,  their  life-history  studied,  and  particular  species  identified,  and  the 
disease  produced  by  inoculation.  As  examples  may  be  mentioned  B. 
anthracis  in  woolsorter's  disease,  B.  tuberculosis  in  phthisis,  B.  leproi  in 
leprosy,  and  B.  Obermeieri  in  relapsing  fever. 

Certain  diseases  appear  to  be  more  associated  with  impure  air  than 
others  ;  whether  the  contagia  are  capable  of  growth  and  multiplication  in 
the  air  is,  uncertain,  but  that  they  can  retain  their  vitality  for  a  long  time 
there  can  be  no  doubt :  the  poisons  of  scarlet  fever,  smallpox,  and  enteric 
fever  retain  their  powers  of  infection  for  weeks,  and  are  capable  of  exciting 
disease  in  any  person  susceptible  to  their  influence.  The  specilic  poisons  of 
various  diseases  differ  in  the  way  in  which  they  are  destroyed  or  rendered 
innocuous  by  dilution  ;  the  poison  of  typhus  fever  is  very  volatile,  rapidly 
diffuses,  and  is  perhaps  oxidised  and  got  rid  of  by  free  ventilation ;  so  that  an 
interval  of  a  few  feet  gives  under  such  circumstances  sufficient  protection, 
while  exactly  opposite  conditions  appear  to  be  the  case  with  the  poisons  of 
smallpox  and  scarlet  fever.  The  poisons  of  cholera  and  diphtheria  also  are 
believed  to  be  borne  some  distance  by  wind,  and  malaria  has  been  known  to 
be  conveyed  thus  for  several  hundred  yards  without  its  infective  power  being 
lessened. 

GASEOUS  MATTEES  IN  THE  AIE 

Carbon  dioxide. — Normal  air  contains  from  3  to  6  parts  of  carbon  dioxide 
in  10,000  ;  the  amount  increases  during  the  night  and  diminishes  after  sunrise  : 
it  is  less  over  large  tracts  of  water  than  over  land,  and  is  more  abundant 
in  crowded  cities  than  in  the  open  country.  The  addition  of  10  to  15  per 
cent,  of  CO2  to  air  would  render  it  poisonous,  although  larger  quantities  are 
said  to  have  been  inhaled  without  injury.  Dr.  Taylor  states  that  in  mines 
in  Cornwall  where  the  air  contains  not  more  than  2  per  cent,  the  miners 
suffer  considerably,  but  other  circumstances  than  the  CO2  have  here  to  be 
taken  into  account.  In  Dr.  Angus  Smith's  experiments  one  per  cent,  of  this 
gas  in  air  from  which  the  organic  matter  of  respiration  had  been  elimi- 
nated produced  slowness  of  the  heart's  action  with  quickening  of  the  respira- 
tions ;  it  is,  however,  uncertain  what  would  be  the  effects  produced  by 
breathing  continuously  an  atmosphere  containing  1  or  1*5  per  cent,  of  this 
gas ;  when  it  reaches  this  amount  organic  matters  and  possibly  other  gases 
are  present  and  the  quantity  of  oxygen  is  also  lessened. 

Carbon  monoxide. — The  poisonous  action  of  carbon  monoxide  renders  a 
very  small  quantity  of  this  gas  dangerous.  Experiments  tend  to  show  that 
when  it  is  absorbed  by  the  blood  it  combines  with  the  hsemoglobin  ;  it  appears 
to  act  as  a  pure  narcotic  poison. 

The  large  quantity  of  CO  (as  much  as  34  per  cent.)  in  '  water  gas  '  renders 
its  employment  dangerous  as  an  illuminant,  the  gas  being  inodorous  and 
unirritating ;  poisonous  effects  are  produced  if  it  is  inhaled.  To  avoid  this 
risk  it  has  been  suggested  to  '  odorise  '  it,  and  mercaptan  and  pyridine  have 
been  employed  for  that  purpose. 

Boburite,  a  mixture  of  dinitrobenzene,  chloronitrobenzene,  and  am- 
monium nitrate,  has  been  lately  used  as  an  explosive  in  mines.  The  fumes 
resulting  from  the  use  of  this  compound  give  rise  to  blueness  of  the  lips, 
headache,  some  dyspnoea  and  loss  of  muscular  power,  drowsiness,  and 
■  occasionally  vertigo  followed  by  vomiting;  carbon  monoxide  is  produced  by 
.its  explosion.^ 

'  British  Medical  Jourjial,  June  15,  1889. 


10  HYGIENE 

Sichcrlieit  explosive  causes  somewhat  similar  symptoms,  and  especially 
marked  cyanosis,  in  those  employed  in  its  manviiaeture. 

Hydroijcn  sulphide. — The  eii'ects  produced  by  the  inhalation  of  this  gas 
vary  according  to  the  degree  of  its  dilution.  If  present  in  somewhat  large 
quantities,  nausea,  headache,  irregular  action  of  the  heart,  and  even  convulsions 
follow,  but  in  dilute  doses  it  produces  only  low  febrile  symptoms  resembling 
typhoid  fever.  The  bad  effects  caused  by  the  inhalation  of  this  gas  are 
mostly  to  be  traced  to  the  opening  of  old  drams  and  cesspits.  Dr.  Letheby 
considers  one  per  cent,  in  the  air  would  be  destructive  to  human  life.  Hirt  has 
no  doubt  that  the  inhalation  of  small  quantities  of  this  gas  produces  chronic 
poisoning  in  those  exposed  to  the  fumes. 

Disulpliide  of  carbon. — The  extensive  use  of  carbon  disulphide  in  india- 
rubber  manufactories  produces  chronic  poisoning,  due  to  the  vapours  given 
off.  The  symptoms  are  headache,  giddiness,  and  excitement  of  the  nervous 
system,  and  these  may  be  followed  by  insanity.  The  vapour  is  exceedingly 
offensive,  nauseous,  and  very  inflammable. 

Ht/drocJiIoric  acid  vapours  when  inhaled  are  extremely  irritating  to  the 
lungs,  causing  bronchitis,  pneumonia,  and  ulceration  of  the  trachea.  This 
and  other  acids  are  used  in  some  of  the  processes  for  the  making  of  steel ; 
unless  protected,  the  eyes  also  suffer. 

Ammoniacal  vapours  are  given  out  in  some  manufactures  ;  but  they  have 
not  been  noticed  to  have  any  injurious  effect  on  the  health  of  operatives, 
except  occasionally  producing  inflammation  of  the  conjunctiva. 

Organic  effluvia. — Effluvia  are  produced  in  nearly  all  the  trades  in  which 
animal  products  are  concerned,  such  as  in  tanning,  leather  dressing,  glue 
making,  soap  works,  slaughter-houses,  gut  scraping  ;  there  are  also  the 
effluvia  arising  from  stables,  cow-sheds,  pig-styes,  &c. ;  although  there  is  no 
evidence  to  show  that  persons  actually  employed  in  these  trades  suffer  in 
health,  there  is  a  well-grounded  belief  that  the  general  health  of  those  living 
in  the  immediate  neighbourhood  is  lowered,  and  that  diseases  in  their  case 
are  apt  to  assume  a  more  severe  type.  Some  of  those  exposed  to  these 
emanations  suffer  at  first  from  loss  of  appetite,  nausea,  vomiting,  and 
diarrhoea,  while  residents  in  the  vicinity  appear  more  frequently  affected  than 
those  actually  employed  in  the  trade. 

Excessive  humidity. — Excessive  moisture,  which  is  nearly  always  asso- 
ciated with  high  temperature,  is  found  in  weaving  sheds  and  also  in  certain 
branches  of  the  silk  trade.  Steam  is  injected  into  the  sheds  in  order  ta 
communicate  the  necessary  amount  of  humidity  without  which  the  warp, 
which  is  sized  with  china  clay,  could  not  be  woven ;  in  consequence  the 
weavers  work  in  damp  clothes  and  fill  their  lungs  with  moisture  ;  they  are 
very  liable  to  bronchitis,  due  to  chill  on  leaving  the  overheated  factory,  and 
lung  diseases  cause  a  large  mortality  among  them.  Hat  makers,  who  work 
imder  somewhat  similar  conditions,  suffer  in  the  same  way. 

Effect  of  air  rendered  impure  by  respiration. — Air  rendered  impure  by 
respiration  may  cause  heaviness,  headache,  and  nausea,  the  poisonous  agent 
present  being  the  organic  matter  :  there  is  also  generally  a  deficiency  of 
oxygen.  When  the  air  is  rendered  very  impure  it  is  rapidly  fatal,  as  in  the 
cases  of  the  Black  Hole  at  Calcutta  and  of  the  steamer  'Londonderry.' 
This  vessel  left  Sligo  for  Liverpool,  and  stormy  weather  coming  on  the  captain, 
forced  200  steerage  passengers  into  their  cabin,  which  measured  18  feet  by 

11  feet  and  7  feet  high.  The  hatches  were  battened  down  and  covered  with 
tarpaulin :  when  the  cabin  was  opened  seventy-two  persons  were  found  dead 
and  several  expiring.  Persons  whose  occupation  obliges  them  to  continuously 
breathe  a  vitiated  atmosphere  become  pale  and  anaemic,  and  suffer  from  loss- 


AIB  11 

of  appetite,  headache,  &c.  Such  persons  are  more  prone  to  phtliisis  and 
diseases  of  the  respiratory  organs  than  those  whoso  occupation  admits  of 
their  passing  their  time  in  well-ventilated  rooms  or  in  the  open  air.  Sedentary 
habits,  want  of  exercise,  improper  food,  added  to  the  influence  of  impure  air, 
are  extremely  productive  of  phthisis  ;  but  it  has  been  clearly  shown  that 
breathing  air  rendered  impure  by  respiration  is  more  potent  than  any  other 
condition  which  predisposes  to  this  disease.  A  good  example  of  this  may  be 
found  in  the  army,  especially  in  foreign  stations,  where  an  increase  of  the 
cubic  space  allowed  to  each  man  and  the  means  adopted  to  remove  foul  air 
have  caused  a  notable  decline  in  the  cases  of  phthisis,  and  the  only  circum- 
stance which  has  brought  about  this  change  at  these  places  is  the  condition 
of  the  air.  The  same  results  are  seen  on  service  in  the  field,  where  the  rudest 
shelter  is  better  than  overcrowded  barracks.  In  the  Afghan  War  pneumonia 
was  very  prevalent  and  fatal  in  the  overcrowded  barracks,  while  there  was 
not  a  single  case  among  those  in  tents  ;  distributing  the  men  in  tents  had 
the  effect  of  at  once  stopping  the  disease. 

Air  rendered  impure  by  exhalations  from  the  sick  is  well  known  to  be 
injurious.  In  military  hospitals  hospital  gangrene  and  erysipelas  were 
among  the  most  prevalent  diseases  in  former  wars  ;  now  they  are  almost 
unknown,  and  the  occurrence  of  a  case  is  considered  evidence  of  neglect. 
The  organic  emanations  being  greater  from  the  sick  than  from  those  in  health 
and  the  metamorphosis  of  tissue  more  active,  pure  air  is  essentially  necessary 
to  facilitate  recovery. 

The  effect  of  breathing  air  into  which  the  products  of  gas  combustion 
have  passed  is  to  be  seen  in  workmen  who  are  obliged  from  the  darkness  of 
their  shops  to  burn  gas  during  a  large  part  of  the  day.  Bronchial  affections 
are  common,  and  in  proportion  to  the  amount  of  contamination  of  the  air 
they  suffer  from  headache,  drowsiness,  and  oppression.  Another  example 
of  the  injurious  effects  produced  by  gas  may  be  inferred  from  the  fact 
that  in  the  Savings  Bank  Department  in  Queen  Victoria  Street,  where  1200 
persons  are  employed,  the  introduction  of  the  electric  light  in  place  of  gas  has 
so  far  reduced  the  absences  from  illness  that  the  extra  labour  gained  has 
paid  for  the  electric  light. 

Air  polluted  by  sewage  emanations,  whether  arising  from  sewers,  drains^ 
or  cesspits,  is  capable  of  causing  vomiting,  diarrhoea,  and  great  prostration. 
When  inhaled  largely  diluted  it  produces  headache  and  a  general  low  state 
of  health  ;  children  appear  to  be  more  susceptible  to  its  influence  than  grown- 
up people ;  they  become  languid  and  may  suffer  from  diarrhoea  and  sore 
throat.  The  special  diseases  that  have  been  more  particularly  noticed  in 
connection  with  sewer  air  are  enteric  fever,  diarrhoea,  and  diphtheria.  As 
regards  enteric  fever  there  is  doubtless  a  distinct  causal  connection  between 
the  inhalation  of  sewer  air  and  the  occurrence  of  the  disease.  The  persistent 
attacks  of  enteric  fever,  which  formerly  occurred  at  Eastney  Barracks,  were 
due  to  sewer  air  being  forced  back  by  the  tide,  no  traps  or  ventilating  open- 
ings being  supplied  ;  since  this  was  remedied  and  ventilation  carried  out  no 
case  of  fever  has  occurred. 

On  the  other  hand  enteric  fever  does  not  appear  to  be  more  common 
among  sewer  men  than  others,  and  those  workmen  employed  on  sewage 
works  do  not  furnish  an  unusual  number  of  cases. 

If  we  admit  the  extreme  danger  which  arises  from  the  inhalation  of  sewer 
air,  knowing  that  the  specific  cause  lies  in  the  intestinal  discharges  which 
naturally  pass  into  the  sewers,  every  procurable  means  should  be  adopted  to 
prevent  the  entrance  of  sewer  gas  into  houses,  although  the  subject  presents 
difficulties  which  cannot  always  be  explained. 


12  HYGIENE 

With  regard  to  diarrhoea  a  worse  type  generally  prevails  in  badly  drained 
than  in  well-drained  districts  :  this  disease,  though  intimately  associated 
with  soil  temperature,  is  favoured  by  sewer  emanations.  In  London  a  heavy 
fall  of  rain  has  checked  its  spread — possibly  by  seahng  traps  which  a 
previous  drought  had  caused  to  become  dry,  and  thus  preventing  sewer  gas 
from  escaping. 

The  spread  of  diphtheria  has  been  ascribed  to  the  pollution  of  air  by 
emanations  from  sewers,  and  certainly  there  is  a  close  connection  between 
the  sanitary  condition  of  a  district  and  the  occurrence  of  this  disease  ;  the  in- 
habitants of  houses  into  which  sewer  gas  enters  are  especial  sufferers.  Refer- 
ence may  be  made  to  outbreaks  recently  recorded  by  the  late  Mr.  Spear,  of  the 
Local  Government  Board.  There  is  no  evidence  to  prove  that  the  emanations 
from  well-managed  sewage  farms  are  injurious  to  health.  Dr.  Carpenter  has 
shown  that  the  sewage  farm  at  Beddington  can  be  carried  on  without  risk  to 
persons  in  the  vicinity,  and  where  exhalations  have  been  said  to  produce 
disease  the  fault  has  been  with  the  improper  treatment  of  the  sewage  and 
not  with  the  principle. 

The  fouling  of  streams  and  rivers  does  not  furnish  such  clear  evidence  ; 
though  the  cases  recorded  among  residents  in  houses  on  the  quays  in  Dublin 
or  in  the  worst  districts  in  Lancashire  show  no  great  excess  of  disease,  there 
is  nevertheless  considerable  proof  that  inhalation  of  offensive  odours  is  often 
productive  of  diarrhoea.  Probably  the  results  much  depend  on  the  dilution 
of  the  sewage  matter.  When  very  dilute  there  appears  to  be  little  danger 
from  evaporation. 

The  air  of  graveyards  contains  an  excess  of  CO2,  and  when  they  are  densely 
crowded,  and  deep  burial  is  not  insisted  on,  there  are  also  found  foetid  organic 
vapours,  sulphuretted  hydrogen,  and  ammonium  sulphide,  which  increase  the 
sickness  and  mortality  among  those  living  in  the  immediate  vicinity  ;  any 
disease  occurring  in  such  a  situation  assumes  a  virulent  and  unfavourable  type. 
But  under  modern  regulations  there  appears  to  be  no  danger  from  this  cause. 
Care  must  be  taken,  however,  that  no  contamination  reaches  the  water  supply, 
especially  that  used  for  drinking  purposes.  In  India  it  is  well  known  that 
cholera  assumes  a  more  severe  and  fatal  type  in  stations  where  barracks  are 
built  in  close  proximity  to  the  sites  of  old  burial-grounds.  A  remarkable 
case  occurred  in  Yorkshire  ^  a  few  years  ago,  in  connection  with  a  churchyard, 
where  a  number  of  persons  who  died  from  scarlet  fever  had  been  buried  thirty 
years  previously.  A  part  of  the  churchyard  was  closed,  but  was  afterwards 
iacluded  in  the  garden  of  the  Rector,  who  had  it  dug  up,  whereupon  scarlet 
fever  broke  out  in  his  family  and  spread  to  the  neighbouring  houses. 
Gravediggers  appear  to  suffer  no  injurious  effects  from  their  calling ;  no 
excess  of  mortality  among  them  is  recorded. 

The  elHuvia  arising  from  decomposing  carcases  produce  diarrhoea,  dysen- 
tery,  and  a  low  febrile  condition  ;  this  has  been  especially  noticed  in  military 
campaigns,  where  it  is  often  impossible  to  bury  horses  that  have  died  or  been 
killed  in  action.  In  well-managed  knackeries  the  men  do  not  appear  to 
suffer,  although  it  is  said  that  glanders  and  malignant  pustule  have  been 
caught  in  this  way. 

The  air  of  brickfields,  especially  those  in  which  the  bricks  are  burnt  in  a 
quadrangular  pile  and  not  in  kilns,  is  very  offensive  ;  sulphuretted  hydrogen, 
<3arbon  dioxide,  carbon  monoxide,  and  foetid  organic  vapours  with  thick  smoke 
are  given  off,  particularly  when  house  refuse  is  used  in  the  manufacture. 
The  emanations  are  acid  and  destroy  vegetation ;  when  inhaled  they  are 
very  irritant.     In  burning  cement  the  same  disagreeable  effects  are  produced, 

•  Sanitary  Journal,  December  17,  1888. 


AIB 


13 


the  gases  given  off  being  chiefly  CO2  and  SH^,  also  volatile  cyanides  in  some 
instances,  which  are  very  poisonous. 

The  air  of  marshes  has  given  rise  to  malarial  fevers,  the  specific  poison 
being  rapidly  carried  by  the  v^ind  to  a  considerable  distance ;  it  is  more 
intense  near  the  ground  than  a  few  feet  above  it,  and  is  easily  stopped  by 
mechanical  barriers.  This  disease  is  now  seldom  seen  in  England,  but  is 
very  prevalent  in  the  tropics  during  the  rainy  season. 


ON   WHAT   BASES   AKE   WE   TO   CALCULATE   THE  AMOUNT   OF   FRESH 

AIR  REQUIRED? 

In  order  to  calculate  the  amount  of  fresh  air  required  to  maintain  an  in- 
habited room  or  enclosed  space  in  a  well-ventilated  condition,  it  is  necessary 
(1)  to  know  the  nature  and  amount  of  the  impurities  that  are  added  to  the 
air  by  reason  of  the  presence  of  human  beings  ;  (2)  to  have  some  means  of 
determining  the  presence  of  such  impurities,  and,  if  present,  their  amount ; 
(3)  to  fix  on  some  standard  of  ventilation,  or  limit  in  the  amount  of  impurities 
which  must  not  be  exceeded  in  an  air-space,  if  such  space  is  to  be  kept  in  a 
proper  and  wholesome  condition. 

It  will  be  convenient  to  consider,  first  of  all,  the  case  of  ordinary  dwell- 
ings occupied  by  healthy  persons,  and,  subsequently,  certain  special  condi- 
tions, as  those  of  schools,  factories,  and  hospitals. 

1.  The  impurities  present  in  an  air-space  that  are  due  to  the  fact  of  its 
being  inhabited  fall  under  the  three  heads  of  (A)  those  that  are  derived 
from  the  inhabitants  themselves  ;  (B)  those  that  are  produced  by  the  arti- 
ficial lighting  or  heating  of  the  chamber  ;  and  (C)  those  derived  from  the 
walls,  furniture,  &c.  of  the  room. 

A.  The  first  category  may  further  be  considered  under  the  two  divisions 
of  the  impurities  due  to  (1)  the  breath  and  (2)  the  perspiration. 

(1)  Impurities  due  to  the  Breath 

The  changes  that  take  place  in  air  that  has  been  respired  are  the 
following  :  {a)  the  temperature  is  raised  ;  (&)  consequently  the  volume  is  in- 
creased, but  if  the  inspired  and  expired  air  be  measured  at  the  same  tempera- 
ture and  pressure  there  is  a  diminution  in  volume  ;  (c)  there  is  an  increase 
in  the  watery  vapour  ;  {d)  also  an  increase  in  the  carbon  dioxide  ;  {e)  nitrogen 
and  (J)  ammonia  ;  [g)  the  oxygen  is  diminished ;  {h)  there  is  an  addition  to 
the  air  of  hydrogen  ;  {i)  marsh  gas  ;  and  {h)  organic  matter.  Of  these  several 
alterations  in  the  composition  of  the  air  the  increase  in  the  carbon  dioxide 
and  watery  vapour,  and  the  addition  of  organic  matter,  are  the  most  important 
from  a  hygienic  point  of  view. 

The  composition  of  expired  air  by  volume  may  be  stated  as — 


Per  cent. 

Oxygen 

.     16-033 

Hydrogen           .         .     trace 

Nitrogen 

.     79-557 

Methyl  hydride  (CH^)    trace 

Carbon  dioxide  (COo)    . 

.      4-380 

Aqueous  vaiDour.         .     nearly  to 

Ammonia  (NH3)  . 

traces 

saturation 

(i)  Carbon  Dioxide 

The  amount  of  CO2  exhaled  in  respiration  has  been   investigated  by 

numerous   observers,  the   quantity  estimated  varying  from  31 '5  grammes 

(Ranke)  to   37'5  grammes  (Vierordt),  equalling  0'56   to  0*67   cubic  foot, 

every  hour.      There   are  very  many  influences   at  work  to   cause  varia- 


14 


HYGIENE 


tion,  and  the  methods  of  estimation  and  apparatus  required  are  delicate 
and  complicated  ;  the  determination,  therefore,  is  a  matter  of  some  difficulty. 
The  observations  of  Petteukofer  may  be  taken  as  being  exceedingly  accurate 
and  trustworthy.  He  found  that  a  man  aged  twenty-eight  years,  weighing 
132  lb.,  evolved  hourly  in  complete  repose  during  the  night  0*56  cubic  foot,  in 
gentle  exertion  during  the  dayO"78  cubic  foot,  in  hard  work  during  the  day  1*52 
■cubic  foot.     These  figures  give  in  round  numbers  respectively— 

In  complete  repose  during  the  night    .     -004  cubic  foot  C0._.  per  lb.  of  body-weight 
In  gentle  exertion  during  the  day         .     "000  „  „ 

In  hard  work  during  the  day        .         .     •012  ,,  „ 

Taking  now  the  average  weight  of  adult  males  as  150  lb.,  of  adult  females 
as  100  lb.,  and  of  children  as  75  lb.,  and  again  using  round  numbers,  these 
figures  give  the  following  data  : — 

Average  hourly  Excretion  of  CO.,  by  Lungs,  in  cubic  feet 


^-•ePose              I^I-^Jf 

In  hard  work 

Adult  males  . 
Adult  females 
Children 

•6 
•4 
•3 

•90 
•60 

•45 

1^8 
1-2 
0-9 

The  influences  that  modify  the  excretion  of  CO.2  are  chiefly  the  following  : 
(1)  Age. — The  amount  is  increased  up  to  about  thirty  years  ;  it  remains  station- 
ary from  thirty  to  forty-five  ;  after  forty-five  years  it  diminishes.  (2)  Sex. — 
After  eight  years  males  give  off  considerably  more  than  females  (according  to 
Andral  and  Gavarret  this  increase  is  about  one-third).  (3)  Development. — 
More  CO2  is  given  off  by  the  vigorous  and  robust  than  by  the  slender,  this 
increase  being  more  proportionate  to  the  muscular  development  than  to  mere 
size  and  weight  of  the  body.  (4)  Sleep. — Less  CO2  is  evolved  during  sleep  than 
when  lying  awake  and  at  rest.  (5)  Food  and  fasting. — Abstinence  diminishes, 
and  the  taking  of  food  increases,  the  evolution  of  CO2,  the  amount  of  increase 
varying  with  the  nature  of  the  food.  (6)  Muscular  exertion  greatly  increases 
the  CO2  given  off.  (7)  The  temperature  of  the  surrounding  air,  (8)  the  time 
of  day,  and  (9)  the  season  of  year  all  exercise  an  influence,  the  excretion 
being  increased  by  cold,  about  the  middle  of  the  day,  and  in  the  spring  ;  and 
decreased  by  heat,  about  midnight,  and  in  the  autumn. 

It  is  evidently,  therefore,  a  matter  of  great  difficulty  to  determine  the 
amount  of  carbon  dioxide  habitually  given  off  by  an  average  population,  on 
account  of  these  numerous  sources  of  modification  ;  and  any  attempt  at 
stating  a  normal  or  standard  amount  must  be  accepted  as  admitting  of  varia- 
tion within  very  wide  limits.  In.  repose  '  for-  a  mixed  community  a  general 
average  of  -6  cubic  foot  per  hour  may  be  adopted  '  (Parkes  and  de  Chaumont) ; 
and  it  should  be  borne  in  mind  that  (1)  for  muscular  adult  males  a  higher 
figure,  -7  or  -72,  should  be  taken  ;  and  (2)  that  children,  although  evolving 
a  less  amount  absolutely  than  adults,  give  off  relatively,  in  proportion  to 
their  body-weight,  nearly  twice  as  much. 

(ii)  Aqiieous  Vapour 

Whatever  be  the  hygrometric  state  of  the  atmosphere,  the  expired  air  is 
nearly  saturated  with  moisture.  The  absolute  amount  thus  added  to  the 
atmosphere  varies  with  (1)  the  temperature  of  the  expired  air  and  (2)  the 
quantity  of  watery  vapour  already  existing  in  the  air  before  it  was  respired. 
The  temperature  of  expired  air  varies  only  within  narrow  limits  ;  it  is  usually 


AIB  15 

higher  than  that  of  the  surrounding  atmosphere,  but  may  he  lower ;  it  ia 
sh'ghtly  below  the  blood  temperature,  being  about  93°  F.  to  97°  F.  According 
to  Pettenkofer  and  Voit,  at  a  temperature  of  59°  F.,  and  the  relative  humidity 
of  the  air  being  75  per  cent,  of  saturation,  an  adult  gives  to  the  air  10- 19  oz. 
(286  grammes)  of  watery  vapour  in  twenty-four  hours.  Other  observers 
estimate  the  amount  as  from  200  to  300  grammes  f about  7  to  11  oz.j ;  according 
to  Valentin  it  is  as  much  as  640  grammes  (22'5  oz.) 

(iii)  Organic  Matter 

The  nature  of  the  organic  matter  given  off  by  the  lungs  has  not  been  pre- 
cisely determined :  it  is  odorous  and  putrescible  ;  it  decolorises  solution  of 
permanganate  of  potash,  and  is  therefore  oxidisable  ;  it  also  yields  ammonia, 
and  is  therefore  nitrogenous.  It  is  doubtless  of  a  mixed  composition,  mole- 
cular rather  than  gaseous  ;  and,  in  addition  to  substances  derived  from  the 
lungs,  the  breath  contains  particles  of  epithelium  and  fatty  mattei's  from  the 
mouth  and  pharynx,  and  in  some  cases  organic  effluvia  from  the  stomach. 

Neither  has  the  amount  of  this  complex  organic  matter  been  exactly 
estimated.  Carnelley,  Haldane,  and  Anderson  made  some  careful  experiments 
(too  few,  however,  to  warrant  a  general  deduction),  in  which  the  excess  of 
oxidisable  matter  in  the  expired  air  over  that  present  in  the  room  was  found 
to  vary  from  1*7  to  13*6,  giving  an  average  for  one  observer  of  7*6  and  for 
another  8*3,  These  figures  are  volumes  of  oxygen  required  to  oxidise  the 
oxidisable  matter  per  million  volumes  of  air.  The  amount  is,  therefore,  by 
no  means  constant,  and  the  range  of  variation  is  so  wide  that  the  averages 
are  not  of  much  value. 

(2)  Imjmrities  due  to  Perspiration 

The  matters  derived  from  the  cutaneous  secretion  are  both  organic  and 
inorganic  :  the  chief  are  water,  sodium  chloride,  and  other  inorganic  salts  in 
small  quantity,  various  fatty  acids,  neutral  salts,  and  ammonia  (urea)  ;  in 
addition  particles  of  epidermis  constantly  become  detached  and  float  off  into 
the  surrounding  atmosphere.  The  quantity  of  perspiration  thus  given  off  is 
large,  but  very  variable  :  about  2  lb.  (or  900  grammes)  of  fluid  during  the 
twenty-four  hours  (Seguin)  may  be  taken  as  an  average,  containing  1*8  per 
cent,  of  solids,  of  which  1*2  per  cent,  are  organic  substances. 

B.  Impueities  due  to  Combustion 

(1)  The  products  of  the  combustion  of  coal  are  carbon,  carbon  dioxide 
and  monoxide,  sulphur,  sulphur  dioxide  and  sulphuric  acid,  ammonium 
compounds,  and  water.  "Wood  gives  rise  to  carbon  dioxide,  carbon  monoxide, 
and  water.  As  these  substances  commonly  pass  out  into  the  outer  air,  they 
do  not  require  further  mention  in  this  place. 

(2)  The  substances  resulting  from  the  combustion  of  coal  gas,  oil,  and 
candles  are  usually  diffused  more  or  less  through  dwelling  rooms,  although 
they  can,  and  should,  be  carried  off  by  suitable  means,  and  the  air  thereby 
freed  from  a  very  considerable  amount  of  impurity.  The  chief  products  of  the 
combustion  of  average  coal  gas  are  nitrogen  (67  per  cent.),  water  (16  per 
cent.),  carbon  dioxide  (7  per  cent.),  carbon  monoxide,  if  the  combustion  be 
imperfect  (5  or  6  per  cent.),  sulphurous  acid,  and  ammonia.  One  cubic  foot 
of  gas  will  unite  with  from  about  1  to  If  cubic  foot  of  oxygen,  according 
to  its  quality,  requiring,  therefore,  from  about  5  to  8  cubic  feet  of  air,  and 
producing  on  an  average  about  2  cubic  feet  of  carbon  dioxide.  An  ordinary 
gas  burner  burns  between  3  and  5  feet  per  hour. 


16  HYGIENE 

An  ordinary  oil  lamp  burns  about  150  grains  of  oil  hourly,  consuming 
the  oxygen  of  rather  more  than  3  cubic  feet  of  air,  and  producing  a  little 
more  than  half  a  cubic  foot  of  carbon  dioxide  ;  1  lb.  of  oil  requires  about  150 
cubic  feet  of  air  for  complete  combustion. 

A  candle  burning  320  grains  per  hour  produces  about  -4  cubic  foot  of 
carbon  dioxide  in  that  time  (Erismann). 

C.    lairUEITIES    DEEIVED    FROM    THE    WaLLS,    FlOORS,    &C. 

In  addition  to  the  matters  already  mentioned,  the  air  of  inhabited  places 
contains  sohd  particles,  not  derivable  from  either  of  the  sources  that  have 
just  been  considered.  Under  the  name  of  dtist  may  be  included  mineral 
particles,  vegetable  and  animal  d&bris,  and  dead  matter  blown  in  from  the 
outside,  or  derived  from  the  surfaces  of  floors,  walls,  furniture,  &c.  In  ordi- 
nary dwellings  this  dust  is,  unless  in  extreme  amount,  hygienically  of  little 
consequence.  But  either  attached  to  these  inert  particles  or  floating  freely 
are  great  numbers  of  living  micro-organisms,  which,  though  as  a  rule  harm- 
less to  the  healthy  inmate,  may  under  certain  circumstances  possess  the 
greatest  significance.  Carnelley,  Haldane,  and  Anderson  have  shown  that 
the  micro-organisms  do  not  come,  to  any  large  extent,  from  the  persons  pre- 
sent in  the  room,  neither  from  the  lungs  nor  from  the  skin  ;  they  must  there- 
fore come  from  the  room  itself.  They  are  found  in  greatest  number  in  houses 
that  are  old,  overcrowded,  and  dirty.  When  the  air  is  at  rest  they  rapidly 
fall  to  the  ground,  being  again  dispersed  throughout  the  room  when  the  air  is 
disturbed,  particularly  when  much  dust  is  raised.  These  minute  organisms 
belong  to  the  groups  of  moulds  [Hypliomycetes),  yeasts  (Saccharoimjcetes), 
and  bacteria  {Schizomycetes),  the  latter  being  much  the  most  numerous. 

2.  From  the  above  brief  summary  it  is  seen  that  the  air  of  inhabited 
rooms  or  confined  spaces  is  rendered  impure  by  the  addition  to  it  of  solid, 
liquid,  and  gaseous  matters,  both  inorganic  and  organic,  dead  and  living, 
some  derived  from  the  occupants,  some  from  the  means  used  for  warming 
and  hghting,  some  from  the  rooms  themselves.  The  question  has  now  to  be 
considered,  How  can  the  presence  of  these  impurities  be  detected  and  their 
amount  estimated  ? 

The  means  at  our  disposal  to  attain  these  objects  are  (1)  the  use  of  the 
senses  ;  (2)  physical  and  (3)  chemical  methods,  and  (4)  examination  by  the 
microscope,  with  which  may  be  included  cultivation  methods  for  the  detec- 
tion and  enumeration  of  micro-organisms. 

The  sense  of  smell  detects  an  excess  of  organic  matter  in  an  air-space,  as 
evidenced  by  the  closeness  or  offensive  odour  of  the  air  ;  hygrometers,  or  the 
wet  and  dry  bulb  thermometer,  show  the  amount  of  watery  vapour  present. 
The  carbon  dioxide  can  be  readily  estimated  by  shaking  up  known  quantities 
of  lime  or  baryta  water  and  air  and  comparing  the  alkalinity  of  the  liquid 
before  and  after  the  operation.  The  number  of  micro-organisms  present  and 
their  nature  can  be  estimated  by  aspirating  a  known  quantity  of  air  through  a 
suitable  apparatus,  and  preparing  cultivations  in  nutrient  gelatine. 

These  and  other  methods  are  described  subsequently  in  the  section  on  the 
Examination  of  Air. 

It  is  universally  agreed  that  the  organic  matter  given  off  by  the  lungs 
and  skin  is  the  most  noxious  of  all  the  impurities  present  in  the  air  of  an 
inhabited  space,  but,  unfortunately,  the  means  for  the  exact  determination 
of  its  amount  are  both  imperfect  and  difficult  of  application.  On  the  other 
hand  the  estimation  of  the  amount  of  carbon  dioxide  can  be  accomplished 


AIB  17 

with  great  ease  and  very  fair  accuracy.  Frora  the  numerous  experiments  in 
barracks  and  hospitals  conducted  by  several  observers  it  appears  that  the 
oxidisable  matter  present  in  air  (probably  organic),  as  shown  by  the  amount 
of  potassium  permanganate  deoxidised,  is  generally  in  proportion  to  the 
amount  of  carbon  dioxide  present  due  to  respiration.  The  late  Dr.  de 
Chaumont,  from  a  large  series  of  observations,  proved  that  the  amount  of 
organic  impurity  present,  as  shown  by  the  sense  of  smell  carefully  employed, 
increased  pari  passu  with  the  carbon  dioxide  of  respiration,  and  he  deduced 
certain  general  rules  from  this  coincident  increase.  Carnelley,  Haldane,  and 
Anderson  do  not  appear  to  have  found  so  close  a  connection  between  the 
organic  matter  and  the  carbon  dioxide,  and  none  at  all  between  the  carbon 
dioxide  and  the  number  of  micro-organisms.  For  the  present,  however,  de 
Chaumont's  researches  give  ample  justification  for  the  belief  that  a  com- 
parative estimate  of  the  organic  purity  or  impurity  of  an  air-space  can  be 
safely  made  from  a  determination  of  the  amount  of  CO2  present,  making 
allowance  for  the  quantity  of  CO2  in  the  external  air.^ 

3.  From  what  has  been  said  in  the  preceding  paragraphs  it  may  be 
stated  :  (1)  that  the  chief  impurity  in  an  inhabited  air-space  is  the  organic 
matter  evolved  in  respiration  and  perspiration  ;  (2)  that  the  amount  of  this 
present  may  be  estimated  relatively  by  determining  the  amount  of  carbon 
dioxide  present ;  (3)  that  the  amount  of  carbon  dioxide  evolved  by  individuals 
can  be  calculated,  not  exactly,  but  with  a  considerable  degree  of  accuracy ; 
therefore  (4)  the  condition  of  the  air-space  of  known  size  tenanted  by  any 
number  of  individuals  can  be  calculated,  as  regards  the  quantity  of  CO 2, 
at  the  end  of  one  or  more  hours ;  and  therefore  relatively  its  condition 
as  regards  organic  impurity ;  and  (5)  if  a  standard  amount  of  CO2  be  fixed 
on,  a  limit  which  should  not  be  exceeded,  we  may  ascertain  by  calculation 
the  quantity  of  fresh  air  that  must  be  supplied  in  order  to  restrain  the  CO2 
within  these  bounds,  and  therefore  relatively  prevent  the  organic  impurity 
from  exceeding  a  safe  and  wholesome  limit. 

This  standard,  or  limit,  has  been  fixed  by  Eoth  and  Lex,  and  by  de 
Chaumont,  as  0*6  per  1000  volumes ;  by  Pettenkofer  and  by  Carnelley, 
Haldane  and  Anderson,  as  1  per  1000  volumes  ;  by  all  observers  the  amount 
present  normally  in  the  atmosphere  has  been  taken  as  0*4 ;  therefore  the 
excess  over  this  natural  quantity  should  not  be  more  than  0'2  or  0'6  per  1000 
volumes  respectively.  Morin  and  Eanke  advocated  the  supply  of  fresh  air 
in  such  proportions  that  the  excess  of  COg  due  to  impurity  from  respiration 
should  not  exceed  0*33  per  1000  volumes. 

The  observations  of  de  Chaumont  have  been  generally  accepted,  and  for 
the  reasons  already  stated  they  may  be  received  with  confidence.  He  took 
as  the  standard  '  the  point  at  which  there  is  no  sensible  difference  between 
the  air  of  an  inhabited  space  and  the  external  air,'  as  determined  by  the 
sense  of  smell.  This  standard  may  not  be  easy  to  attain  in  every  case,  but 
it  is  better  to  have  a  high  standard  at  any  rate  to  aim  at.  As  perfect  purity 
of  air  in  a  confined  space  is  out  of  the  question,  one  must  be  content  with 
something  short  of  this,  but  as  a  theoretical  standard  the  condition  should 
be  such  that  no  unpleasant  smell  or  closeness  should  be  appreciable.  The 
temperature  and  the  relative  degree  of  humidity  have  an  influence  on  the 
readiness  with  which  smell  of  organic  impurity  is  perceived  ;  they  also  them- 

'  A  reference  to  de  Chaumont's  papers  in  the  Proceedings  of  the  Royal  Society  for 
1875,  No.  158,  and  1876,  No.  171,  will  show  the  extreme  care  taken  in  drawing  conclusiona 
from  the  different  series  of  observations,  and  a  mathematical  proof  of  the  close  approsima- 
tion  to  truth  of  these  conclusions. 

VOL.  I.  C 


18  HYGIENE 

selves  give  indications  as  to  the  efficienc}^  of  ventilation  or  the  reverse.  From 
de  Chaumont's  observations,  63°  F.  and  73  per  cent,  of  humidity  may  be 
taken  approximately  as  standards. 

Carnelley,  Haldane,  and  Anderson,  as  just  mentioned,  have  fixed  on  a 
lower  standard  of  purity,  that  is,  they  propose  a  higher  Hmit  of  COo,  viz. 
0*6  volume  per  1000  above  that  in  the  external  air.  They  also  propose 
2  volumes  per  million  of  oxygen  required  for  oxidation  as  a  standard  for  the 
'  organic  matter  '  (or  rather  the  '  total  oxidisable  matter.'  See  Analysis  of 
Am,  p.  23).  .The  number  of  micro-organisms  present  should  not  exceed 
20  per  litre,  and  the  ratio  of  bacteria  to  moulds  should  not  exceed  30  to  1. 

Some  such  standards  being  agreed  upon,  it  becomes  now  a  matter  for 
calculation  to  ascertain  the  quantity  of  fresh  air  that  must  be  supplied  in 
order  to  maintain  a  space  in  a  well-ventilated  condition. 


HOW   MUCH  FEESH   AIE   IS   EEQUHIED   TO   EEEP  AN  INHABITED 
AIR-SPACE   HEALTHY? 

1.  If  e  =  amount  of  CO2  exhaled  per  head  per  hour  in  cubic  feet, 

r  =  admissible  Hmit  of  CO.,,  due  to  respiratory  impurity,  stated 

per  cubic  foot, 
d  =  delivery  of  fresh  air  required  in  cubic  feet  per  head  per  hour, 

then  —  =  d. 

r 

Taking  '6  cubic  foot  as  the  average  amount  of  CO2  exhaled  in  repose, 
and  '2  per  1000  as  the  limit  of  respiratory  impurity,  that  is  "0002  cubic  foot^ 

=  3000  =  delivery  of  fresh  air  required  per  head  per  hour. 

In  this  formula  if  r  be  ratio  per  1000  instead  of  per  cubic  foot,  then  d 
will  be  in  thousands  of  cubic  feet,  thus  : 

•A 

—  =  3  thousand  cubic  feet. 
'A 

2.  If  r  =  admissible  limit  of  respiratory  impurity, 

Ti  =  respiratory  impurity,  stated  in  ratio  per  1000  of  CO2,  exist- 
ing in 
c  :=  air-space, 

d  =  dehvery  of  fresh  air  required  in  cubic  feet, 
then  (n-r)xc^^. 

r 

that  is,  as  the  admissible  limit  :  excess  of  existing  over  admissible  ratio 
: :  amount  of  air-space  :  amount  of  fresh  air  required.  Thus,  if  there  be  one 
person  in  a  cubic  space  of  1000  feet,  at  the  end  of  one  hour  the  CO2  exlialed 

wiU  be   -6    cubic  foot  =  -6    per    1000 :     then  ("6  -  -2)  x  1000  ^  ^OOO 

'A 

=  cubic  feet  of  fresh  air  required  during  the  first  hour. 

Again,  if  there  be  three  muscular  adult  males,  averaging  12  stone  in 

weight,  in  a  space  of  2000  cubic  feet,  and  the  CO2  evolved  =  3  X'7  =  2*1 

2'1 
cubic  feet,  which  in  a  space  of  2000  cubic  feet  =  -^  =  1'05  per   1000  =  r; 

j^^^  (l:55-:2)xJO0O^g50Oeubicfeet 

—  2838  cubic  feet  per  head  required  during  the  first  hour. 


AIB 


19 


After  the  first  hour  the  size  of  the  cubic  space  is  of  little  consequence  in 
most  cases,  the  amount  of  fresh  air  required  from  without  depending  on  the 
amount  of  CO2  exhaled.  In  the  example  just  given  2833  cubic  feet  per 
head  were  required  during  the  first  hour ;  after  this,  whether  the  cubic 

space  be  200  feet  or  2000  feet,  the  delivery  of  fresh  air  must  be  —  =  ^ 

=  3*5  thousands  =  3500  cubic  feet  every  hour. 

3.  In  formula  (l)if  ri,  the  observed  ratio  of  impurity,  be  substituted  for 
r,  from  the  condition  of  the  air  shown  thereby  may  be  calculated  the  amount 
of  fresh  air  supplied  and  utilised  : 

—  =  d  =  amount  of  fresh  air  that  has  been'  supplied  and  utilised. 

Thus,  if  the  CO2  due  to  respiratory  impurity  be  found  to  be  1*05  per 
1000,  the  CO2  exhaled  being  -7  cubic  foot  per  head, 

•7  •        • 

then  — --  =  -6  =  '6  thousands  =  666  cubic  feet  per  head  per  hour  supplied. 
1*05 

4.  To  calculate  the  probable  condition  of  an  air-space  to  which  a  known 
quantity  of  air  has  been  supplied : 

e 


Let  e  =  -6,d  =  3000  ;  then  ^    -  =  -0002  cubic  foot  CO2  per  cubic  foot  of 

air  =  '2 per  1000  (or  this  maybe  stated  as  _=  •2). 

o 


Again,  let  e  =  '7,  d  =  1200 ;  then 


1200 


=  00058  =  -58  per  1000  CO2. 


5.  If  the  figures  on  page  14  be  taken  as  fairly  representing  the  average 
weights  of  adults,  male  and  female,  and  children,  and  (in  round  numbers) 
the  quantities  of  CO2  excreted  hourly,  the  amount  of  fresh  air  required  will 
be  as  follows : 

Amount  of  Air  required  hourly,  in  cubic  feet. 


- 

In  repose 

In  gentle 
exertion 

In  hard  work 

Adult  males . 
Adult  females 
Children 

3000 
2000 
1500 

4500 
3000 
2250 

9000 
6000 
4500 

For  muscular  adults  weighing  over  12  stone — as,  for  instance,  navvies— 
a  larger  amount  would  be  required,  about  3600  cubic  feet  in  repose,  with  a 
proportionate  increase,  under  the  circumstances  of  light  and  hard  work. 

6.  Amount  required  for  lights.— -Fov  each  cubic  foot  of  gas  burnt 
Wolpert  has  calculated  that  1800  cubic  feet  of  air  should  be  suppKed, 
whereby  the  ratio  of  CO2  due  to  combustion  would  be  kept  down  to  about 
I'l  per  1000,  and  the  sulphur  dioxide  and  other  combustion-products  safely 
diluted.  Each  ordinary  gas  burner  would  require  from  5400  to  9000  cubic 
feet  of  air  per  hour.  Oil  lamps  and  candles  do  not  generally  require  a 
special  supply  of  air,  not  because  the  CO2  evolved  by  their  combustion  is 
less,  for  equal  illuminating  powers,  than  by  that  of  gas,  but  because  so  much 
more  gas  is  generally  burnt,  giving  more  light  and  heat,  and  causing  much 
greater  deterioration  of  the  air  of  the  room. 

c2 


20  HYGIENE 


HOW   MUCH  INITIAL   CUBIC   SPACE   OUGHT   TO   BE   PEOVIDED  FOR 

EACH  INMATE? 

The  amount  of  fresh  air  required  per  head  having  been  agreed  upon, 
according  to  the  foregoing  considerations,  the  answer  to  the  question  of  how 
much  cubic  space  is  needed  will  depend  on  the  ease  with  which  the  air  in 
the  air-space  can  be  renewed.  The  larger  the  room  the  less  frequently 
need  the  contained  air  be  displaced  by  fresh  air  from  outside ;  the  smaller 
the  room  the  more  often  must  this  change  take  place,  and  the  greater  difficulty 
is  experienced  in  doing  this  effectually  without  causing  draught.  In  an 
air-space  containing  1000  cubic  feet  per  head  the  air  needs  only  to  be 
changed  three  times  in  an  hour  to  provide  the  necessary  3000  cubic  feet ; 
but  if  the  space  is  not  more  than  500  cubic  feet,  obviously  six  changes 
per  hour  are  required  to  supply  the  same  quantity  of  fresh  air.  With  the 
best  mechanical  means  of  ventilation  even  this  can  be  effected  without  per- 
ceptible draught,  as  in  Pettenkofer's  experimental  room  at  Munich,  where 
2640  cubic  feet  are  drawn  hourly  by  a  steam  engine  through  a  space  of  424 
cubic  feet.  But  in  temperate  climates  and  under  ordinary  circumstances 
three  changes  per  hour  are  all  that  can  be  borne  ;  more  frequent  change 
than  this  produces  cold  currents  of  air  and  draughts.  Therefore,  for  sleep- 
ing apartments  generally,  1000  cubic  feet  per  head  should  be  allowed  ;  in 
the  case  of  children  and  old  people  so  large  a  space  is  not  necessary — 
probably  500  to  600  cubic  feet  would  be  sufficient.  These  dimensions  are 
higher  than  are  usually  allowed,  but,  as  Dr.  Parkes  says,  '  after  all,  the  ques- 
tion is,  not  what  is  likely  to  be  done,  but  what  ought  to  be  done ;  and 
it  is  an  encouraging  fact  that  in  most  things  in  this  world  when  a  right 
course  is  recognised  it  is  somehow  or  other  eventually  followed.' 

AMOUNT   OF  FEESH   AIE  AND   CUBIC   SPACE   EEQUIRED   IN 
HOSPITALS,    SCHOOLS,   &c. 

Hospitals. — It  would  naturally  be  expected  that  a  greater  quantity  of 
fresh  air  would  be  required  to  keep  the  air  of  a  sick-chamber  in  a  good 
condition  than  the  air  of  a  similar  room  occupied  by  the  healthy.  Dr.  de 
Chaumont's  observations  point  to  the  conclusion  that  about  one-fourth 
more  fresh  air  should  be  suppUed,  as  the  smell  of  organic  matter  was  quite 
distinct  in  hospitals  when  the  CO  2  due  to  respiratory  impurity  was  0'166  per 
1000,  as  against  0*208  per  1000  in  rooms  occupied  by  healthy  persons ; 
therefore  the  hourly  supply  should  be  4000  cubic  feet. 

The  cubic  space  should  be  increased  in  at  least  the  same  proportion, 
viz.  from  1000  to  1250  or  1300  feet.  The  impurities  derived  from  the 
bodies  of  the  sick  ought  to  be  removed  as  quickly  as  possible,  and  being  to 
a  large  extent  particulate,  and  therefore  not  removable  by  diffusion,  there  is 
all  the  greater  need  for  a  large  dilution  with  fresh  air  and  exposure  to  its 
oxidising  and  purifying  effects  ;  this  can  only  be  done  efficiently  with  ample 
cubic  space,  as  draughts  have  especially  to  be  avoided  in  the  case  of  sick- 
rooms. For  purposes  of  convenience  of  nursing  and  attendance  a  floor- 
space  of  100  or  120  square  feet  is  considered  desirable  in  hospitals  ;  with  a 
height  of  12  or  18  feet  this  would  give  from  1200  to  1500  cubic  feet. 
These  measurements  are  applicable  to  ordinary  cases  of  sickness  ;  in  certain 
cases  where  there  are  offensive  discharges,  and  in  cases  of  infectious  disease, 
especially  typhus  fever,  and  in  pyaemia,  a  much  larger  amount  of  fresh  air  must 


AIB  21 

be  supplied — 5000  or  GOOO  or  more  cubic  feet  hourly — indeed,  treatment  in 
what  is  practically  the  open  air  often  has  the  best  results. 

Schools. — The  amount  of  fresh  air  required  for  children  has  been  already 
stated,  p.  19 ;  of  course  this  requires  modification  according  to  age.  The 
cubic  space  provided  by  the  London  School  Board  is  130  cubic  feet  per 
head,  being  10  square  feet  of  floor-space  and  13  feet  of  height.  The 
Education  Department  of  the  Privy  Council  endeavour  to  secure  at  least 
80  cubic  feet  and  8  square  feet  for  each  unit  of  average  attendance  in  public 
elementary  schools  in  England.  Carnelley,  Haldane,  and  Anderson  found 
an  average  of  160  to  170  cubic  feet  per  head  in  the  Board  schools  of  Dundee. 
In  France  the  allowance  is  from  120  to  140  cubic  feet  per  head.  All  these 
dimensions  seem  smaller  than  would  theoretically  be  deemed  advisable  : 
with  200  cubic  feet  per  head  the  air  would  require  changing  six  times  per 
hour  to  keep  the  CO2  due  to  respiratory  impurity  down  to  0-25  per  1000  vols. 

f^  =  r,  :  =  -00025  GOo  per  cubic  foot.^ 

W  6  X  200  ^  ^  J 

The  headaches  and  other  symptoms  ascribed  to  over-pressure  in  Board 
schools  may  often  really  be  attributable  to  the  breathing  of  a  foul  atmosphere 
for  many  hours  in  succession.  In  the  Dundee  schools,  however,  that  were 
ventilated  by  mechanical  means,  the  above  observers  found  a  fairly  good 
condition  to  exist,  in  spite  of  the  small  cubic  space  ;  the  CO2,  however,  was 
high  (judged  by  the  standard  adopted  in  this  article),  averaging  -89  per 
1000  vols,  above  that  in  the  outside  air.  The  standard  proposed  by 
Messrs.  Carnelley,  Haldane,  and  Anderson  for  schools  is  0*9  vol.  CO2  per 
1000  above  outside  air,  2  vols,  of  oxygen  per  1,000,000,  and  20  micro- 
organisms per  litre. 

Factories. — The  special  circumstances  resulting  from  the  different  kinds 
of  operations  carried  on  in  different  factories  will  modify  the  general  rules 
that  have  been  laid  down  ;  in  a  great  many  cases  special  impurities  are 
added  to  the  air,  which  require  removal  by  special  means  in  order  ta 
maintain  a  wholesome  condition  of  the  air-space. 


MEASUEEMENT   OP   CUBIC   SPACE 

The  measurement  of  the  amount  of  cubic  air-space  in  any  room  or  in- 
habited place  may  be  conveniently  carried  oiit  as  follows  : — 

1.  If  the  room  be  square  or  oblong,  with  a  flat  ceiling,  the  cubic  space 
will  be  simply  the  three  dimensions  of  length,  breadth,  and  height  multiplied 
into  each  other.  If  the  room  be  circular,  or  of  irregular  form,  with  a  curved 
ceiling  or  with  irregular  projections,  the  rules  for  the  measurement  of 
circles  &c.  must  be  used.  Irregularly  shaped  places,  if  rectilinear,  can  be 
divided  into  triangles  and  then  measured  ;  or,  if  bounded  by  curved  lines, 
they  can  be  divided  up  into  segments  of  circles  &c. 

2.  The  room  having  been  measured,  all  recesses,  such  as  doorways, 
window-recesses,  &c.,  should  be  added  in. 

3.  All  projections,  such  as  cupboards,  solid  pieces  of  furniture,  &c.,  should 
be  deducted. 

4.  Deduction  must  be  made  for  the  cubic  space  occupied  by  the  inmates ; 
an  average  amount  of  space  so  occupied  by  adults  is  3  cubic  feet;  an 
approximate  rule  is  weight  in  stones  -^  4  =  cubic  feet  occupied. 

6.  In  the  case  of  bedrooms  deduction  must  be  made  for  bedding 
and  bed  furniture,  which  may  occupy  on  an  average  about  10  cubic  feet  for 
each  person. 


22  HYGIENE 

It  is  more  conveBient  to  make  the  measurements  in  feet  and  decimals  of 
a  foot  than  in  feet  and  inches. 

Mules  for  Superficial  Measurement. 
Area  of  circle       .        .  =  vrr^  =  3-1416  x  square  of  radius. 

„  =  , —  =  square  of  circumference  x  •0796. 

4- 

Circumference  of  circle    =  tt  2  r  =  31416  x  diameter, 

C 
Diameter  of  circle         .  =  _  =  circimiference  x  •3183. 

Area  of  ellipse      .         .  =!L  ^=  3-1416   x  ^  long  diameter   x   |    short 

diameter. 
Area  of  square     .         .  =  square  any  one  of  the  sides,  or,  multiply  one  side 

into  another. 
Area  of  rectangle  .         .  =  multiply  together  two  sides  perpendicular  to  each 

other. 
Area  of  a  triangle        .  =  base  x  h  height,  or  height  x  ^  base. 
To  find  area  of  any  rectilineal  figure  :  divide  into  triangles  and  take  the  sum 

of  their  areas. 

Area  of  segment  of  circles  (f  x  chord  x  height)  +  £H^^_2l^£^. 

2  X  chord 

Bules  for  Cubical  Measurement. 

Cube  or  solid  rectangle   =  length  x  breadth  x  height. 
Solid  triangle       .         .  =  section  area  of  triangle  x  height. 
Cylinder      .         .         .  =  section  of  area  of  base  x  height. 
Cone  or  pyramid         .  =  area  of  base  x  ^  height. 
Dome  .         .         .         .  =  area  of  base  x  f  height. 

A  *2 

Sphere         ,        ,        .  = or,  diameter  cubed  x  •5236. 

o 

Nearly  every  inhabited  space  can  be  divided  up  into  figures  which  can 
be  measured  according  to  the  above  short  rules.  For  instance,  a  bell  tent 
is  a  cone  resting  on  a  short  cylinder  ;  a  hall  with  a  semicircular  roof  is  a 
half  cylinder  resting  on  a  rectangle,  or  if  with  a  segmental  roof  it  must  be 
measured  as  a  solid  segment  of  a  circle. 

EXAMINATION   OF  AIR 

For  hygienic  purposes  we  can  obtain  much  information  by  considering 
the  subject  in  the  following  general  order  : — 

1.  By  the  senses. 

2.  Chemical  examination  of  the  constituents  of  air. 

3.  Microscopic  examination  of  the  suspended  matters  in  air. 

4.  A  study  of  the  micro-organisms  obtained  by  cultivation  from  air. 

Examination  by  the  Senses 

It  is  now  generally  admitted  that  it  is  the  organic  matter  in  air,  either 
suspended  or  in  the  form  of  vapour,  that  is  the  impurity  we  have  chiefly  to 
deal  with  in  inhabited  air-spaces,  and  that  it  is  this  which  gives  the  peculiar 
foetid  smell  so  disagreeable  on  entering  an  ill-ventilated  air-space.  It  seems 
also  certain  that  these  organic  products  are  in  some  way  closely  connected 
with  the  humidity. 


AIB  23 

Though  the  nature  of  this  organic  matter  varies  to  some  extent,  but  one 
fact  remains  clear — we  must  dilute  the  air  in  the  air-space  with  x)ure  air 
until  the  amount  present,  as  judged  by  the  sense  of  smell,  does  not  differ 
sensibly  from  the  external  air.  Fortunately  we  have  not  to  depend  on  this 
test  alone,  for  observations  show  that  the  amount  of  organic  impurity  in- 
creases pari  passu  with  the  carbon  dioxide  evolved  by  the  persons  &c.  inhabit- 
ing the  air-space.  Dr.  de  Chaumont,  who  was  the  first  to  formulate  a  definite 
rule,  adopted  as  a  standard  the  point  at  which  there  is  no  sensible  differ- 
ence between  the  air  of  an  inhabited  space  and  the  external  air  as  determined 
by  the  sense  of  smell.     This  he  reduced  to  four  orders  or  classes  as  follows  : 

1.  '  Fresh,'  or  not  differing  sensibly  from  the  outer  air. 

2.  '  Eather  close,'  indicating  the  point  at  which  organic  matter  becomes 
perceptible. 

3.  '  Close,'  indicating  the  point  at  which  organic  matter  becomes  decidedly 
disagreeable. 

4.  '  Very  close,'  organic  matter  offensive  and  oppressive,  indicating  the 
point  at  which  the  differentiation  by  the  senses  is  reached. 

From  the  analyses  of  the  different  classes  and  the  data  these  gave  the 
following  conditions  of  ventilation  were  arrived  at : — 

1.  '  Fresh  '  :  Temperature  about  63°  F.  Aqueous  vapour  shall  not  exceed 
4*7  grains  per  cubic  foot.  Carbon  dioxide  shall  not  exceed  the  amount  in 
the  outer  air  by  more  than  0*2  per  1000  volumes.     Ventilation  here  is  good. 

2.  '  Eather  close '  :  Vapour  in  a  cubic  foot  of  air  exceeds  4*7  grains. 
Carbon  dioxide  in  excess  over  outer  air,  ratio  reaching  0*4  per  1000  volumes. 
Ventilation  here  ceases  to  be  good. 

3.  '  Close '  :  Vapour  exceeds  4*7  grains  per  cubic  foot.  Carbon  dioxide 
in  excess  over  outer  air  to  the  amount  of  0"67  per  1000  volumes.  Ventilation 
here  begins  to  be  decidedly  bad. 

4.  '  Very  close ' :  Vapour  reaches  5°1  grains  per  cubic  foot.  Carbon 
dioxide  in  excess  over  the  amount  in  the  outer  air  beyond  0"9  per  1000 
volumes. 

Chemical  Analysis 

This  should  include  the  following  points  : — 

1.  The  amount  of  COg.     This  is  taken  as  a  measure  of  all  impurities, 

2.  The  amountofoxidisable  substances,  as  judged  by  the  amount  of  oxygen 
absorbed  from  a  standard  solution  of  potassium  permanganate. 

3.  The  amount  of  free  ammonia. 

4.  The  amount  of  albuminoid  ammonia. 

5.  The  amount  of  nitrous  and  nitric  acids. 

6.  The  presence  of  sulphuretted  hydrogen  or  any  of  its  compounds. 

7.  The  presence  or  absence  of  ozone. 

8.  The  amount  of  watery  vapour. 

1.  Estimation  of  Carbon  Dioxide 

For  its  determination  the  following  method,  introduced  by  Pettenkofer, 
is  the  one  usually  adopted  on  account  of  its  simplicity  and  practical  utility. 
A  glass  jar  or  vessel  capable  of  holding  about  one  gallon  is  taken,  and  its 
capacity  accurately  measured ;  this  is  best  done  by  filling  the  jar  with  water 
and  measuring  the  contents  by  means  of  a  litre  or  pint  measure.  Dr.  Angus 
Smith  recommends  extracting  the  air  from  the  bottle  by  a  bellows,  while 
Mr.  Wynter  Blyth  would  fill  the  jar  by  the  same  means.  In  the  latter 
method  there  is  always  great  danger  of  introducing  impurities.  Perhaps  the 
best  plan  is  to  fill  the  jar  with  clean  water  and  empty  it  in  that  part  of  the 


24  HYGIENE 

air-space  it  is  desired  to  examine,  taking  care  to  allow  it  to  drain  well.  When 
this  is  done  60  c.c.  of  caustic  lime  or  baryta  water  are  put  into  the  jar  and 
the  mouth  closed  with  an  mdia-rubber  cap.  The  vessel  is  then  slightly  tilted, 
first  on  one  side,  then  on  the  other,  so  as  to  allow  the  lime  or  baryta  water 
to  run  over  the  sides,  and  to  thus  facilitate  its  exposure  to  the  air. 

If  lime  water  is  used,  the  vessel  and  its  contents  should  be  allowed  to 
stand  for  six  or  eight  hours ;  but  if  baryta  water  has  been  selected,  a  much 
shorter  time  is  sufficient — less  than  an  hour. 

The  CO2  is  absorbed  by  the  lime  or  baryta  water,  and  the  causticity  of 
these  substances  is  lessened  in  proportion.  The  loss  of  strength  of  the  lime 
Avater  therefore  measures  the  amount  of  carbon  dioxide  present.  Freshly 
prepared  lime  water  is  perhaps  the  most  convenient,  and  the  indications 
given  with  it  are  sufficiently  accurate  for  all  purposes. 

The  causticity  of  the  lime  water  is  determined  by  means  of  a  solution  of 
crystalline  oxalic  acid,  which  is  made  as  follows  : — 

Lime.    Oxalic  acid. 
56     :     126    ::  1  :  x  =  2-25. 
K  therefore  2*25  grammes  of  oxalic  acid  are  dissolved  in  1  litre  of  distilled 
water,  we  have 

1  c.c.  =  2"25  milligrammes  of  oxalic  acid. 

1  c.c.  neutralises  1  milligramme  of  CaO,  forming  oxalate  of  lime. 

Take  30  c.c.  of  freshly  prepared  lime  water  and  exactly  neutralise  with 
the  standard  oxalic  acid  solution.  Several  *  indicators '  may  be  used  for 
determining  the  exact  point  of  neutralisation,  but  good  tin-meric  paper  is 
generally  the  one  most  available  ;  a  solution  of  phenol-phthalein  gives  very 
exact  indications ;  when  the  point  of  neutralisation  is  reached  the  pink 
colour  is  discharged.  The  milligrammes  of  lime  in  the  30  c.c.  are  equal  to 
the  number  of  c.c.  of  the  oxalic  acid  solution  used,  and  this  is  usually  between 
30  c.c.  and  40  c.c. 

After  the  lime  water  in  the  jar  has  absorbed  the  CO2,  30  c.c.  of  the  solu- 
tion are  taken  out  and  tested  with  the  standard  oxaUc  acid  solution  as  before ; 
the  difference  shows  the  milligrammes  of  lime  which  have  united  with  the 
CO2.  The  milligrammes  of  lime  must  be  converted  into  CO2  by  calculation 
of  the  proportion  between  their  molecular  weights,  then  the  CO2  converted 
into  cubic  centimetres  by  calculation  of  the  proportion  between  weight  and 
volume. 

In  measuring  the  total  capacity  of  the  jar  60  c.c.  must  be  deducted,  this 
being  the  space  occupied  by  the  hme  water  put  in.  State  the  capacity  in 
litres  and  decimals  ;  divide  the  c.c.  of  CO2  obtained  by  the  corrected  capacity 
of  the  jar  ;  the  result  is  the  c.c.  of  COg  in  a  litre  or  per  1000  volumes 
of  air. 

Example. — 

The  first  alkalinity  of  the  lime  water  was  for  30  c.c.     39"0 

After  exposure  in  the  jar 33*0 

Difference = milligrammes  of  lime    ....       6*0 

Multiply  by  factor  .......     '795 

4-770=totaI  c.c.'g 
of  CO2  in  jar 
Capacity  of  jar  ......  =4385 

Deduct  60  c.c.  for  space  occupied  by  Hme  water  60 

Net  capacity    . ^4325  c.c.  or 

4-325  litres. 
Then  4-770h-4-325  =  1'103  of  CO.  per  litre  or  volumes  per  1000. 


AIR  25 

The  factor  '795  is  obtained  as  follows.  The  milligrammes  of  CO2  are  ob- 
tained by  calculating  from  the  ratio  of  the  equivalents  of  lime  and  carbon 
dioxide. 

CaO  CO2  Mgm  of  CaO  Mgm  of  CO, 

66     :      44     ::  a  :  x; 

44 

therefore     x=a  x  --. 

06 

As  1  c.c.  of  CO2  at  32°  F.  weighs  1-9767  milligramme,  the  ratio  between 

volume  and  weight  is =-506. 

""         1-9767 

Therefore  a:  X'506=c.c.  of  CO^,.     As  GO  c.c.  of  lime  water  were  put  into 

the  jar  and  only  30  c.c.  taken,  the  result  must  be  multiplied  by  2.    Therefore 

we  have  ^^  x-506  x2=-795. 
56 

Corrections  for  temperature  must  be  made  if  this  deviates  materially  from 
82°  F.,  this  being  the  temperature  at  which  all  gases  are  measured.  If  the 
temperature  of  the  air-space  we  propose  to  examine  be  above  this,  the  air 
is  expanded,  and  we  shall  be  operating  on  a  smaller  quantity  by  weight  than 
at  the  standard  temperature.  If,  on  the  contrary,  it  is  below  32°  F.,  we 
have  a  larger  quantity  of  air  to  deal  with,  and  an  addition  or  subtraction  must 
be  made  accordingly.  This  correction  may  be  stated  as  1  per  cent,  for  every 
5°  F.  above  32°  F.;  the  factor  -795  is  only  true  for  the  temperature  at  32°  F. 
For  each  degree  of  temperature  there  is  an  increase  or  diminution  of  "002  in 
the  volume  of  air,  i.e.  "2  per  cent,  or  2  per  1000 ;  for  example,  1  htre  of  air 
at  32°  F.  =  1000  c.c.  This  will  expand  at  33°  F.  to  1002  c.c,  and  will  con- 
tract at  31°  F.  to  998  c.c. ;  so  that  if  we  are  working  at  a  higher  tempera- 
ture we  are  taking  up  less  air  by  weight  in  our  jar,  and  if  at  lower 
temperatures  more  air.  If,  therefore,  the  temperature  is  5°  F.  above  32°  F. 
add  1  per  cent.,  if  below  subtract  1  per  cent,  from  the  amount  found.  For 
example,  if  the  CO2  per  1000  volumes  =  -6433  at  a  temperature  of  55°  F., 
then  55°  -  32°  =  23°  /.  23  x  '2  =  4-6  per  cent,  to  be  added ;  that  is,  100 
volumes  become  104-6  volumes  when  raised  from  32°  F.  to  55°  F.,  or  1 
volume  becomes  1-046. 

Then :  1  :  1-046  :  :  -6433  :  x, 

or,  1-046  X  -6433  =  -6728  volume  per  1000. 

The  correction  for  degrees  Centigrade  is  -3665  per  cent,  for  each  degree. 
Correction  for  pressure  is  also  necessary  when  the  experiment  is  made 
much  above  sea-level,  or  when  the  barometer  reads  below  the  standard  height 
taken,  as  -^  inch  of  pressure  causes  a  difference  of  -26  per  cent.  The  stan- 
dard height  of  the  barometer  for  which  all  observations  are  corrected  is 
taken  at  29-92  inches,  or  760  mm. ;  for  example,  if  the  experiment  is  made 
when  the  barometer  reads  29  inches,  then 

29  :  29-92  ::  observed  CO2  :  corrected  CO2 ; 

or  if  the  barometer  reads  31  inches, 

31  :  29-92  ::  observed  CO2  :  corrected  CO2. 

Although  this  method  for  determining  the  CO2  in  air  does  not  give  quite 
accurate  results,  it  is  the  most  convenient  for  ordinary  use,  and  sufficiently 
accurate  for  all  practical  purposes. 

Dr.  Angus  Smith  has  proposed  a  very  simple  process  for  determining  ap- 
proximately the  amount  of  CO2  in  any  air-space.  It  is  found  that  a  certain 
amount  of  carbon  dioxide  is  required  to  cause  a  given  volume  of  Kme  water 
to  become  turbid.     Half  an  ounce  of  perfectly  clear  lime  water  when  shaken. 


26 


HYGIENE 


with  the  air  contained  in  a  bottle  of  20-63  oz.  capacity  does  not  become  turbid 
if  the  air  in  the  bottle  contains  only  0-3  per  1000  of  COo,  but  if  0-4  per  1000  be 
present  a  white  precipitate  is  produced.  A  bottle  of  15*16  oz.  capacity 
does  not  render  half  an  ounce  of  lime  water  turbid  when  the  air  contains 
0-4  per  1000  of  CO.,. 

Taking  this  point  of  '  no  precipitation  '  (temperatm-e  of  the  air  at  32°  F. 
and  pressure  29-92  inches)  with  half  an  ounce  of  hme  water,  which  should 
be  satm-ated  and  clear,  as  the  test  point,  and  varying  the  bulk  of  the  air 
shaken  with  it,  Dr.  Smith  arranged  his  process  which  gives  results  sufficiently 
close  for  ordinary  purposes.  In  the  foUowuig  table  are  given  the  results 
of  the  determinations  of  the  volume  of  air  contauiing  different  percentages  of 
carbon  dioxide,  that  half  an  ounce  of  lime  water  contaimng  -0195  gramme 
of  lime  will  bear  agitation  with  and  give  no  turbidity.  In  the  table 
allowance  is  made  for  the  space  occupied  by  the  half-ounce  of  lime  water. 


Size  of 

Size  of  bottle 

Volume  of  air 

Carbon 

Size  of 

Size  of  bottle 

Volume  of  air 

Carbon 

bottle  in 

in  cubic 

in  cubic 

dioxide  in  the 

bottle  in 

in  cubic 

in  cubic 

dioxide  in  the 

ounces 

centimetres 

centimetres 

ail  per  cent. 

ounces 

centimetres 

centimetres 

air  per  cent. 

20-63 

684 

671 

-03 

6-00 

170 

156 

•11 

15-60 

443 

428 

•04 

5-53 

157 

143 

•12 

12-58 

356 

342 

•05 

6-15 

146 

132 

-13 

10-57 

299 

285 

•06 

4-82 

137 

123 

•14 

9-13 

259 

245 

•07 

4-53 

128 

114 

•15 

8-05 

228 

214 

•08 

'      3-52 

100 

86 

•20 

7-21 

204 

190 

•09 

292 

83 

69 

•25 

6-54 

185 

171 

-10 

i      2-51 

1 

71 

57 

•30 

It  is  necessary  that  white  glass-stoppered  bottles  should  be  used,  and 
of  the  best  description.  The  lime  water  should  be  deHvered  into  the  bottles 
as  rapidly  as  possible  by  means  of  a  glass  pipette  measuring  the  exact 
quantity. 

2.  Estimation  ofOxidisable  Substances  in  the  Air. 

To  determine  these  a  definite  quantity  of  air  is  drawn  through  a  solution 
of  permanganate  of  potassium  of  known  strength,  and  the  amount  of  unde- 
composed  permanganate  observed  by  means  of  the  standard  solution  of 
oxalic  acid,  or  part  of  the  water  through  which  the  air  has  been  drawn  may 
be  used  for  the  purposes  of  examination  and  the  oxidisable  matter  in  it  be 
determined  by  Tidy's  process  (see  article  on  Water  Analysis).  This  latter 
process  includes  two  determinations :  viz.  one  finding  the  oxygen  absorbed 
in  fifteen  minutes  and  the  other  the  amount  taken  up  in  three  hours.  The 
experiments  are  carried  on  at  a  temperature  of  80°  F. 

Carnelley  and  Mackie  have  proposed  a  modification  of  the  permanganate 
process,  for  which  are  claimed  the  advantages  of  rapidity  and  simplicity  of 
execution,  as  well  as  a  higher  probability  that  the  organic  matter  is  fully 
absorbed.  The  solution  used  is  of  the  N  strength,  of  which  1  c.c.  =  -008  mgr. 
of  oxygen=-0056  c.c.  of  oxygen  at  0°  C.  and  760  mm.     It  is  usually  kept  of 

strength  and  diluted  as  required,  about  50  c.c. of  dilute  sulphuric  acid  (1  to  6) 


10 

N 


being  added  to  each  litre  of  the  weak  solution. 

The  air  is  collected  in  large  well-stoppered  jars  of  about  3*5  litres  capacity. 
Before  use  the  jars  are  drained  and  the  contained  air  extracted  by  pumping 
with  a  small  bellows  and  allowing  the  air  to  be  examined  to  flow  in  :  50  c.c.  of 
the  standard  permanganate  are  next  run  into  the  jar,  which  is  then  tightly 
stoppered  and  well  shaken  up  for  at  least  five  minutes  ;  25  c.c.  of  the  per- 
manganate are  afterwards  withdrawn  by  a  pipette   and  placed  in  a  glass 


AIB  27 

cylinder  for  comparison.  Both  are  next  diluted  up  to  about  150  c.c.  with 
distilled  water  and  allowed  to  stand  for  ten  minutes,  after  which  the  tints  in 
the  two  cylinders  are  compared.  Standard  solution  is  then  run  in  from 
a  burette  until  the  tints  in  both  cylinders  are  of  the  same  intensity  ;  usually 
from  |-  to  6  c.c.  are  required. 

The  amount  of  solution  added  from  the  burette  is  a  measure  of  the  bleach- 
ing effected  by  the  known  volume  of  air  in  half  the  permanganate  employed. 
This  multiplied  by  2  gives  the  total  bleaching. 

Example. — 25  c.c.  of  solution  from  a  3*5  litre  jar  in  which  50  c.c.  had  been 
used  required  3  c.c.  of  the  permanganate  to  bring  it  up  to  the  standard,  or 
the  whole  50  c.c.  would  have  required  3x2  =  6  c.c.  This  represents  the 
number  of  c.c.  of  standard  permanganate  bleached  by  3500  —  50=3450  c.c.  of 

air;  consequently  •——^=1"74  c.c.  is  the  bleaching  effected  by  1  litre  of  air. 

But  1  c.c.  of  standard  permanganate  solution="0056  c.c.  of  oxygen  ;  therefore 
1-74  X  '0056= '0097  c.c.  of  oxygen  is  required  to  oxidise  the  organic  matter  in 
a  litre  of  air,  or  9*7  volumes  of  oxygen  to  oxidise  the  organic  matter  in 
1,000,000  volumes  of  air. 

3.  Examinatio7i  of  the  Free  and  of  the  Albuminoid  Ammonia. 

The  estimation  of  the  nitrogenous  matter  in  the  air  is  of  importance,  as 
it  is  mostly  derived  from  the  dead  and  Uving  matter  existuig  in  the  air,  and 
is  useful  for  comparison  with  results  obtained  from  pure  air.  The  most 
convenient  plan  is  to  draw  the  air  through  a  series  of  wash  bottles,  each  con- 
taining 100  c.c.  of  pure  distilled  water,  by  means  of  an  aspirator  of  known 
capacity,  so  that  the  volume  of  air  passing  through  may  be  measured  ;  five 
bottles  are  generally  used,  and  these  are  connected  by  indiarubber  tubing. 
"When  a  given  quantity  of  air  has  passed  through,  the  water  in  the  several 
bottles  is  mixed  together,  and  the  free  and  albuminoid  ammonia  determined. 
The  results  are  calculated  in  milligrammes  per  cubic  metre. 

The  object  of  these  processes  is  to  get  a  measure  of  the  nitrogenous 
matter  present ;  both  give  useful  information,  but  they  are  not  always 
applicable,  as  it  is  difficult  to  complete  such  an  analysis  on  the  spot  and  the 
amount  of  apparatus  required  renders  several  consecutive  determinations  in 
a  series  of  rooms  impossible. 

4.  Nitrous  and  Nitric  Acids. 

A  part  of  the  water  through  which  the  air  has  filtered  may  be  used  for 
the  determination  of  these  acids.  To  estimate  the  quantity  of  nitrous  acid 
present  Griess's  method  may  be  employed. 

For  the  determination  of  the  nitric  acid  the  aluminium  process  (Schulze's 
modified  by  Wanklyn  and  Chapman)  is  perhaps  the  simplest. 

In  these  processes  for  the  estimation  of  the  organic  matter  in  air  the 
quantity  drawn  through  the  water  must  be  accurately  measured  by  a  pro- 
perly arranged  aspirator,  and  the  results  calculated  as  milligrammes  per 
cubic  metre  of  air. 

The  presence  or  absence  of  sulpMiretted  hydrogen  may  be  determined 
qualitatively  by  means  of  acetate  of  lead  papers  and  ammonium  sulphide  by 
paper  dipped  in  nitro-prusside  of  sodium. 

Ozone  is  detected  by  its  action  upon  potassic  iodide.  Strips  of  paper 
saturated  with  a  solution  containing  starch  and  iodide  of  potassium,  dried 
and  exposed  to  the  air  for  a  definite  period,  are  supposed  to  indicate  the 
amount  of  ozone  present.  Ozone  causes  a  blue  tint,  the  depth  of  which  is 
taken  as  showing  the  amount  according:  to  a  standard  scale  of  tints. 


28  HYGIENE 

This  is  not  a  very  reliable  test,  as  nitrous  acid  and  peroxide  of  hydrogen 
give  the  same  reaction  ;  hght,  humidity,  and  temperature  also  vary  the  reac- 
tion. 

The  hygrometric  condition  of  the  air  is  ascertained  in  various  ways  ;  by 
Daniell's  hygrometer  or  Regnault's,  which  is  somewhat  similar  in  principle, 
or  by  Dines'  hygrometer  (see  article  on  Meteorology).  In  the  army  the  wet 
and  dry  bulb  thermometers  are  used,  and  the  relative  humidity  corresponding 
to  all  ordinary  readings  of  the  wet  and  dry  bulb  thermometers  are  taken  from 
Glaisher's  Tables. 

Examination  of  Micro-organisms  in  Air. 

In  addition  to  the  suspended  matters  found  in  air,  already  referred  to, 
micro-organisms  are  also  present.  The  points  of  importance  to  note  with 
regard  to  them  have  reference  to  their  number,  growth,  mode  of  development, 
and  cultivation  in  nutrient  media.  If  air  is  drawn  through  Hesse's  tubes, 
or  if  plates  covered  with  sterihsed  nutrient  gelatine  are  exposed  to  the  air, 
the  aerial  organisms  are  deposited  on  the  surface  of  the  gelatine,  and  cultiva- 
tion gives  rise  to  a  colony  which  has  a  characteristic  appearance.  From 
these  colonies  further  cultivations  may  be  made  in  tubes  by  inoculation,  and 
the  process  repeated  as  long  as  it  may  be  deemed  desirable. 

Hesse  has  shown  that  when  a  room  is  left  quiet  the  micro-organisms 
settle  dowTi  and  leave  the  air  comparatively  free  from  them.  In  the  case  of 
dwelling-rooms,  generally,  micro-organisms  decrease  as  cubic  space  increases. 
One  very  important  point  has  been  already  noticed,  the  relation  of  bacteria 
to  moulds  in  various  kinds  of  air ;  the  purer  the  air  becomes,  the  more 
readily,  as  a  general  rule,  do  the  bacteria  and  moulds  become  equal.  The  ex- 
planation is  that  the  moulds  come  mostly  from  the  external  air.  When 
the  air  of  a  room  becomes  very  impure,  the  bacteria  increase,  while  the 
moulds  remain  unaffected. 

It  was  also  found  that  the  stirring  up  of  dust  altered  the  ratio.  The 
moulds  were  little  affected  while  the  bacteria  increased  :  the  reverse  is  the 
case  when  quiet  is  established,  as  the  particles  to  which  the  bacteria  are 
attached  settle  more  rapidly  than  the  moulds ;  this  is  due  to  the  relative 
lightness  of  the  moulds. 

The  cultivation  of  bacteria  in  solid  nutrient  gelatine  or  in  agar-agar,  after 
the  manner  of  Koch,  is  the  method  generally  adopted  in  air  analyses,  subject 
to  various  modifications.  Hesse  adopts  the  following  plan.  A  glass  tube  of 
0'7  metre  (28  inches)  in  length  and  "035  metre  (nearly  1^  inches)  in  diameter 
is  carefully  sterilised ;  into  this  some  nutrient  gelatine  is  introduced  in  a 
liquefied  state  and  spread  out  over  the  whole  of  the  inner  surface  of  the  tube 
by  turning  it  about  on  its  own  axis.  One  end  of  the  tube  is  closed  by  an 
indiarubber  cap,  with  a  small  glass  tube  passing  through  its  centre  ;  the 
other  end  is  furnished  with  two  indiarubber  caps,  the  inner  one  being 
perforated  ;  all  the  portions  of  the  apparatus  have  been  previously  sterilised. 
The  liquefied  gelatine  quickly  solidifies  and  forms  a  thin  layer  over  the 
inside  of  the  tube.  The  apparatus  is  set  working  by  removing  the  outer 
indiarubber  cap,  and  aspirating  a  known  quantity  of  air  through  the  tube  at 
a  slow  rate  (1  litre  in  three  minutes).  The  germs  present  in  the  air  sink  down 
and  subsequently  develop  in  the  nutrient  gelatine. 

Dr.  Percy  Frankland  recommends  aspirating  the  air  through  a  small 
glass  tube  in  which  are  two  plugs  of  sterihsed  glass-wool.  When  the  air 
is  aspirated  through  this  tube,  the  glass-wool  retains  the  germs,  and  these 
plugs  are   afterwards  introduced  into   a  flask   containing  melted  nutrient 


AIB  29 

gelatine  and  well  shaken  up.  The  gelatme  solidifies  on  the  sides  of  the  flask, 
and  the  colonies  can  be  examined  by  means  of  a  lens  through  the  glass. 
Powdered  sugar  may  be  used  in  place  of  the  glass-wool,  but  this  latter  mixes 
so  intimately  with  the  gelatine  that  it  is  found  not  to  interfere  in  any  way 
with  the  growth  or  perception  of  the  colonies.  The  gelatine  may  also  be 
poured  on  glass  plates  in  the  ordinary  way,  instead  of  being  allowed  to  sohdify 
within  the  flask,  and  if  further  cultivations  are  carried  on  this  is  by  far  the 
most  convenient  plan. 

Dr.  Greenleaf  Tucker,  of  Boston,  U.S.A.,  prefers  using  granulated  sugar  in 
a  very  narrow  tube. 

Dr.  Petri  employs  calcined  sand  as  a  filter  in  grains  of  "25  to  -5  milli- 
metre in  size  ;  there  are  two  such  filters,  each  3  centimetres  in  length,  kept 
in  position  by  small  wire  caps.  After  the  air  has  been  drawn  through  the 
sand  is  poured  on  to  a  glass  plate,  over  which  liquefied  gelatine  is  then  run, 
and  development  takes  place  as  in  ordinary  plate  cultivations.  It  is  impossible 
to  say  at  present  which  of  these  methods  is  the  best. 

The  method  of  cultivation  adopted  at  Netley  is  that  introduced  by  E. 
Koch  :  this  consists  of  cultivation  in  sohd  nutrient  gelatine.^  Glass-wool 
carefully  removed  from  the  tubes  by  a  platinum  needle,  which  has  been  pre- 
viously heated  to  redness,  is  introduced  into  a  test  tube  containing  Hquefied 
nutrient  gelatine.  This  is  then  poured  into  one  of  Petri's  small  dishes  (which 
has  been  sterilised)  and  in  a  few  minutes  becomes  solid.  The  micro- 
organisms adhering  to  the  glass-wool,  if  any,  being  fixed  in  a  solid  medium 
will  grow  in  the  places  where  they  have  been  fixed,  and  in  this  way  colonies 
of  bacteria  are  developed,  which  can  be  differentiated  from  one  another  by 
various  peculiarities  of  growth. 

The  enumeration  of  the  colonies  that  grow  on  gelatine  plates  has  been  carried 
out  by  Miquel,  by  Koch,  by  isher,  and  by  Percy  Frankland,  as  well  as  many 
other  observers.  The  numbers  are  generally  stated  as  per  cubic  metre  of 
air,  each  colony  resulting  from,  and  therefore  indicating  the  presence  of  so 
many  separate  forms.  It  has  been  shown,  however,  that  the  micro-organisms 
vary  enormously  in  number  according  to  locality,  temperature,  season  of  the 
year,  and  even  time  of  day.  One  point  that  appears  to  be  demonstrated  is  that 
the  smaller  the  number  of  organisms  present  the  purer  is  the  air  supply ;  the 
numbers  diminish  rapidly  with  elevation  above  the  ground  level,  and  after  rain. 

Dr.  A.  M.  Davies,^  who  has  devoted  much  time  to  this  subject,  advocates 
a  systematic  description  of  the  naked- eye  characters  of  the  different  kinds  of 
colonies  as  being  likely  to  afford  valuable  indications,  and  has  suggested  that 
they  should  be  described  under  the  following  heads.  The  distinction  between 
Cocci  and  Bacilli  should  be  noted :  then — 

A.  Those  that  Uquefy  gelatine : 

Their  colour,  presence  or  absence  of  a  deposit  and  its  colour,  presence  or 
absence  of  areola  round  the  hquefied  part  &c. 

B.  Those  that  do  not  liquefy  the  gelatine : 

I.  Colour,  Generally  whitish  or  yellowish  ;  it  may  be  milky  or  translucent 
(colour  absent) ;  pale,  bright  or  deep  yellow,  &c. 

II.  Form.  Circular,  nearly  circular,  oval  or  more  or  less  irregular, 
branching,  &c. 

"'  Prepared  by  extracting  half  a  kilogramme  (about  1  lb.)  of  beef,  finely  chopped  up,  with 
one  litre  (1|  pint)  of  water,  with  the  addition  of  10  grammes  peptonum  siccum,  5 
grammes  of  common  salt,  and  100  grammes  of  gelatine,  rendered  very  slightly  alkaUne 
with  carbonate  of  sodium,  filtered  and  sterilised  by  successive  boilings.  A  perfectly  clean 
and  transparent  medium  should  result,  solid  at  ordinary  temperatures.  This  is  kept  in 
test  tubes,  about  one  quarter  full,  closed  with  sterilised  cotton-wool. 

-  Army  Medical  De^artme7it  Beports,  vol.  xxx.  p.  348. 


30  HYGIENE 

III.  Disposition.  The  colonies  may  be  raised  above  tlie  surface  of  the 
gelatine,  or  they  may  be  flat,  or  excavated  in  its  substance,  or  cup-shaped. 

IV.  Surface.  This  may  be  either  moist  or  dry,  shining  or  dull,  or  waxy- 
looking,  &c. 

V.  Peculiarities.  Such  as  granular  appearance,  hard  or  soft,  &c. 

If  to  this  be  added  a  description  of  the  character  of  the  growth  in  different 
media  and  on  potato,  as  well  as  the  microscopic  examination  of  the  organisms, 
we  have  all  the  information,  short  of  inoculation  experiments  into  living 
animals,  at  present  at  our  disposal  from  which  to  draw  conclusions.  It 
certainly  appears  advisable  to  supplement  any  chemical  examination  of 
an  air-space  by  an  investigation  of  the  characters  of  the  micro-organisms 
present,  in  the  hope  that  as  our  knowledge  increases  in  this  branch  of 
scientific  research  we  may  obtaui  in  this  direction  that  mformation  which, 
in  many  cases,  chemical  analysis  seems  incapable  of  furnishing. 


WARMING  AND  VENTILATION 

BY 

W.  N.  SHAW,  F.E.S. 

LECTURER  ON  EXPERIMENTAL  PHYSICS  IN  THE  UNIVERSITY  OF  CAMBRIDGE 


33 


INTEODUCTION 

1.  The  closely  related  subjects  of  warming  and  ventilation  may  be  re- 
garded mainly  as  special  technical  departments  of  the  sciences  of  heat, 
hydraulics,  and  pneumatics.  In  dealing  with  problems  relating  to  the 
warming  of  buildings  we  have  primarily  to  consider  the  production  and 
distribution  of  heat,  and  with  problems  in  ventilation  we  are  primarily  con- 
cerned with  the  mechanical  processes  involved  in  the  motion  of  air.  But  the 
continuous  production  of  heat  requires,  as  a  rule,  a  continuous  supply, of  air, 
which  may  be  used  for  the  purposes  of  ventilation  ;  in  fact,  heat  is  one  of  the 
most  important  agents  in  ventilation,  and  the  distribution  of  heat  is  frequently 
dependent  upon  the  distribution  of  heated  air  or  heated  water.  Moreover, 
the  air  which  is  supplied  for  ventilation  often  requires  to  be  warmed.  It  is 
not  therefore  practicable  to  consider  the  two  subjects  separately,  but,  with  the 
view  of  arranging  the  facts  with  which  we  have  to  deal,  in  some  sort  of  order, 
we  shall  first  consider  some  of  the  most  important  points  in  the  production 
and  measurement  of  heat  and  the  effects  produced  by  heat  upon  the  physical 
properties  of  air  and  other  bodies,  and  then  call  attention  to  some  of  the 
fundamental  phenomena  observed  in  the  motion  of  air  and  other  fluids  before 
proceeding  to  the  discussion  of  actual  problems  in  warming  or  ventilation, 
or  both  combined. 

2.  Production  and  Mecosurement  of  Heat. — Heat  for  the  purposes  of  warm- 
ing is  mainly  due  to  combustion,  which  is  a  name  given  to  the  chemical  action 
which  occurs  when  the  oxygen  of  the  air  combines  with  such  substances  as 
wood,  coal,  oil,  or  coal  gas.  Such  substances  are  known  as  fuels,  of  which 
there  are  many  kinds,  solid,  liquid,  or  gaseous.  The  principal  constituents 
of  fuels  are  the  solid  element  carbon  and  the  gaseous  element  hydrogen,  and 
the  various  chemical  combinations  of  those  two  elements.  Under  certain 
conditions  the  fuel  unites  with  the  oxygen  of  the  air,  the  carbon  becoming 
oxidised  to  form  the  heavy  gas  known  as  carbonic  acid,  while  the  hydrogen 
also  becomes  oxidised  and  forms  water ;  the  oxidation  is  attended  with  the 
evolution  of  a  large  quantity  of  heat.  Thus  every  pound  of  carbon  in  burning 
forms  3'7  lbs.  of  carbonic  acid  gas  and  gives  out  enough  heat  to  raise  the 
temperature  of  87  lbs.  of  water  from  62°  F.  to  the  boiling  point  (212°  F.), 
while  every  pound  of  hydrogen  (190  cu.  ft.)  produces  9  lbs.  of  water,  and  in 
doing  so  gives  out  heat  enough  to  raise  417  lbs.  of  water  through  the  range 
of  temperature  from  62°  F.  to  the  boiling  point.  As  carbon  and  hydrogen 
form  the  main  constituents  of  fuel,  carbonic  acid  gas  and  water  are  the 
principal  products  of  combustion,  and  these  must  be  continually  got  rid  of, 
and  air  continually  supplied  to  furnish  a  continuous  supply  of  oxygen,  if  the 
combustion  is  to  be  maintained.  At  the  high  temperature  produced  by  the 
combustion,  the  water  is  produced  as  vapour  and  passes  away  with  the  car- 
bonic acid  gas  ;  it  may  be  diffused  through  the  air,  or  part  of  it  may  be 
condensed  if  the  products  of  combustion  be  sufficiently  cooled  before  they 
are  allowed  to  diffuse  into  the  outside  air. 

There  is  another  method  of  producing  heat  artificially  which,  though  not 
used  practically,  is  of  very  great  scientific  importance,  and  is  here  referred  to 

VOL.   I.  D 


34  HYGIENE 

especially  on  account  of  its  connexion  -with  the  converse  process,  the 
artificial  production  of  cold,  or,  to  speak  more  correctly,  the  artificial 
abstraction  of  heat  from  bodies  which  are  themselves  cold  in  comparison 
with  those  suiTOunding  them.  The  method  in  question  is  the  production  of 
heat  by  friction.  It  is  a  familiar  process  which  needs  no  description,  but 
what  is  important  to  our  subject  is  that  the  amount  of  heat  which  can  be 
produced  by  the  process  is  numerically  related  in  a  perfectly  definite  manner 
to  the  friction  which  produces  it  and  the  distance  through  which  the  rubbing 
surfaces  are  made  to  slide.  If  we  consider  a  large  flat  mass  lying  on  a 
horizontal  table,  and  dragged  along  the  table  by  a  weight  hanging  from  a 
string  passing  over  a  pulley  at  the  end  of  the  table,  and  if  we  suppose  that 
the  weight  required  to  keep  the  sliding  motion  just  going  is,  say,  100  lbs., 
then,  by  experiments  differing  in  detail,  but  not  in  principle,  from  the  ima- 
ginary one  here  described,  it  has  been  shown  that  for  every  foot  which  the 
100  lbs.  falls  a  certain  quantity  of  heat  is  produced  by  the  friction  and  divided 
between  the  table  and  the  mass  upon  it.  The  amount  of  heat  so  produced 
does  not  seem  large  when  compared  with  the  amount  of  heat  produced  in 
combustion ;  for  the  numerical  experiments  show  that  the  100  lbs.  would 
have  to  fall  through  7'72  feet  in  order  to  produce  heat  enough  to  raise  the 
temperature  of  a  pound  of  water  one  degree  Fahrenheit,  or  through  1158 
feet  to  raise  a  pound  of  water  from  62°  F.  to  the  boiling  point ;  a  pound  of  coal 
would  have  to  fall  under  similar  circumstances  through  upwards  of  2000 
miles  to  produce  the  same  amount  of  heat  by  friction  as  would  be  produced 
by  its  combustion.  The  falling  weight  is  said  to  lose  energy  in  falling,  and 
the  heat  produced  between  the  table  and  its  moving  load  is  the  equivalent 
and  representative  of  the  energy  so  lost.  The  energy  of  bodies  may  take 
many  forms  ;  that  of  a  raised  weight  is  one  form  only  ;  an  equal  amount 
might  have  been  furnished  by  stopping  a  mass  moving  with  a  sufficient 
velocity  or  by  allowing  a  compressed  spring  of  suitable  dimensions  to  resume 
its  natural  shape. 

Thus  heat  must  be  considered  as  one  of  the  many  forms  of  energy  and 
may  therefore  be  measured  as  energy  is  measured.  The  most  common  way 
of  measuring  a  given  amount  of  energy  is  to  estimate  how  much  '  work  '  it 
could  do.  If,  for  instance,  it  could  be  shown  that  the  energy  in  question 
would  Hft  a  10  lb.  weight  through  a  vertical  height  of  50  feet,  or,  what  is 
precisely  equivalent,  a  20  lb.  weight  through  a  height  of  25  feet,  the  amomit 
of  the  energy  would  be  10  x  50,  or  20  x  25,  i.e.  500  foot-pounds.  In  like 
manner  we  may  express  every  quantity  of  heat  as  so  many  foot-pounds.  This 
would  be  the  most  scientific  way  of  expressing  quantities  of  heat,  but  it  is  for 
several  reasons  not  practicable  to  employ  the  actual  conversion  of  heat  into 
work  to  furnish  a  working  method  of  measmdng  heat.  It  is  a  well-kno^^1l 
fact  that  if  we  were  to  set  about  measuring  the  heat  produced  by  the  burning 
of,  say,  a  pound  of  coal  by  finding  out  what  work  it  could  be  made  to  do  in 
lifting  weights  with  any  engine  or  apparatus  at  our  disposal,  at  least  nine- 
tenths  of  the  heat  would  escape  without  recording  itself  as  work,  though  the 
total  reconversion  of  the  remaining  one-tenth  into  heat  could  be  easily 
managed.  "While,  therefore,  we  should  not  lose  sight  of  the  fact  that  heat  and 
work,  or  energy,  are,  in  one  sense,  equivalent  terms,  and  that  when  work  is 
done  by  heat  a  certain  definite  amount  of  heat  necessarily  disappears,  and  vice 
versa,  yet  we  require  some  more  directly  applicable  way  of  measuring  heat 
than  by  finding  its  theoretical  work-equivalent.  The  practical  method,  as 
hinted  in  the  numerical  examples  given  above,  is  to  find  the  number  of  pounds 
of  water  that  can  be  raised  in  temperature  fi'om  32°  to  33°  F.  by  the  amount  of 
heat  to  be  measured.     We  shall  call  the  amount  of  heat  necessary  to  raise 


WARMING  AND   VENTILATION  35 

one  pound  of  water  through  that  range  of  temperature  the  lb.  F.  unit  of  heat, 
or  British  thermal  unit.  As  the  result  of  many  experiments  it  has  been 
shown  that  the  amount  of  heat  necessary  to  raise  the  temperature  of  1  lb. 
of  water  through  any  degree  of  the  scale  of  temperature  between  32°  F.  and 
212°  F.  is,  though  not  strictly,  yet  for  all  practical  purposes,  equal  to  the  lb.  F. 
unit ;  moreover  it  is  not  difficult  to  secure  that  all  the  heat  developed,  say, 
by  the  burning  of  1  lb.  of  coal  shall  be  devoted  to  raising  the  temperature  of 
a  weighed  quantity  of  water,  and  hence  we  may  express  that  heat  in  lb.  F. 
units  by  the  numerical  product  of  tlie  number  of  pounds  of  water  heated 
and  the  number  of  Fahrenheit  degrees  through  which  its  temperature  is 
raised.  V 

By  a  process  similar  in  general  principle  to  that  here  indicated,  the 
quantities  of  heat  produced  by  the  combustion  of  known  weights  of  different 
fuels  have  been  measured.  The  quantities  produced  in  the  combustion  of 
one  pound  of  the  commoner  fuels  are  given  in  a  table  on  p.  122,  and  the  same 
table  gives  an  estimate  of  the  amount  of  heat  that  can  be  bought  for  a  penny 
in  each  case.  The  quantity  of  heat  produced  by  the  combustion  of  a  fuel 
of  which  the  percentage  composition  is  known  can  in  general  be  approximately 
calculated  from  the  amounts  produced  in  the  burning  of  the  several  con- 
stituents ;  as  these  are  mainly  carbon  and  hydrogen,  the  most  important  data 
required  for  the  calculations  are  that  the  heat  of  combustion  of  one  pound 
of  carbon  is  13,000  lb.  F.  units,  and  that  of  one  pound  of  hydrogen  62,500 
such  units. 

3.  Latent  Heat. — As  a  general  rule  the  communication  of  a  quantity  of 
heat  to  a  substance  raises  its  temperature,  but  sometimes  the  effect  of  the 
transference  is  to  change  the  state  of  the  substance  without  altering  its 
temperature.  Thus  every  pound  of  ice,  when  it  melts,  absorbs  143  lb.  F. 
units  of  heat  without  any  rise  of  temperature  being  produced,  and  the  boiling 
away  of  a  pound  of  water  into  steam  in  the  air  is  only  secured  by  trans- 
ferring to  the  water  966  lb.  F.  units  of  heat,  although  the  temperature  of  the 
steam  will  be  the  same  as  that  of  the  water  from  which  it  is  produced.  The 
heat  is  then  said  to  be  rendered  latent,  and  the  amount  of  heat  rendered 
'  latent '  in  the  fusion  or  evaporation  of  1  lb,  of  any  substance  will  be  called 
the  latent  heat  of  fusion  or  evaporation,  respectively,  of  the  substance.  Water 
evaporates  at  all  temperatures  from  surfaces  exposed  to  the  air  unless  the 
air  is  already  saturated  with  water  vapour :  this  evaporation  takes  place 
at  the  sacrifice  of  the  latent  heat,  966  lb.  F.  units,^  for  each  pound  evaporated, 
which  if  not  drawn  from  a  special  supply  must  be  furnished  by  reducing  the 
temperature  of  the  water  itself  and  the  bodies  in  contact  with  it.  On  the 
other  hand,  a  cold  substance  in  very  moist  air  causes  a  condensation  of  the 
water  vapour  and  liberates  the  corresponding  amount  of  latent  heat. 

'  Other  practical  units  adopted  for  the  measurement  of  quantities  of  heat  are  as 
follows : — 

The  '  calorie '  is  the  amount  of  heat  required  to  raise  the  temperature  of  1  kilogramme 
of  water  from  0°  C.  to  1°  C. 

The  'therm,'  suggested  by  a  committee  of  the  British  Association  (B.  A.  Report  1888, 
p.  56),  is  the  amount  of  heat  required  to  raise  the  temperature  of  1  gramme  of  water  from 
0°  C.  to  1°  C. 

4200  Joules  =  1  calorie  =  1000  therms  =  3-968  lb.  F.  units. 
772  foot-pounds  =  1  lb.  F.  unit  =  -252  calorie  =  252  therms. 

2  The  latent  heat  of  evaporation  of  water  varies  slightly  with  the  temperatme.  It  may 
be  approximately  expressed  by  the  relation  L  =  1092  -  0-7  (T  -  32°)  =  966  -  07  (T  -  212°), 
L  being  the  latent  heat  and  T  the  temperature  Fahrenheit.  (Eankine,  Steam  Engine, 
§  214.) 

d2 


iJ6  HYGIENE 

4,  Specific  Heat. — The  amounts  of  lieat  which  can  be  stoi-ed  in  equal 
weights  of  different  substances  by  raising  their  temperatures  through  the 
same  range  are  very  different.  The  number  of  lb.  F.  units  of  heat  required 
to  raise  the  temperature  of  1  lb.  of  a  substance  through  1°  F.  is  called  its 
specific  heat.  We  give  here  a  table  of  the  specific  heats  of  some  substances 
by  which  it  will  be  easy  to  compare  the  efficiency  of  different  substances  for 
the  storage  of  heat. 

Table  I. — Specific  Heaxs 

Number  of  lb.  F.  units 
required  to  raiso  tlie 
temperature  of  1  lb. 
Substance  through  1°  F. 

Water 1 

Ice -504 

Steam  (ai  constant  pressure) -480 

„       (at  constant  volume) -STO 

Copper -0951 

Iron -114 

Brass -0939 

Fire  brick         -i 

Coal  and  Coke about  -2 

Wood    .         .  J 

Air  (when  the  volume  is  kept  constant)        .        .        .  0-169 
„    (allowed  to  expand  freely) 0-238 

From  this  table  it  appears  that,  weight  for  weight,  water  will  absorb  much 
more  heat  for  the  same  rise  of  temperature  than  any  of  the  other  substances, 
and  when  the  latent  heat  of  evaporation  is  added  we  find  that  by  carrying 
1  lb.  of  steam  at  212°  F.  into  a  room,  and  there  cooling  it  to  water  at  60°, 
we  should  have  transferred  1118  lb.  F.  units  of  heat,  whereas,  if  1  lb.  of  air 
were  similarly  dealt  with,  the  heat  got  out  of  it  would  have  been  a  very  much 
smaller  amount,  namely,  36  lb.  F.  units.  If  water  at  212°  F.  had  been  used, 
instead  of  steam  at  the  same  or  slightly  higher  temperature,  152  units  would 
have  been  developed,  or  about  four  times  as  much  as  for  the  same  toeight  of  air. 
"When  it  is  remembered  that  in  carrying  heat  from  place  to  place  by  carrying 
heated  bodies,  the  loss  of  heat  during  the  carriage  is  greater  the  higher  the 
temperature  to  which  the  heated  bodies  are  raised  (if  the  exposed  surfaces 
are  the  same),  the  comparative  economy  secured  by  using  water  instead  of 
air  for  the  purpose  will  be  sufficiently  obvious ;  and  yet  more  so  when  we  con- 
sider that  the  volume  occupied  by  equal  weights  of  air  and  water  at  212°  F. 
is  in  the  ratio  of  about  1000  to  1,  and  the  air  will  therefore  expose  nearly 
100  times  as  great  a  surface  for  the  same  weight. 

5.  Distribution  of  Heat. — If  a  number  or  '  system  '  of  bodies  at  different 
temperatures  be  left  to  themselves,  the  distribution  of  temperature  will 
gradually  become  uniform  by  the  passage  of  heat  from  the  hotter  to  the 
colder  parts  of  the  system.  The  process  of  distribution  of  the  heat  in  any 
special  case  would  ]probably  be  a  very  complicated  one,  but  it  may  be  analysed 
as  follows  : — 

i.  Distribution  by  Conduction. — The  hot  portions  will  communicate 
heat  to  the  cooler  layers  in  contact  with  them,  and  these  in  their  turn  will 
pass  on  heat  to  the  still  cooler  layers  adjacent,  taking  more  heat  from  the 
hotter.  In  this  way  a  slope  of  temperature  will  be  established  from  the 
hottest  to  the  coldest  portions,  and  the  rate  of  transmission  of  the  heat  will 
depend  on  the  steepness  of  this  slope  of  temperature.  The  process  of  dis- 
tribution in  this  manner  is  known  as  conduction  of  heat.  As  the  tempera- 
tures of  the  different  portions  become  more  nearly  equal,  the  slope  of 
temperature  becomes  less,  and  the  How  of  heat  consequently  slower.     With 


WARMING  AND   VENTILATION 


y,7 


the  same  slope  of  temperature  equally  thick  layers  of  different  substances 
allow  widely  different  quantities  of  heat  to  flow  through  them  in  equal  times. 
Good  conductors  are  such  as  allow  a  rapid  flow  of  heat  through  them,  and 
conspicuous  amongst  all  substances  in  this  respect  are  the  metals,  particu- 
larly copper.  Bad  conductors,  on  the  other  hand,  under  similar  circum- 
stances, allow  only  a  comparatively  slow  flow  of  heat  through  them.  A 
perfect  non-conductor  Avould  entirely  prevent  the  flow,  but  no  such  substance 
is  known  to  exist.  If  it  were  not  for  its  fluid  mobility,  air  would  be  a  very 
good  heat  insulator,  and  air  prevented  from  moving  about  by  some  substance 
such  as  cotton  wool  or  swan's-down  is  very  efficient  for  preventing  the 
escape  of  heat  from  hot  bodies.  Wood,  glass,  and  asbestos  are  also  very 
useful,  as  are,  too,  indiarubber,  wool,  felt,  fossil  meal  (Kieselguhr),  slag- wool, 
glass-wool,  paper.  The  loss  of  heat  from  steam  boilers  is  now  generally 
considerably  diminished  by  coating  them  with  a  thick  layer  of  some  badly 
conducting  composition. 

In  order  to  compare  the  properties  of  various  substances  with  regard  to 
their  power  of  conducting  heat  we  give  here  a  table  of  conductivities  or  con- 
ducting powers.  The  numbers  in  the  second  column  show  the  amount  of 
heat  in  lb.  F.  units  which  would  pass  per  hour  through  an  area  of  one  square 
foot  of  a  layer  of  the  substance  one  inch  thick  if  the  two  surfaces  of  the  layer 
differed  in  temperature  by  1°  F.  Except  for  copper  and  iron  the  data  are 
very  uncertain.  On  this  subject  authorities  differ  very  widely.  See  Everett's 
'  Units  and  Physical  Constants,'  §§  126-141 ;  and  Sir  W.  Thomson,  art. 
'  Heat,'  §  75,  Encycl.  Brit.  (9th  ed.)  The  amount  of  heat,  H,  flowing  per  hour 
through  an  area,  A  square  feet,  of  a  slab  I  inches  thick  of  a  substance  whose 
conducting  power  is  K  when  the  difference  of  temperature  is  t°  F.  may  be 

calculated  by  the  formula  H  =  K  -y-. 

Such  a  formula  may  often  be  usefully  employed  to  calculate  the  loss  of 
heat  through  walls  or  windows  with  a  view  to  determining  the  quantity  of 
heat  that  must  be  supplied  to  balance  such  losses,  and  so  keep  up  the  internal 
temperature  of  a  building.     See  Box's  Heat,  p.  212. 


Conducting  power 
in  lb.  P.  units.    (K) 

Substance 

Conducting  power 
in  lb.  P.  units.   (K) 

.     3225 

Water   . 

.      5-82 

477-4 

Air         .         . 

.        .       -16 

113? 

Wool     . 

•32 

16? 

Fossil  meal  . 

? 

4-3 

Glass     . 

.      6-6 

5-1 

Eider-down  . 

.       -31 

3-79 

Slag-wool 

.       -314 

es) 

1-70 

Asbestos  fibre 

? 

Table  II. — Conducting  Powers 

Substance 
Copper 
Iron 
Lead 
Slate 
Brick 
Firebrick 
Asphalt 
Oak  (across  the  fibres) 

ii.  Distribution  hy  Badiation. — When  a  hot  and  a  cold  body  are  separated 
only  by  certain  substances  which  may  be  called  transparent  for  heat,  the 
heat  passes  directly  (in  all  probability  in  the  form  of  waves  similar  to  waves 
of  light)  from  the  hot  to  the  cold  body,  only  a  very  small  fraction  being 
spent  in  heating  the  intervening  medium.  The  form  of  energy  which  the 
heat  assumes  on  its  passage  through  a  medium  in  this  manner  is  called 
'  radiation.' 

All  bodies  surrounded  by  transparent  media  are  always  radiating  heat 
which  may  be  absorbed  or  transmitted  or  reflected  by  the  bodies  upon  which 
it  falls,  precisely  in  the  same  way  as  light. 

Indeed,  physically  speaking,  light  is  but  the  name  given  to  a  special  form 


38  HYGIENE 

of  heat-radiation  which  the  construction  of  our  eyes  enables  us  to  see.  If  it 
falls  upon  an  opaque  body  some  is  reflected,  and  by  that  we  see  the  body, 
but  some  is  absorbed  and  raises  the  temperature  of  the  body.  Of  the  energy 
that  comes  from  a  glowing  body  only  a  small  part  is  visible,  the  greater  part 
bemg  only  appreciable  by  its  raising  the  temperature  of  the  body  by  which  it 
is  absorbed.  All  bodies  surrounded  by  transparent  substances  radiate  heat 
at  all  temperatures,  the  amount  of  heat  radiated  per  second  depending  upon 
the  temperature  in  some  way  which  is  not  yet  fully  understood.  It  depends, 
however,  also  on  the  nature  of  the  body  and  of  its  surface.  A  polished 
metallic  surface  radiates  very  little  heat  as  compared  with  a  dull  surface,  the 
amount  of  radiation  from  polished  metal  being  about  one-fifth  of  that  from 
lampblack,  white  lead,  or  any  other  dull  surface  at  the  same  temperature. 

The  power  of  a  body  to  absorb  radiation  is  the  same  as  its  power  of 
radiating  at  the  same  temperature  ;  so  if  two  bodies  radiate  heat,  each  to  the 
other,  the  transfer  of  heat  depends  on  the  difference  of  the  amount  radiated 
by  the  two,  and  this  will  be  affected  by  [a)  the  nature  and  surface  of  the 
radiating  body ;  (&)  the  nature  and  surface  of  the  absorbing  body  ;  (c)  the 
difference  of  temperature  between  the  two.  Speaking  generally,  we  may 
say  that  good  radiators  are  good  absorbers  ;  good  reflectors  are  bad  radiators  ; 
transparent  bodies  are  bad  radiators. 

The  most  familiar  and  important  instance  of  the  transfer  of  heat  by  radia- 
tion is  furnished  by  the  sun,  whose  rays  supply  us  with  heat  that  has  passed, 
as  the  motion  of  extremely  minute  waves,  through  tbe  ninety  millions  of 
miles  of  transparent  space  that  separate  the  sun  from  the  earth,  and  through 
the  earth's  transparent  atmosphere,  passing  on  its  way  through  strata  of  air 
that  must  be  colder  than  the  coldest  mountain-tops.  The  radiation  produces 
no  sense  of  warmth  until  it  is  converted  into  heat  in  the  bodies  upon  which 
the  rays  fall ;  and  from  what  has  been  said  above  it  will  be  clear  that  a  body 
in  the  sun's  rays  may  be  quite  cool  if  it  be  transparent,  and  if  opaque  its 
temperature  will  rise,  least  if  it  have  a  highly  polished  surface  and  most  il 
the  surface  be  dull,  particularly  so  if  it  be  dull  black.  It  is  a  common  enough 
observation  that  the  temperature  of  a  thermometer  which  has  its  bulb  coated 
Avith  lampblack  and  enclosed  in  an  exlaausted  glass  vessel  will  rise  on  ex- 
posure to  the  sun's  rays  to  a  point  not  far  short  of  the  boiling  point  of  water. 

Of  the  radiation  which  falls  upon  a  polished  surface  nearly  all  is  reflected 
like  light  from  a  mirror  :  from  a  polished  surface  of  silver  97  per  cent,  is  so 
reflected  ;  from  a  polished  steel  surface  83  per  cent.  If  the  surface  is  coated 
with  lampblack  nearly  the  whole  is  absorbed  and  applied  to  raising  the 
temperature  of  the  lampblack  and  the  substances  in  contact  with  it ;  but  if 
the  surface  be  dull  white  a  great  part  is  diffusely  reflected,  that  is,  the  radia- 
tion is  dispersed  in  all  directions  in  the  transparent  medium,  as  though  the 
white  surface  were  itself  rendered  very  hot  by  the  radiation.  In  this  way 
even  a  snow-field  by  diffuse  reflection  of  the  sun's  rays  may  produce  the 
same  effect  as  if  the  snow  itself  were  at  a  very  high  temperature.  If  the 
surface  upon  which  the  radiation  falls  is  in  any  degree  transparent,  the  radia- 
tion is  partly  transmitted,  partly  reflected  from  the  polished  transparent 
surface,  partly  diffusely  reflected  and  the  remainder  absorbed. 

Different  substances  exhibit  remarkable  differences  in  transparency  to 
radiation.  Air  if  dry  is  extremely  transparent,  but,  according  to  Tyndall,  the 
water  vapour  though  invisible  causes  considerable  opacity,  so  that  moist  air 
becomes  itself  heated  when  heat  is  radiated  through  it.  Of  other  transparent 
substances,  glass  is  the  only  one  which  is  of  great  interest  to  us,  and  its  pro- 
perties in  regard  to  radiation  are  exceptional.  A  plate  with  a  thickness  of 
"37  inch  absorbs  half  the  energy  of  radiation  which  falls  upon  it.  transmitting 


WABMING  AND   VENTILATION  39 

the  other  half ;  but  the  half  which  is  absorbed  consists  almost  entirely  of 
energy  in  an  invisible  form,  or  dark  heat,  as  it  is  called  ;  so  that  the  apparent 
effect  of  glass  in  shutting  out  light  is  very  small  indeed,  though  a  thick  plate 
is  very  effective  in  screening  the  heat  of  the  sun  or  fire. 

iii.  Distribution  by  Convection. — The  processes  of  distribution  of  heat  by 
conduction  and  radiation  are  frequently  rendered  much  more  rapid  by  the 
motion  of  the  liquids  and  gases  set  up  by  inequalities  of  temperature.  If  air 
is  in  contact  with  a  hot  surface,  it  becomes  itself  heated  by  conduction,  and 
therefore  specifically  lighter  than  the  surrounding  cooler  portions  ;  the  heated 
air  accordingly  rises,  being  pushed  upwards  by  the  sinking  of  the  colder  air. 
A  steep  slope  of  temperature  may  thus  be  maintained  and  the  flow  of  heat  from 
the  hot  body  greatly  accelerated.  This  process  also  takes  place  when  one  part 
of  a  liquid  ^  is  warmed  ;  but  as  any  liquid  is  specifically  so  much  heavier  than 
air  the  distribution  by  convection  is  not  so  easily  observed  in  liquids  as  in 
gases ;  but  it  always  exists  in  fluids  of  both  kinds  as  long  as  the  hotter  por- 
tion of  the  fluid  is  specifically  lighter  than  the  cooler  portion  above  it. 

The  convection  currents  in  any  closed  space,  as,  for  instance,  an  ordinary 
room,  are  in  consequence  enormously  complicated.  At  every  part  of  the  room 
where  the  air  is  being  heated  or  cooled,  no  matter  how  slightly,  unless  the 
heating  is  at  the  ceiling  and  the  cooling  at  the  floor,  convection  currents  are 
produced.  If  there  is  a  fire  in  the  room,  some  of  the  heat  of  the  fire  passes 
across  the  room  by  radiation  in  direct  lines  to  the  walls,  floor,  and  furniture 
without  directly  heating  the  air  to  any  considerable  extent.  The  surfaces 
upon  which  it  falls  absorb  part  of  the  heat,  communicate  heat  to  the  air  by 
conduction  in  consequence,  and  cause  upward  convection  currents  ;  other  parts 
of  the  heat  are  reflected  either  metallically,  as  by  a  polished  surface,  or 
diffusely,  as  by  a  dull  white  surface,  to  other  parts  of  the  room,  and  cause 
upward  currents  as  before.  On  the  other  hand,  the  windows  are  probably 
colder  than  the  internal  air  in  contact  with  them,  and  downward  convection 

■  currents  are  the  result.  The  sun's  rays  passing  through  windows  and  being 
absorbed  by  the  patch  of  floor  or  wall  upon  which  they  fall  cause  upward 
convection  currents.  Every  person  in  the  room  causes  convection  currents 
by  the  heat  conducted  to  the  air  in  contact  with  his  skin  or  clothes.  It  is 
easy  to  get  a  wind-vane  sufficiently  sensitive  to  show  the  convection  current 
due  to  the  heat  of  the  hand.  The  air,  therefore,  of  a  room  with  a  fire  in  it 
on  a  cold  day  is  in  a  most  complicated  state  of  turmoil,  as  an  examination  of 
the  motes  in   a  sunbeam   or  the  beam   of  an   electric   lamp  will  show. 

■  Convection  currents  produced  by  fires  in  shafts  and  chimneys  are  the  agents 
depended  upon  very  largely  for  causing  the  change  of  air  which  constitutes 
ventilation  in  mines  and  elsewhere,  and  success  in  ventilation  depends 
mainly  upon  an  accurate  knowledge  of  the  convection  currents  produced  by 
all  the  sources  of  heat  concerned,  whether  expressly  employed  for  the 
purposes  of  ventilation  or  not. 

The  convection  currents  produced  by  the  human  body  in  an  atmosphere 
colder  than  itself,  while  they  carry  off  a  good  deal  of  heat,  are  incidentally  of 
great  advantage,  as  they  provide  the  body  with  a  supply  of  fresh  air.  In 
climates  where  the  temperature  of  the  surrounding  air  is  so  nearly  that  of 
the  body  (98°  F.)  that  this  natural  replacement  of  air  does  not  take  place,  an 
artificial  commotion  is  necessary,  and  is  usually  made  by  means  of  fans  worked 
by  hand. 

Illustrations  of  the  great  complexity  of  the  convection  currents  in  a  room 
may  easily  be  obtained  by  observing  the  rapidity  and  the  uniformity  of  the 
>  distribution  of  odours  arising  from  Hquids  with  strong  smell,  or  from  tobacco 
'  Except  water  for  the  range  of  temperature  between  32°  F.  and  39°  P. 


40  HYGIENE 

smoke.  The  distribution  of  the  smell  is  accomplished  almost  entirely  by 
convection,  the  direct  efi'ect  of  diflusion  being  small  in  the  time  required  for 
the  approximately  iiniform  distribution  by  convection. 

Hardly  less  important  to  our  subject  is  the  convection  of  heat  in  liquids 
on  which  the  distribution  of  heat  by  hot  water  pipes  depends,  and  the 
comparative  uniformity  of  distribution  of  temperature  in  large  masses  of 
water  is  to  be  referred  mainly  to  the  same  cause.  The  principles  of  the 
action  of  convection  in.  liquids  and  in  gases  are  quite  identical,  the  differences 
in  detail  arising  from  the  relatively  greater  mass  of  the  liquid.  The  processes 
of  convection  of  heat  by  water  may  therefore  be  very  profitably  used  to 
furnish  analogues  in  ventilation  problems. 

0.  From  what  has  been  already  said,  it  will  be  seen  that  rapidity  or  slow- 
ness of  fall  of  temperature,  or  rate  of  cooling,  of  a  hot  body  surrounded  by 
cooler  ones  depends  upon  a  number  of  conditions  which  must  be  regarded  in 
designing  heating  apparatus  for  special  circumstances.  In  order  that  a 
body  may  cool  as  rapidly  as  possible,  its  specific  heat  should  be  small,  it 
should  be  a  good  conductor,  and  surrounded  by  cold  air  with  freedom  of 
motion,  and  its  surface  should  be  such  as  to  produce  the  greatest  possible 
radiation  of  heat.  An  iron  room,  painted  dead  black,  on  a  cold  clear  night, 
would  probably  offer  the  most  instructive  example  of  rapidity  of  cooling,  and 
conversely,  in  the  sun's  rays  it  would  become  most  rapidly  heated.  When 
we  desire  to  provide  for  the  health  and  comfort  of  the  inmates  of  a  building,, 
rapid  changes  of  temperature  are  generallyto  be  avoided,  if  possible,  andaroom 
with  thick  walls  of  brick  (whose  specific  heat  is  high)  surrounded  by  a  second 
wall  with  an  air-space  between,  and  painted  white  outside,  with  all  windows 
double  glazed,  and  a  thick  thatched  roof  or  double  roof,  would  satisfy  the 
conditions  required  for  maintaining  an  equable  temperature,  and  would  form  a 
striking  contrast  to  the  case  of  the  iron  room  previously  described.  On  a  small 
scale,  the  insulation  of  heat  is  carried  to  very  great  perfection  in  a  Norwegian 
cooking  stove,  which  consists  of  a  wooden  box  cased  inside  with  thick  layers 
of  felt  and  having  a  close  fitted  felted  lid.  The  hot  meats  are  kept  in  tins 
which  fit  closely  to  the  felt,  so  that  there  is  no  air  circulation.  The  tem- 
perature may  be  so  kept  up  by  the  heat  insulation  that  the  process  of  cooking 
can  go  on  for  some  considerable  time.  Thus  a  can  of  water  at  185°  F. 
placed  in  a  Norwegian  stove  required  twenty-nine  hours  for  its  temperature 
to  fall  to  104°  F.,  the  air  outside  the  box  being  at  68°  F. ;  whereas  the  tem- 
perature of  the  same  can  exposed  in  a  room  fell  through  the  same  range  in . 
seven  hours,  even  though  the  outside  air  was  slightly  warmer.  It  thus 
appears  that  the  loss  of  heat  may,  to  a  considerable  extent,  be  prevented  by 
suitable  arrangements. 

The  economy  of  fuel  by  the  prevention  of  loss  of  heat  from  houses  is 
a  department  of  our  subject  which  has  not  received  sufficient  attention  from 
architects  and  builders,  or  owners.  There  are,  indeed,  some  causes  of  loss 
of  heat  which  it  is  not  desirable  to  reduce  beyond  certain  limits.  A  great 
part  of  the  heat  of  an  open  fire  passes  up  the  chimney  with  the  products  of 
combustion,  but  a  considerable  part  of  this  is  effective  in  producing  the 
necessary  ventilation,  and  is  not,  therefore,  to  be  regarded  as  wasted,  and 
the  fireplaces  can  be  so  arranged  that  the  waste  from  this  cause  is  as  small 
as  is  consistent  with  the  adequate  efficiency  of  the  chimney  for  the  purposes 
of  ventilation.  On  the  other  hand,  the  heat  lost  by  conduction  through 
outside  walls  and  window-panes  is  merely  wasted,  and  has  to  be  made  up  by 
an  increase  in  the  quantity  of  fuel  consumed,  if  the  rooms  are  to  be  kept 
sufficiently  warmed.  And,  further,  permanently  damp  walls  are  a  continual 
cause  of  expense  in  fuel,  for  they  imply  a  continual  evaporation  of  water  ■ 


WABMING  AND   VENTILATION  41 

from  their  surface,  and  every  pound  of  Avater  so  evaporated  from  the  walls  of 
a  room  means,  with  an  ordinary  grate,  the  burning  of  an  extra  pound  of 
coal.  This  is  also  sheer  waste  of  heat,  and  is  now  prevented  in  the  bettor- 
class  houses  by  interposing  an  efficient  damp-course,  which  prevents  the  water 
passing  upward  from  the  ground ;  but  it  generally  goes  on  uninterruptedly 
in  smaller  houses,  although  the  increase  in  the  initial  outlay  need  not  be 
large,  and  the  economy  of  fuel  is  of  real  importance  to  the  tenants. 

The  loss  by  conduction  through  the  walls  and  windows  is  not  so  cheaply 
remedied.  Double  outside  walls  with  an  air-space  between  them  and  double 
glazed  windows  would,  no  doubt,  involve  greater  expense  than  would  be 
made  up  for  by  the  economy  of  fuel  that  would  result  from  their  use,  and 
they  are  therefore  only  introduced  where  an  equable  temperature  is  of  more 
importance  than  economy  in  building.  But  more  might  be  done  than  at 
present  in  placing  the  chimney  flues  of  houses  so  that  more  of  the  heat  that 
passes  through  their  sides  would  be  utilised  in  warming  parts  of  the  house 
instead  of  the  external  air.  Wooden  shutters  closed  at  night  would  help  to 
prevent  the  wasteful  loss  of  heat  by  conduction  through  the  glass  panes. 
There  is,  no  doubt,  a  general  prejudice  against  such  insulation  of  heat,  as 
we  have  been  used  for  so  long  to  rely  upon  the  crevices  of  the  vdndows  for 
the  supply  of  fresh  air  for  ventilation  ;  and  the  ventilation  is  even  then  so 
inadequate  that  we  have  acquired  the  habit  of  ventilating  a  room  when  it  is 
not  being  used  in  order  that  the  insufficiency  of  ventilation  when  in  use  may 
not  become  unendurable,  and  we  are  unwilling  to  interfere  with  our  small 
air  supply.  But  the  loss  of  heat  by  conduction  in  no  way  helps  the  ventila- 
tion, and  might  be  prevented  with  a  thoroughly  good  conscience  if  inde- 
pendent inlets  were  provided  for  the  purposes  of  ventilation. 


PHYSICAL   PEOPEETIES   OF   AIR 

7.  The  object  of  ventilation  maybe  stated  in  general  terms  to  be  the  con- 
tinuous replacement  of  the  vitiated  air  in  a  nearly  closed  space  by  '  fresh '  air. 
It  is  generally  considered  sufficient  to  draw  the  supply  of  air  from  any  position 
external  to  the  building  to  be  ventilated.  But  air  is  a  mixture  of  gases,  and 
may  contain  many  gaseous  compounds  as  impurity  ;  on  the  other  hand,  the 
mixing  of  air  in  open  places,  even  m  towns,  is  so  rapid  that  there  is  no  very 
great  difference  in  the  composition  of  the  air  drawn  from  different  locahties, 
unless  there  is  some  special  local  source  of  contamination  that  alters  the 
character  of  the  supply ;  thus  a  more  definite  meaning  is  attributable  to  the 
terms  *  air '  and  '  fresh  air  '  than  would  at  first  seem  likely. 

Fresh  air  we  may  take  to  be  a  mixture  of  gases  containing  20*96  per 
cent,  by  volume  of  oxygen  and  79  per  cent,  of  nitrogen,  with  -04  per  cent,  (by 
volume)  of  carbonic  acid  gas,  besides  a  quantity  of  aqueous  vapour  which 
varies  in  temperate  climates  between  0*5  grain  and  20  grains  per  cubic  foot 
of  air,  according  to  circumstances,  small  traces  of  ozone,  and  gaseous 
impurities  of  extremely  minute  amount.  Any  specimen  of  air  contains  also 
a  very  large  number  of  solid  particles  mechanically  suspended,  the  actual 
number  in  a  cubic  inch  varying  with  the  locality  and  the  state  of  the 
weather. 

8.  The  weight  of  a  cubic  foot  of  air  rendered  perfectly  dry  by  artificial 
means  varies  with  the  barometric  pressure  and  with  the  temperature. 
When  the  pressure  is  equivalent  to  that  of  30  inches  of  mercury,  and  the 
temperature  is  32°  F.,  the  weight  of  a  cubic  foot,  or  density,  of  dry  air  is 
666'9  grains  ;  enough  of  such  air  to  fill  a  room  of  1000  cubic  feet  capacity 


42  HYGIENE 

would  consequently  weigli  81  lbs.,  or  nearly  two-thirds  of  a  hundredweight, 
so  that  the  weights  to  be  moved  in  ventilation  are  not  inconsiderable. 

So  long  as  the  temperature  remains  the  same  the  density  is  proportional 
to  the  pressure,  so  that  a  fall  of  the  barometer  amounting  to  one  inch 
diminishes  the  density  of  the  air  by  about  one-thirtieth  part.  This  change  of 
barometric  pressure  may  arise  from  ordinary  meteorological  changes  or  in 
consequence  of  the  air  being  raised  to  a  height  of  900  feet  above  the  ground 
level.  We  may  express  the  law  relating  to  the  variation  of  the  density  of 
air  with  the  pressure,  considering  a  specific  mass  of  air,  by  saying  that  the 
volume  of  the  mass  of  air  is  inversely  proportional  to  the  pressure. 

When  the  pressure  is  kept  constant  and  the  temperature  changes,  the 
density  likewise  changes,  but  always  so  that  the  density  is  inversely  pro- 
portional to  the  number  of  Fahrenheit  degrees  in  the  temperature  with  459 
added  ;  thus,  increasing  the  temperature  from  the  freezing  point  (82°  F.)  to 
the  boiling  point  (212°  F.),  while  the  pressure  remains  at  30  inches,  will 
change  the  density  from  566-9  grains  per  cubic  foot  to  A ,  where 

^='^^^^459-^212' 
and  in  a  similar  manner  the  density  of  dry  air  at  any  other  temperature 
may  be  calculated.  Considering,  again,  a  specific  mass  of  air,  the  effect  of  a 
rise  of  temperatm-e  may  be  expressed  by  saying  that  the  volume  of  the  air 
will  be  increased  by  ^^i-fth  part  of  the  volume  at  32°  F.  for  every  Fahrenheit 
degree  rise  of  temperature. 

Combinuig  these  two  effects  of  pressure  and  temperature,  the  density,  A , 
of  dry  air  at  any  temperature,  t°  F.,  and  any  pressure,  B  inches,  is  given  by 
the  formula 

A  =  566-9  X  ^^  ^  f^l  +  f  ^  grains  per  cubic  foot       .     .     . '  (1) 
30       459  +  t 

9.  Dynamical  Cooling  of  Air. — One  important  case  of  variation  of  the 
density  and  temperature  of  air  under  special  conditions  requires  consideration  ; 
it  may  be  set  forth  in  the  following  way.  Suppose  that  a  room  had  been 
hermetically  closed  when  the  barometer  was  at  30  in.,  and  after  it  had  fallen 
to  29  in.  a  window  was  suddenly  opened ;  the  air  in  the  room  would  imme- 
diately expand,  part  being  forced  out  of  the  opening.  This  expansion  would 
be  unaccompanied  by  any  supply  of  heat,  and  the  pushing  of  the  external  air 
aside  by  the  internal  air  escaping  represents  the  performance  of  a  considerable 
amount  of  mechanical  work.  This  work  must  be  derived  from  some  source, 
and  it  would,  in  this  case,  be  obtained  by  the  conversion  of  some  of  the 
heat  contained  in  the  expanding  air  into  work,  and  would,  therefore,  be 
necessarily  accompanied  by  a  diminution  of  temperature  of  the  air.  The 
fall  of  temperature  produced  in  this  way  is  easily  observed,  and  is  known  as 
dynamical  cooling  of  the  air  ;  it  would  amount  to  nearly  5°  F.  in  the  instance 
mentioned.  The  conversion  of  heat  into  work  occurs  whether  the  expansion 
is  rapid  or  slow,  but  in  ordinary  slow  expansion  the  communication  of  heat 
from  surrounding  bodies  would  be  rapid  enough  to  prevent  the  thermometer 
falling  any  considerable  extent.  Compression  of  air  produces  a  corresponding 
heating  effect.  Whenever,  therefore,  expansion  or  compression  of  air  takes 
place  suddenly,  we  cannot  calculate  the  density  by  the  formula  (1),  because 
we  do  not  know  the  change  of  temperature  produced.  It  may,  however,  be 
shown  that,  under  the  circumstances  defined,  the  relation  between  the  initial 
and  final  pressures,  and  the  initial  and  final  densities,  is  expressed  by  the 
equation 


WABMING  AND   VENTILATION 


43 


whereas,  if  the  air  had  been  supplied  with  heat  rapidly  enough  to  compensate 

for  the  dynamical  cooling,  and  so  keep  the  temperature  constant,  the  relation 

would  have  been 

£==.^ 
p        A'' 

When  the  sudden  change  of  pressure  is  given,  the  change  of  density 

can  be  determined,  and   by  aid   of  equation  (1)   the  temperature  of  the 

suddenly  expanded  air  found.    To  exhibit  more  clearly  the  effect  of  dynamical 

cooling  the  following  table  has  been  compiled.     It  shows  the  density  and 

temperature  of  air,  of  which  the  pressure  has  been  reduced  to  30  in.  from 

the  number  of  inches  in  the  first  column  without  allowing  any  heat  to  be 

communicated  to  it  during  the  expansion. 

Table  III.— DyNAMicvii  Cooling  of  Aie  by  Eeduction  of  Pkessuke 
[Air  originally  at  60°  F.    Final  pressure  30  inches.] 


Initial  pressure 

Initial  pressure 

of  the  air  in 

Density  after 

Temperature 

of  the  air  in 

Density  after 

Temperature 

inches  of 

expansion 

after  expansion 

Inches  of 

expansion 

after  expansion 

mercury. 

mercury. 

Grs.  per  cu.  ft. 

Grrs.  per  cu.  ft. 

30 

536-3 

60-0 

60 

654-8 

-   33-9 

31 

541-4 

55-1 

70 

684-5 

-   52-4 

32 

546-3 

50-4 

80 

711-4 

-   67-7 

38 

551-2 

45-9 

90 

735-9 

-   80-8 

34 

556-0 

41-6 

100 

758-6 

-   92-1 

35 

560-6 

37-5 

200 

926-2 

- 158-5 

40 

582-6 

18-7 

300 

1040-9 

-191-6 

50 

•     621-3 

-11-0 

Thus  it  will  be  seen  that  if  a  jet  of  air  at  60°  F.  were  blown  into  a  room 
by  a  pressure  behind  the  jet  of  6^  inches  of  mercury  above  the  barometric 
pressure  of  30  inches,  so  that  the  pressure  of  the  air  of  the  jet  after  it  had 
issued  into  the  room  was  reduced  to  30  inches,  the  temperature  of  the  air 
would  be  32°  F.  if  we  neglect  the  heat  developed  by  the  friction  of  the  air  at 
the  nozzle.  In  any  actual  case  a  great  deal  of  heat  would  be  developed  by  the 
friction ;  indeed,  so  great  a  fraction  of  the  w^ork  equivalent  to  the  heat  con- 
verted would  be  reconverted  into  heat  by  friction  at  a  small  nozzle,  that  the 
cooling  effect  might  be  difficult  to  observe  ;  but  the  result  of  the  calculation 
is  sufficient  to  show  that  it  is  quite  possible  to  get  a  flow  of  cool  air,  even 
in  the  hottest  climates,  if  the  air  be  expanded  by  the  motion  of  a  piston  in  a 
cylinder  before  it  passes  into  the  room. 

We  have  supposed  that  the  air  is  practically  protected  from  heating 
during  expansion  by  the  rapidity  of  the  change  of  volume,  but  it  is  clear  that 
if  the  expansion  takes  place  in  an  enclosure  whose  sides  are  very  bad  con- 
ductors of  heat,  the  amount  of  heat  gained  by  conduction  will  be  compara- 
tively small,  even  if  the  expansion  be  slow.  Thus  it  is  possible,  by  means  of 
suitable  arrangements  of  expansion  cylinders,  to  furnish  a  supply  of  air 
cooled  by  expansion  to  a  temperature  considerably  below  that  of  sm-rounding 
bodies.  If  the  air  be  compressed  instead  of  being  rarefied,  a  correspond- 
ing rise  of  temperature  is  produced.  The  practical  appHcation  of  this 
principle  of  dynamical  cooling  to  the  refrigeration  of  ships  and  other  pur- 
poses will  be  considered  in  a  subsequent  section.  The  theory  of  it  is 
given  in  a  paper  by  the  late  J.  P.  Joule  in  the  '  Philosophical  Magazine,'  May 
1845,  p.  375,  '  On  Changes  of  Temperature  produced  by  the  Earefaction  and 
Condensation  of  Air  ' ;  and  the  suggestion  of  the  method  as  applicable  to  prac- 
tical problems  of  refrigeration  or  heating  will  be  found  in  a  paper  by  Sir  W. 


44  HYGIENE 

Thomson  ('  Glasgow  Philosophical  Society  Proceedings,'  vol.  iii.  Dec.  1852), 
or  still  earlier,  though  in  less  practicable  form,  by  Professor  Piazzi  Smyth 
('  Report  of  the  British  Association,'  1850). 

10.  Water  Vcqioiir.^ln  the  description  of  the  effect  of  changes  of  physical 
state  upon  the  density  of  air  no  reference  has  been  made  to  the  composition 
of  the  air,  nor  has  any  such  reference  been  necessary,  for  the  behaviour  of 
all  gases  and  mixtures  of  gases,  in  respect  of  change  of  physical  state,  follows 
the  same  laws,  unless  the  conditions  become  such  that  some  of  the  gas  con- 
denses to  a  liquid,  or  approaches  very  nearly  to  the  state  verging  upon 
condensation.'  The  only  constituent  of  the  atmosphere  for  which  such  a 
state  is  likely  to  be  reached  is  the  water  vapour,  and  it  is  on  this  account 
that  the  amount  of  water  vapour  in  the  air  is  liable  to  such  very  wide  variation. 
We  shall  subsequently  consider  the  evaporation  and  condensation  of  water 
in  detail  and  at  present  only  draw  attention  to  the  effect  produced  upon  the 
density  of  air  by  the  presence  of  the  water  vapour.  It  is  easy  to  calculate 
this  effect  when  the  pressure  of  vapour  in  the  air  has  been  measured  (see 
below,  §  12).  Regarding  the  weight  of  the  cubic  foot  of  moist  air  as  made  up 
of  dry  air  at  the  pressure  B  —  e,  and  w^ater  vapour  at  the  pressure  e,  we  get 
for  the  weight  of  dry  air  per  cubic  foot  from  formula  (1) 

^  '  I^t  ^^"^'^  ^''^''''- 

The  weight  of  water  vapour  may  be  takentobefths  the  weight  of  the  same 

volume  of  dry  air  at  the  same  temperature  and  pressure  ;  the  moisture  in  the 

5      e  491 

cubic  foot  will  therefore  be    -  .  ^  .  -r—^ 566'9  grains,  and  hence  the 

8      B     459  ^  i  " 

total  weight  per  cubic  foot,  or  the  density  A,  is  given  by  the  formula 

A  =  — ^^•'''^    .  — 56C"9  grains  per  cubic  feet. 

oO  459  +  t 

Moist  air  is  therefore  somewhat  lighter  than  dry  air  at  the  same  temperature 
and  pressure. 

11.  Effect  ofhii'puTity. —  The  effect  of  the  carbonic  acid  gas  in  the  air  upon 
the  density  of  the  mixture  is  hardly  appreciable.  The  density  of  CO.2  is  one 
and  a  half  times  that  of  air  (1*529),  so  that  replacing  one  volume  in  one 
thousand  of  air  by  carbonic  acid  gas  is  equivalent  to  including  in  the  space 
matter  which  will  increase  the  weight  by  -^J^-^jth  part.  This  would  have  been 
equally  well  secured  if,  instead  of  changing  air  for  COo,  the  air  had  been 
compressed,  so  as  to  increase  the  density  by  ao^oxr^^^  part,  or  if  the  temperature 
had  been  allowed  to  fall  sufficiently  to  produce  the  same  change  of  density. 
Thus  replacing  one  volume  per  thousand  of  air  by  carbonic  acid  gas  affects  the 
density  in  the  same  way  as  increasing  the  pressure  by  "015  inch  or  diminishing 
the  temperature  by  0-24'^  F. 

The  particles  mechanically  suspended  in  the  air  increase  the  density  by 
the  weight  of  the  particles  suspended  in  a  cubic  foot :  this  is  a  very  variable 
amount ;  in  mines,  according  to  Angus  Smith,  it  may  be  estimated  to  reach 
3  grains.  The  attention  of  scientific  men  has  recently  been  turned  to  these 
dust  particles  with  such  interesting  and  important  results  that  a  special 
chapter  will  be  devoted  to  its  consideration. 

Among  all  the  striking  properties  of  the  atmosphere  which  we  breathe  in 
the  open  air,  perhaps  the  most  conspicuous  is  the  uniformity  of  its  density, 
under  standard  couditioiis,  in  all  parts  of  the  globe  and  at  all  altitudes, 
arising  from  the  uniformity  of  its  composition,  as  already  alluded  to.  As  all 
the  changes  of  composition,  the  production  of  carbonic  acid  by  animal  life 
and  combustion,  and  the  absorption  of  carbon  and  elimination  of  oxygen  by 


WABMING  AND   VENTILATION  45 

plants,  take  place  at  the  surface,  and  in  very  different  amounts  in  different 
parts  of  the  globe,  the  uniformity  of  composition  is  very  remarkable.  .  The 
thorough  mixing  of  the  gases  is  due  to  the  process  known  as  diffusion,  whereby 
the  particles  of  each  of  two  gases  in  contact  gradually  permeate  the  space 
open  to  both,  and  in  a  certain  time  distribute  themselves  over  the  whole 
space,  each  as  if  the  other  were  absent.  The  process  of  diffusion  is  itself  a 
slow  one,  but  it  depends  on  the  area  of  surface  of  contact  of  the  gases.  This 
surface  of  contact  is  immensely  extended  by  the  mechanical  stirring  up  of 
the  gases  by  convection  currents,  and,  as  we  have  already  seen,  convection 
currents  are  practically  ubiquitous  agents  with  gases  of  identical  nature 
throughout ;  the  difference  of  density  of  the  gases  offers  another  cause  of 
currents,  so  that  the  mixing  of  the  gases  becomes  a  very  rapid  process,  and 
a  very  short  time  is  sufficient  for  the  uniform  diffusion  of  one  gas  over  a 
room,  unless  there  is  some  arrangement  which  especially  favours  separation. 
Escaping  coal  gas,  for  instance,  can  be  detected  all  over  a  closed  room, 
though  if  allowed  to  escape  in  large  quantity  its  specific  lightness  often 
results  in  the  formation  of  a  layer  of  much  stronger  gas -mixture  at  the 
ceiling. 

ON   WATEE   VAPOUR  IN   THE   AIR 

12.  We  have  already  stated  that  the  amount  of  moisture  contained  in  a 
gaseous  form  in  the  atmosphere  is  very  variable.  The  cause  of  the  variation 
lies  in  the  fact  that  conditions  frequently  occur  under  which  the  vapour  con- 
denses to  water,  and,  on  the  other  hand,  in  the  absence  of  these  conditions, 
evaporation  takes  place  from  every  exposed  water  surface  or  substance 
moistened  with  water.  The  phenomena  of  condensation  of  vapour  and 
evaporation  of  water  are  exhibited  in  nature  on  a  very  large  scale  in  the 
formation  of  rain,  fog,  and  mist,  and  in  the  disappearance  of  precipitated 
moisture,  respectively.  The  consideration  of  these  phenomena  belongs  to 
meteorology,  to  which  the  reader  may  be  referred  for  a  description  of  instru- 
ments for  determining  the  amount  of  moisture  in  the  air  (p.  164).  But  the 
conditions  of  evaporation  ajid  condensation  are  of  considerable  importance  to 
ventilation  and  warming,  for,  in  order  to  ensure  comfort  to  the  occupants, 
the  air  supplied  to  a  room  must  not  be  too  dry  nor  yet  too  moist. 

A  given  cubic  space  of  air  can  contain  only  a  certain  amount  of  vapour, 
dependent  upon  the  temperature  of  the  space  and  upon  no  other  condition ; 
the  presence  of  air  or  other  gases  in  the  space,  though  it  retards  the  evapora- 
tion of  water  into  it,  does  not  influence  the  ultimate  amount  of  vapour.  The 
evaporation  will  go  on  with  extreme  rapidity  if  there  is  very  little  air  pressure 
in  the  space — more  slowly  if  the  pressure  is  considerable — until  the  pressure 
of  the  water  vapour  itself  reaches  a  certain  limiting  value  called  the  satura- 
tion pressure,  which  depends  upon  the  temperature.  The  relation  between 
the  saturation  pressure  and  the  temperature  is  most  concisely  expressed  by  a 
curve,  the  vertical  height  of  a  point  of  which  shows  the  pressure  corre- 
sponding to  the  temperature  expressed  by  the  horizontal  distance  from  a 
zero  line.  Such  a  curve  is  shown  by  the  thick  line  of  fig.  1.  The  pressure 
is  given  in  hundredths  of  an  inch  of  mercury  and  the  temperature  in  Fahren- 
heit degrees. 

Air  which  contains  moisture  at  its  maximum,  or  saturation  pressm-e,  is 
said  to  be  saturated,  and  its  temperature  is  said  to  be  at  the  dew-point. 
Any  fall  of  temperature  or  slow  diminution  of  volume  determines  the 
deposition  of  moisture.  Most  frequently  the  saturation  point  is  passed  in 
consequence  of  a  gradual  fall  of  temperature,  arising  from  the  conduction  of 


46 


HYGIENE 


heat  away  from  the  air  by  the  soUd  bodies  in  contact  with  it ;  in  that  case 
the  condensed  moisture  is  deposited  upon  the  cold  surfaces,  and  the  air  may 
not  even  be  saturated  far  from  the  cold  surface.  The  condensation  of  an 
ounce  of  water  vapour  imphes  that  08  lb.  F.  units  of  heat  have  been  with- 
drawn from  it  in  order  to  dispose  of  the  latent  heat  of  the  vapour,  besides 
the  amount  necessary  to  cool  the  air  to  the  saturation  point ;  so  that  the 
deposit  of  an  ounce  of  water  upon  a  window  is  direct  evidence  of  the  passage 
of  08  lb.  F.  units  of  heat  at  least  through  the  window  glass.  This  is 
sufficient  to  reduce  the  temperature  of  375  cubic  feet  of  air  through  10°  F. 
so  that  the  deposit  of  moisture  may  be  used  as  a  tell-tale  for  any  large 
abstraction  of  heat  by  conduction. 

A  deposit  of  moisture  is  sometimes  formed  upon  a  wall  which  is  so  much 


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TEMPERATURE      IN       DEGREES       FAHRENHEIT 

Fig.  1. 


cooler  than  the  air  in  contact  with  it  that  the  air  is  reduced  in  temperature 
below  the  dew-point.  This  phenomenon  may  arise  from  two  separate 
causes  :  first,  the  replacement  of  the  air  by  warmer  and  moister  air  without 
any  change  of  temperature  occurring  in  the  wall,  as  when  in  a  sudden 
change  of  weather  from  frost  to  thaw  a  warm  moist  wind  replaces  the  cold 
air  in  contact  with  the  outsides  of  the  walls  of  buildings  rendered  cold  by 
the  previous  frost.  If  the  walls  are  porous  the  deposit  may  be  absorbed  and 
unperceived.  but  if  they  are  impervious  to  moisture,  being,  for  instance, 
cemented  or  painted,  the  beads  of  damp  are  very  striking,  and  in  this  case 
it  is  a  very  common  error  to  suppose  that  the  damp  comes  out  of  the  walls 


WABMING  AND   VENTILATION  47 

instead  of  being  deposited  upon  them  from  the  air.  The  second  cause 
referred  to  operates  when  the  walls  of  a  space  are  cooled,  the  internal 
air  remaining  unchanged.  Instances  of  this  can  be  tolerably  frequently 
observed  in  the  case  of  railway  carriage  windows,  which,  getting  colder  at 
night  or  on  passing  through  a  cold  district,  show  a  deposit  of  moisture  on 
the  inside.  It  is  interesting,  in  many  cases,  to  trace  the  cause  of  the 
deposit  of  moisture  which  may  be  observed,  and  to  decide,  for  instance, 
whether  the  dampness  observable  on  a  house-wall  is  due  to  a  deposit  from 
the  inside  air,  in  consequence  of  the  difference  of  temperature  between  the 
wall  and  the  air  inside,  or  to  the  moisture  rising  as  water  from  the  ground 
or  passing  through  the  wall  from  some  water  supply  outside  the  room. 

If  air  is  suddenly  cooled  dynamically,  the  moisture  is  not  in  the  first 
instance  deposited  upon  the  solid  substances  in  contact  with  the  air,  but  on 
the  small  solid  particles,  or  dust,  floating  in  the  air ;  these  particles  loaded 
with  their  deposit  of  moisture  form  a  mist  which  gradually  settles  upon  the 
ground  as  rain,  or  upon  the  sides  of  the  vessel  if  the  experiment  be  made 
upon  a  small  scale. 

Mr.  John  Aitken  has  found  that  solid  nuclei  furnished  by  dust  in  the  air 
are  essential  to  the  condensation  of  vapour  in  the  form  of  fog,  and  if  no  such 
nuclei  be  present  it  is  impossible  to  get  the  cloud  which  forms  so  easily  in 
moist  dusty  air  when  suddenly  rarefied.  Solid  surfaces  also  differ  very  con- 
siderably in  their  power  of  causing  a  deposition  of  moisture,  so  that  it  may  be 
difficult  to  test  very  accurately  whether  air  is  truly  saturated  or  not.  If  we 
regard  air  as  saturated  when  any  very  small  rarefaction  would  cause  a 
deposit  on  the  dust  nuclei,  then  certain  substances  condense  the  moisture 
out  of  air  which  is  not  thoroughly  saturated.  The  chemical  substances 
strong  sulphuric  acid  and  phosphoric  anhydride  remove  practically  every 
trace  of  moisture  from  the  air  in  contact  with  them  ;  calcium  chloride  and 
caustic  lime  also  absorb  moisture  freely  from  the  air,  and  may  be  used  to  dry 
it  if  particularly  dry  air  be  required ;  but  these  cases  must  be  regarded  as 
instances  of  chemical  actions  between  the  absorbing  substances  and  the 
moisture.  Other  substances  become  damp — possibly  on  account  of  fine  pores 
in  their  surfaces — in  air  which  is  not  nearly  saturated.  Wood,  whalebone, 
catgut,  are  all  in  their  way  hygroscopic,  and  so  is  hair  of  any  sort  when 
freed  from  grease.  In  consequence,  a  woollen  blanket  thoroughly  dried  will 
condense  several  pounds  of  water  in  its  pores  in  a  damp  cellar,  and  a 
sudden  change  in  the  weather  from  cold  to  warm  will  often  cause  woollen, 
linen,  and  cotton  materials,  especially  woollen  ones,  to  become  remarkably 
damp,  through  the  absorption  of  moisture  from  moist  but  not  saturated  air. 

A  large  quantity  of  moisture  is  introduced  into  the  air  of  rooms  by  the 
respiration  of  human  beings  and  by  the  burning  of  gas.  Unless  the  moisture 
is  removed  by  taking  away  the  heated  air,  it  becomes  deposited  upon  the 
walls  or  windows  as  the  room  cools  down  through  the  night.  This  leads  us 
to  remark  upon  methods  of  drying  a  room,  for  which  it  is  often  supposed  to 
be  sufficient  to  light  the  gas  in  it,  leaving  it  shut  up.  As  a  matter  of  fact, 
but  small  effect  can  be  produced  in  this  way  unless  ventilation  is  provided  to 
carry  away  the  heated  air  loaded  with  the  moisture,  for  unless  the  moisture 
is  actually  carried  out  of  the  room  in  some  such  way,  it  is  simply  evaporated 
by  the  heat,  condensed  again  upon  the  windows  and  walls,  and  re-evaporated 
the  next  day,  only  to  be  recondensed  in  the  following  night. 

Air  which  is  not  saturated  continually  takes  up  moisture  from  any  sm-face 
of  water  in  contact  with  it,  so  that  a  current  of  dry  air  passing  over  a  moist 
siu'face  is  a  very  effective  desiccator.  The  rate  at  which  the  evaporation 
takes  place  depends  upon  the  amount  of  moisture  already  in  the  air,  or 


48  HYGIENE 

rather  upon  the  ratio  of  the  amount  it  contains  to  the  amount  it  would 
-contain  if  saturated.  This  ratio  is  sometimes  called  the  fractional  humidity 
of  the  au",  and  is  generally  estimated  by  finding  the  actual  pressure  of  the 
water  vapour  in  the  air  and  comparing  it  with  the  saturation  pressure. 
From  the  curve  of  saturation  pressm'e  it  will  be  seen  that  a  given  fractional 
humidity  will  correspond  to  widely  different  quantities  of  moisture  in  the  air 
according  to  the  temperature.  The  thin-line  curve  of  fig.  1  (p.  46)  is  the  curve 
of  vapour  pressure  corresponding  to  the  fractional  humidity  of  the  air,  '5  ;  that 
is,  the  vertical  height  of  a  point  on  the  thin-hne  cm've  indicates  the  pressure 
of  vapour  in  the  air,  at  the  temperature  corresponding  to  the  horizontal 
distance  of  the  point  from  the  zero  line,  when  the  air  contains  half  the 
possible  amount  of  moisture  at  that  temperature.  Thus  air  may  be  rendered 
effectively  dry  without  altering  the  amount  of  moisture  in  a  cubic  foot  of  it 
by  simply  raising  its  temperature,  or  it  may  be  rendered  effectively  damp 
without  adding  any  water  to  it  by  simply  cooling  it. 

Hence  arise  the  differences  in  the  dampness  of  the  same  air  under  various 
conditions.  The  external  air  is  sometimes  saturated,  but  it  is  very  seldom 
in  England  that  the  humidity  falls  below  the  fractional  value  "5.  The 
average  humidity  in  England  may  be  taken  at  "75.  In  inland  tropical 
countries,  however,  it  is  frequently  much  drier  than  in  an  insular  climate  like 
that  of  the  British  Isles. 

A  wet  surface  exposed  to  a  current  of  dry  air  suffers  considerable  loss  of 
heat  in  consequence  of  the  evaporation  ;  thus  a  body  wrapped  in  wet  muslin 
Avill  have  its  temperature  reduced  from  60°  F.  to  40°  F.  if  it  be  exposed  to  a 
continuous  current  of  air,  itself  at  60°  F.,  when  the  fractional  humidity  of 
the  air  is  "24.  It  follows  that  damp  substances  exposed  to  a  ventilation  current 
of  very  dry  air  may  suffer  considerable  depression  of  temperature  and  cause 
chills  to  persons  exposed  to  it.  The  rapid  evaporation,  too,  from  the  skin 
produced  by  a  current  of  dry  air  is  sometimes  injurious,  so  that  ventilation  by 
artificially  warmed  air  is  unsatisfactory  unless  provision  is  also  made  for 
moistening  the  air  to  a  suitable  state  of  humidity.  The  humidity  should  not 
be  less  than  60  per  cent. 

The  moistening  can  only  be  secured  at  the  expense  of  the  heat  necessary 
to  produce  the  evaporation,  and  ought  to  be  carried  out  with  due  regard  for 
the  fact  that  if  the  room  into  which  the  warmed  and  moistened  air  is  carried 
is  surrounded  by  cold  walls  and  windows,  the  whole  arrangement  is  very 
similar  in  principle  to  a  still,  and  may  result  in  pernicious  deposits  of  water 
on  the  walls.  This  consideration  leads  us  to  point  out  one  of  the  advantages 
of  supplying  part,  at  any  rate,  of  the  artificial  heat  of  a  room  by  radiation 
which  primarily  warms  the  walls  and  tends  to  keep  them  hotter  than  the 
air,  and  so  prevent  any  deposit  of  moisture  upon  them. 


ON   DUST   AND    SMOKE 

13.  The  recent  investigations  of  several  scientific  men,  particularly  Mr. 
John  Aitken,^  F.E.S.,  and  Dr.  0.  J.  Lodge, ^  F.E.S.,  into  the  phenomena  ex- 
hibited by  the  dust  particles  carried  in  the  atmosphere,  have  brought  to  light 
and  explained  some  very  important  facts.  As  bacterial  germs  must  be  included 
in  the  category  of  solid  particles  conveyed  by  the  air,  these  recent  additions  to 
our  knowledge  are  of  great  interest  to  those  concerned  in  securing  the  purity 
of  the  air  we  breathe. 

'  On  the  Formation  of  small  clear  Spaces  in  Dusty  Air,  Trans.  B.S.E.  xxxii.  1884, 
p.  239.  -  Nature,  xxxi.  265. 


WABMING  AND   VENTILATION  49 

It  is  unnecessary  here  to  specify  exactly  the  nature  of  the  solid  particles 
that  may  be  found  in  air.  Fragments  of  all  kinds  of  substances,  animal,  vege- 
table, and  mineral,  may  be  exhibited.  The  nature  and  character  of  the  sohd 
impurities  carried  by  the  air  will  be  found  fully  discussed  in  the  article  Am. 

Ait  ken  has  recently  described  a  method  of  actually  counting  the  number 
of  dust  particles  in  a  cubic  centimetre  of  air.  He  iirst  dilutes  the  dusty  air 
with  air  altogether  free  from  particles,  and  when  a  suitable  stage  of  dilution 
has  been  reached  he  loads  the  remaining  particles,  contained  in  1  c.c,  with 
condensed  water  vapour,  and  thus  causes  their  rapid  precipitation  upon  a 
measured  surface,  and  then  counts  the  number  deposited  by  means  of  a 
magnifying  glass.  An  account  of  the  result  of  experiments  upon  a  series  of 
different  specimens  of  air  is  given  in  a  recent  volume  of  Nature  (xli.  p.  394), 
from  which  it  appears  that  the  number  of  particles  in  a  cubic  inch  of  '  fresh  ' 
air  may  vary  from  two  thousand  in  open  country  to  over  three  millions  in 
cities,  and  in  gas-heated  rooms  the  number  may  be  ten  times  as  great. 

The  method  of  determining  the  number  of  bacteria  in  air  is  dealt  with  in 
the  article  Air,  p.  28. 

The  suspended  dust  particles  are  constantly  falling  through  the  air  in 
consequence  of  the  action  of  gravity,  but  the  rate  of  fall  is  very  slow,  the 
motion  being  retarded  by  the  friction  they  meet  with.  It  is,  however,  quite 
appreciable  and  can  be  made  visible  by  suitable  apparatus  and  illumination. 
The  dust  is  maintained  in  suspension  in  the  air  by  the  currents  due  to  wind 
or  to  convection.  If  the  air  is  still  for  a  long  enough  period,  the  dust 
gradually  settles  upon  all  horizontal  surfaces,  and  the  air  becomes  tolerably 
free  from  it.  A  considerable  part  of  the  dust  of  air  may  indeed  be  removed 
by  simply  allowing  the  air  to  flow  slowly  over  a  horizontal  surface ;  if  the 
motion  is  rapid,  eddies  are  produced  by  the  friction  of  the  air  against  the 
sides  of  the  channel,  and  the  dust  is  carried  forward  and  is  not  allowed  to 
settle.  Moreover,  if  the  horizontal  surface  is  wet,  the  deposit  of  dust  does  not 
take  place  so  freely.  The  explanation  of  this  phenomenon  is  probably  to  be 
found  in  the  fact  that  the  water  is  constantly  evaporating.  The  molecules 
of  water  are  shot  out  from  the  surface,  and  so  cause  a  continuous  bombard- 
ment of  the  air  next  to  it ;  in  the  process  of  diffusion  the  molecules  are 
gradually  driven  further  away  from  the  surface.  These  molecules  are  inde- 
finitely smaller  than  the  dust  particles,  and  in  the  bombardment  the  dust 
particles  get  hammered  by  the  rising  water  molecules,  and  are  thus  driven 
away  from  the  surface  and  not  allowed  to  fall.  The  molecules  of  the  air  are 
themselves  in  rapid  motion,  so  that  the  dust  particles  receive  blows  from  every 
quarter ;  but  those  from  the  direction  of  the  evaporating  water  surface  pre- 
dominate, and  so  the  dust  is  kept  at  a  distance. 

In  a  precisely  similar  way  the  dust  will  be  kept  off  a  hot  surface  exposed 
to  dusty  air,  which  is  cooler  ;  only  in  this  case  the  molecules  by  which  the 
dust  particles  are  bombarded  will  all  be  of  the  same  kind.  Those,  however, 
which  touch  the  hot  surface  rebound  with  greater  velocity  than  they  strike, 
and  so  there  is  a  rain  of  molecules  leaving  the  wall  with  greater  average 
velocity  than  that  of  the  molecules  of  the  cooler  gas  near.  Again,  the  impacts 
are  heavier  and  the  dust  is  kept  off. 

Just  the  reverse  effect  is  produced  if  the  surface  is  cold  and  the  air 
warmer ;  then  the  predominant  effect  of  the  general  bombardment  drives  the 
particles  towards  the  wall  and  a  deposit  of  the  dust  takes  place. 

When  a  surface  is  both  moist  and  warm  the  repelling  action  is  still 
more  effective,  since  both  causes  combine  ;  and  to  this,  as  pointed  out  by 
Aitken,  is  probably  due  our  comparative  immunity  from  diseases  that  might  be 
contracted  from  the  passage  of  particle -laden  air  through  the  bronchial  tubes. 

VOL.   I.  E 


50 


HYGIENE 


The  most  conspicuous  illustration  of  the  phenomena  here  described  la 
furnished  by  the  deposit  of  soot  in  a  chimney,  the  sides  of  which  are  coolei- 
than  the  sooty  air  passing  up  the  chimney.  But  on  a  smaller  scale  the 
same  phenomenon  is  exhibited  wherever  warm  dusty  air  passes  over  a  cooler 
surface.  The  subjoined  sketch  (fig.  2)  shows  a  deposit  of  soot  or  dust  accumu- 
lated on  a  wall,  in  eighteen  months,  over  a  pair  of  vertical  hot-water  pipes  which 
rise  from  the  floor  of  the  room  and  pass  through  the  wall.  It  furnishes  a  very 
fair  measure  of  the  ca'oss-section  of  the  convection  current  of  hot  air  which  is 
the  result  of  the  heating  effect  of  the  pipe,  and  every  hot-water  pipe  near  a 
wall  tells  a  similar  tale.  A  similar  deposit  can  always  be  observed  round  the 
outlet  ventilators  for  warm  air,  where  the  dust  can  often  be  seen  sticking  to 
the  edges  of  the  opening  like  iron  filings  to  a  magnet. 

If  a  cold  surface  be  held  above  the  smoky  flame  of  a  lamp,  a  deposit  of 


Fig.  2. 


soot  is  at  once  produced,  but  if  the  surface  be  previously  heated  no  deposit 
takes  place. 

The  thickness  of  the  dust  deposit  will  depend  upon  the  difference  of 
temperature  between  the  air  and  the  surface,  and  if  there  are  inequalities  in  the 
temperature  difference  at  different  parts  of  the  surface  the  difference  in  the  dust 
deposit  will  show  it.  It  is  probably  on  this  account  that  the  pattern  of  the 
joists  above  a  ceiling  is  gradually  outlined  upon  the  ceilmg  by  a  smoke  or  dust 
deposit,  for  those  parts  of  the  ceiling  which  are  backed  by  joists  conduct  the 
heat  of  the  room  away  less  rapidly  than  the  intermediate  portions. 

These  dust  deposits,  which  are  incidental  to  water-pipe  and  hot-air 
systems  of  warming,  could  only  be  avoided  either  by  securing  that  the  walls 
are  made  warmer  than  the  air  by  means  of  radiation  from  open  fires  or  by 


WARMING  AND   VENTILATION  51 

introducing  the  air  free  from  dust.  It  is  not  possible  to  arrange  matters  so 
that  either  plan  shall  be  perfectly  feasible,  but  attention  to  either  or  both  points 
may  help  to  reduce  the  amount  of  the  deposit.  The  deposits  are,  liowever, 
not  without  their  advantages.  Considering  the  nature  of  the  dust  particles,  it 
is  sometimes  better  to  have  them  nailed  to  the  v/all  than  floating  about  in 
the  air,  however  unsightly  the  result  may  be,  for  when  once  fixed  to  the  wall 
they  are  not  easily  dislodged,  and  they  are  out  of  harm's  way.  Undoubtedly 
the  best  way  would  be  not  to  allow  such  particles  to  enter  the  room  with  the 
air  supplied  for  ventilation.  A  complete  air-filter  is  furnished  for  small 
quantities  by  a  plug  of  cotton-wool  moistened  with  glycerine  ;  but  this  plan 
is  not  applicable  where  very  large  quantities  of  air  are  required,  though  large 
cotton-wool  filters  are  sometimes  used.  In  the  mechanical  system  of  venti- 
lation adopted  in  the  chemical  laboratory  of  University  College,  Dundee, ^  the 
air  is  filtered  by  being  passed  through  jute  cloth  (light  Hessian)  stretched  on 
frames  17  feet  long  by  4  feet  wide.  In  this  case  the  presence  of  the  screen 
actually  increased  the  delivery  of  air  by  nearly  ten  per  cent.,  probably  by 
preventing  eddies.  The  screens  collected  2^  ^^s.  of  dirt  in  seven  weeks.  They 
last  about  a  year,  and  the  cost  is  about  Id.  per  yard. 

A  filter  of  any  sort  is  more  effective  if  it  is  colder  than  the  air  passing 
through  it ;  so  that  it  would  be  well  to  interpose  the  filter  in  such  a  position 
that  the  air  passes  through  it  after  being  warmed. 

A  large  chamber  into  which  the  warmed  air  is  delivered  before  being 
supplied  to  the  rooms  would  act  as  a  partial  filter,  from  the  fact  that  its  walls 
would  be  cooler  than  the  air.  Indeed,  if  the  air  is  passed  along  a  narrow 
annular  passage  between  two  coaxal  metal  tubes,  one  of  which  is  kept  hot 
and  the  other  cold,  the  air  may  be  entirely  purified  from  dust ;  ^  but  this  plan 
has  only  been  tested  on  the  scale  of  laboratory  experiment. 

In  order  to  take  out  some  of  the  dust  from  air  introduced  by  Tobin  tubes, 
a  small  chamber  is  sometimes  formed  at  the  bottom  of  the  tube,  and,  the  motioxi 
of  the  air  in  the  chamber  being  comparatively  slow,  part  of  the  dust  falls  upon 
the  bottom.  A  layer  of  water  has  been  recommended  in  addition  ;  but  this 
can  hardly  assist  the  deposit,  for  reasons  stated  above. 

It  is  perhaps  hardly  necessary  to  point  out  that  all  conduits  for  air, 
especially  for  artificially  warmed  air,  are  liable  to  accumulations  of  dust, 
although  the  air  which  passes  through  them  may  not  be  drawn  from  an 
especially  dusty  supply.  It  is  well  that  the  dust  should  be  thus  de- 
posited in  the  conduits  instead  of  passing  into  the  rooms  ;  but  at  the  same 
time  it  should  be  remembered  that  the  conduits  are  liable  to  become  fouled 
thereby,  and  to  prove  a  source  of  serious  danger  to  health  unless  they  are 
periodically  and  properly  cleaned,  and  provision  should  therefore  always  be 
made  for  getting  at  the  conduits  for  this  purpose.  Neglect  of  this  precaution 
sometimes  discredits  systems  for  supplying  warm  air  which  are  otherwise 
free  from  objection. 

Another  method  of  depositing  the  dust-particles  consists  in  electrifying 
them  by  discharging  electricity  into  the  dusty  air  from  a  sharp  point  con- 
nected with  an  electrical  machine.  The  particles  then  form  aggregations 
and  fall.  This  effect  of  electrifying  dusty  air  was  described  by  Aitken,  but 
more  fully  discussed  by  Lodge.  The  former  has  suggested  that  the  effect  of 
thundery  weather  in  turning  milk  sour,  and  the  like,  may  be  due  to  the  un- 
usual amount  of  deposit  of  bacteria  in  consequence  of  the  electrification ; 
while  the  latter  has  discussed  the  possible  application  of  the  method  on  a 
large  practical  scale  to  the  clearing  of  the  atmosphere  from  fog,  dust,  or  smoke. 

'  Carnelley's  Bejport  on  the  Heating  and  Ventilation  of  Sclwols,  p.  31. 
-  Aitken,  I.e. 

e2 


62 


HYGIENE 


ON  THE  MOTION  OF  AIK.  GENERAL  THEORY  OF  VENTILATION 


14.  The  process  of  continuous  ventilation  consists  in  the  admission  of  a 
quantity  of  air  to  a  room,  or  other  nearly  closed  space,  through  ducts  of 
various  forms  and  sizes,  comprised  in  the  general  term  '  inlet,'  and  the  simul- 
taneous removal  of  a  similar  quantity  of  air  by  other  ducts,  which  are 
generally  termed  '  outlets '  or '  exits.'  The  inlets  may  be,  in  any  particular  case, 
open  doors  or  windows,  special  tubes  provided  for  the  purpose,  or  merely  the 
crevices  which  always  exist,  as  the  doors  and  windows  cannot  be  made  to  fit 
perfectly  air-tight  in  their  frames.  To  give  a  complete  account  of  the  motion 
of  the  air  and  its  causes  is  impossible,  for  it  would  practically  be  the  solution 
of  a  most  complicated  problem  in  the  motion  of  gases,  as  a  brief  consideration 
of  a  simple  case  will  show.  Let  us  take  a  most  elementary  system,  which 
may  be  diagramatically  represented,  as  in  fig.  3.  The  space  to  be  ventilated 
is  represented  by  the  oblong  A  ;  it  is  provided  with  a  single  inlet  tube,  I,  and 
a  single  outlet,  0.  The  cause  of  the  motion  of  the  air  may  be  as  simple  as 
possible,  namely,  a  continuous  suction  at  0,  or  a  blowing  in  of  air  at  I  ;  and 
we  will  suppose  that  either  of  these  causes  corresponds  to  a  difference  of 
pressure,  between  the  external  aperture  of  I  and  the  external  aperture  of  0, 

which  is  constantly  maintained  by  some 
suction  or  blast  apparatus.  In  conse- 
quence of  this  difference  of  pressure,  air 
flows  along  the  inlet  to  A,  and  an  equal 
quantity  flows  out  of  A  by  the  outlet. 
Now,  for  a  given  difference  of  pressure, 
say  that  due  to  one-tenth  of  an  inch  of 
water,  the  amount  of  air  which  passes 
through  the  system  depends  upon  the 
area  of  section,  the  length  and  shape  of 
the  inlet,  and  the  nature  of  its  internal 
surface,  and  upon  the  corresponding  pro- 
perties of  the  outlet  tube ;  and  it  is,  more- 
over, affected  by  any  changes  of  tem- 
perature which  the  air  may  experience  in  passing  through  the  system.  The 
effects  of  these  modifying  circumstances  upon  the  flow  of  air,  which  may  be 
roughly  classified  as  being  effects  of  friction  and  of  temperature,  are  at  best 
only  very  inaccurately  known,  so  that  the  calculation  of  the  amount  of  flow 
for  any  special  case  is  only  an  approximation  ;  and  this  is  only  part  of  the 
problem.  A  complete  knowledge  of  the  ventilation  of  a  room  refers  not 
only  to  the  amount  of  air  supplied  and  simultaneously  withdrawn,  but  also  to 
the  path  which  the  incoming  air  takes  when  it  enters  the  room.  It  is  a  matter 
of  the  greatest  consequence  whether  the  fresh  air  supplied  proceeds  directly 
to  the  outlet  or  takes  a  more  devious  course.  We  ought,  therefore,  to  be 
able  in  some  way  to  specify  the  path  which  the  air  takes  after  it  enters  the  room 
until  it  is  finally  disposed  of  by  passing  out  at  the  exit  ;  or  we  might  aim 
at  stating  the  direction  in  which  the  air  is  moving  at  any  point  of  the  room. 
But  the  air  of  any  inhabited  room  is  generally,  from  causes  previously 
mentioned,  in  a  state  of  absolutely  indescribable  turmoil,  and  the  precise 
motion  defies  calculation.  Even  if  we  could  perform  the  necessary  calculation 
under  perfectly  permanent  conditions,  we  should  have  solved  an  ideal  problem 
and  not  a  real  one ;  for  the  conditions  may  be  said  to  be  practically  never 
permanent.  All  this  refers  to  the  simple  system  we  have  imagined,  and 
every  actual  system  is  more  or  less  compHcated  by  the  multiplicity  of  inlets 


Fio.  3. 


WABMING  AND   VENTILATION  53 

and  exits,  and  causes  of  flow.  We  cannot,  therefore,  undertake  the  complete 
numerical  solution  of  the  general  problems  of  ventilation  ;  but  we  shall  be 
able  to  show  that  certain  of  the  phenomena — for  instance,  the  motion  of  air 
through  tubes  and  apertures — do  lend  themselves  to  numerical  calculation, 
and  the  general  character  of  others  of  them,  as  the  distribution  of  air-currents 
in  a  room,  can  be  inferred  from  observation  of  special  cases  ;  so  that  really 
useful  information  may  be  obtained  from  a  consideration  of  the  effects  which 
are  likely  to  be  produced  under  given  conditions. 

We  shall  first  suppose  our  questions  limited  to  cases  of  what  is  termed 
*  steady  '  motion,  which  may  be  explained  as  follows  :  If  we  commence 
drawing  air  out  of  a  room  by  suction  at  one  end  of  the  ventilation  system, 
successive  portions  of  the  air  are  set  in  motion — some  of  the  air  of  the 
room  is  drawn  out,  the  pressure  in  the  room  is  reduced,  and  air  begins  to  be 
drawn  in  through  the  inlet.  If  the  suction  is  maintained  perfectly  constant 
for  some  time,  a  continuous  steady  flow  is  established  ;  that  is,  as  much  air 
comes  in  through  the  inlet  as  is  drawn  through  the  outlet ;  the  pressure  in 
the  interior  is  kept  diminished,  but  always  by  the  same  amount ;  and  the 
amount  of  air  in  the  room  does  not  alter  any  further  ;  and  the  same  is  true  of 
any  portion  of  the  space  in  the  inlet  or  outlet  tubes — it  always  contains  the 
same  amount  of  air,  neither  more  nor  less.  An  observer,  if  he  could  see  the 
motion  of  the  air  across  a  transverse  section  of  one  of  the  tubes,  would  see 
it  constantly  flowing  at  the  same  rate  ;  in  other  words,  the  velocity  of  the 
motion  of  a  portion  of  the  air  depends  upon  its  position  only,  and  does  not 
vary  from  time  to  time.  Since  the  quantity  of  air  in  the  space  which  is 
contained  between  any  two  parallel  sections  of  the  system  is  thus  invariable, 
it  follows  that  the  amount  which  crosses  the  one  section  to  enter  the  space 
is  the  same  as  the  amount  which  crosses  the  other  section  leaving  the  space. 
We  shall  refer  to  this  statement  as  the  Law  of  Continuity  of  Flow.  It  must 
be  remembered  that  it  is  the  quantity  of  air  which  flows  equally  across  every 
transverse  section  when  the  motion  is  steady,  and  that  the  quantity  flowing 
is  measured  by  the  toeight  of  air  which  passes  the  section  per  second  or  per 
minute,  as  the  case  may  be.  The  volume  which  is  occupied  by  a  quantity 
of  air  when  it  leaves  the  outlet  of  the  system  may  be  very  materially  different 
from  the  volume  which  an  equal  quantity  actually  occupies  before  entering 
the  inlet,  because  it  may  be  at  a  different  pressure  and  different  temperature. 
So  that,  strictly  speaking,  the  volume  of  air  which  crosses  any  section  of  a 
ventilation  system  is  not,  by  the  law  of  continuity  of  flow,  equal  to  the 
volume  which  crosses  any  other  parallel  section,  in  consequence  of  the 
compressibility  and  expansibility  of  the  air.  If  we  were  dealing  with  a  liquid 
instead  of  a  gas,  the  changes  of  volume  which  can  be  produced  by  changes 
of  pressure  and  temperature  within  the  range  of  ordinary  observation  in  a 
mass  of  liquid  like  water  are  so  extremely  slight,  that  there  would  be  no 
practical  error  in  regarding  the  volume  of  the  liquid  which  crosses  any  section 
as  being  the  same  throughout  the  system  ;  and,  indeed,  even  when  we  are 
dealing  with  air,  there  are  many  cases  in  which  the  variations  of  volume 
which  take  place  are  comparatively  slight,  for  the  differences  of  pressure  and 
temperature  which  produce  them  are  not  large ;  so  that  if  we  altogether 
disregard  the  alteration  of  volume,  and  consider  the  volume  of  air  which 
traverses  successive  sections  to  be  equal,  instead  of  the  weight  of  air,  we  shall 
probably  be  within  the  limit  of  error  which  is  imposed  by  inaccm-acies 
of  measurement.  As  the  quantity  of  air  which  crosses  any  section  of  a  steady 
ventilation- system  is  always  the  same  at  every  part  of  the  system,  it  is  a 
most  important  element  in  the  specification  of  the  action  of  the  system ;  we 
shall  frequently  refer  to  it  as  the  '  flow.'     Strictly  speaking,  it  ought  to  be 


54  HYGIENE 

measiired  by  the  weight  passing  any  section  ;  but  as  the  variations  in  density 
of  the  air  along  the  circulation  are  slight,  we  shall  generally  suppose  the 
flow  measured  by  the  volume  which  passes  any  section. 

To  take  a  specific  example.  Suppose  that  we  have  a  room  provided  with 
a  chimney  and  a  fireplace  in  Avhich  is  a  gas-jet  instead  of  afire  ;  and  suppose 
the  opening  of  the  fireplace  cloped  by  a  well-fitting  screen  with  a  single 
circular  opening  in  it  ;  and  suppose,  further,  that  we  measure,  by  means  of  an 
apparatus  to  be  described  later  (p.  105),  the  volume  of  air  which  flows  through 
this  opening, to  be  24  cubic  feet  per  minute,  the  temperature  being  62°  F.,  the 
barometric  pressure  being  at  the  same  time  30  inches  :  then,  referring  to 
equation  1,  p.  42,  we  find  that  the  u'cight  of  air  which  passes  per  minute 
through  this  aperture,  i.e.  the  weight  of  24  cubic  feet  at  G2°  F.  and  80  inches, 
is  12,840  grains  ;  and  by  the  principle  of  continuity  of  flow,  provided  the 
motion  be  steady,  the  same  w' eight  of  air  passes  out  of  the  top  of  the  chimney 
and  the  same  weight  enters  the  room  by  the  chinks  in  the  windows  and  door. 
But  the  volume  is  not  the  same,  for  the  entering  air  will  have  the  temperature 
of  the  outside — 42°  F.,  suppose  ;  so  that  the  volume  of  outside  air  which  enters 

will  be  diminished  to  — — — — ~'-  x  24,  i.e.  about  23   cubic   feet :  and  if  we 
459  +  02 

suppose  the  temperature  of  the  air  issuing  from  the  chimney  to  be  150°  F., 

the  12,840  grains  when  they  pass  out  of  the  chimney  will  occupy  a  volume 

— '—— — ^  X  24  cubic  feet,  i.e.  about  28  cubic  feet.  We  have  left  pressure 
451>  +  62  ^       • 

differences  out  of  account,  though  there  is  a  difterence  of  pressure  on  the 

whole  of  about  ^Vptl^  of  an  inch  in  the  case  mentioned.     As  this  is  less  than 

r,  ,}(^  ^th  part  of  the  whole  pressure  of  the  atmosphere,  the  variations  on  this 

account  of  the  volume  of  the  air  delivered  at  different  parts  of  its  route  are 

so  small  that  they  may  safely  be  disregarded. 

We  have  laid  down  the  condition  that  the  motion  is  steady  ;  if  experiment 
were  made  upon  the  actual  instance  given  above,  it  would  in  all  probability 
be  found  that  the  wind  blowing  across  the  top  of  the  chimney,  or  directly 
upon  the  windows,  seriously  interfered  with  the  steadiness  of  the  motion. 
In  fact,  in  some  actual  measurements,  the  flow  through  the  same  aperture  in 
four  successive  minutes  was  24*5,  24'1,  22*9,  25*1  cubic  feet  respectively.  In 
such  a  case  we  have  to  infer  what  the  flow  would  be  under  steady  condi- 
tions, by  taking  the  mean  of  a  number  of  consecutive  observations,  or 
prolonging  one  observation  over  a  long  period.  The  effect  of  unsteadiness 
due  to  the  wind  is  less,  the  greater  the  flow  produced  by  permanent  artificial 
causes  ;  or,  in  other  Avords,  the  observations  of  artificially  maintained  ventila- 
tion currents  are  more  definite  and  trustworthy  the  greater  the  velocity. 
This  should  be  borne  m  mind  in  considering  observations  of  the  flow  in 
ventilation  channels.  When  the  artificial  current  is  weak  and  the  wind  at 
all  strong  or  gusty,  no  observations  of  any  value  can  be  obtained. 

The  law  of  continuity  of  flow  may  be  regarded  as  the  first  fundamental 
principle  in  the  theory  of  ventilation,  and  needs  only  to  be  stated  for  its 
importance  to  be  allowed.  It  accomits  for  many  of  the  most  easily  observed 
phenomena  of  ventilation  ;  the  disagreeable  draught  which  a  fire  produces 
in  a  room  is  one  of  the  most  familiar  instances  of  its  application.  At  the 
same  time  it  ia  one  of  the  principles  most  frequently  disregarded,  for,  of  the 
number  of  houses  built,  only  a  very  small  fraction  exhibit  any  evidence  of 
proAision  for  air  to  enter  in  a  satisfactory  manner  to  replace  that  which  must 
necessarily  be  removed  by  the  chimneys  and  other  outlets. 

For  the  purpose  of  numerical  calculation  the  law  of  continuity  can  only 
be  applied  to  those  sections  of  a  system  where  the  motion  is  steady.     The 


WABMING  AND    VENTILATION  55 

steady  state  is  gemerally  well  established  in  the  ducts  by  which  the  air  enters 
or  leaves  the  ventilated  space  ;  but  in  the  space  itself  local  causes  interfere 
with  the  steadiness  of  the  motion  of  the  air,  and  may  cause  the  velocity  of 
flow  at  any  point  to  change  from  time  to  time  in  a  manner  which  cannot  be 
accurately  calculated  numerically.  We  must  therefore  analyse  the  general 
problem  into  two  parts  and  treat  them  separately.  The  first  part  deals  with 
the  steady  flow  through  the  ducts,  and  this  we  will  denominate  the  '  general 
circulation  '  in  the  system  ;  the  laws  which  regulate  it  will  be  stated  and  ex- 
emplified. The  second  part  deals,  on  the  other  hand,  with  the  motion  of  the 
air  in  the  ventilated  space,  which  is  generally  irregular ;  about  this  part  we 
can  only  give  the  results  of  observations  upon  special  examples,  which  will, 
however,  enable  us  to  form  a  rough  estimate  of  the  approximate  distribution 
of  flow  in  a  room  under  specified  conditions,  and  from  which  some  principles 
of  general  application  can  be  derived.  The  irregularity  of  the  motion  of  the 
air  in  the  room  does  not,  however,  interfere  with  the  general  application  of 
the  law  of  continuity,  which  enables  us  to  say  that  the  total  quantity  of  air 
entering  by  the  inlets  is  equal  to  that  which  passes  in  the  same  time  through 
the  outlets. 

General  Circulation 

15.  In  order  to  form  a  definite  conception  of  the  laws  which  govern  the  flow 
of  air  through  ducts,  we  shall  first  consider  their  application  to  a  very  simple 
case,  and  then  show  how  the  theory  may  be  extended  to  more  complicated 
cases.  This  method  of  treatment  has  been  suggested  by  a  very  instructive 
work  by  M.  Murgue  on  '  The  Theories  and  Practice  of  Centrifugal  Ventilating 
Machines,'  translated  by  A.  L.  Steavenson.  The  simple  but  most  typical 
case  of  flow  of  air,  which  forms  the  starting-point  of  the  theory,  is  that  in 
which  air  is  driven  through  an  aperture  in  a  thin  plate,  when  a  steady  dif- 
ference of  pressure  is  maintained  betAveen  the  two  sides  of  the  plate.  We 
shall  not  now  stop  to  consider  the  way  in  which  the  pressure-difference  can 
be  maintained  ;  to  that  part  of  the  subject  we  shall  devote  a  special  section 
subsequently.  We  may  picture  to  ourselves  two  very  large  spaces — two  rooms, 
for  example,  A  and  B,  fig.  4. — with 
a  small  aperture  a  in  a  thin  sheet 
of  metal  separating  them.  The  pres- 
sure in  A  is  to  be  maintained  at  the 
steady  value,  say  P  lbs.  per  square 
foot,  and  the  pressure  in  B  at  j;  lbs. 
per  square  foot.   We  must,  however.  Fig.  4. 

make  clear  what  is  here  meant  by 

the  pressure  of  the  air.  The  motion  of  air  through  the  orifice  will  affect  the 
pressure  of  the  air  in  its  neighbourhood  ;  if  we  carry  an  instrument  for  measur- 
ing pressure  (for  instance,  an  aneroid  barometer  made  sufficiently  delicate  to 
indicate  the  very  minute  changes  of  pressure  that  occur  in  such  cases)  from 
any  remote  corner  of  A  towards  the  orifice,  the  pressure  will  remain,  practically 
speaking,  constant,  until  a  position  quite  near  to  the  orifice  is  reached ;  then 
the  pressure  will  show  signs  of  diminution,  and  it  will  continue  to  diminish 
until  the  orifice  is  passed,  and  even  after  that  for  a  very  short  distance,  until 
we  arrive  at  the  position  of  most  rapid  motion  ;  after  that  the  pressure  will 
gradually  increase  to  a  uniform  value  in  the  space  B  at  any  considerable 
distance  from  the  orifice.  We  may  call  those  parts  where  the  air  has  any 
considerable  motion  the  *  rapids  '  ;  and  when  we  speak  of  the  pressure  of  the  air 
in  the  space  A  or  B,  it  must  be  understood  that  the  measure  is  not  taken 
within  the  rapids.     Some  idea  of  the  extent  of  the  rapids  may  be  obtained 


.-\\ 

A 

>:^:| 

A-~ 

B 

•56  HYGIENE 

from  a  consideration  of  the  special  cases  of  the  flow  of  air  in  the  neighbour- 
hood of  inlets  and  outlets  which  will  be  described  hereafter  (§  30). 

In  consequence  of  the  steady  difference  of  pressure,  equivalent  to  (P — ^j) 
lbs.  per  square  foot,  a  steady  motion  is  mamtained  through  the  orifice.  At 
the  orifice  itself,  the  air  is  converging  from  all  directions,  so  that  the  '  vein ' 
of  flowing  air  contracts  after  passing  the  orifice  until  the  position  of  maximum 
velocity  is  reached.  The  vein  afterwards  spreads  out  again  as  the  velocity 
diminishes,  and  has  therefore  a  section  of  minimum  area  at  the  part  at  which 
its  velocity  is  greatest ;  and  there,  moreover,  the  direction  of  the  motion  of 
each  portion  of  the  air,  as  it  passes,  is  perpendicular  to  the  plane  of  the  orifice. 
The  general  character  of  the  vein  of  air  may  be  to  a  certain  extent  inferred 
from  the  analogous  case  of  the  motion  of  water  through  an  opening  in  a 
plane  plate,  or  from  the  flow  of  a  river  through  the  arch  of  a  bridge ;  the 
eddies  that  are  formed  in  the  debatable  region  between  flowing  stream 
and  dead  water  have  their  counterpart  in  the  eddies  which  are  set  up  in  the 
air  beyond  the  orifice. 

There  are  also  other  phenomena  which  the  motion  of  the  air  exhibits. 
When  air  expands  on  change  of  pressure  the  temperature  is  reduced,  so  the 
air  in  the  rapids  will  be  cooled.  The  differences  of  pressure  which  occur  in 
ordinary  cases  of  ventilation  are,  however,  extremely  small,  and  some  of  the 
heat  is  returned  to  the  air  by  the  friction  at  the  orifice  and  in  the  space  B. 
In  those  cases  in  which  a  greater  difference  of  pressure  is  required,  as  in 
mines,  the  flow  takes  place,  not  through  an  orifice  in  a  thin  plate,  but  through 
long  shafts,  and  the  temperature  is  really  determined  by  the  shaft  in  which 
it  flows  ;  hence  we  may  disregard  the  changes  of  temperature  that  occur  in 
consequence  of  the  expansion. 

16.  Let  us  now  consider  more  closely,  but  still  in  quite  general  terms,  the 
conditions  that  are  necessary  in  order  to  maintain  the  steady  flow  through 
the  orifice.  The  air  will  not  go  through  it  of  its  own  accord  ;  it  requires  some 
agent  to  drive  it — to  maintain,  in  fact,  the  difference  of  pressure.  There  are 
several  practical  ways  of  doing  it  :  blowing  with  suitably  arranged  bellows 
into  the  space  A  would  be  one  way ;  using  an  engine  to  drive  a  fan  blast 
another ;  maintaining  a  fire  to  heat  air  in  a  chimney  in  communication  with 
B,  a  third  ;  but  all  these  involve  the  use  of  working  agents — the  worker  of  the 
bellows,  the  engine,  or  the  fire  as  the  case  may  be.  To  drive  a  pound  of  air 
through  the  orifice  every  second  requires  the  expenditure  during  each  second 
of  a  certain  amount  of  work,  which  may  be  measured  in  foot-pounds,  or  the 
number  of  pounds  weight  which  the  same  amount  of  work  would  hft  through 
a  foot.  We  shall  give  a  special  name  to  the  amount  of  work,  measured  in 
foot-pounds,  which  must  be  spent  in  driving  one  pound  of  air  through  the 
orifice  :  it  will  be  called  the  Head,  corresponding  to  the  flow.  We  shall  subse- 
quently calculate  the  head  for  a  number  of  special  cases  of  circulation,  but 
for  the  present  we  shall  content  ourselves  with  specifying  that  when  we  say 
that  the  head  for  a  flow  through  an  orifice  is  one-tenth  of  a  foot-pound  per 
pound,  we  mean  simply  that  every  pound  of  air  which  passes  through  the 
orifice  uses  up  in  doing  so  one-tenth  of  a  foot-pound  of  work.  We  shall 
generally  denote  the  head  in  foot-pounds  by  the  symbol  lb-' 

'  In  order  to  give  a  more  definite  idea  of  the  meaning  of  the  term  '  head,'  we  may 
Tefer  to  the  analogous  case  of  the  tlow  of  water  through  an  orifice  when  the  water  is  at 
different  levels  on  the  two  sides.  In  that  case  the  '  head  '  (or  work  done  in  foot-i30unds 
jier  iDound  of  water  flowing  through)  is  equal  to  the  difference  of  level,  h,  of  the  water  on 
the  two  sides  of  the  orifice.  Similarly,  in  the  case  of  air  the  head  represents  the  height  to 
•which  air  would  have  to  be  piled  on  the  one  side  of  the  orifice  in  order  that  the  difference 
of  weight  of  the  columns  on  the  two  sides  might  produce  the  same  result  as  the  head, 


WARMING   AND    VENTILATION  57 

We  can  consider  how  the  work  is  spent  as  the  air  passes  through  the  orifice, 
including  in  the  time  of  the  passage  of  a  portion  of  air  the  whole  time  from 
the  instant  at  which  the  portion  becomes  involved  in  the  rapids  to  the  instant 
when  it  reaches  the  most  contracted  part  of  the  vein.  Its  velocity  becomes 
gradually  accelerated  from  its  initial  value,  which  is  practically  zero,  to  the 
maximum  value,  which  we  may  take  to  be  v.  It  is  a  well-known  dynamical 
principle  that  to  generate  a  velocity  of  -y-feet  per  second  in  a  mass  of  1  lb. 

requires    —   or  — - — -   foot-pounds  of  work  ;  hence  each  pound  of  air 
2(/  2x32-2 

requires  for  the  production  of  the  velocity    — — — ^    foot-pounds  of  work, 

which  is  subsequently  frittered  away  to  heat  by  the  friction  in  the  second 
space  B  and  lost  for  all  practical  purposes.  If  this  were  the  only  way  of 
spending  the  work,  we  should  have  the  simple  relation  between  the  head  *It), 
and  the  maximum  velocity  v. 

But  the  calculation,  of  which  the  equation  just  written  expresses  the  result, 
proceeded  on  the  assumption  that  the  head  was  devoted  entirely  to  the  increase 
of  velocity  of  the  air.  This  would  leave  out  of  account  the  work  which  is  lost  in 
friction  at  the  orifice  ;  so  that  the  equation  as  it  stands  is  not  directly  applicable. 
It  is  fortunately  unnecessary  for  us  to  attempt  to  correct  it  by  estimatmg 
separately  the  effect  upon  the  flow  which  is  produced  by  the  convergence  of 
the  vein,  the  friction  and  the  eddies  which  it  causes,  and  the  other  phenomena 
which  occur  in  the  rapids.  Experiments  have  shown  that  the  resultant 
effect  can  be  represented  with  sufficient  accuracy  for  practical  purposes  by 
supposing  them  to  produce  a  constriction  of  the  area,  over  which  the  maxi- 
mum velocity  v  may  be  supposed  to  be  uniform.  Thus,  what  really  takes 
place  when  a  difference  of  pressure  is  maintained  on  the  two  sides  of  an 
orifice  is,  that  air  flow^s  through  the  orifice  a  in  convergent  directions  and 
meets  with  frictional  resistance ;  the  flow  in  the  general  circulation  can, 
Jiowever,  be  calculated  on  the  supposition  that  it  is  equivalent  to  a  flow  which 
passes  perpendicularly  through  a  narrower  orifice  over  which  the  velocity  is 
uniform,  and  equal  to  the  maximum  velocity  which  the  head  would  produce 
if  there  were  no  friction.  The  velocity  can  thus  be  calculated  by  the  formula 
given  above.  The  experiments  further  show  that  the  area  of  the  contracted 
orifice  always  bears  the  same  ratio  to  the  actual  orifice  for  different  heads,  so 
that  the  contracted  orifice  can  always  be  calculated  from  the  actual  area,  a, 
■of  the  given  orifice  by  multiplying  by  a  fraction,  Tc,  which  is  called  the  co- 
efficient of  contraction.  Thus  the  area  of  the  contracted  orifice  is  ha.  We 
may  now  state  the  resultant  effect  of  the  action  of  a  head,  lb ;  it  produces  a 
flow  which  is  represented  by  a  uniform  velocity,  v,  of  the  air  perpendicularly 
across  an  area  Tea,  where  a  is  the  area  of  the  orifice,  and  h  the  coefficient  of 
contraction,  the  velocity  at  the  contracted  area  being  related  to  the  head  lb. 

by  the  equation  lb  =  ^ — ; 


2  X  32-2* 


supposing  that  the  air  did  not  vary  in  density  and  could  have  a  free  surface  like  water. 
It  follows  from  this  that  the  difference  of  pressure  on  the  two  sides  is  that  due  to  a  column  of 
air  of  uniform  density  whose  height  is  numerically  equal  to  the  head,  or  is  equal  to  that  of 

a  column  of  water  whose  height  is  h  feet,  whereZi  =  i?^  ,  A  being  the  density  of  the  air 

A 

aear  the  orifice,  and  A'  the  density  of  water.  The  ratio  —  is  the  specific  gravity  of  air 
referred  to  water,  and  may  be  taken  as  being  approximately  equal  to  1/800. 


58  HYGIENE 

We  can  further  calculate  what  volume  of  air  passes,  for  it  is  equivalent  to 
the  volume  delivered  at  velocity  v  through  the  contracted  area  ka.  If  areas 
are  measured  in  square  feet,  and  velocities  in  feet  per  second,  the  flow  will 
evidently  be  hav  cubic  feet  per  second.  Let  us  call  the  volume  dehvered  in 
cubic  feet  per  second  V  ;  then 

and  we  get  for  the  relation  between  the  volume  V  delivered  at  the  contracted 
area  and  the  head  If)  which  causes  the  flow, 

113  = \ _. 

Pa^x  2x32-2 

The  volume  delivered  across  any  other  section  may  be  calculated  in 
accordance  with  the  law  of  continuity  of  flow  ;  but  if  we  neglect  the  differ- 
ences of  density  of  the  air  at  different  sections,  as  we  generally  may  do  with- 
out appreciable  error,  we  may  assume  that  the  vohmie  delivered  is  the  same 
across  any  section ;  though,  as  already  pointed  out,  it  is  really  the  weight  of 
air  which  passes  any  section  which  is  the  same  throughout. 

The  flow  through  the  orifice  may  as  a  rule  be  easily  found  experimentally 
by  means  of  an  air-meter  (see  p.  105),  which  when  properly  used  gives  the 
mean  velocity  perpendicu.lar  to  the  area.  The  corrected  reading  of  this 
instrument  gives  the  value  Y  ja  for  any  opening  through  wloich  the  air  flows, 
and,  a  being  measurable,  the  value  of  V  becomes  a  quantity  which  is  capable 
of  fairly  accurate  experimental  determination.  It  is,  in  fact,  the  measurement 
in  relation  to  ventilation  which  is  most  easily  carried  out  in  practice,  and 
hence  the  equation  connecting  1b  and  V  is  of  very  great  importance.  We 
may  regard  it  as  the  statement  of  the  second  fundamental  principle  of  venti- 
lation, the  law  of  relation  between  head  and  flow  for  an  orifice  in  a  thin  plate. 

The  constant  h  is  not  very  accurately  known,  but  it  does  not  differ  much 
from  "65,  whatever  be  the  shape  of  the  orifice.^  In  what  follows,  except  where 
otherwise  specified,  we  shall  take  its  value  at  '65,  and  the  law  of  relation, 
between  head  and  flow  through  an  orifice  in  a  thin  plate  becomes — 

1h= I =  _!_. 

2  X  32-2  X  (•65)2a2     ^Ta^ 

We  may  transpose  the  equation  to  the  following  : 

1b_  1 

V^     27a2 

and  we  notice  that  the  right-hand  side  of  the  equation  is  a  numerical  constant 
for  an  orifice  of  given  area  ;  so  that  we  may  enunciate  the  second  fundamental 
law  as  follows  : — The  ratio  of  the  head  to  the  square  of  the  flow  is  a  constant 
which  is  inversely  proportional  to  the  square  of  the  area  of  the  orifice  ;  this 
constant  we  may  if  we  please  call  the  resistance  of  the  orifice,  and  ex- 
press the  statement  thus  : — The  head  is  equal  to  the  product  of  the  resist- 
ance of  the  orifice  and  the  square  of  the  flow,  or  the  flow  is  equal  to  the 
square  root  of  the  head  divided  by  the  resistance  of  the  orifice,  and  we  may 
write  the  equation  finally  : 

when  E  is  the  resistance  and  V  the  flow.  If  the  head  is  expressed  in  foot- 
pounds per  pound  of  air  and  the  flow  in  cubic  feet  per  second,  E  will  be  equal 

to  — —    when  a  is  the  area  of  the  orifice  in  square  feet.     Those  who  are 

27a^ 
familiar  with  ordinary  dynamics  may  prefer  the  resistance  of  the   orifice 
expressed  in  more  general  terms,  so  that  the  condition  of  referring  the  head 
'  See  Peclet,  TraiU  de  la  Chaleur,  i.  154. 


WARMING  AND    VENTILATION  59 

and  flow  to  particular  units  need  not  be  imposed.  We  therefore  write  for  R 
its  equivalent  value,  Iji^Agk-a^),  where  g  is  the  gravitational  acceleration  of  any- 
falling  body,  a  the  area  of  the  orifice,  and  k  the  coefficient  of  contraction. 

In  concluding  this  section  we  may  give  a  definition  of  the  resistance  of 
an  orifice  in  the  technical  sense  in  which  we  shall  use  the  term.  It  is  the 
factor  by  which  the  square  of  the  numerical  value  of  the  flow  through  the 
orifice  must  be  multiplied  in  order  to  give  the  value  of  the  head  which  pro- 
duces the  flow. 

One  of  the  direct  results  which  follow  from  this  equation  is,  that  we  are 
enabled  to  calculate  the  head  between  the  two  sides  of  a  thin  plate  by 
observing  the  flow  through  a  measured  orifice.  For  instance,  in  some 
observations  upon  the  draught  of  air  the  average  velocity  of  the  air  passing 
through  a  circular  opening  three  inches  in  diameter  in  a  sheet  of  millboard 
was  found  by  means  of  an  air-meter  to  be  8  feet  per  second.  The  area  of 
the  orifice  was  -049  square  foot,  and  the  flow  consequently  "392  cubic  foot 
Ijer  second.  The  resistance  of  the  orifice  may  be  calculated  out  to  be  15"6  ; 
whence  it  follows  that  the  head  required  to  maintain  the  flow  through  the 
orifice  is  15-6  x  (-392)2,  j  g_  2-4  foot-pounds  per  pound  of  air  traversing  the 
orifice.  Prom  the  considerations  given  in  the  footnote  on  p.  54  we  see  that 
this  head  would  imply  a  diflerence  of  pressure  on  the  two  sides  of  the  orifice 
which  corresponds  to  a  difference  of  level  of  "036  of  an  inch  of  water. 

Extension  of  the  theory  to  ducts  of  any  length  and  form 

17.  We  have  hitherto  only  considered  the  motion  of  air  through  an  aperture 
in  a  thin  plate  ;  but  the  theory  may  be  very  easily  extended  to  any  duct  what- 
ever. For  if  we  consider  the  flow  of  air  along  a  duct,  we  have  losses  of  head 
due  to  friction  against  the  sides  of  the  channel,  to  sudden  bends,  or  to  changes 
of  diameter,  besides  the  loss  due  to  friction  on  entering  the  duct,  and  possibly 
to  the  contraction  of  the  vein  where  the  air  emerges.  All  these  account  for,  or 
use  up,  part  of  the  head,  and  the  remainder  alone  is  available  for  producing  the 
velocity  which  constitutes  the  flow.  But,  as  will  be  seen  shortly,  everyone  of 
these  items  of  expenditure  of  head  is  proportional  to  the  square  of  the  flow, 

so  that  instead  of  equating  the  head  to  a  single  term  -—^V^,  we  must  equate 

A  la 

it  to  the  sum  of  a  number  of  terms  representing  severally  the  expenditure 

of  head  on  friction,   bends,  changes  of  diameter,   and  finally  velocity  of 

emergence.     Each  one  of  the  terms  will,  however,  contain  V^  as  a  factor  ;  so 

that  the  equation  takes  the  form — 

1b=(a  +  Z)  +  c-ffZ+     ....  )\\         .         .        .    (2) 

where  the  factors  a,  b,  c,  .  .  .  refer  to  the  losses  of  head  due  to  the  several 
causes  specified.  The  separate  terms  may  be  calculated  separately  if  we  have 
complete  information  as  to  the  shape,  size,  and  nature  of  the  surface  of  the 
duct ;  but  even  if  we  cannot  calculate  them,  we  can  see  that  the  factors 
a,  b,  c,  .  .  .  might  at  any  rate  all  be  added  together  and  the  sum  of  them 
called  E,  and  we  get  the  equation  in  the  form 

1I3=RV^ (2*) 

which  is  identical  in  form  with  that  for  the  motion  through  the  aperture  in 
a  thin  plate;  only  in  this  case  we  cannot  calculate  the  value  of  R,  or  at  least 
not  so  easily  as  for  the  use  of  a  thin  plate  aperture.  But  we  can  still  speak 
of  R  as  the  resistance  of  the  duct,  and,  as  in  the  case  of  a  thin  plate  aperture, 
it  is  independent  of  the  flow  ;  and,  moreover,  we  can  see  that  different  ducts 
may  have  the  same  resistance,  and  may  therefore  be  regarded  as  equivalent. 


60  HYGIENE 

Of  two  equivalent  ducts,  one  may  be  an  orifice  in  a  thin  plate  the  area  of  "wbich 
can  be  calculated,  as  we  have  seen,  fi'om  the  resistance.  Hence  we  may  repre- 
sent the  resistance  of  a  duct  as  the  resistance  of  the  orifice  in  a  thin  plate  to 
which  it  is  equivalent,  and  if  we  can  measure  the  resistance  of  a  duct  we  can 
calculate  the  area  of  the  '  equivalent  orifice  '  in  a  thin  plate,  and  in  this  way 
specify  the  properties  of  the  duct  in  regard  to  the  transmission  of  air.  If,  for 
instance,  from  any  cause  the  resistance  of  a  duct  be  increased,  as  by  increasing 
its  length,  or  by  a  deposit  of  soot  on  its  surface,  we  may  at  once  represent  the 
increase  by  a  corresponding  diminution  in  the  area  of  its  equivalent  orifice. 

The  definition  of  the  resistance  of  a  duct  is  identical  with  that  for  a  simple 
aperture,  namely,  the  ratio  of  the  head  to  the  square  of  the  flow.  If  these 
two  quantities  can  be  measured,  the  resistance  can  be  at  once  calculated  and 
the  area  of  the  equivalent  orifice  determined.  We  shall  shortly  describe 
methods  of  measuring  the  resistance  without  directly  determining  the  head, 
and  shall  thus  be  enabled  to  find  from  such  measurements  the  orifice  to  which, 
say,  a  chimney  is  equivalent,  and  to  compare  different  chimneys  in  respect  of 
then-  resistance  or  equivalent  orifices,  and  this  without  even  so  much  as 
knowing  what  the  area,  shape,  or  state  of  the  chimney  may  be. 

The  idea  of  expressing  the  '  conducting  power,'  if  we  may  so  term  it, 
of  a  duct  by  means  of  the  equivalent  area  in  a  thin  plate  is,  so  far  as  we 
know,  due  to  M.  Murgue.  It  evidently  enables  us  to  render  remarkably 
precise  a  large  mass  of  information  that  was  before  hazy  and  vague.  We 
may  sum  up  by  restating  our  second  general  laio  of  ventilation  in  terms 
appHcable  to  any  duct  whatever,  as  follows.  The  ratio  of  the  head  to  the 
square  of  the  flow  is  a  constant  called  the  resistance  of  the  duct,  which 
depends  on  the  size,  shape,  and  surface  of  the  duct,  but  is  independent  of 
the  flow,  and  for  the  purposes  of  transmission  of  air  the  duct  is  equivalent  to 
the  orifice  in  a  thin  plate  which  has  the  same  resistance  as  the  duct,  the 
area  of  the  equivalent  orifice  a  being  connected  with  the  resistance  K  by  the 
1 


relation  K 


27^2 


Third  and  Fourth  Latvs  of  Ventilation.  Application  of  the  first  tioo  Funda- 
mental Laws  of  Ventilation  to  the  Indirect  Determination  of  the  Besist- 
ance  of  a  Duct  and  of  the  Head  producing  the  Floio  in  a  given  Duct. 

18.  We  have  already  seen  that  one  of  the  characteristic  properties  of  a 
duct  of  any  shape  and  length  is  its  resistance  to  the  flow  of  air  through  it.  It 
is  of  great  importance  to  the  accurate  study  of  any  actual  system  of  ventilation 
that  the  resistances  or  equivalent  orifices  of  its  air-ducts  should  be  known. 
The  resistance  of  any  duct  may  be  calculated  approximately,  in  a  manner 
that  win  subsequently  be  described,  from  the  measured  dimensions  of  the 
duct  and  from  its  shape,  assuming  certain  experimental  results  as  to  the 
coefficient  of  air-friction,  and  the  effect  of  bends  and  other  singularities 
upon  the  flow  of  air.  The  calculation  is,  however,  elaborate  and  tedious,  and 
in  the  end  not  very  satisfactory,  except,  as  already  indicated,  for  the  case  of 
an  aperture  in  a  thui  plate,  when  the  calculation  is  sufficiently  simple  and 
accurate,  the  resistance  of  a  thin  plate  aperture  of  area,  a,  being,  as  already 

explained,  ^^. 

Now  it  is  possible  when  a  flow  of  air  passes  through  a  combination  of 
ducts  to  infer,  ixom.  observations  of  the  flow  merely,  the  relations  between 
the  resistances  of  the  several  ducts ;  and  thus,  if  one  of  these  ducts  be  itself 


WABMING  AND    VENTILATION  61 

an  aperture  in  a  thin  plate,  and  its  resistance  therefore  known,  the  resistance 
of  the  others  can  be  calculated,  without  any  direct  measurement  of  their 
dimensions.  This  method  has  been  employed  by  M.  Murgue  in  the  work 
already  referred  to  for  the  particular  case  of  the  ventilation  of  mines  by 
fans ;  but  it  seems  capable  of  very  considerable  extension  and  very  wide 
application. 

19.  We  shall  now  give  three  examples  of  it.  I.  As  a  j&rst  instance  we  will 
take  M.  Murgue's  case  in  which  we  have  a  space,  S,  communicating  with  the 
external  air  by  two  ducts,  i  and  o  (fig.  5),  one  of  which,  i,  is  a  thin  plate 
aperture,  and  the  other  duct,  o,  of  unknown 
dimensions  and  resistance.  We  shall  further 
suppose  that  the  area  of  i  can  be  altered,  as, 
for  example,  by  sliding  shutters,  indicated  in 
the  figure,  and  can  at  any  time  be  measured, 
and  thus  its  resistance  calculated.  To  fix 
ideas,  S  may  be  regarded  as  a  fairly  ample 
fireplace,  o  the  chimney,  and  i  an  opening  in 
a  screen  in  front  of  the  fireplace ;  the  windows 
of  the  room  may  be  supposed  open.  We  shall 
also  assume  that  the  flow  through  the  two 
ducts  is  maintained  by  a  constant  ^  head,  H). 
Now,  referring  to  the  phenomena  described  in 
the  case  of  the  motion  of  air  through  an 
aperture  in  a  thin  plate  (p.  55),  it  will  be  Fig.  5. 

noticed  that  air  began  to  take  part  in  the  flow 

through  the  aperture  as  soon  as  it  got  in  the  rapids,  and  we  must  have  a 
similar  understanding  with  regard  to  the  flow  through  the  duct  0  ;  that  is  to 
say,  if  we  are  to  be  able  to  apply  the  second  law  of  ventilation  to  the  motion 
through  0,  the  space  S  must  be  so  large  that  the  air  is  practically  at  rest,  or 
only  moving  very  slowly  in  the  part  between  the  rapids  of  influx  at  i  and 
the  rapids  of  efflux  at  0.  If  this  condition  be  not  satisfied  the  resistance  of 
the  ducts  will  not  be  independent  of  the  flow.  From  the  want  of  experimental 
data,  we  are  unable  to  give  the  precise  relation  of  the  dimensions  required 
for  any  given  flow.  Assuming,  however,  that  S  is  sufficiently  large,  it  is 
evident  that  the  second  law  of  ventilation  may  be  appHed  to  the  two  ducts  i 
and  0  separately. 

Thus  let  O  be  the  resistance  of  0,  1b  1  the  head  between  S  and  the  top  of 
0,  and  V  the  consequent  flow. 

Then  1bi=f^V2         .         .         .        p.  59,  by  eq.  2*. 

Similarly,  let  A  be  the  resistance  of  i,  and  1b2  the  head  for  flow  through  it. 
Then  11)2  =  A  V^ "" 

for  by  the  first  law  of  ventilation  the  flow  through  both  ducts  is  the  same. 
Moreover,  from  the  fact  that  the  head  for  a  duct  is  the  work  done  upon 
one  pound  of  air  flowing  through  it,  it  follows  that  the  sum  of  the  heads  for 
the  two  ducts  is  the  whole  head  for  the  system,  or 

1bi+lb2  =  lb 

From  which  ^  we  get         ^ 

lb  =  (A  +  n)  V« (3) 

*  This  would  be  the  case  with  a  ventilating-fan,  and  approximately  so  with  a  fire- 
draught,  but  not  strictly  so  in  that  and  some  other  cases.  If,  however,  the  alteration  of 
head  can  be  calculated,  this  does  not  affect  the  principle  of  the  method  under  consideration. 

-  Or,  in  words,  the  sum  of  the  resistances  of  two  separate  ducts  is  the  resistance  of  the 
whole,  regarded  as  a  single  duct. 


62  HYGIENE 

But  further,  suppose  that  the  area  of  I  is  altered  hy  sliding  the  shutters 
so  that  its  resistance  becomes  A'  and  the  flow  through  the  system  V'. 

Then,  since  lb  remains  the  same,  we  get  another  equation  similar  to  (3), 

t)  =  (A'  +  fi)  V'2 ; 
whence  (A  +  fi)  V^  =  (A' +  O)  V'^ 

But  V  and  V  can  be  measured  by  the  air-meter  described  below,  and 
hence  may  be  regarded  as  known  quantities,  and  so  are  the  resistances  A  and 
A' ;  and  consequently  we  can  calculate  the  value  of  O,  for  it  is 

A'  y'''  -  A  Y^ 
equal  to   — ■  y2  _  y/2 — 

It  is  also  evident  that  when  fi  has  been  thus  determined,  the  head  lb  and 
the  partial  heads  Ibi  and  flDa  can  likewise  be  calculated,  and  thus  all  the 
elements  of  the  system  of  ventilation  deduced,  from  observations  of  the 
measurement  of  flow  and  the  area  of  the  adjustable  aperture  in  the  thin 
plate  denoted  by  i  in  the  figure.  The  resistance  of  the  duct  o  being  thus 
determined,  the  area  of  its  equivalent  orifice  is  easily  deduced  by  the  equa- 
tion of  p.  58. 

As  an  example  of  the  calculation  of  the  resistance  and  equivalent  orifice 
of  a  chimney  by  this  method,  we  may  quote  from  some  observations  made 
upon  a  chimney  in  the  Cavendish  Laboratory,  Cambridge.  The  chimney  has  no 
firegrate,  but  gas  was  burned  in  it  to  produce  a  head  ;  the  front  was  covered 
by  a  wooden  screen,  and  the  openings  denoted  by  i  were  represented  by  circular 
areas  cut  in  millboard.  Two  of  the  observations  were  as  follows  : 
Area  of  i  -098  sq.  ft.  Flow  -842  cub.  ft.  per  sec. 
„     i'  -294  sq.  ft.     Flow  1-G2  cub.  ft.  per  sec. 

From  which  we  obtain 

resistance  of  chimney  =  '88 
equivalent  orifice  =  "205  sq.  ft. 

The  actual  area  of  section  of  the  chimney  at  the  lowest  part  is  "875 
sq.  ft.,  so  that  the  friction  of  air  against  the  sides,  and  bends  in  the  chimney 
reduce  the  effective  area  to  about  one  quarter  of  the  measured  cross-section. 
From  the  same  results  we  get — 

The  total  head  •lb=6'6  foot-pounds  per  pound  of  air,  which  is  approxi- 
mately equivalent  to  a  pressure  of 
I  one-tenth  of  an  inch  of  water  ;  and 

^  the  partial  heads  1b  i  and  1b2  can  be 

similarly  determined. 

II.  The  next  example  of  the 
application  of  this  method  is  but  a 
slight  modification  of  the  former, 
and  is  represented  by  fig.  6.  In 
this  we  have  three  ducts,  represented 
by  0,  i,  and  a  respectively,  of  which 

.>       -s      ^ 1     the  adjustable  opening  i  separates 

Y  the  space  previously  denoted  by  S 

into  two  parts,  Si  and  S2,  and  the 
duct  a  may  be  taken  to  represent 
the  chinks  of  windows  and  doors 
in  the  absence  of  a  special  inlet.  If  now  each  of  these  spaces  be  sufficiently 
large  for  the  interference  of  the  respective  '  rapids  '  to  be  disregarded,  we 
may  again  treat  each  duct  separately,  and,  regarding  the  total  head  fl?  as 


s,     \    s 


Fig.  6. 


WABMING  AND    VENTILATION 


63 


D 


constant,  and  made  up  of  the  three  partial  heads  1b i,  lb;.,  lbs,  the  resistance 
of  the  ducts  being  i2,  I,  and  A,  we  have — 

1bi=iiV,2 

1b2=rV,^ 

1b3=AV,'^ 

V,  being  the  measured  flow  expressed  in  cubic  feet  per  second.  From  these 
three  equations  we  get 

1bi+1b2  +  1b3=1b=(^  +  I  +  A)V,'^        .         .         .     (4) 

or  the  equivalent  resistance  of  the  whole  system  is  again  the  sum  of  the 
resistance  of  its  three  parts.  By  altering  the  adjustable  opening  to  i'  we  get 
another  equation-^ 

1b=(^+I'  +  A)  V2^ (5) 

where  Vo  is  the  flow  observed  in  the  second  case. 

These  two  equations  enable  us  to  find,  not^  and  A  separately,  but  il  +  A. 
N«w  if  A  represents  the  resistance  of  the  chinks 
&c.  by  which  the  air  finds  its  way  to  the  chimney 
when  the  window  and  doors  are  shut,  A  may 
be  abolished  altogether  by  setting  the  window 
wide  open,  and  il  determined  as  in  the  first  ex- 
ample; then,  having  found  ii  and  i2+  A,  we  can 
determine  A,  the  resistance  of  the  chinks. 

III.  The  third  example  of  the  indirect  method 
of  determining  the  resistance  of  ducts  is  repre- 
sented in  fig.  7,  and  illustrates  the  case  of  what 
may  be  called  parallel  orifices.  In  this  case  three 
ducts,  0,  i,  a,  all  open  directly  into  the  space  S. 

We  have  drawn  the  duct  a  horizontal  in 
order  to  indicate  that  no  head  is  produced  by 
it,  as  might  be  the  case  if  it  were  vertical  and 
there  were  any  temperature  differences.  We  may 
accordingly  assume  that  the  head  is  the  same  for  the  two  ducts  i  and  a,  and, 
supposing  that  the  whole  head  1b  is  made  up  of  the  partial  heads  Ibi  and 
Ibs)  and  that  O,  A,  and  I  represent  resistances,  we  get  the  following  equations  : 

lbi=iiVi2 

1b2=I^i'=A^;2' 

where  Vi  and  V2  are  the  parts  of  the  whole  flow  Vi  passing  through  i  and  a 
respectively. 

But  by  our  first  general  law 

hence  \/l^4  7!  +  ix  }  =  ^^ 


s 


Pig    7, 


or 


1b2  = 


T  )>  Vi^  . 


Whence  we  ffet 


(«) 


(7) 


6-1  HYGIENE 

Equation  (7)  represents  the  relation  between  H),  fl,  I,  A,  and  V,  of  which  I 
and  V,  are  known.  If  the  area  of  i  be  altered,  a  fresh  equation  is  obtained, 
and  so  by  determining  the  flow  corresponding  to  three  separate  values  of  the 
area  i,  we  obtain  three  equations  from  which  we  can  determine  the  resistance 
of  the  ducts  A  and  12  and  the  total  and  partial  heads. 

This  example  illustrates  a  practical  method  of  determining  the  resistance 
of  the  chinks  in  doors  and  windows  by  providing  an  additional  adjustable 
and  measurable  aperture.  It  is,  however,  liable  to  serious  disturbance  from 
the  effects  of  wind. 

It  should  be  noticed  that  equation  (6)  is  an  example  of  a  general  law, 
easily  proved  on  the  same  line  of  reasoning,  viz. : — 

LA  W  3.  That  when  two  or  more  ducts  are  parallel  and  themselves  produce 
no  head,  their  effect  is  the  same  as  that  of  a  single  duct  whose  equiva- 
lent orifice  is  equal  to  the  sum  of  the  equivalent  orifices  of  the  separate 
ducts. 

We  have  already  seen  in  the  two  previous  examples  instances  of  the  ap- 
plication of  the  law  holding  in  the  case  of  the  ducts  through  which  air  flows 
successively,  or  ducts  '  in  series,'  as  they  may  be  called  for  the  sake  of  clear- 
ness.   We  repeat  it  here  as — 

LA  W  4.  The  resistance  of  any  number  of  ducts  in  series  is  the  sum  of  the 
resistances  of  the  separate  ducts,  provision  being  taken  for  the  non-interference 
of  their  rapids. 

In  a  subsequent  chapter  we  shall  endeavour  to  show  how  these  four  laws 
can  be  applied  to  the  explanation  of  some  important  problems  in  ven- 
tilation. 

Calculation  of  the  Resistance  of  an  Air -duct  from  its  Shape  and 

Dimensions 

20.  In  the  previous  section  we  have  shown  how  the  resistance  of  an  air- 
duct  can  be  determined  indirectly  by  a  method  which  practically  compares  the 
resistance  of  the  duct  with  that  of  a  measured  aperture  in  a  thin  plate ; 
we  now  proceed  to  consider  the  calculation  of  the  resistance,  by  means  of 
tabulated  data,  from  the  specification  of  the  shape  and  dimensions  of  the  duct, 
and  the  nature  of  the  materials  of  which  it  is  constructed.  As  the  basis  of 
calculation  we  take  the  results  of  experiments  upon  the  flow  of  air  through 
ducts  of  measured  size  and  shape,  principally  derived  from  Peclet's  '  Traite  de 
la  Chaleur,'  vol.  i. 

The  practical  difference  between  the  two  methods  amounts  to  this — that 
in  order  to  employ  the  former  the  duct  must  have  been  actually  constructed, 
whereas  for  the  latter  we  require  only  the  architect's  specification  of  the 
work  for  it ;  and  therefore  it  follows  that,  while  the  former  method  is  the 
one  most  easily  applicable,  and  probably  most  accurate,  for  the  purpose  of 
criticising  a  system  of  ventilation  already  in  existence,  and  in  correcting  the 
data  employed  in  and  checking  the  results  predicted  by  the  latter  method, 
this  latter  must  be  solely  relied  upon  in  designing  a  system  of  ventilation 
to  satisfy  certain  specified  requirements.  We  have  already  seen  that  we  can 
express  the  motive  force  which  propels  or  draws  the  air  along  a  duct  by 
specifying  the  head,  that  is,  the  amount  of  work  which  is  required  to  be 
done  upon  each  pound  of  air  during  its  passage  ;  and  we  have  also  remarked 
that,  in  the  case  of  any  duct,  part  only  of  this  work  is  spent  in  producing  the 
velocity  with  which  the  air  traverses  the  duct,  and  the  rest  is  wasted  in 
friction  in  various  ways,  and  we  have  represented  the  relation  between  the 
head  lb,  and  the  flow  V,  by  an  equation  (p.  59)  1[3=(a.-t-&-f  c-f-fZ  +  ...)  V,- 
when  the  factors  a,  b,  c,  ...  refer  to  the  waste  of  head  by  friction  in  the 


WARMING  AND   VENTILATION 


65 


various  ways.  We  now  wish  to  justify  this  equation  and  to  express  the 
various  losses  of  head  in  terms  of  the  dimensions  of  the  duct.^ 

In  order  to  fix  our  ideas  as  to  the  elements  which  have  to  be  considered  in 
the  problem,  let  us  represent  by  A  B  C  D  E  F  (fig.  8)  the  duct  employed 
to  convey  air  from  the  space  R  to  the  space  0  ;  and  let  us  suppose  that,  under 
the  action  of  a  head  lb,  V  cubic  feet  of  air  enter  the  duct  at  A  every  second. 
If  we  can  neglect  changes  in  the  density  of  the  air,  the  flow  as  measured  in 
cubic  feet  across  every  transverse  section  will  be  the  same. 

Let  us  examine  a  little  more  closely  the  motion  of  the  air  in  the  various 
sections  of  the  duct,  so  that  we  may  appreciate  the  various  causes  of  waste  of 
energy.  As  the  air  prepares  to  leave  the  space  E,  rapids  are  formed  about 
the  opening  A,  and  the  lines  of  motion  oi  the  air  converge  and  cause  a  con- 
traction of  the  effective  orifice.  A  short  distance  withm  the  tube  A  B,  the 
jet  of  air  reaches  its  minimum  section,  and  the  motion  is  parallel  to  the  sides 
of  the  tube.  From  this  section  the  jet  gradually  expands  until  it  fills  the  whole 
tube  at  the  section  x. 

From  the  orifice  A  to  the  section  x  the  jet  of  moving  air  occupies  only  a 
portion  of  the  cross-section  of  the  duct ;  the  rest  is  occupied  by  air  which  is 


Fig.  8. 


maintained  in  a  continual  state  of  whirling  or  eddying  motion  by  the  friction 
with  the  undefined  boundary  of  the  moving  jet.  The  friction  of  the  eddies  pro- 
duces heat,  and  here  we  have,  therefore,  the  first  portion  of  energy  wasted,  viz. 
that  which  is  converted  into  heat  in  the  rapids  and  eddies  about  the  orifice  A. 

From  X  to  near  B,  the  motion  of  the  air  is  parallel  to  the  sides  of  the 
duct,  and  here  there  is  loss,  due  to  the  friction  of  the  air  against  the  sides. 
Work  is  again  spent  in  the  friction  and  converted  into  heat.  For  the  sake 
of  clearness  we  distinguish  this  loss  as  loss  by  air-friction,  although  it  may 
not  be  really  different  in  its  nature  from  the  loss  in  the  rapids  ;  it  depends, 
however,  on  the  nature  of  the  surface  and  on  the  length  and  internal  girth 
of  a  straight  duct.  It  is,  moreover,  distinct,  in  the  sense  that  it  is  quite  un- 
avoidable, for  we  cannot  have  a  duct  without  sides,  whereas  we  can  avoid 
abrupt  changes  of  shape  and  abrupt  bends. 

The  air  is  now  supposed  to  have  reached  the  rectangular  bend  B  where 
it  has  to  change  the  direction  of  its  motion  ;  but  its  inertia  causes  it  to 
impinge  upon  the  further  side  of  the  portion  B  C,  and  another  contraction 
of  the  jet  takes  place,  leaving  a  portion  of  the  area  occupied  by  eddies,  and 
likewise  the  part  in  the  angle  at  B.     After  the  contraction,  which  takes  place 

'  For  full  details  of  this  part  of  the  subject  see  Peclet,  Traite  de  la  Chaleiir,  vol.  i. 
1878  ;  or  Morin,  Etudes  sur  la  Ventilation,  vol.  i.  chap.  iv.  1863. 

VOL.   I.  F 


eS  HYGIENE 

just  after  passing  the  angle,  the  jet  again  spreads  out  and  fills  the  tube 
at  some  section  y.  Again  we  have  a  loss  of  energy  in  the  friction  of  the 
eddies,  which  we  may  call  the  loss  of  energy  due  to  a  rectangular  bend  in 
the  duct.  From  the  section  y  the  motion  is  again  parallel  to  the  sides  of 
the  duct,  and  the  air  passes  on,  losing  energy  only  by  friction,  imtil  the  curved 
bend  C  is  reached,  on  the  further  side  of  which  we  have  another  contraction 
of  the  jet  and  fui'ther  loss  in  eddies.  We  need  not  continue  the  minute 
description  of  the  motion ;  there  will  be  losses  of  energy  in  eddies  at  D 
when  the  area  of  the  duct  is  suddenly  increased  at  E,  when  the  area  is 
suddenly  diminished,  and  eddies  are  also  produced  at  the  orifice  of  emergence 
F,  between  the  issuing  jet  and  the  surrounding  air.  Finally,  the  air  issues 
from  the  orifice  at  F  with  a  velocity  which  can  be  calculated  from  the  flow 
and  the  area.  The  work  which  is  required  for  all  these  operations  is 
derived  from  the  agent  (engine  or  furnace  chimney)  which  maintains  the 
head.  Hence  we  may  suppose  work  done  in  maintaining  the  head  as  dis- 
tributed into  the  following  items  : — 

a.  Work  spent  in  friction  of  eddies  at  orifice  of  entry. 

b.  ,,  ,,  ,,  a  rectangular  bend. 

c.  „  ,,  „  a  curved  bend. 

d.  „  „  „  a  sudden  enlargement. 

e.  „  „  „  a  sudden  contraction. 

f.  „  ,,  ,,  at  orifice  of  exit. 

g.  „  ,,  against  the  sides  of  the  duct  when  the  section 

is  uniform. 
h.  „  generation  of   the  velocity  of  the  air  at    the  orifice 

of  exit. 

If  we  can  express  the  work  spent  in  each  one  of  these  items  corresponding 
to  the  flow  of  1  lb.  of  air  thiough  the  duct,  we  may  take  the  head  as  numeri- 
cally equal  to  the  sum  of  the  separate  items. 

It  must  of  course  be  understood  that  the  duct  we  have  described,  although 
it  contains  a  number  of  points  of  interest,  is  still,  comparatively  speaking, 
regular  in  form,  and  is  only  an  approximate  representation  of  a  real  duct. 

Let  us  now  consider  the  magnitudes  of  the  difi'erent  items — 
[a)    Loss  of  head  at  orifice  of  entry 

This,  for  unit  weight  of  air  passing,  can  be  expressed  by  slightly  altering 

1        /I  \  V^ 

a  formula^  of  M.  Peclet  (op.  cit.  vol.  i.  p.  154),  as  - — -— -    ( — ^  —  1  )  — 
^  -^  ^         2  X  32*2  \m^         J   a^' 

where  V  is  the  flow  in  cubic  feet  per  second,^  a  the  area  of  the  section,  and 

m  is  the  coefficient  of  contraction  of  the  orifice  wbich  has  the  value  '728 

when  the  duct  is  as  drawn  in  the  figure.     The  coefficient  depends  on  the  form 

of  the  orifice.     By  making  the  entrance  into  the  duct  trumpet- shaped,  the 

loss  under  this  head  can  be  entirely  avoided.'* 

'  We  have  expressed  the  losses  throughout  in  terms  of  the  square  of  the  flow. 
M.  Peclet  expresses  them  in  terms  of  a  quantity jj,  which  is  related  to  the air-velocityt;, by 
the  equation  v  =  'J'lg-p. 

-  To  avoid  complexity,  we  shall  assume  the  air  to  remain  of  the  same  density  through- 
out the  duct.  If  this  assumption  be  not  admissible,  the  losses  under  the  different  heads 
should  be  expressed  in  terms  of  the  locight  W  of  air  flowing  per  second  ;  the  formula  in  this 

case  becomes    ^—  ~  1^    — >  ^  being  the  density  of  the  air  at  the  section  referred 

2  X  32-2  \m-       /   -A- 

to.    Corresponding  changes  would  be  required  in  each  successive  item. 

3  For  the  effect  of  different-shaped  mouthpieces,  see  Peclet,  vol.  i.  chap.  iv. 


WABMING  AND    VENTILATION 


07 


(b),  (c)  Losses  at  bends 

For  bends  made  by  the  junction  of  two  straight  tubes,  Peclet  {op.  cit.  vol.  i. 

1  V^ 

p.  209)  gives  the  formula   - — — — -    sin^i.— -    when  i  is   the  angle   between 

2Xo2'2  a^ 

The  formula  ^ 


2x32-2 
the  two  consecutive  portions  of  the  duct  as  indicated  in  fig.  9. 
is  applicable  to  angles  between  20°  and  90°.    For  still  larger  angles,  the  proper 
value  of  the  loss  of  head  is  uncertain  ;  for  smaller  angles,  the  bend  may  bo 


a>-:  > 


Fig.  9. 


V  ii* 


Fig.  10. 


Fig.  11. 


Fig.  12. 


For  such  Peclet  saya 
X  -.-  is  satisfactorily 


more  accurately  treated  as  if  it  were  a  curved  bend. 

i°  1 

that  the  formula  for  the  loss  of  head  — ---  x  - — — - 

180°      2  X  32-2 

confirmed  by  experiment,  i°  being  the  angle  through  which  the  duct  is  bent 

from  the  continuation  of  its  original  direction,  as  shown  in  fig.  10.     Comparing 

the  formulae  for  angular  and  curved  bends,  it  appears  that  for  the  same  flow 

the  loss  of  head  for  a  curved  bend  of  180°,  as  in  fig.  11,  is  only  one  half  of 

that  for  the  same  flow  with  two  rectangular  bends,  as  in  fig.  12,  producing 

the  same  effect  in  respect  of  change  of  direction. 

{d)  Loss  of  head  at  a  sudden  enlargement 
Thisis  not  easily  expressed.  Peclet  (op.  ci^.  vol.  i.  chap,  vii.)  gives  the  formula 

1)4  \  Y2 

for  cylindrical  ducts  (— B  +  1  -  .^--^ )   _ —        — -„,  where  Di  is  the  diameter 

of  the  larger  part,  D  that  of  the  smaller  part,  and  B  is  a  quantity  which 
likewise  depends  on  the  ratio  of  the  diameters  and  has  a  maximum  value  '47 
when  the  ratio  of  the  diameters  is  '6  :  1. 

(e)  Loss  of  head  at  a  sudden  contraction 

This  is  the  same  as  the  loss  which  takes  place  at  the  entrance  of  a  duct 
provided  with  a  cylindrical  mouthpiece  of  greater  area  than  that  of  the  duct. 

<?>2        ;2x32-2xa2' 

'  See  Parkes's  Hygiene,  p.  191,  according  to  which  the  velocity  in  a  bent  pipe  is  to 

that  in  a  straight  pipe  as  1  :  1  +  sin^9  between  0°  and  90°,  or 1 —  :  1  between  0°  and 

180°. 

f2 


The  loss  may  be  represented  by 


being   the    area 


68 


HYGIENE 


of  the  narrowed  portion,  where  </>  is  a  contraction-coefficient  varying  between 
•83  and  unity  as  the  ratio  of  the  diameters  changes  fi'om  -1  to  1. 

(/)  Loss  of  head  at  the  orifice  of  discharge 
When  the  duct  terminates  by  a  straight  portion  as  m  the  figure  (fig.  8), 
there  is  practically  no  appreciable  contraction  of  the  orifice,  but  the  flow  for  a 
given  head  is  affected  by  the  mouthpiece  with  which  the  tube  terminates.  The 
effect  of  different  orifices  is  discussed  by  Peclet,  op.  cit.  vol.  i.  p.  184.  (i.)  When 
the  duct  is  terminated  by  a  cylindrical  tube,  of  diameter  narrower  than  that 

of  the  duct,  we  have  a  loss  of  head  ( -=  —1  1 

of  the  narrow  tube,  and  (p  is  a  coefficient  of  contraction  similar  to  that  given 
above  under  [e).  (ii.)  When  the  duct  is  terminated  by  a  converging  conical 
orifice,  the  loss  of  head  is  represented  by  the  same  formula,  a  being  the  area 
of  the  narrow  end  of  the  cone.     The  following  table  gives  the  value  of 

<p  and   -s  —  1  for  different  angles  of  the  cone. 


V2  , 

where 

'2x32-2«2 


the 


area 


Table 

IV. 

Angles 

Values  of 

Angles 

Values  of                        | 

1     , 

-' 

1       ^ 

<!> 

-  -1 

-#> 

r~ 

0° 

1-00 

0-00 

100 

0-80 

0-56 

10 

0-97 

0-06 

120 

0-75 

0-78 

20 

0-93 

0-16 

140 

0-73 

0-88 

30 

0-89 

0-26 

150 

0  71 

0-98 

40 

0-86 

0-35 

160 

0-69 

1-10 

60 

0-83 

0-45 

170 

0-67 

1-23 

80 

0-82 

0-49 

180 

0-65 

1-366 

(iii.)  When  the  duct  ends  in  a  divergent  cone  or  a  trumpet -shaped  orifice, 
the  flow  is  somewhat  improved,  provided  the  angle  of  the  cone  is  less  than 
50°.  The  maximum  effect  is  produced  when  the  angle  of  the  cone  is  7°. 
Details  as  to  the  numerical  values  are  given  in  Peclet,  op.  cit.  vol.  i.  p.  187. 

(iv.)  When  the  orifice  is  covered  by  a  grating,  we  have  a  mouthpiece  whose 
area  is  equal  to  the  sum  of  the  areas  of  the  spaces  of  the  grating,  and 
whose  coefficient  of  contraction  lies  between  the  coefficient  for  an  aperture 
in  a  thin  plate  -65  and  the  coefficient  for  a  cylindrical  mouthpiece  '83. 
The  effective  area  of  a  grating  can  be  considerably  increased  by  bevelling  the 
gratmg  on  the  side  from  which  the  air  flows. 

{cj)  Loss  of  head  due  to  friction  against  the  sides  of  a  shaft 
of  uniform  section 

If  we  suppose  a  straight  shaft  made  up  of  successive  short  tubes  or  rings, 
Ei,Pki2,E3,  E4,  fig.  13,  each  one  foot  in  length,  the  effect  of  the  frictional 


7 


Fio.  1£ 


resistance  offered  by  the  sides  of  the  shaft  to  the  flow  of  air  along  it  may  be 
represented  as  a  force  acting  upon  the  air  contained  in  each  ring  and  propor- 
tional in  magnitude  to  the  area  of  contact,  i.e.  the  length  of  the  ring  e,  multiplied 


WABMING  AND   VENTILATION  69 

by  the  perimeter  abed,  or  girth,  of  the  internal  section  of  the  shaft.  For 
a  shaft  of  circular  section,  radius  r,  the  perimeter  is  27rr  ;  for  a  rectangular 
tube,  2  (a  +  b).  The  force  also  depends  upon  the  velocity  of  motion  of  the 
air  in  a  manner  which  is  at  present  somewhat  obscure.  If  the  flow  is  very 
slow,  the  resistance  is  approximately  proportional  to  the  velocity ;  but,  if  the 
velocity  exceeds  six  inches  per  second,  the  relation  between  the  force  of  re- 
sistance and  the  velocity  is  more  nearly  represented  by  the  assumption  that 
the  frictional  resistance  varies  as  the  square  of  the  velocity.  The  resistance 
may  also  be  assumed  to  be  proportional  to  the  density  of  the  moving  air. 
The  force  in  lbs.  weight  acting  upon  a  ring  at  which  the  velocity  of  motion 
is  V  will  therefore  be 

& 
where  S  is  the  perimeter  of  the  section  of  the  shaft, 

A  the  density  of  the  moving  air, 
g  the  acceleration  of  gravity,  32"2  feet  per  second, 
jS  a  constant  which  must  be  experimentally  determined ; 

it  depends  upon  the  nature  of  the  surface  of  the  shaft,  being  very  largely 
increased  if  the  surface  is  roughened. 

The  work  done  by  this  force  in  one  second  is  Fv  foot-pounds,  and  this 
corresponds  to  the  passage  of  W  lbs.  of  air  ;  hence  the  work  lost  in  friction 
on  the  passage  of  one  pound  of  air  through  the  ring,  or  loss  of  head  for  each 
ring,  is 

Fv  _l3Sv^A    V  _  PSv'^Av  _/3S^^ 
W  ^       *W         gvAA  gk    ' 

where  A  is  the  area  of  section  of  the  tube. 

The  differences  of  pressure  which  are  used  to  produce  ventilation  currents 
are  so  small  that  we  may  without  sensible  error  disregard  the  differences 
■of  density  caused  by  the  alteration  of  pressure.  If  we  do  so,  the  velocity 
in  a  uniform  shaft  will  be  the  same  throughout,  and  hence  the  work 
lost  by  friction  will  be  the  same  for  each  ring ;  hence  if  L  be  the  length 
of  the  pipe  (i.e.  the  number  of  1-foot  rings)  the  total  loss  of  head  due  to 
friction  is 

__  — I   i^  '^    foot-pounds  per  pound  of  air  delivered. 

A      ^" 
The  relation  •—  is  sometimes   called  the  '  hydraulic  mean  radius '  of  the 

D 

shaft.    Denoting  this  by  m,  we  have 

/3Lv2 

y  =J 

mg 

The  value  of  the  coefficient  /3  is  of  vital  importance  to  any  problem  of 
designing  ventilation  shafts ;  but  it  has  not  yet  been  fully  investigated. 
Some  experiments  byM.  Arson  (see  'Encycl.  Brit.' vol.  xii.  p.  491)  tend  to  show 
that  for  cast-iron  pipes  /B  is  not  constant,  but  depends  on  the  velocity  of  the 
air,  and  the  diameter  of  the  pipe  [the  constant  4  there  employed  is  related 
to  the  /3  used  by  Morin  by  the  equation  2/3  =  C] ,  and  for  diameters  between 
1-64  feet  and  -164  feet  varies  between  -00242  and  -00606  for  a  velocity  of 
100  feet  per  second.  M.  Poncelet,^  discussing  the  researches  of  MM. 
-Girard  and  D'Aubisson,  assigns  the  value  -0032  to  /3.  But  the  value  of  /3 
is  liable  to  be  very  greatly  increased  by  roughness  of  the  surface  of  the  shaft. 
Thus  in  brick  shafts  the  projections  of  mortar  and  deposits  of  soot  very 

•  Morin,  Etudes  sur  la  Ventilation,  i.  181,  1863. 


70  HYGIENE 

largely  increase  tlie  coefficient,  and  in  "wooden  shafts  the  roughness  of  the- 
wood  and  deposits  of  dust  are  similarly  effective.  General  Morin  concludes, 
therefore,  that  until  experiments  furnish  more  accurate  values  for  /?,  it  must 
not  be  assumed  to  be  less  than  "01  for  a  chimney-shaft.  Peclet,  on  the  other 
hand,  assigns  the  value  "003  for  the   coefficient  of  friction.      The  loss  of 

head  by  fi-iction  is  therefore  represented  by  the  formula or' — -— — 

m  g         m  K^  g, 

where  V  is  the  flow  in  feet  per  second  and  A  the  area  of  the  section  of  the 

duct  in  which  the  friction  is  produced. 

(h)  Finally,  we  have  to  deal  with  the  amount  of  work  spent  in  producing 

the  velocity  of  the  gas.     We  know  that  the  work  required  to  produce,  in  a 

W  v^ 
weight  W,  a  velocity  of  v  feet  per  second  is  — .  —  foot-pounds.      Now  if 

we  take  that  section  of  the  orifice  of  exit  at  which  the  motion  is  parallel  to 
the  sides  of  the  duct — i.e.  the  end  section  of  the  duct,  if,  as  in  the  figure,  there 
is  no  contraction,  but  if  there  be  contraction,  then  the  contracted  area  of 
orifice — and  if  we  represent  tliis  area  by  A,  then  if  V  be  the  flow  through 

this  orifice  in  cubic  feet  per  second,  the  velocity  of  the  air  issuing  is  —  feet 

A. 

per  second,  and  every  pound  which  issues  has  this  velocity.     Hence  the  work 

1  V^ 

spent  in  giving  the  requisite  velocity  v  to  every  pound  is  —  •^-^,orthehead 

AG  A. 

1  v^ 

spent    in  producing  velocity  is  -5-  'r^j  where  A  is  the  final  area  of  the 

orifice. 

"We  have  now  expressed  each  of  the  items  of  expenditure  of  head  in  terms 
of  the  square  of  the  flow,  and,  referring  to  equation  (2)  of  p.  59,  it  will  be 
found  that  the  different  terms  a,  b,  c,  d  .  .  .  are  all  accounted  for  under 
the  divisions  of  the  section  headed  by  the  same  letters  respectively.  In 
order,  therefore,  to  calculate  the  resistance  of  any  given  duct  from  its  shape 
and  dimensions,  we  have  to  substitute  in  equation  (2)  the  proper  values  for 
a,b,c  .  .  .  as  indicated  under  the  corresponding  headings,  and  add  them 
together  in  order  to  obtain  the  resistance  required. 

In  order  to  form  an  opinion  of  the  relative  magnitude  of  the  different 
items  representing  the  distribution  of  the  energy  of  the  head,  let  us  introduce 
numerical  values  for  a  shaft  of  circular  section  100  feet  long  and  1  foot  in 
diameter,  supposing  that  it  has  one  rectangular  bend  and  one  curved  bend 
of  90° ;  we  will  assume  the  coefficient  of  friction  to  be  "01. 

Taking  the  items  in  order  : 

1        /  1  12       ^\     V2 

=  -b  X 


1       /  1  "1 2         \     Y2 
(a)  Loss  at  orifice  of  entry  :  — —    ( -^-z,\    —  1 1    o  ="6  . . 


(0) 


No  sudden  changes  of  section. 


1       V^  V- 

{d)  Loss  at  rectangular  bend  :  -- — 

64"4 


a)^"e-G) 


V 


(e)  Loss  at  curved  bend  :  .  —  . =  -o   x 

64-4       2      ^y  ,,.,^^ 

(/)  Loss  at  exit.     (None) 


WABMING  AND   VENTILATION  71 

ition :  -01  x  100     JV^    _  Y 

(Hydraulic  mean  radius  I)     i.  x.  32-2  *    /ttN^  —  «  >^  (54.4 


G)     '"'(jy 


(^)  Loss  by  friction :       _      ^^    -01  x  100      JV^    _  V^ 

1          V^             V^ 
(h)  Expenditure  in  velocity :  — — ■  . „  = — -- 

Adding  these  together  get : 

fad       e       g      h\        ya 
IE)  =  l,-6  +  1  +  -5  +  8  +  1; ; 


11-1  X  4^2_ 


«*•*© 


lG-1     X    TT^ 


From  which  we  see  that  the  friction  of  the  duct  is  by  far  the  most  im- 
portant item.  The  resistance  comes  out  to  be  -28,  and  the  equivalent  orifice 
is  therefore :  

A  /        =  'ST  square  foot. 

V  27  X  -28 

If  the  end  of  the  shaft  be  covered  with  a  grating,  the  bars  and  frame  of  which 
occupy  one-half  of  the  area  of  the  duct,  we  must  include  an  additional  term. 

(under  the  heading/),  whose  magnitude  is  f—-l\    -—^  ^  ^j-^g^e 

^  ^   64-4  X  (^  j 

Y2 

<p  is  about  '75,  so  that  the  term  comes  out  3 2  >  ^^^  is  of  the  same  order 

''■'id 

of  importance  as  the  loss  by  friction  throughout  the  whole  tube. 


Summary  of  Causes  available  to  produce  Motion  of  Air  for  the  pibrposes  of 
Ventilation.     Calculation  of  Head  in  different  Cases 

21.  In  the  preceding  section  we  have  seen  that  the  motive  power  of  any 
ventilating  apparatus  may  be  numerically  represented  by  the  head  produced. 
When  the  head  is  known  the  calculation  of  the  horse-power  required  to 
maintain  a  circulation  of  specified  amount  is  simple,  for  we  have  already 
seen  that  the  head  If)  is  the  work  done  in  driving  one  pound  of  air  through 
the  shaft ;  and  hence,  if  the  apparatus  is  delivering  W  lbs.  per  second,  the 
work  done  per  second  is  lb  W  foot-pounds,  and,  taking  the  conventional  value 
of  a  horse-power  at  33,000  foot-pounds  per  minute,  or  550  foot-pounds  per 
second,  we  get  for  the  power  required  to  maintain  the  ventilation  If)  W/550 
horse-power.  It  may  be  more  convenient  to  express  the  power  in  terms  of 
the  volume  of  air  delivered ;  this  will,  of  course,  be  different  for  air  at 
different  temperatures  and  pressures,  and  may,  therefore,  be  different  at 
different  sections  of  the  flow  ;  but  if  A  be  the  density  of  the  air  at  any  section 
in  pounds  weight  per  cubic  foot,  at  which  the  volume  delivered  is  ascertained, 
and  V  the  volume  in  cubic  feet  delivered  there  per  second,  we  have  W  =  V  A , 
and  hence  the  horse-power  required  is  1b  V  A  /550. 

If  R  be  the  total  resistance  of  the  ducts  which  convey  the  air  to  and  from 
the  room,  we  have  from  p.  59,  lb  =  R  V^. 

To  take  a  numerical  instance  :  3,000  ctchic  feet  of  air  per  hour  being  the 


72  HYGIENE 

amount  required  for  efficient  ventilation,  for  each  person  in  a  room,  calculate 
the  Iwrse-poioer  required  to  supply  air,  for  100  persons,  assuming  that  the 
whole  head  for  the  cir  epilation  is  equivalent  to  that  due  to  the  pressure  of  one- 
tenth  of  an  inch  of  water. 

a' 
The  head  II)  corresponding  to  the  assigned  pressure  is        —    foot-pounds 

120  A 

per  pound,  p.  57,  where  A'  is  the  density  of  water  in  pounds  per  cubic  foot, 

and  A  the  density  of  air  (remembering  that  for  the  purpose  of  calculation 

all  lengths  must  be  expressed  in  feet  and  volumes  in  cubic  feet),  and  the 

flow  is   300,000   cubic   feet  per  hour,  or  83-3  cubic  feet  per   second ;  the 

required  horse-power  is,  therefore,      ^'  "^  ^'^''^  ^  ^ ,  or,  62-3  x  83-3       . 

^  ^  '       120  A   X  550  120  X  550 ' 

•078  H.P. 

The  total  resistance  of  the  ducts  necessary  to  supply  the  air,  with  the 

A  /  1 

given  head,  will  be  U)/ V-,  which  gives,    —  —  x  ■, — -- 
^  _  .  120a     (83-3)2- 

Taking  the  ratio  of  the  densities  of  au'  and  water  at  1  /  800,  the  numerical 

value  of  the  resistance  becomes  — —  x ,  or  -00096. 

120       (83"3) 

Assuming,  further,  that  the  resistance  of  inlets  and  outlets  is  the  same,  we 

get  the  resistance  of  each  -00048,  from  which  we  calculate  the  area  a  of  the 

equivalent  orifice  of  the  inlets  or  outlets  respectively  to  be  (by  the  formula  of 

p.  58):       

/  1  1000  1000       f,         ,,    ,  •      i  1  V 

^  =  ttJ =^ — ^TT^ 7^==  -v^.-  =  9  sq,  tt.  (approximately). 

^  27  X -00048      3x12xn/io       111  i        v  i'i  J/ 

This  example  shows  how  large  the  areas  of  inlets  and  outlets  must  be  to 
secure  adequate  ventilation  on  the  usual  basis  of  the  amount  of  fresh  air 
required,  unless  the  head  is  so  great  as  to  produce  very  strong  currents. 
For,  if  we  suppose  that  the  frictional  resistance  of  each  duct  were  such  as 
to  reduce  its  equivalent  orifice  to  half  the  apparent  orifice,  a  very  moderate 
estimate,  the  total  area  of  inlet  orifices  would  be  18  square  feet,  and  would 
require  9  ducts,  each  2  feet  x  1  foot  in  section,  and  the  velocity  of  entry 
would  then  be  about  4  feet  per  second.  Such  a  flow  is  denominated  in  the 
table  on  p.  74  '  a  gentle  wind.' 

All  apparatus  for  producing  ventilation  currents  may  be  regarded  as 
apparatus  for  producing  a  head.  We  shall,  therefore,  now  proceed  to  consider 
the  diflerent  ways  in  which  the  head  can  be  produced,  and,  as  far  as  possible, 
estimate  numerically  the  head  produced  under  given  conditions.  We  shall 
include  the  natural  agents  of  ventilation  with  the  artificial  apparatus,  in 
order  to  obtain  a  general  view  of  the  causes  which  serve  to  produce  ventila- 
tion. We  defined  ventilation  as  the  continuous  replacement  of  air ;  but,  in 
order  to  include  a  case  of  change  of  air  in  nearly  closed  spaces,  such  as  wells, 
closed  cesspools,  and  such-like,  we  shall  strain  the  definition  and  include  in 
this  survey  all  causes  of  change  of  air,  whether  continuous  or  intermittent. 
We  shall  group  these  causes  under  the  following  headings  : 

(a)  Variation  of  harometric  pressure  and  of  temperature.  Intermittent 
ventilation  of  enclosures. 

(h)  Direct  impact  of  wind  upon  an  opening. 

(c)  Wind  blowing  across  the  orifice  of  a  duct.  Ventilation  by  steam- 
jets. 

(d)  Head  produced  by  ventilating -fans. 

(e)  Head  proditced  by  bloioing  engines. 

(/)  Head  produced  by  hot  air  or  smoke  in  flues. 

Before  going  further,  it  may  be  well  to  remark  that,  as  far  as  the  motion 


WABMING  AND   VENTILATION  73 

of  the  air  in  ducts  is  concerned,  it  is  immaterial  whether  the  head  is  produced 
by  diminishing  the  pressure  at  the  exit  end  of  the  system  or  increasing  the 
pressure  at  the  inlet  end ;  but  the  difference  between  the  two  cases  is  of 
practical,  if  not  of  theoretical,  importance.  Methods  of  ventilation  found c  1  on 
the  former  plan  have  been  called  '  vacuum  '  methods  ;  whereas  those  founded 
on  the  latter  have  been  called  '  plenum  '  methods.  The  practical  distinction 
is  that  in  the  'vacuum  '  methods  (1)  the  crevices  and  chinks  of  a  system  act 
as  inlets,  and  (2)  fresh  air  can  be  introduced  directly  from  the  outside ;  whereas 
in  '  plenum '  methods,  the  crevices  act  as  outlets,  and  the  air  must  pass 
through  the  machine  used  to  compress  it.  There  is  thus  a  balance  of  advan- 
tages of  the  two  methods,  which  will  be  more  fully  discussed  in  a  later 
section.  In  the  sections  which  immediately  follow  we  shall  not  further  dis- 
tinguish between  them. 

(a)  Variations  of  harometric  pressure  and  temperature.    Intermittent 
ventilation  of  an  enclosure 

22.  Air  being  an  expansive  fluid,  it  must  be  kept  in  any  space,  which  may 
for  ordinary  purposes  be  regarded  as  closed,  by  the  pressure  of  the  external 
air  upon  the  small  openings  or  crevices,  balancing  the  internal  pressure,  and 
any  alteration  in  the  internal  or  external  pressure  upsetting  this  balance 
causes  a  flow^  of  air  through  the  crevices.  The  balance  of  internal  and 
external  pressure  is  upset  by  every  variation  of  the  external  barometric 
pressure  or  of  the  internal  temperature.  An  estimate  of  the  amount  of 
change  of  air  produced  by  oscillations  of  pressure  and  temperature  is  very 
easily  made.  A  fall  of  pressure  of  1  inch  causes  the  abstraction  of  57  cubic 
inches  of  air  from  every  cubic  foot  of  the  nearly  closed  space,  and  a  rise  of 
internal  temperature  of  V  F.  causes  the  expulsion  of  3^  cubic  inches. 
Changes  of  air  are  thus  effected  in  wells,  cupboards,  cases,  cellars,  cesspools, 
and  other  places,  even  when  they  have  no  apparent  openings.  And  similar 
causes  produce  an  expulsion  of  air  from  all  soils  which  are  porous  and 
contain  a  quantity  of  air  dependent  on  the  barometric  pressure.  As  the  air 
which  is  derived  from  such  sources  may  very  frequently  be  contaminated,  this 
effect  of  barometric  change  ought  not  to  be  overlooked.  It  is  more  particu- 
larly referred  to  in  Sir  Douglas  Galton's  '  Healthy  Dwellings.'  One  of  the 
most  striking  of  the  effects  attributable  to  this  cause  is  the  development  of 
firedamp  in  mines  during  periods  of  low  barometric  pressure,  to  which  many 
colliery  explosions  have  been  due.  On  a  small  scale  similar  developments  of 
pernicious  gases  may  occur  in  every  house  ;  and  we  therefore  mention  this 
instance  of  natural  ventilation  with  the  view  merely  of  suggesting  avoidance 
of  its  effects  by  the  provision  of  a  suitable  arrangement  for  the  artificial 
ventilation  of  all  such  enclosures  as  are  likely  to  furnish  a  supply  of  dele  • 
terious  air. 

{b)  Wind  hlotuing  directly  upon  an  opening 

23.  If  a  space  has  one  opening  which  is  exposed  directly  to  the  force  of  wind, 
the  pressure  at  that  opening  will  be  increased  by  an  amount  which  depends 
on  the  velocity  of  the  wind,  and  is,  indeed,  approximately  proportional  to  the 
square  of  the  velocity.  The  experiments  which  justify  this  assumption  have 
been  made  upon  comparatively  small  surfaces  exposed  to  the  action  of  wind ;  so 
that  in  applying  it  to  the  case  of  the  pressure  at,  for  instance,  an  open  window 
we  may  perhaps  be  pushing  the  application  further  than  is  justified.  But, 
in  any  case,  the  distribution  of  pressure  upon  the  irregular  surface  presented 
to  the  wind  by  an  ordinary  house  is  probably  so  irregular  that  any  calculation 
of  flow  from  the  wind  must  necessarily  be  extremely  rough.     It  may  be 


74 


HYGIENE 


useful,  liowever,  to  put  the  value  of  the  pressure  in  numbers,  as  we  maj 
obtain  thereby  at  least  a  rough  estimate  of  the  efficiency  of  the  wind  as  a 
ventilating  agent  in  comparison  with  others.  The  figures  in  the  following 
table  of  the  relation  between  the  velocity  of  the  wind  and  the  pressure  upon 
a  surface  at  right  angles  to  its  direction  are  given  in  Spon's  '  Dictionary  of 
Engineering  '  as  taken  from  the  Edinburgh  Encyclopasdia. 

Table  V. 


Equivalent 

Head  in 

Telocity  of 

Velocity  in 

Pressure  in 

height  of  a 

foot-pounds 

Character  of  the  wind 

wind  in  miles 

feet  per 

lbs.  weight 

column  of 

per  pound  of 

per  hour 

second 

per  sq.  foot 

water  in 
inches 

air  trans- 
mitted 

Hardly  perceiDtible     . 

1 

1-47 

•005 

-0009519 

■0635 

Just  perceptible 

•2 

2-93 

•020 

•003806 

•254 

Gentle  winds      .        .        •] 

3 

4-40 

•044 

-008373 

•558 

4 

5-87 

•079 

-01332 

•888 

5 

7-33 

•123 

•023 

1-53 

Pleasant  brisk  gale    . 

10 

14-67 

•492 

•092 

6-13 

Brisk  gale  .... 

l.j 

22-00 

1-107 

-21 

14-0 

Very  brisk .... 

20 

29-33 

1-968 

-368 

24-5 

25 

36-67 

3075 

-585 

39^0 

High  -wind          .        . 

30 

44-00 

4-429 

-84 

56^0 

35 

51-34 

6-027 

1-146 

76^4 

Very  high  .... 

40 

58-67 

7-873 

1-5 

100 

By  way  of  illustration  we  may  remark  that  according  to  the  table  the 
head  required  for  the  example  of  p.  72  could  have  been  supplied  by  wind 
impinging  fully  on  the  end  of  the  shaft  with  a  velocity  of  about  7  miles 
per  hour. 

We  have  been  proceeding  so  far  on  the  assumption  that  the  wind  affects 
one  end  only  of  the  ventilation  system.  Every  space  to  be  ventilated  has, 
however,  at  least  two  openings.  A  room  with  an  open  window,  for  instance, 
must  have  other  openings  if  the  air  is  to  pass  through  the  room.  The  other 
openings  which  correspond  to  the  exit  orifice  of  the  shaft  of  the  problem  on 
p.  72  we  have  assumed  to  be  entirely  free  from  the  action  of  the  wind.  In 
practice  this  will  hardly  be  the  case,  and  what  we  have  really  to  deal  with  is 
no  doubt  a  very  complicated  result,  namely  the  difference  of  action  of  the 
wind  upon  the  two  ends  of  the  ventilation  system.  If  by  any  fortuitous, 
combination  of  circumstances  the  effect  of  the  wind  were  the  same  on  both 
ends,  or,  what  comes  to  the  same  thing,  if  there  were  only  one  opening,  the 
effect  would  be  merely  a  corresponding  compression  of  the  air  in  the  interior, 
provided  we  could  leave  out  of  account  the  differences  of  pressure  at  different 
parts  of  the  aperture,  which,  however,  would  really  cause  very  large  replace- 
ment of  air.  It  will,  however,  be  instructive  to  consider  what  volume  of  air 
would  be  introduced  by  a  sudden  change  of  pressure  due  to  wind.  Let  us 
take,  for  instance,  the  pressure  due  to  10  miles  per  hour,  viz.,  approximately, 
y'^jth  inch  of  water.  This  would  force  through  the  opening,  to  bring  the  pres- 
sure in  the  interior  up  to  the  external  pressure,  only  one  4000th  part  of  the 
amount  of  air  in  the  mterior  space.  It  would  appear,  therefore,  that  the 
smoking  of  chimneys  in  gusty  weather  could  hardly  be  attributed  to  the  action 
of  the  wind  in  producing  increased  pressure  at  the  chimney-top,  but  may  be 
due,  in  part  at  least,  to  the  effect  of  the  wind  at  the  other  end  of  the  ventila- 
tion system  of  which  the  top  of  the  chimney  is  the  one  end.  In  the  com- 
plexity of  air-currents  that  must  be  produced  by  the  impact  of  the  wind  upon 
a  house,  the  variability  of  the  direction  and  magnitude  of  the  wind-head  is. 
not  by  any  means  surprising. 


WARMING  AND    VENTILATION 


75 


(c)  Wind  hloiving  across  an  aperture 

24.  If,  instead  of  being  set  at  right  angles  to  the  direction  of  the  wind, 
the  aperture  is  so  placed  that  the  wind  can  pass  over  it  without  entering  the 
duct,  the  effect  of  the  wind  is  to  diminish  the  air-pressure  at  the  orifice,  and 
so  produce  a  current  in  a  direction  opposite  to  that  which  is  set  up  when 
the  wind  impinges  directly.  This  effect  of  air  in  motion  is  an  instance 
of  a  hydrodynamical  result  of  considerable  interest  and  importance,  and  in 
some  cases  its  experimental  application  appears  at  first  sight  paradoxical. 
If,  for  example,  a  tube  be  provided  with  a  cup-shaped  mouthpiece,  and  a 
wooden  ball  be  placed  in  the  cup  of  such  a  size  that  the  ring  of  contact  is 
well  within  the  cup,  then,  when  a  rapid  current  of  air  is  driven  through  the 
tube  and  escapes  between  the  ball  and  the  cup,  the  air-pressure  in  the  space 
between  the  ball  and  cup  is  so  much  diminished  that  the  ball  will  hang 
suspended  from  the  tube  as  long  as  a  sufficiently  strong  blast  is  maintained.' 
We  may  illustrate  the  same  principle  in  a  manner  which  shows  its  applica- 
tion to  ventilation  by  the  experiment  described  below. 

Thus,  when  a  current  of  air  is  driven  into  a  room  by  means  of  a  fan,  as 


Fig.  14. 


represented  in  fig.  14,  it  might  be  supposed  that  the  pressure  of  air  in  the 
middle  of  the  current,  near  the  nozzle,  is  greater  than  elsewhere  in  the  room. 
The  precise  opposite  is,  however,  the  case ;  the  air-pressure  in  the  current  is 
less  than  elsewhere,  and  least  where  the  velocity  is  greatest.  This  may  be 
experimentally  verified  by  introducing  into  the  current  one  end  of  a  tube 
A,  the  other  end  of  which  dips  into  water  which  is  screened  from  the  direct 
action  of  the  air-current.  The  general  plan  of  the  experiment  is  represented 
in  fig.  14.  The  passage  of  the  air  across  the  mouth  of  the  vertical  tube  causes 
the  water  to  rise  slightly  in  the  lower  part  of  the  tube,  showing  that  the 
pressure  in  the  current  is  less  than  that  of  the  air  of  the  room.  The  rise 
of  liquid  is  exaggerated  in  the  figure ;  it  is  of  course  proportional  to  the 
difference  of  pressure  (P  —  p)  betAveen  the  air  in  the  bottle  B  and  the 
interior  of  the  current. 

In  some  rough  experiments,  the  velocity  of  the  air  across  an  open  tube  was 

'  This  form  of  the  well-known  hydrodynamical  paradox  has  recently  been  brought  out 
by  an  American  firm  as  a  scientific  toy. 


76 


BYGIENE 


I 


measured  by  means  of  the  air-meter  (p.  105),  and  the  diminution  of  pressure 
produced  was  determined  by  finding  the  height  to  which  the  water  rose  in 
the  tube,  inchning  the  tube  considerably  in  order  to  make  the  reading  more 
sensitive.  Observations  were  taken  with  four  different  velocities — viz.  8-7, 
10-8,  13"3,  and  17*8  feet  per  second  respectively.  The  results  show  a 
dimmution  of  pressure  at  the  orifice  proportional  to  the  square  of  the  velocity 
of  the  air  ;  and  if  the  relation  between  the  head  H)  so  produced  and  the 
velocity  v  be  represented  by  the  equation  1b  =  ^  v'-,  the  mean  value  of  the 
constant  k  deduced  from  the  experiments  is  -0155.  Theoretically,  when  the 
velocity  of  air  at  any  point  in  a  jet  is  v,  the  head  or  difference  of  pressure, 
expressed  as  the  height  of  a  column  of  air,  between  the  point  and  a  point  of 
the  jet  where  the  motion  has  practically  ceased,  is  given  by  the  formula 

•jf)  =  ^  =    '^1=  -0155  v^,  provided  we  neglect  changes  of  density  of  the 

2g      64*4 
air  ;  so  that  it  appears  from  the  above  experiments  that  the  head  actually 
produced  at  the  end  of  the  narrow  tube  there  used  corresponds  precisely 
with  the  theoretical  head  calculated  in  the  manner  explamed  above. 

There  seems  no  reason  for  supposing  that  the  effect  produced  by  wind 

blowing  across  an  orifice 
is  anything  else  than  the 
difference  of  pressure  cor- 
responding to  that  in  the 
interior  of  the  jet ;  and 
it  may,  therefore,  be 
assumed  to  be  the  same, 
however  the  orifice  may 
be  placed  with  regard  to 
the  air-current,  provided 
that  it  is  not  exposed  to 
the  direct  impact  of  the 
air.  Thus  leaving  out  of 
account  changes  in  the 
current  produced  by  the 
building  from  which  the 
duct  leads,  and  assuming 
that  the  inlet  of  the  duct 
is  entirely  protected  from 
the  wind,  we  may  repre- 
sent (in  feet)  the  head  1) 
produced  as '01 55^^^  where 
V  is  the  velocity  of  the 
wind  in  feet  per  second.  So 
that,  for  instance,  wind  at 
the  rate  of  15  miles  an 
hour  will  produce  a  head 
equivalent  to  the  pressure 
of  the  eighth  of  an  inch 
of  water. 

The  production  of  a 
head  for  ventilation  by 
the  motion  of  air  over  the 
mouth  of  a  tube  is  the 
object  of  many  extraction  ventilators  and  cowls.  A  primary  cause  of  un- 
certainty in  their  action  when  fixed  to  buildings  is  the  variability  in  the  direc- 


WABMING  AND    VENTILATION 


77 


tion  of  wind- currents  under  the  influence  of  the  surfaces  of  the  building  itself. 
Many  forms  of  cowl  have  been  designed  to  render  the  ventilators  serviceable  for 
any  direction  of  wind,  of  which  there  are  two  characteristic  types — viz.  those 
with  fixed  vanes  and  those  with  a  rotating  cowl.  Of  the  former  type  Boyle's 
ventilator  (fig.  15)  may  be  regarded  as  a  specimen ;  the  vanes  are  fixed  as 
represented  in  fig.  16,  so  that,  from  whatever  direction  the  wind  may  come,  the 


Fig.  16. 


Fig.  17. 

motion  of  the  air  is  always  tangential  to  the  opening  of  the  shaft ;  the  latter 
type  may  be  represented  by  Banner's  cowl  (fig.  17),  which  sets  by  means  of  a 
wihd-vane  so  that  the  shaft-opening  which  is  carried  round  by  the  wind- vane 
always  faces  away  from  the  wind.  In  all  forms  of  cowl  the  head  is  very 
variable,  and  may  be  very  small,  and  is  liable  to  be  completely  over-weighted 
by  some  other  head.  In  such  a  case  the  motion  of  the  air  is  reversed,  and 
the  ventilator  acts  as  an  inlet  (see  below,  p.  101). 

In  order  to  produce  a  current  of  air  along  a  tube,  a  steam -jet  is  sometimes 
directed  along  it.  Thus  at  the  Lower  Moor  Colliery,  Oldham,  '  an  apparatus 
consisting  of  72  vertical  pipes,  5  feet  long  and  7  inches  in  diameter,  was 
fitted  to  an  iron  frame  at  the  top  of  the  upcast  shaft.  Into  each  was 
inserted  a  steam-pipe  having  a  nozzle  of  T;\ths  inch  in  diameter,  supplied 
with  steam  at  38  lbs.  pressure.  This  rough  apparatus  exhausts  16,000 
cubic  feet  a  minute.'  The  forced  draught  of  a  locomotive  furnace  is  another 
instance  of  the  same  kind  of  action.  The  head  in  these  cases  is  due  to  the 
high  velocity  vidth  which  the  steam  issues  from  the  nozzle,  producing  a  con- 
siderable lowering  of  pressure  in  the  neighbourhood  of  the  orifice.  An 
arrangement  of  this  kind  was  at  one  time  employed  for  the  ventilation  of  the 
House  of  Lords,  but  has  been  abandoned.  The  method  depends  upon  the 
same  principle  as  the  production  of  head  by  wind  across  an  aperture,  but  we 
are  unable  to  give  any  simple  plan  of  calculating  the  head  produced  in  any 
specified  case. 

(d)  Head  produced  by  Ventilating  Fans 

25.  In  order  to  produce  a  head  for  the  ventilation  of  mines  and  large 
buildings,  a  centrifugal  fan  is  now  not  infrequently  used.  A  fan-wheel  is 
formed  by  a  number  of  vanes  attached  to  an  axle.     When  the  wheel  is 


78 


HYGIENE 


rotated  air  is  carried  along  by  the  vanes  in  their  motion ;  as  the  particles  of 
air  slip  along  the  surface  of  the  fan  towards  the  tips  of  the  vanes  their 
velocity  is  accelerated  and  they  finally  leave  the  fan-wheel  with  a  taxigential 
velocity  closely  approximating  to  the  velocity  of  the  tips  of  the  vanes.  Ihe 
general  result  of  the  rotation  of  the  fan  is  a  motion  of  air  from  the  axis  to  the 
outside  edge  of  the  wheel,  and  a  diminution  of  pressure  near  the  axis  is  the 
result.  If  the  wheel  revolves  in  the  open  air,  the  air  leaves  the  wheel 
tangentially  at  all  points  of  the  periphery,  but  by  enclosing  the  fan-wheel 
in  a  circular  cover  with  openings  at  the  axle  and  a  tubular  aperture  at  the 
periphery,  the'  delivery  of  air  may  be  made  to  take  place  along  the  tube,  and 
the  effect  of  the  fan  is  thereby  considerably  increased.      The  axis  of  the 

wheel  is  placed  excentrically  with 
reference  to  the  circle  which  forms 
the  general  outline  of  the  cover,  so 
that  the  clearance  between  the  re- 
volving vanes  and  the  cover  gradu- 
ally increases  up  to  the  tube  of  dis- 
charge, and  by  this  arrangement 
part  of  the  kinetic  energy  of  the 
rapid  motion  of  the  air  is  devoted  to 
increasing  the  head  instead  of  bemg 
wasted  in  producing  eddies  in  the 
surrounding  space.  Arranged  in  this 
way,  the  fan  draws  air  from  the 
apertures  round  the  axle  and  throws 
it  out  by  the  delivery  tube.  Accord- 
ing to  M.  Murgue '  the  most  effective 
type  of  fan  is  M.  Guibal's  (fig.  18), 
the  peculiarities  of  the  most  modern 
form  of  which  are  :  (1)  the  size  of  the  delivery  aperture  can  be  adjusted  by  a 
sliding  door  ;  (2)  the  aperture  is  provided  with  a  trumpet-shaped  mouthpiece, 
so  that  the  air  delivered  is  kept  confined  until  its  velocity  is  relatively  small, 
when  it  passes  into  the  atmosphere ;  and  (3j  the  vanes  are  so  shaped  that 
they  are  at  right  angles  to  the  periphery  at  their  tips,  but  tangential  to  the 
circular  aperture  at  the  axle,  so  that  the  air  slides  on  to  the  vanes  without 
loss  of  energy  in  eddies.  The  theory  which  M.  Murgue  sets  forth  for  venti- 
lating fans  enables  one  to  see  how  the  efficiency  of  machines  of  different 
types  may  be  compared.  On  his  view,  the  effective  head  h  which  a  ventilating 
fan  produces  diminishes  as  the  volume  of  air  drawn  through  it  increases, 
that  is,  as  the  area  of  the  apertures  is  increased.  The  limiting  value  which 
the  head  would  reach  if  the  areas  were  reduced  to  zero  (when  the  fan 
was  simply  mamtaining  a  difference  of  pressure  between  the  axle  and  the 
delivery  tube  without  any  air  being  allowed  to  flow  through)  is  1b  ;  the  differ- 
ence 1b  -  /z-,  or  ho,  is  the  head  required  to  maintain  the  flow  through  the 
machine  itself  or  loss  of  head  in  the  machine. 

According  to  M.  Murgue,  in  a  perfectly  designed  fan,  working  in  a  cover 
by  which  the  whole  of  the  kinetic  energy  of  the  motion  of  the  air  on  leaving 
the  vanes  is  collected  and  devoted  to  increasing  the  head,  the  total  head 
developed  by  the  fan  is  ^c^/g,  where  w  is  the  velocity  of  the  motion  of  the  tips 
of  the  vanes — i.e.  w  r — where  oj  is  the  angular  velocity  of  rotation  of  the  fan 
wheel,  and  r  is  the  radius  of  the  vane.  But  in  consequence  of  the  imper- 
fection of  the  fan  the  head  developed  cannot  be  taken  as  being  the  full 

'  Theories  and  Practice  of  Centrifugal  Ventilating  Macliines,  translated  by  A.  L. 
Steavenson. 


WABMING  AND    VENTILATION  79 


u"^ 


theoretical  value,  but  may  be  put  equal  to  K  -    where  K  is  a  factor  less  than 

unity  depending  on  the  arrangement  of  the  fan.  In  a  fan  without  cover  K 
cannot  exceed  -5.  The  value  of  K  is  one  important  element  in  the  specifica^ 
tion  of  the  efficiency  of  a  fan,  and  can  only  be  determined  indirectly  by 
experiments,  as  we  shall  show. 

We  have  already  seen  that  the  flow  of  air  through  a  mine,  or  a  ventilating- 
shaft,  or  a  machine,  can  be  represented  by  the  flow  of  air  through  an  orifice  in 
a  thin  plate  if  the  area  of  the  orifice  be  properly  chosen.  Thus,  if  the  ventilat- 
ing shaft  be  equivalent  to  an  orifice,  area  a,  in  a  thin  plate,  and  Jl  be  the  head 
required  to  maintain  a  flow  of  air  at  the  rate  of  V  cubic  feet  per  second,  we 
have 

Y  =  -65as/2gh 


'65  being  the  coefficient  of  contraction  on  1  I 

passing  through  the  orifice.     Now  if  we  I  I 

represent   the  motion  of  air  through  a  o  «-  < — 

ventilating-shaft  as  a  flow  through  an  1  1 

equivalent   orifice,  a  (fig.  19),    and   the  I j 

motion  through  the  fan  as  flow  through  ^^°-  ^^■ 

an  equivalent  orifice,  o,  we   get,  if  Jiq  is  the  head  required  for  the  second 

orifice,  

V  =  -65 0  s/2gho 

The  value  of /z-o,  the  loss  of  head  on  passing  through  the  fan,  is  the  second 
important  element  in  the  determination  of  the  efficiency  of  a  fan.  When  we 
look  into  the  matter  further  we  shall  see  that  the  value  of  h^  depends  also  upon 
the  flow  of  air ;  and  this,  as  we  have  already  seen,  depends  on  the  resistance 
offered  to  the  motion  of  the  air  through  the  mine  or  shaft,  and  hence  upon 
the  area  of  the  orifice  a,  in  a  thin  plate,  which  offers  the  same  resistance  to 
the  motion.  In  order,  therefore,  to  test  the  efficiency  of  a  fan,  we  must  be 
able  to  observe  its  effect  when  applied  to  draw  air  through  different  equivalent 
orifices.  We  may  secure  this  by  making  the  fan  draw  air,  not  through  an 
actual  mine  or  ventilation  system,  but  into  a  chamber  through  an  orifice  the 
size  of  which  can  be  adjusted  to  any  required  magnitude,  each  different  size 
of  orifice  representing  a  different  system.  We  are  able  to  observe  (i.)  the  velocity 
of  air  delivered  by  the  fan,  and  hence  the  rate  of  flow,  V  ;  (ii.)  the  area  of  the 
equivalent  orifice  a  ;  (iii.)  the  effective  head  h  (the  difference  of  pressure  in 
lbs.  weight  per  square  foot  between  the  air  in  the  chamber  and  outside  divided 
by  the  density  of  air) ;  (iv.)  the  velocity  of  the  tips  of  the  vanes,  u.  Con- 
necting these  quantities,  we  have  the  following  equations  : — 


whence 


v  = 

•65a  s/2gh 

h  = 

•65  0  s/2ghQ 
h  +  ho 

9 

V  =  -65 

From  observations  of  the  magnitudes  enumerated  above  the  value  of  o 
can  be  found  for  the  machine,  and  thence  the  value  of  K  determined,  as 


80 


HYGIENE 


likewise  the  values  of  ho  and  h  for  the  different  values  of  the  equivalent 
orifice  a.  ^^'Llen  these  have  been  determined,  the  values  of  h  and  V  can  be 
represented  on  a  diagram  by  curves,  of  whicli  the  ordinates  are  h  and  V  re- 
spectively and  abscissiB  a,  !Such  curves  are  called  characteristic  curves  for  the 
fan,  as  suggested  by  the  Commission  on  Ventilation  of  the  district  of  Gard. 
M.  Murgue  adds  a  table  of  the  value  of  K  (sometimes  determined  only  to  a 
rough  approximation),  deduced  from  the  published  observations  upon  fans  of 
various  descriptions.  The  values  vary  between  -1  for  some  machines  without 
cover  to  "7  for  machines  of  the  improved  Guibal  type.  The  best  machines, 
therefore,  produce  a  head  three-quarters  of  the  maximum  possible. 

26.  Another  method  of  producing  by  mechanical  means  a  head  for  ventila- 
tion is  the  rotation  of  a  wheel  with  inclined  vanes,  by  which  the  air  is 
made  to  pass  transversely  through  the  wheel  parallel  to  the  axis  of  rotation. 
The  action  in  this  case  is  the  direct  converse  of  the  action  of  a  windmill, 
and  practically  amounts  to  driving  the  windmill  in  order  to  produce  a  wind. 
These  machines  during  a  revolution  cut  off  a  portion  of  the  air  from  the 
one  side  of  the  wheel  and  transfer  it  through  the  wheel,  the  relative  motion 
being,  roughly  speaking,  similar  to  that  produced  by  the  action  of  a  screw.  In 
some  forms  the  vanes  are  helicoidal,  when  the  analogy  is  still  closer.  M. 
Murgue  discusses  the  theory  of  these  machines  in  the  work  already  quoted, 
and  classifies  them  as  woi'king  by  direct  impulsion.  The  formulae  arrived  at 
are  identical  in  form  with  those  given  for  centrifugal  machines.  For  those 
discussed  by  M.  Murgue  the  coefficient  K  varies  between  -05  and  "2,  so  that 
they  are  much  less  efficient  in  producing  head  than  the  centrifugal  machines  ; 
but  for  ventilations  requiring  a  large  supply  of  air  at  no  considerable  head 
they  may  be  as  effective. 

The  form  which  has  been  frequently  applied  to  the  ventilation  of  buildings 
is  Blackman's  air  propeller^  a  sketch  of  which  is  given  in  fig.  20.     According 

to  the  statement  of  the  company  supply 
ing  it,  it  gives  about  12,000  cubic  feet  per 
minute  per  horse-power  for  the  largest  size, 
and  about  6,000  cubic  feet  per  minute  per 
horse-power  for  the  smaller  sizes  ;  but  we 
may  presume  that  in  this  case  the  only 
resistance  that  is  contemplated  is  that 
offered  by  the  machine  itself,  and  the 
amount  of  air  supplied  through  the  ducts 
of  any  ventilation  system  will  depend  upon 
the  resistance  of  the  ducts  as  well  as  that 
of  the  machine,  just  as  in  the  case  of  the 
centrifugal  fan  ;  and  the  essential  charac- 
teristics of  the  fan  can  only  be  determined 
by  the  experimental  method  indicated 
above. 

in  the  matter  of  ventilation  by  fans  is 
the  question  of  the  mechanical  efficiency  of  the  apparatus.  The  power  used 
in  discharging  V  cubic  feet  of  air  per  second  from  a  head  If)  is  1b  V  A  foot- 
pounds per  second,  where  A  is  the  density  of  the  air  supplied.  In  calculating 
the  mechanical  efficiency  of  fans  and  other  ventilating  machines,  M.  Murgue 
substitutes  for  1[5  the  theoretical  head  of  the  machine  and  not  the  effec- 
tive head  h,  thereby  including  in  the  useful  work  of  the  machine  that  spent 
in  forcing  the  air  through  the  machine  itself.  Comparing  on  this  assumption 
different  ventilating-machines,  he  obtains  the  foUowmg  results  for  the  ratio 
of  useful  work  done  to  work  supplied  to  the  machine. 


Fig.  20. 


An   important   consideration 


WABMING  AND   VENTILATION 


81 


Mean  mechanical  eflSciency  of  ventilation  by  direct  impulsion  '        .        ,        .        .     -260 
,,  „  ,,  „  centrifugal  force,  without  cover  .         .     -278 

„  „  „  „  with  cover  and  chimney      .        .         .     -467 

(e)  Head  produced  by  blowing  machines 
27.  A  number  of  machines  have  been  designed  and  used  for  supplying  an 
air-blast  to  furnaces,  and  for  ventilation,  the  principle  of  which  is  widely  dif- 
ferent from  that  of  the  machines  which  have  hitherto  been  discussed.  The 
simplest  type  may  be  represented  as  an  air-pump  or  bellows  driven  by  the 
piston  of  a  steam-cylinder.  The  air-pump  is  simply  a  barrel  with  two  valves, 
one  opening  outwards,  the  other  inwards,  with  a  piston  sliding  in  the  barrel. 
As  the  piston  moves  backwards  and  forwards  the  valves  alternately  open  and 
shut,  and  the  air  is  drawn  in  at  one  valve  and  forced  out  at  the  other.  The 
barrel  of  the  air-pump  may  be  made  as  large  as  we  please — provided  we  have 
power  to  drive  it — and  by  arranging  it  like  the  cylinder  of  a  steam-engine  a 
delivery  of  air  may  be  secured  both  by  the  back  and  forward  stroke  ;  and  with 
several  pumps  on  the  same  crank,  each  delivering  into  an  air-chamber  from 
which  outlets  proceed  for  the  distribution  of  the  air,  a  steady  flow  through  the 
ventilation  system  may  be  obtained.  Drawings  and  particulars  of  various 
blowing  machines  are  given  in  the  supplement  to  Spon's  '  Dictionary  of  Engin- 
eering '  (art.  Blowing -machine),  and  a  form  specially  designed  for  ventilation 
by  Cunningham  is  mentioned  in  the  article  *  Ventilation  '  in  the  '  Encyclo- 
paedia Britannica.'  One  source  of  loss  of  energy  in  the  working  of  these 
machines  lies  in  the  fact  that  the  motion  of  the  piston  has  to  be  reversed  with 
every  stroke,  and  however  light  the  piston  may  be  made  its  mass  is  large  com- 
pared with  the  mass  of  air  to  be  moved.  The  loss  Inay  be  reduced  by  special 
design  of  the  machine  which  drives  the  piston,  but  cannot  be  entirely  obviated, 
so  that  for  the  purposes  of  producing  a  current  of  air  a  rotary  piston  seems 
much  more  suitable.  Boots' 
blower,  fig,  21,  is  a  machine 
which  is  worked  by  rotating 
pistons.  Two  pistons,  each 
shaped  like  a  figure  of  8,  are 
worked  on  parallel  axles  in  a 
box  with  two  openings  ;  the 
box  is  formed  of  two  half  cy- 
linders separated  by  two  flat 
portions,  and  in  these  two  flat 
portions  the  holes  for  entry 
and  delivery  are  made.  As  the 
pistons  rotate  the  air  is  driven 
through  the  apparatus,  Cun- 
ningham has  also  modified 
this  machine  for  ventilation. 
In  all  machines  of  the 
air-pump  or  rotary  piston 
type  it  is  evident  that  a  de- 
finite volume  of  air  is  trans- 
mitted at  each  stroke.  When 
this  volume  is  known — and  it 
may  be  calculated  from  the 
dimensions  of  the  machine— the  volume  V  of  air  transmitted  per  second  is 
known  from  the  speed  of  revolution,  and  whatever  head  is  needed  to  drive  that 


VOL,   I. 


See  above,  p.  80. 


82  HYGIENE 

volume  will  be  supplied  fi-om  tlie  source  of  power  which  drives  the  fan.  A 
machine  of  this  description  can  therefore  be  tested  by  replacing  the  ventilation 
system  by  an  orifice  in  the  air-chamber  whose  area  is  known,  and  calculating 
the  bead  required  from  the  formula,  


*=-'^°''-v/^"' 


and  measuring  V  for  a  given  speed  of  rotation. 

The  work  done  per  second  is  V  1l3  A,  and  if  we  measure  the  power  required 
to  drive  the  machine  we  get  the  efficiency,  as  the  ratio  of  the  effective  work 
per  second  to  the  whole  power  required  to  drive  the  fan. 

(/)  Head  produced  in  hot-air  and  smoke  flues 
28.  In  the  case  of  a  vertical  hot-air  flue  we  can  calculate  the  head  in  the 
following  manner.  The  hot  air  rises  because  its  density  is  less  than  the  density 
of  the  air  surrounding  the  flue.  Let  us  suppose  the  density  of  the  air  in  the 
flue  to  be  uniform  throughout  the  flue  and  equal  to  A'  lbs.  per  cubic  foot,  and 
the  density  of  the  air  surrounding  the  flue  to  be  Hkewise  uniform  and  equal 
to  A  lbs.  per  cubic  foot.  Then  every  cubic  foot  of  volume  of  air  in  the  flue 
will  be  acted  upon  by  a  force  equal  to  the  weight  of  (  A  —  A')  lbs.,  and  hence 
the  total  force  on  the  air  in  the  flue  is  (A  —  A')  A  H  pounds  weight,  where 
A  is  the  area  of  the  flue  and  H  its  height.  If  the  air  is  passing  up  the  flue 
at  velocity  v  feet  per  second  (A  —  A'),  A  Hv  foot-pounds  of  work  per  second 
will  be  done  by  the  force.  But  this  corresponds  to  the  delivery  oi  Av  A' 
pounds  of  air  ;  hence  the  head,  or  work- equivalent  of  the  flue  per  pound  of  air, 
•    A  — A'tt 

is  ; — H. 

A' 

We  notice  about  this  expression  that  the  head  depends  merely  upon  the 
density  of  the  air  inside  and  outside,  and  upon  the  vertical  height  of  the  flue. 
Though  we  made  use  of  the  area  of  the  flue  in  the  calculation,  it  has  disap- 
peared from  the  result,  and  we  may  rightly  conclude  that,  provided  the  density 
of  the  air  is  the  same  throughout,  the  head  will  not  depend  upon  the  area, 
shape,  or  size  of  the  flue,  but  merely  upon  the  difference  of  level  of  the  open- 
ing at  the  top  and  bottom.  There  may  be  any  number  of  bends  and  con- 
strictions and  horizontal  portions  :  these  affect  the  resistance  ;  they  do  not 
affect  the  head,  except  possibly  indirectly,  by  altering  the  distribution  of  tem- 
perature and  thereby  the  density  of  the  air. 

The  difference  of  density  is  produced  by  raising  the  temperature  of  the 
air  in  the  flue  above  that  of  the  outside  air  either  by  supplying  heat  to  the 
air  as  it  passes  into  the  flue  at  the  bottom,  as  in  an  ordmary  chimney,  or  by 
supplying  heat  to  the  air  of  the  space  to  be  ventilated  and  letting  the  air  so 
heated  pass  into  the  flue,  as  in  the  case  of  an  ordinary  ventilation  flue  un- 
provided with  any  special  supply  of  heat. 

As  the  temperature  of  the  air  in  the  flue  is  much  more  easUy  measured 
than  the  density,  we  will  express  the  head  in  terms  of  the  temperature.  We 
have  already  (§  8)  explained  how  the  density  may  be  calculated  from  the 
temperature.     If  T  be  the  temperature  of  the  air  in  the  flue,  and  t  that 

of  the  external  air,  in  Fahrenheit  degrees,  — =-rz^T — fhj 

A      459 -fT 

whence  we  find  the  head, 

*=J9"> W 

The  head  is  therefore  proportional  to  the  difference  of  temperature  of  the  in- 
ternal and  external  air,  and  the  flow  will  be  upwards  if  the  internal  temperature 
is  greater  than  the  external,  but  downwards  if  the  reverse  is  the  case.  For  the 


WABMING  AND   VENTILATION  83 

purposes  of  accurate  calculation  the  external  temperature  should  be  measured, 
but  for  very  rough  computation  we  shall  not  be  far  wrong  if  we  assume  the 
external  temperature  to  be  always  at  41°  F.  and  the  head  of  a  hot-air  flue  to 
be  therefore  5-oirth  part  of  the  product  of  the  difference  of  internal  and  external 
temperatures,  and  the  difference  of  level  of  the  top  and  bottom  openings. 

It  follows  from  this  calculation  that  any  variation  in  the  temperature  of 
the  air  contained  in  a  chimney  will  cause  a  change  in  the  ventilation  head ; 
now  the  temperature  in  the  chimney  will  fall  if  the  flow  of  cold  air  into  it  be 
increased  by  diminishing  the  resistance  of  the  inlet  ducts.  The  head  is 
therefore,  strictly  speaking,  not  independent  of  the  flow,  although  it  may  be 
assumed  to  be  so  if  the  change  is  a  very  small  fraction  of  the  whole  flow  ; 
thus  if  a  large  block  of  buildings  be  ventilated  by  one  very  large  chimney-stack 
the  head  might  be  assumed  to  have  remained  constant,  although  the  resistance 
of  the  entry  inlets  of  one  room  had  been  doubled.  If  the  shaft  is  long,  a 
small  change  in  the  flow  will  not  affect  the  temperature  very  much  at  first, 
for  heat  will  be  communicated  from  the  hot  sides  of  the  chimney  ;  but  ulti- 
mately a  permanent  change  in  the  flow  will  correspond  to  a  permanent  change 
in  the  temperature  and  therefore  in  the  head.  We  have  been  of  course  tacitly 
assuming  that  the  supply  of  heat  has  been  constant ;  such  a  condition  would 
hardly  be  realised  with  a  coal  fire  at  the  foot  of  a  chimney,  but  it  would  be  so 
if  the  heat  were  furnished  by  the  combustion  of  a  number  of  gas  jets  with  a 
constant  supply  of  gas.  In  such  a  case  we  might  be  able  to  express  the 
head  in  terms  of  the  heat-supply  and  the  flow,  which  can  be  done  as  follows. 
Let  ©  be  the  amount  of  heat  supplied  per  second,  and  let  the  flow  of  cold  air 
to  the  chimney  be  V  cubic  feet  per  second;  the  weight  of  air  warmed  per  second 
will  be  V  A .  It  is  warmed  at  practically  constant  pressure,  so  that  the  specific 
heat  is  '238,  and  the  heat  used  per  second  is  '238  (T  — ^)V  A  =0, 

from  which  we  get  (by  equation  8,  p.  80) 

a. 
or  ID 


or  1bV= 


238(459 -fi)V  A 
©H 


•238(459  +  0  A* 


Thus  the  head  is  inversely  proportional  to  the  flow. 

Let  us  apply  this  equation  to  calculate  roughly  the  head  due  to  combus- 
tion in  a  special  case. 

To  find  the  Head  of  Air  toitJi  an  Open  Gas  Fire  burning  20  Cubic  Feet 

of  Gas  per  hour 

1  lb.  of  gas  produces  18000  lb.  F.  units. 

The  density  of  coal  gas  is  -0418  lb.  per  cubic  foot. 

The  weight  of  gas  burned  is  therefore  equal  to  ^^— ^^ =-00023  lb.  per 

second. 

T  may  be  taken  as  41°  F. ;  and  assuming  all  the  heat  to  go  up  the 
chimney  we  have 

-p^^TT  ;00023xl8000_ 
""         •238x500xVA 

=^x-035. 

o2 


84 


HYGIENE 


In  order  to  determine  the  head  we  require  to  know  the  weight  of  air 
passing  per  second,  which  must  be  determined  by  observation  of  the  velocity 
of  transmission,  but  if  the  area  a  of  the  orifice  to  which  the  chimney  is  equi- 
valent be  known,  and  likewise  the  equivalent  area  a'  for  the  inlets,  we  get  (see 
p.Gl) 


1l3=2-35     t  + 


a 


V2 

and.  if  W  be  the  weight  of  air  delivered  W=V  A. 
^Yhence  we  get 

j_    2RA^g     -0036 


^V3= 


/  1      J^>^   2-35 


=•00050 


H 


-„+- 


Hence  for  a  given  quantity  of  gas  burned  per  hour  the  weight  of  air  carried 
up  the  chimney  varies  as  the  cube  root  of  the  height  of  the  chimney,  and  as 
the  cube  root  of  the  square  of  area  of  the  equivalent  orifice  if  the  air  be  allowed 
free  access  to  the  base  of  the  shaft,  i.e.  if  «'  may  be  regarded  as  indefinitely 
great.  This  equation  may  be  used  to  determine  the  smallest  value  of  «',  or 
the  area  of  the  inlets,  that  is  consistent  wdth  the  delivery  of  a  given  weight  of 


Table  VI. — Production  of  Head  of  given  Numekical  Value  bx  Vapjous  Agents. 


Head  or  equivalent 

pressvire 

Conditions  necessary  to  produce  the  Head 

-f.  ~t:  -^ 

.  ^ 

O         c^ 

SS 

la 
.si 

1P 

<4-l    cj    3 

Velocity  of  tips 

Velocity  of 
periphery  of 

0-2  a 

42  «» 

.2  '^■ 

2.2 

2^ 

go 

U   Pi 

<u  bo 
n'.'S 

■2  "2  ^ 

•"  o  " 

"2  ^a 

o  a  o 

^o§ 

o  c-y 

of  vanes  of 

centrifugal  fans, 

§25 

wheel  of  direct 

impulsion  fans, 

§26 

a  o 
>-  o 

II 

u 

f^  & 

tua 

■3  2  » 

>a 

k  ^  ^ 

^  ■* 

fk 

W  ft-s 

(>g 

p. 

Worst 

Best 

Worst 

Best 

•01 

•052 

•670 

5-71 

6-57 

14-7 

5-55 

20-8 

10-4 

•00152 

49-4 

•02 

•104 

1-34 

8-10 

9-29 

20-8 

7-85 

29-4 

14-7 

•00302 

57-7 

•03 

•156 

2-01 

9-78 

11^4 

25-4 

9-62 

36-0 

18-0 

•00454 

63^1 

•04 

•208 

2-68 

11-4 

13-1 

29-4 

11-1 

41-5 

21-0 

•00606 

74-5 

•05 

•259 

3-35 

12-5 

14-7 

32-8 

12-4 

46-4 

23-2 

•00757 

82-9 

•06 

•311 

402 

13-7 

16-5 

36-1 

13-6 

50-9 

25-4 

•00909 

91-3 

•07 

•363 

4-69 

14-8 

17-5 

38-9 

14-7 

551 

27-5 

•0106 

99-6 

•08 

•405 

5-36 

15-6 

18-5 

41-5 

15-7 

58-8 

29-4 

•0121 

108-0 

•09 

•467 

6-03 

16-7 

19-9 

44-1 

16-6 

62-3 

31-2 

•0136 

116 

•1 

•519 

6-70 

17-6 

20-7 

46-4 

17-5 

65-7 

32-8 

•0152 

124 

•2 

1-04 

13-4 

24-8 

29-4 

65-7 

24-8 

91-8 

46-4 

•0302 

208 

•3 

1-56 

20-1 

30'2 

36-0 

80-5 

30-4 

114 

56-9 

•0454 

292 

^ 

•4 

2-08 

26-8 

34-8 

41-5 

92-9 

35-1 

131 

65-7 

•0606 

376 

a 

•5 

2-59 

33-5 

38-8 

46-4 

104 

39-3 

147 

73-4 

•0757 

460 

.^ 

•6 

311 

40-2 

42-4 

50-9 

114 

43-0 

161 

80-5 

•0909 

544 

a 

•7 

3-63 

46-9 

45-8 

54-9 

123 

46-4 

175 

86-9 

•106 

627 

3 

•8 

4-05 

53-6 

48-3 

58-6 

134 

49-7 

186 

92-9 

•121 

711 

a 
1— ( 

•9 

4-67 

60-3 

51-8 

63-5 

139 

52-7 

197 

98-5 

•136 

795' 

1 

1 

519 

67 

54-5 

65-6 

147 

55-5 

208 

104 

•152 

879 

1 

2 

10-4 

134 

76-6 

92-9 

208 

78-7 

290 

147 

•302 

1720 

3 

15^6 

201 

93-4 

113-8 

254 

96-2 

360 

180 

•454 

2550 

4 

20-8 

268 

109 

131-4 

294 

111 

415 

208 

•606 

3350 

5 

25-9 

335 

120 

147 

328 

124 

464 

232 

•757 

4230 

6 

31^1 

402 

131 

165 

361 

136 

509 

254 

•909 

5070 

7 

36-3 

469 

142 

175 

389 

147 

551 

275 

1-06 

5900 

8 

40-5 

536 

150 

185 

415 

157 

587 

294 

1-21 

6700 

9 

46-7 

603 

160 

190 

441 

166 

623 

312 

1-36 

7600 

10 

51^9 

670 

169 

208 

464 

175 

656 

328 

1-52 

8400 

'  Neglecting  work  wasted  in  the  engine  itself.     -  External  air  assumed  to  be  at  41°  F. 
'  Beyond  this  point  the  numbers  have  no  practical  value  for  a  40-foot  shaft. 


WABMING  AND    VENTILATION  85 

air  per  second  through  a  shaft  of  known  height  in  which  a  given  quantity  of 
gas  is  burning. 

Having  now  given  an  account  of  the  various  means  by  Avhich  a  head  can 
be  produced,  we  give  on  the  preceding  page  a  comparative  table  of  the  nume- 
rical results  produced  by  the  different  agents.  "We  shall  so  frequently  employ 
both  *  foot-pounds  per  pound '  and  equivalent  water-pressure  to  express  the 
head  that  we  have  thought  well  to  include  in  the  preceding  table  the  numerical 
expression  of  head  in  both  manners,  assuming  that  the  air  delivered  is 
half  saturated  and  at  50°  F.  and  30  inches  of  mercury. 

Local  Cieculation 

29.  We  have  now  completed  our  discussion  of  the  general  circulation  of  air 
in  a  ventilation  system,  and  have  confined  our  attention  to  the  motion  in  the 
■ducts,  where  the  general  direction  of  the  motion  across  the  whole  section  of 
the  duct  is  along  the  sides  ;  we  have  now  to  consider  the  motion  of  the  air  in 
the  space  which  the  ducts  are  intended  to  ventilate.  In  that  space  the  air 
which  enters  by  the  inlets  makes  its  way  by  a  more  or  less  devious  course  to 
the  outlets  ;  if  our  knowledge  were  complete  we  ought  to  be  able  to  predict 
the  exact  path  which  the  air  would  take  through  the  room  from  the  inlet  to  the 
outlet,  although  it  might  be  extremely  involved  and  complicated ;  but,  as  we 
have  already  said,  in  all  ordinary  cases  the  air  of  a  room  is  thrown  by  local 
sources  of  heat  and  other  causes  of  motion  into  a  state  of  really  inde- 
scribable turmoil,  and  taken  in  detail  the  motion  is  unsteady  and  incalculable. 
All  that  we  can  do  by  way  of  calculation  is  to  lay  down  some  general  principles 
which  govern  the  circulation  of  air  in  the  ventilated  space,  or  local  circulation, 
as  we  have  called  it.  Experimentally  we  can  do  on  a  small  scale  what  is 
habitually  done  on  a  large  scale  by  meteorologists,  and  determine  at  any 
instant  the  direction  and  force  of  the  wind  at  any  particular  point  of  the 
room,  and,  just  as  they  do,  we  can  lay  down  upon  a  chart  an  arrow  which,  by 
the  way  it  points,  shows  the  direction  of  motion  of  the  air,  and,  by  some 
convention  as  to  the  character  of  the  arrows,  indicate  the  force.  But  here 
we  meet  with  a  considerable  difficulty  both  in  the  matter  of  experimental 
:determination  and  of  diagrammatic  representation  too.  Meteorologists,  as  a 
.rule,  deal  only  with  the  horizontal  motion  and  effect  of  wind,  whereas  with 
Tis  the  vertical  motion  is  at  least  as  important  as  the  horizontal,  so  that  we 
ought  to  be  able  to  set  our  arrow  in  any  direction  whatever,  and  we  really 
want  a  solid  model  for  the  purposes  of  representation. 

"We  must,  however,  be  content  with  a  very  incomplete  and  partial  inves- 
tigation of  the  local  circulation,  and  represent  the  motion  in  horizontal  or 
vertical  sections.  It  will  be  seen  that  if  we  could  have  a  sufficient  number 
of  direction -arrows  arranged,  the  one  to  follow  the  other,  we  should  be  able 
to  start  from  the  outlet  and  ultimately  arrive  at  the  inlet,  and,  assuming 
that  the  motion  in  any  particular  part  of  the  room  has  remained  the  same 
throughout  the  course  of  the  investigation,  we  should  be  able  to  construct 
a  curved  line  from  the  inlet  to  the  outlet,  which  would  indicate  the  direction 
■of  motion  of  the  air  at  any  point  of  its  length.  Such  a  line  would  be  called 
,a  '  stream-line,'  and  a  complete  set  of  stream-lines  would  give  a  complete 
account  of  the  motion  of  the  air  from  inlets  to  outlets,  provided  that  the 
motion  were  steady.  At  the  inlet  itself  the  stream-lines  would  evidently 
join  on  to  the  lines  of  flow  of  the  air  in  the  duct. 

But  when  an  air  current  enters  a  room  there  is  a  gradual  interchange  of 
individual  particles  between  the  air  in  the  stream  and  the  adjacent  air  :  this 
results  in  an  obliteration  of  the  stream-lines  near  the  boundary.     The  effect 


86 


HYGIENE 


is  considerably  increased  by  the  friction  between  the  moving  air  and  the 
neighbouring  air,  which  gives  rise  to  a  series  of  eddies,  so  that  the  motion  of 
the  air  often  camiot  be  traced  as  a  continuous  stream  for  any  great  distance 
from  the  inlet.  Stream-lines  are  still  further  obliterated  by  the  cross  currents, 
due  to  local  causes,  such  as  the  convection  produced  by  sources  of  heat  in 
the  room.  These,  as  we  have  said  (§  14),  are  often  very  numerous,  and 
often  varyingj  and  hence  we  cannot  hope  to  trace  the  complete  path  of  the 
entering  air.  There  are,  however,  some  cases  in  which  the  conditions  are 
favourable  to  the  permanence  of  the  currents,  over  a  comparatively  long 
path,  and  steady  motion,  with  stream-lines  of  permanent  shape,  establishes 
itself  in  certain  parts  of  the  room.  For  such  cases,  if  the  air  of  the  currents 
is  cold,  and  passes  across  the  occupants  of  a  room,  the  effect  is  well  knoA\ai 
as  a  draught.  A  good,  steady  draught  is  a  sufficient  indication  of  steady 
stream-lines  of  cold  air  in  tlie  region. 

30.  Well-established  stream-lines  of  hot  air  are  also  frequently  formed  in 
vertical  columns  and  across  ceilings,  but  as  they  are  generally  out  of  the 
reach  of  persons  occupying  the  rooms,  or  are  not  so  markedly  unpleasant  as 
cold  currents,  they  are  less  generally  noticed. 


^  Fllt  pe:r  Mrw: 
"9 


132" 


Pig.  22, 


_M3  TE'ET   PER  MMUTt 


fEET 


Fig.  23 


Stream-lines  can,  moreover,  generally  be  traced  in  the  immediate  neigh- 
bourhood of  inlets  and  outlets.  In  speaking  of  air-ducts  we  have  given  the 
name  of  rapids  to  that  part  of  the  jet,  either  issuing  or  emergent,  where  the 
motion  is  very  considerable.  We  can,  therefore,  trace  the  stream-lines  for 
the  rapids,  and  the  main  use  of  this  tracing  will  be  to  indicate  the  limits  of 
the  rapids. 

In  order  that  the  reader  may  form  for  himself  an  accurate  idea  of  the 
extent  of  the  rapids  formed  by  a  current  of  air  issuing  mto  a  room  as  it 
spreads  out  from  the  orifice  under  the  influence  merely  of  its  own  motion, 
we  have  made  two  diagrams  drawn  to  scale  (figs.  22,  23),  from  measurements 
upon  actual  currents  generated  by  a  '  Cyclops  '  rotary  fan  in  a  large  room, 
showing  the  boundary  line  on  each  side  of  a  horizontal  section  of  the  current 
and  the  velocity  of  air  at  the  core.  The  currents  were  delivered  through  a 
short  straight  cardboard  tube  about  fourteen  niches  long.  It  will  be  noticed 
that  the  current  with  the  higher  velocity  has  a  wider  angle  of  spread  at  the 
nozzle,  and  the  velocity  m  the  core  falls  off  more  rapidly  in  the  stronger  than 
with  the  slower  running  current.     The  general  shape  of  the  stream-lmes  in 


WARMING  AND   VENTILATION 


87 


the  rapids  can  easily  be  inferred  from  the  direction  of  motion  at  the  orifice 
and  the  extent  of  the  rapids. 

The  energy  of  the  motion  of  the  issuing  air  is  more  dissipated  in  eddies 


SCALE /9 

Fig.  24. 

if  the  velocity  of  entry  be  greater,  as  the  diagrams  indicate,  thus  a  rapid 
current  of  air  will  cause  more  complete  mixing  with  the  air  in  the  room  than 
the  slow  delivery  of  the  same  quantity  of  air  through  a  larger  opening  ;  but, 


Fig.  25. 

on  the  other  hand,  the  greater  velocity  means  a  much  more  definite  current 
for  a  short  distance,  and  hence  may  cause  unendurable  draughts,  whereas 
the  slow  delivery  may  cause  more  widely  extended  draughts,  which  though 
unpleasant  are  not  classed  as  unendurable. 

We  have  reproduced,  also,  three  diagrams  of  inlets  (figs.  24,  25,  and  26), 


88 


HYGIENE 


and  one  of  an  outlet  (fig.  27),  by  General  Morin  (Etudes,  ii.  pp.  184-188), 
representing,  in  vertical  section,  the  extent  of  the  rapids  for  two  orifices  of 
entry,  and  one  orifice  of  exit  respectively.  In  figs.  21  and  27  the  orifice 
represented  is  the  same,  a  rectangular  opening  eleven  feet  by  three  inches. 
The  velocity  of  entry  in  fig.  24  is  about  six  feet  per  second,  and  in  fig.  27 
the  velocity  of  exit  about  7*5  feet  per  second.  The  observed  dimensions  of 
the  stream  are  figured  on  the  dra\Yings  in  millimetres.  The  dotted  line  of 
boundary  of  fig.  24  shows  the  observed  extent  of  the  vertical  section  of  the 
entering  stream,  within  which  the  velocity  is  sufficiently  great  to  affect  an 
air-meter,  that  is,  not  less  than  5'5  inches  per  second.  The  full  line  indicates 
the  same  boundary  with  the  irregularities  of  observation  smoothed  out.     The 


SC/lLt  1^s 
Fig.  26. 


SCALE /9 
Fig.  27. 


boundary  Hne  in  fig.  27  similarly  indicates  the  limit  beyond  which  the  air- 
meter  ceases  to  show  a  current. 

Figs.  25  and  26  represent  vertical  sections  of  streams  of  air  issuing  from 
a  rectangular  opening  four  feet  wide  by  three  inches  high.  The  boundaries 
of  the  stream  were  determined  by  the  use  of  a  candle  flame.  Fig.  25  repre- 
sents two  streams,  the  wider  issuing  at  the  rate  of  3'3  feet  per  second,  the 
narrower  at  two  feet  per  second.  The  dimensions  of  the  former  are  figured 
on  the  drawing  in  millimetres.  Fig.  26  represents  the  vertical  section  of  a 
stream  issuing  from  the  same  orifice  as  the  preceding  at  the  rate  of  2*4  feet 
per  second.  The  issuing  air  in  all  these  cases  was  cold.  Compared  with 
the  streams  represented  in  figs.  22  and  23,  the  widening  out  at  a  short  dis- 


WABMING  AND   VENTILATION 


89 


tanee  from  the  orifice  is  very  marked,  and  is  to  be  attributed  to  the  orifice 
being  long  and  narrow  instead  of  being  cyhndrical. 

31.  We  shall  attempt  to  give  in  figs.  28, 29,  and  30  some  actual  examples 
of  stream-lines  drawn,  or  rather  inferred,  from  observations  of  the  vertical 
motion  of  air,  so  as  to  give  the  reader  a  general  idea  of  what  the  motion  of 
air  would  be  in  any  special  case  of  ventilation  that  he  may  have  to  deal 
with.  In  general  character,  the  problem  is  the  same  as  the  determination 
of  the  flow  of  water  in  corresponding  cases ;  and  the  reader  may,  perhaps, 
be  helped  to  reahse  the  actual  state  of  the  motion  of  the  air  in  any  special 
case  if  he  will  consider  what  the  distribution  of  currents  would  be  if  water 
were  the  fluid  he  were  dealing  with  instead  of  air.  The  permanence  of  slow 
currents  of  water  through  water  can  be  shown  experimentally  if  the  flowing 
water  be  slightly  coloured,  and  there  is  little  doubt  that  analogous  cases  of 
the  flow  of  air  through  air  could  be  exhibited  if  the  flowing  air  could  be  as 
easily  identified  as  coloured  water.  An  obstacle  in  the  way  of  a  current  of 
air  promotes  the  formation  of  eddies  and  consequent  mixing,  especially  if 
the  flow  is  rapid  ;  if  the  flow  is  slow,  however,  a  steady  current  may  establish 
itself  round  the  obstacle. 

In  order  that  the  effects  of  the  flow  may  be  freed  from  disturbance  on 
account  of  its  difi"erent  density  the  entering  air  must  be  at  the  same  tem- 
perature as  that  into  which 
it  flows.  This  is,  however, 
seldom  practicable,  and  we 
must  deal  with  cases  of 
flow  into  relatively  warmer 
or  colder  air.  In  such 
cases  a  horizontal  current 
will  be  deflected  down- 
wards or  upwards,  as  the 
case  may  be.  A  current 
of  warm  air  directed  ver- 
tically upward  will  extend 
further,  and  a  correspond- 
ing current  of  cold  air  will 
be  less  extensive,  and,  vice 
versa,  when  the  direction 
of  the  current  is  vertically 
downward.  An  orifice  for 
the  admission  of  cold  air 
in  the  ceiling  of  a  room 
shghtly  warmer  than  the 
entering  air  affords  a  very  good  instance  of  permanent  stream-hnes  continuing 
to  the  table  or  floor  underneath  the  opening.  In  a  large  hall  or  church,  a 
lantern  tower  with  large  area  of  windows  may  produce  near  the  floor  below 
it,  on  a  cold  day,  a  descending  current  which  very  clearly  exemplifies  the 
steadiness  of  flow  for  a  considerable  vertical  distance  ;  the  effect  produced  on 
those  sitting  below  is  that  of  a  cold  down-draught,  not  attributable  to  open 
windows,  but  to  the  cooling  effect  of  the  windows  on  the  air  of  the  tower. 
A  similar  effect  may  frequently  be  observed  at  the  sides  of  churches  with 
clerestory  windows.  A  row  of  hot-water  pipes  along  the  central  passage  of 
the  church  produces  an  oppositely  directed  current  of  warm  air  ;  the  circu- 
lation is  completed  by  a  cold  air  current  along  the  floor  and  an  opposite 
current  along  the  ceiling.  The  course  of  the  currents  is  represented  by  arrows 
in  fig.  28.     The  result  of  such  an  arrangement  will  therefore  be  that  a  larse 


Fig.  28. 


90 


HYGIENE 


pai-t  of  the  beat  of  the  pipes  will  pass  through  the  glass  of  the  windows  with- 
out producing  any  effect  in  raising  the  general  temperature  of  the  building. 

In  the  case  figured  the  currents  are  not  due  to  the  introduction  of  fresh 
air  from  outside,  but  to  the  circulation  established  in  the  interior  of  the 
building.  In  introducing  fresh  cold  air  it  is  extremely  difficult,  if  not 
impossible,  to  prevent  cold  currents  in  the  lower  parts  of  the  building. 
With  the  object  of  avoiding  such  currents  the  incoming  fresh  air  is  directed 
upwards  either  by  a  Tobin  tube  (see  fig.  29)  or  a  JSherringham  inlet,  or,  more 
simply,  by  leaving  an  open  space  between  the  upper  and  lower  sashes  of  the 
windows ;  but  if  these  expedients  be  primarily  successful  in  mixing  the 
incoming  fresh  air  with   some  of  the  warmer  air  of  the  room  we  still  get  a 


64° 


f  ^ 

/'r      ^' 

t 

/       <r^ 

,'            r 

-  t 

\  54° 

>.^ 

\\ 

o 

36-5 

\    ^^.^ 

A 

— j    55°   '^ 

;     \ 

s 

'  I 

S-- 

/? 


59° 


SCALE  XoTLtolfaot 

Fig.  29. 


SCALL  %C7lM)1pOt' 
Fig.  30. 


reservoir  of  air  near  the  ceiling  (round  the  opening)  considerably  colder  than 
the  air  of  the  rest  of  the  room,  and  the  next  stage  of  the  problem  may  be 
stated  thus  :  Certain  outlets  have  to  be  supplied  and  the  air  has  to  be  moved 
from  the  cold  regions  (near  the  inlets)  to  the  outlets  ;  what  will  be  the  dis- 
tribution on  the  floor  ?  The  best  answer  that  can  be  given  is  that  the 
colder  air  will  make  a  very  short  journey  to  the  floor,  and  will  then  move 
along  the  floor  towards  the  outlets  if  they  are  near  the  floor  ;  if,  however, 
they  are  near  the  ceiling,  a  layer  of  cold  air  will  lie  on  the  floor  until  part 
of  it  is  warmed  sufficiently  to  rise  to  the  outlets. 

Warm  air  delivered  into  a  room  will  behave  in  just  the  opposite  way  : 
if  it  is  directed  upwards  it  will  make  its  way  direct  to  the  ceiling  ;  if  directed 


WABMING  AND   VENTILATION  91 

downwards,  the  flow  in  that  direction  will  soon  be  stopped,  and  a  reservoir 
of  air  formed,  warmer  than  the  rest,  and  from  this  warm  reservoir  air  will 
rise  to  the  ceiling  and  there  form  a  warm  layer. 

In  order  to  illustrate  the  motion  of  the  air  in  these  two  typical  cases 
I  have  investigated  experimentally,  by  apparatus  described  in  a  subsequent 
chapter,  the  flow  of  air  from  two  Tobin  tubes,  one  delivering  cold  air  and  the 
other  warm  air,  and  plotted  the  distribution  of  flow  for  the  two  cases  in 
figs.  29  and  30.  The  figures  are,  of  course,  only  rough  approximations,  but 
they  are  drawn  to  scale  so  as  to  give  an  idea  as  to  how  far  the  motion 
extends  in  the  two  cases.  The  boundary  of  the  stream  of  air  is  represented 
by  a  dotted  line,  and  the  direction  of  flow  by  arrows  ;  the  velocity  in  the 
tube  is  indicated,  as  well  as  the  temperatures  in  the  tube,  the  stream,  and 
the  air  of  the  room. 


APPLICATION   OP  THE   FOREGOING  PEINCIPLES   TO   SPECIAL   CASES 

32.  In  discussing  the  principles  of  ventilation  we  have  analysed  the  process 
into  '  General  Circiilation  '  (§§  15-28),  and  '  Local  Circulation '  (§§  29-31), 
and  have  considered  separately  the  effect  of  different  characteristic  conditions. 
The  application  of  the  principles  will  be  made  clearer  if  we  take  some 
specific  instances.     We  will  arrange  them  in  order  of  simplicity. 

1.  Closed  Room  with  Heating  Apparatus 

33.  Let  us  first  suppose  that  we  have  a  room  which,  during  its  occupation, 
has  no  opening  except  unintentional  crevices,  and  which  is  warmed  by  a  gas 
stove  without  chimney,  or  by  hot- water  pipes  along  the  floor  on  one  side. 
It  is  provided  with  windows  which  we  suppose  to  be  shut.  From  the  point 
of  view  of  ventilation  such  a  room,  of  course,  borders  on  the  impossible,  but 
there  can  be  few  people  who  have  not  had  to  spend  some  hours,  at  any  rate, 
in  rooms  of  which  the  above  is  a  fairly  accurate  description. 

Here  we  have  to  deal  with  local  circulation  only.  General  circulation  does 
not  exist  to  any  large  extent ;  enough  fresh  air  comes  in  at  some  of  the 
crevices,  supplying  the  place  of  air  that  leaves  by  the  others,  to  keep  a  gas 
fire  burning  continuously.  If  it  is  cold  the  fresh  air  forms  a  layer  on  the 
floor  and  devotes  itself  almost  exclusively  to  the  combustion  of  the  gas. 
The  local  circulation  is  fairly  simple  ;  the  stove  or  hot-water  pipes  cause  an 
upward  current,  the  window  a  downward  current,  and  so  there  exists  a 
fairly  active  circulation  between  the  stove,  or  water-pipes,  and  the  windows. 
The  persons  in  the  room  also  cause  upward  currents,  so  that  the  air  is  kept 
fairly  well  mixed.  Here  our  description  of  the  circulation  ceases  ;  the 
length  of  time  that  such  a  room  is  endurable  depends  first  upon  its  size  and 
secondly  upon  the  powers  of  endurance  of  the  individuals.  The  gas  stove  is 
an  aggravation  of  the  defect ;  the  hot-water  pipes,  especially  in  a  large  hall, 
help  to  keep  the  room  habitable  somewhat  longer  than  if  they  were  not 
present  by  promoting  the  local  circulation. 

2.  EooM  WITH  Single  Opening 

34.  The  unsatisfactory  character  of  the  air  of  the  preceding  example  leads 
us  naturally  to  the  second,  which  we  may  represent  by  a  room  with  an  open 
window.  It  will  materially  aid  the  correct  appreciation  of  this  case  if  we 
consider  the  liquid  analogue  of  it.     Imagine  a  glass  box  filled  with  oil  and 


92 


HYGIENE 


immersed  in  a  large  tank  of  water,  and  imagine  further  an  opening  to  be 
made  in  the  side  of  the  box  of  oil.  The  oil  being  lighter  than  the  surrounding 
water,  the  water  would  flow  in  at  the  lower  part  of  the  opening  and  drive 
the  oil  out  at  the  upper  part  of  it ;  after  passing  into  the  box  the  water 
would  settle  down  to  the  bottom  and  form  a  layer  there.  The  replacement 
of  oil  by  water  would  go  on  until  the  part  of  the  box  below  the  level  of  the 
top  of  the  opening  was  filled  with  water  ;  then  the  circulation  would  cease. 

The  oil  cannot  mix  with  water,  so  that  the  analogy  is  not  quite  strict.  A 
more  accurate  representation  would  be  secured  by  using  water  in  a  solution 
of  salt,  but  in  this  case,  as  in  the  case  of  hot  and  cold  air,  the  mixing  which 
takes  place  between  the  inflowing  air  and  the  surrounding  air  is  not  suf- 
ficiently extensive  to  destroy  the  analogy. 

In  a  room  with  a  single  vertical  aperture  on  one  side  we  have,  there- 
fore, a  '  general  circulation,'  air  entering  by  the  lower  part  of  the  aperture 
and  issuing  by  the  upper  part.     The  '  local  circulation  '  depends  very  largely 


li 


t 


Fig.  31. 

upon  the  position  of  the  water  pipes,  but  if  they  are  at  some  considerable 
distance  from  the  positions  vertically  under  the  opening,  a  cold  shower  of 
air  and  a  cold  current  along  the  floor  are  inevitable,  together  with  a  warm 
ascending  current  from  the  hot  pipes,  ultimately  reaching  to  the  opening. 
The  action  of  the  wind  in  this  case  affects  the  velocity  of  ingress,  and 
therefore  the  position  at  which  the  cold  air  shower  is  most  keenly  felt.  The 
common  outcry  in  such  a  case  for  having  the  windows  opened  '  on  the  other 
side  of  the  room  '  is  merely  emlence  of  the  intensity  of  the  cold  shower, 
which  is  really  unavoidable  by  any  such  expedient.  If  the  hot  pipes  are 
immediately  under  the  windows  the  state  of  affairs  may  be  improved  by  the 
mixing  of  currents  ;  but  cold  air  is  very  persistent  in  finding  the  floor  level. 

The  calculation  of  the  effect  of  a  single  opening,  as  that  described,  can  be 
arrived  at  by  considering  the  course  of  the  air  from  its  entry  to  its  exit,  and 
regarding  the  part  in  motion  as  separated  from  that,  comparatively  speaking, 
at  rest  by  imaginary  partitions. 

We  may  roughly  indicate  the  boundary  of  the  flow  by  the  dotted  line  in 
fig.  31,  A  B  being  the  orifice,  and  S  the  point  of  division  into  inlet  and  outlet. 
If  the  line  X  Y  be  a  line  dividing  the  upcast  part  from  the  downcast,  X  Y  may 
be  treated  as  the  section  of  a  chimney  flue  for  which  S  B  is  the  inlet  orifice, 
and  A  S  the  outlet  orifice  ;  the  head  will  be  due  to  the  difference  of  density  of 


or 


WABMING  AND   VENTILATION  93 

the  air  in  the  portion  S  B  to  X  Y,  and  the  portion  X  Y  to  A  S  respectively  ;  if 
we  can  assume  the  air  of  these  two  portions  to  have  mean  temperature  t  and 

T  respectively,  the  head  lb  (p.  82)  will  be  roughly   —  -  (T  —  t)  H,  where  H 

is  the  height  of  the  window  opening  above  the  floor.     The  resistance  to  the 

flow  will  arise  from  the  window-opening  merely  ;  at  other  parts  of  the  flow  the 

resistance  will  be  very  small.     Suppose  A  to  be  the  area  of  the  opening  and 

A 
that  the  inflow  area  and  outflow  areas  are  equal,  each  being  equal  to    — . 

Then  taking  these  areas  as  being  thin  plate  orifices  the  resistance  of  each  will 

^e   E  =  27AV4=-7A2  approximately. 

The  total  resistance  will  therefore  be  -— p^, 

7A^ 

and  the  flow  will  be 

/lb  =      /(T-^)     h^Tta^ 
V  E        V     500     *         2 

=A^  /  (-*-  ~t)ii-  cubic  feet  per  second, 
V       140 

/(i     t)  ti   QTj^\yiQ  fggi;  pgj,  square  foot  of  opening. 

Example. — The  temperature  of  a  roomis  70°  F.,  the  external  temperature 
20°  F.  ;  a  window  14  feet  above  the  floor  is  opened  so  as  to  give  an  aperture 
Sft.  6  in.  wide  x  2ft.  high  :  find  the  amount  of  air  that  will  flow  in  per  second. 

We  shall  here  assume  the  temperature  of  the  upcast  to  be  70°  and  that 
of  the  downcast  20°.  Such  a  distribution  is  only  a  rough  approximation  to 
the  actual  state  of  things  after  the  window  has  been  opened  some  time. 

By  the  above  calculation  the  flow  is 

7  X  A  /        ^       =  15'6  cubic  feet  per  second. 
V       140 

The  velocity  at  entry  will  be  about  five  feet  per  second,  and  elsewhere  it 
will  be  inversely  proportional  to  the  section  of  the  moving  stream. 

35.  When  the  aperture  is  in  the  ceiling  instead  of  the  side  the  problem  is 
very  similar,  but  there  being  no  top  or  bottom  division  of  such  an  aperture, 
an  interesting  modification  is  produced  that  may  also  be  illustrated  by  the 
liquid  analogue.  A  heavy  fluid  on  the  top  of  a  light  one,  as  when  a  bottle 
of  water  without  a  cork  is  immersed  in  a  larger  vessel  of  salt  solution,  or,  to 
take  a  commoner  example,  when  a  bottle  of  water  is  inverted,  and  the  cork 
withdrawn,  is  really  in  unstable  equilibrium ;  and,  as  a  rule,  the  fluids  of 
different  densities  begin  to  change  places.  But  the  character  of  the  motion 
is  different  according  to  the  size  of  the  orifice  ;  if  this  be  large  the  hghter 
fluid  runs  up  one  side,  and  the  heavier  down  the  other  ;  if  it  is  very  small 
indeed  no  flow  takes  place  at  all ;  for  apertures  of  intermediate  size  we  get 
the  intermittent  flow  that  is  a  familiar  phenomenon  observed  whenever  a 
bottle  of  water  with  a  narrow  neck  is  inverted.  This  interesting  case 
arises  because  the  two  fluids  cannot  divide  the  channel  between  them. 
Similar  phenomena  are  exhibited  with  air.  If  a  candle  is  burned  in  a  bell- 
jar,  the  only  aperture  of  which  is  a  long  narrow  tube,  the  air  which  comes 
out  in  consequence  of  the  expansion  by  heat  prevents  the  outside  air  from 
entering,  although  it  is  heavier  than  the  internal  air  beneath  it,  and  the 
candle  ultimately  becomes  extinguished  for  want  of  oxygen.  If,  however, 
the  aperture  is  sufficiently  wide  a  circulation  results,  and  between  these 


94  HYGIENE 

limits  we  have  the  intermittent  draught  and  back  draught  that  a  wide 
chimney  exhibits  when  there  is  not  a  sufficient  supply  of  air  inlets  in  the 
room.  If,  however,  the  aperture  be  divided  into  two  parallel  parts  by  a 
vertical  partition,  when  once  the  cold  air  has  gone  down  one  side  and  the 
warm  air  up  the  other  the  flow  is  stable  and  continuous.^ 

The  local  circulation  for  a  double  aperture  in  the  ceiling  acting  as  inlet 
and  outlet  is  not  sufficiently  dissimilar  from  that  of  an  aperture  in  the  side 
for  us  to  devote  more  space  to  it. 

The  efl'ect  of  such  an  arrangement  can  be  calculated  in  a  manner  very 
similar  to  the  case  of  the  aperture  in  the  side.  Taldng  the  mean  tempera- 
ture of  the  whole  height  H  of  the  downcast  (which  must  be  measured  from 
the  outside  of  the  ventilator  to  the  floor  of  the  room)  as  being  t,  and  the 
mean  temperature  of  the  whole  upcast  as  T,  we  have  the  head 

The  resistance  R  would  be  due  solely  to  the  channel  through  the  ceiling, 
and  can  be  calculated  by  the  rules  of  §  20  ;  from  these  two  the  flow  can  be 

determined. 

Example. — A  room,  the  temperature  of  the  air  of  which  is  70°  F.,  is 
jjrovicled  with  a  vertical  ventilating  shaft  from  the  ceiling  to  the  external  air. 
The  length  of  the  shaft  is  5  feet,  and  it  is  divided  by  a  partition  into  tioo 
parallel  tubes,  the  area  of  each  of  which  is  1  foot  x  finches  ;  find  the  floio 
through  the  shafts  if  the  external  temperature  be  20°  F.  The  height  of  the 
room  is  15  feet. 

Taldng  the  temperature  of  the  whole  downcast  at  20°  F. ,  and  of  the  whole 
upcast  at  70°  F.,  the  height  from  floor  to  top  of  ventilator  being  20  feet,  we 
have,  as  m  the  previous  example,  the  head 

113= J-   X  50  X  20  =  2  feet  of  air. 
'•^     500 

In  order  to  calculate  the  resistance,  we  may  consider  each  comparatively 
short  wide  tube  as  a  cylindrical  mouthpiece,  which  has  a  coefficient  of  con- 
traction -8.     The  resistance  of  each  will  therefore  be  (§  20  {a)  and  {h)) : 


B 


=  JL  X  .    /^  ,^  =  -0431. 
64-4       -64  X  9 

The  resistance  of  the  whole  circulation  will  therefore  be  -086  ;  from  which 

we  eet  the  flow  =   .  /_^,  or  about  5  cubic  feet  per  second.    The  velocity 

^  V  -086 

of  influx  is  about  6  feet  per  second. 


3.  Room  with  two  Sepakatb  Openings 

36.  The  next  stage  in  the  development  of  a  complete  ventilation  system 
is  a  room  with  two  separate  openings,  one  of  which  acts  as  an  exit  flue  and 
the  other  as  an  inlet.  This  is  the  typical  case  referred  to  above  (p.  62),  and 
we  need  not  consider  further  the  general  theory  of  the  circulation.      It  is, 

1  This  principle  is  exemplified  in  Watson's  ventilator  and  Muir's  ventilator. 


WABMING  AND   VENTILATION  95 

however,  a  case  of  such  very  frequent  occurrence,  every  room  witli  an  open 
iire  and  no  special  mlet  being  substantially  an  example  of  it,  that  we  are 
led  by  its  importance  to  consider  some  of  the  details.  Let  us  consider  first 
of  all  the  case  of  a  room  with  an  open  fireplace,  and  an  inlet  whose  equivalent 
orifice  is  i  ;  let  the  equivalent  orifice  of  the  chimney  be  o  ;  then  if  lb  be  the 
head  in  feet  of  air,  we  have  the  flow 


"^  —        /^j '^-r—  =        /  z. -^~  cubic  feet  per  second. 

Let  us  first  examine  the  effect  upon  the  flow  of  a  change  of  size  of  the 
inlet  orifice.  It  is  evident  that  the  maximum  value  of  the  flow  whicli  is 
attained  when  i  is  extremely  large,  as,  for  instance,  when  the  room  v/indows 
are  wide  open,  is  ^^  27  If)  o^,  and  if  the  inlet  be  narrowed  the  flow  will  be 
gradually  decreased  until  it  ceases  altogether,  when  there  is  no  inlet  orifice,  i.e. 
when  i  is  zero.  Now  we  have  already  seen  that  a  single  flue  may  act  as  inlet 
and  outlet  simultaneously,  the  cold  air  coming  down  one  side  and  the  hot 
going  up  the  other.  Hence  as  the  inlet  orifice  is  gradually  narrowed  we 
approach  this  condition.  If  the  inlet  orifice  be  not  actually  zero,  but  only 
very  small,  there  may  still  be  a  tendency  for  this  double  action  of  the  flue  to 
establish  itself,  in  which  case  the  chimney  will  '  smoke,'  a  phenomenon 
sometimes  experienced  with  chimneys  with  straight  flues,  when  the  access  of 
air  to  the  room  is  not  sufficient.  Let  us  extend  the  reasoning  further,  and 
inquire  into  the  conditions  under  which  this  kind  of  '  smoking  '  is  likely  to 
take  place.  We  suppose  a  small  inlet,  say  the  crevices  of  doors  and  windows, 
with  an  equivalent  orifice  i  ;  then  there  are  two  alternatives  which  the  air  may 
choose  in  order  to  replace  the  lighter  warm  air  by  the  heavier  cold  air  :  (1)  the 
chimney  behaves  as  an  outlet  only,  the  whole  air  supply  coming  through 
the  crevices  ;  the  flow  in  this  case  is 


^27  lb. 

(2)  the  chimney  acts  as  both  inlet  and  outlet,  air  coming  also  through  the 
chinks.  In  the  second  case,  if  Ave  suppose  half  the  shaft  to  be  occupied  with 
cold  air  coming  down  and  the  other  half  with  warm  air,  the  air  coming  down 
the  shaft  may  be  regarded  as  traversing  a  tube  of  half  the  area  of  the 
chimney :  the  equivalent  orifice  of  entry  for  this  duct  will  be  o/2,   and,  by 

law  4  (p.  64),  the  whole  orifice  of  inflow  will  be  i  +  ^,  and  the  inlet  resist- 
ance 1 


(^+1)- 


27 


the  outlet  resistance,  that  of  the  other  half  of  the  shaft, 

the  total  resistance  will  therefore  be 

1  1 

+ 


27fi+|y       27  Q) 


06  HYGIENE 

The  head  may  be  assumed  to  be  the  same  in  both  cases,  and  hence  the  flow 
on  the  second  alternative  will  be 


Xow  we  have  to  decide  which  of  these  two  alternatives  the  air  will  choose. 
"We  may  assume  that  that  alternative  will  be  chosen  which  offers  the  least 
resistance,  and  this  will  be  the  second  one  if 

1  ._J_  1        1 

'''    '  —  2    is  less  than  _  -|-  - . 


(^-ir  G) 


I'  0' 


It  can  be  shown  that  the  condition  is  that  i  should  be  less  than  o/2. 
Hence  we  find  that  the  chimney  will  '  smoke  '  if  the  total  area  of  the  inlet 
orifice  is  less  than  half  the  equivalent  orifice  of  the  chimney.  This  result 
is  of  considerable  interest,  but  it  cannot  be  pressed  with  great  numerical 
accuracy  on  account  of  the  numerous  assumptions  made  in  the  course  of  the 
reasoning  ;  but  it  is  sufficient  to  show  in  a  striking  manner  the  importance 
of  providing  sufficient  inlet  area.  Further,  it  may  explain  a  well-known 
empuical  principle  advocated  by  some  architects,  namely,  that  to  prevent 
smoking,  a  chimney  should  not  be  straight  but  bent.  It  is  easy  to  see  that 
at  the  bends  the  up  and  down  currents  would  mix,  and  the  division  of  the 
shaft  between  the  two  could  hardly  under  any  circumstances  be  established, 
and,  therefore,  this  particular  cause  of  smoking  could  not  be  active  in  a 
chimney  with  a  bent  shaft. 

In  the  equations  we  have  used  hitherto  we  have  neglected  the  change  in 
the  density  of  air  when  it  is  heated  ;  we  have,  in  fact,  assumed  the  flow  in 
cubic  feet  per  second  to  be  the  same  at  the  inlet  and  the  outlet.  If,  however, 
the  difference  of  density  is  too  great  to  be  neglected,  we  may  correct  the 
equations  as  follows.  Dividing  the  total  head  into  partial  heads  h^  and  /i^ ,  we 
have  for  the  flow  V  through  the  outlet  in  cubic  feet  per  second 

h 
1 


27o2 

and  for  the  flow  through  the  inlet,  V^  =  .2,  ^ 

27T2 

But  if  A  is  the  density  of  the  cold  air,  and  A'  that  of  the  warm  air,  V^A^ 

__  Y'2_\/2^ 

"  «J      M  27i2       27o2      A'2 

=Y^\Jl.  4.    1_    {l  +  a(T-32)]2 
1  27^2  "^  27o2    {1  +  a(iJ- 32)2) 

where  T  is  the  temperature  of  the  air  in  the  shaft,  t  the  external  temperature, 
and  a  the  coefficient  of  expansion  of  air,  i.e.  1/491. 

Hence  1b  -^M  ^  +  U  +  «  (T  -  32))2) 

Hence  113  -  ^^  1^^+ ^^  (1  +  a(«- 32)}2r 


WABMING  AND   VENTILATION  97 

and  1I3  =  ^^J_-   (T-OH       .         .         .         (§28.) 

This  somewhat  complicated  calculation  can  easily  be  pursued,  by  those 
who  have  some  acquantaince  with  mathematical  methods,  to  show  that  the 
flow  does  not  increase  indefinitely  with  the  temperature  T  of  the  air  in  the 
flue.   It  reaches  a  maximum  at  a  temperature  which  is  given  by  the  equation 


T  -t=  (459  +  Oa/i+- 


So   that  if  the  inlet  orifice  is  very   great  compared  with  the  outlet,   the 
maximum  is  reached  at  a  temperature   523  +  2,  {t  -  32)  ;  otherwise  the 
temperature  of  maximum  flow  will  be  much  higher  ;  indeed,  practically, 
the  inlet  orifice  is  very  small,  the  flow  increases  with  the  temperature  up  to 
the  limits  of  temperature  ordinarily  attainable. 

37.  Two  special  points  about  the  construction  of  chimneys  require  our  at- 
tention. First  it  is  usual,  in  register  grates  especially,  to  make  the  communi- 
cation between  the  fire-place  and  the  chimney  somewhat  smaller  in  area  than 
the  chimney  shaft ;  this  narrowed  area  is  called  the  throat  of  the  chimney. 
It  affects  the  resistance  by  requiring  the  velocity  of  the  air  to  be  increased  in 
order  to  get  the  same  flow  through  the  narrower  passage,  and  is  therefore  an 
artificial  contraction  of  the  orifice,  and  its  effect  may  be  represented  by  a 
suitable  coefficient  of  contraction.  If,  as  is  generally  the  case,  the  sides  of 
the  throat  are  coved,  then,  roughly  speaking,  no  coefficient  of  hydrodynamical 
contraction  will  be  required  for  the  throat  itself,  regarded  as  an  aperture,  so 
that  the  effect  of  the  throat  becomes  the  same  as  if  it  were  an  orifice  with  a 
coefficient  of  contraction  equal  to  the  ratio  of  the  measured  area  of  the  throat 
to  the  measured  area  of  the  shaft.  Let  f  be  this  ratio,  then  the  resistance  due 
to  the  throat  is 


t-4  \f       J  A2' 


64 

where  A  is  the  area  of  the  shaft. 

Secondly,  it  is  usual  to  provide  the  orifice  of  a  chimney  flue  with  a  chimney- 
pot. The  result  is,  generally  speaking,  a  narrowing  of  the  orifice  of  discharge, 
and  this  is,  from  the  scientific  point  of  view,  the  object  of  the  addition.  While 
the  area  of  the  shaft  of  the  chimney  should  be  decided  from  the  consideration 
of  the  greatest  possible  flow  of  air,  and  should  therefore  be  of  considerable  size, 
the  area  of  the  orifice  of  discharge  is  determined  with  a  view  of  securing  a 
sufficient  velocity  of  discharge  to  give  adequate  stability  to  the  draught. 
General  Morin  assigns  5  feet  per  second  as  the  proper  velocity  in  the  chimney 
and  10  feet  per  second  as  the  most  suitable  velocity  of  discharge.  The  best 
form  of  chimney-pot  is  one  in  the  form  of  a  truncated  cone  with  in-curving 
sides,  for  in  that  case  the  orifice  has  no  coefficient  of  hydrodynamical  con- 
traction per  se.  The  effect  of  such  a  chimney-pot  is  to  produce  an  arti- 
ficial contraction  from  the  area  of  the  shaft  to  the  area  of  the  orifice,  and  the 
effect  is  the  same  as  if  a  mouthpiece  were  adjusted  which  had  coefficient  of 

contraction  -r ,  where  a  is  the  area  of  the  orifice  and  A  that  of  the  shaft ;  the 

A. 

resistance  added  by  such  an  addition  to  the  shaft  is  therefore 


W     AV 


VOL.   I. 


98  HYGIENE 

Adopting  General  Morin's  figures  for  the  velocities,  a  would  be  one-half  of  A 

3        1 

and  the  resistance  of  a  chimuej^-pot  would  be  — — -  x  -^„,  where  A  is  the  area 

•'  ^  G4-4     A- 

of  the  shaft. 

Example. — Find  theflotu  of  air  through  a  room  with  an  open  fire,  and  find 

tlie  amount  of  coal  that  must  he  biiriied  to  maintain  it,  having  given  thefolloiv- 

ing  particulars.    Outlet : — A  chimney  of  circular  section  9  inches  in  diameter 

with  two  bends  of  45°  each,  the  first  at  a  height  of  10  feet  from  the  floor,  the 

second  at  a  height  of  11  feet,  the  remaining  vertical  portion  of  the  flue  being 

^5  feet.   The  chimney  is  provided  with  a  trumpet-shaped  cap  with  the  orifice 

G  inches  in  diameter.   The  throat  of  the  chimney  is  a  semicircular  area,  9  inches 

in  diameter,  '2.  feet  from  the  ground.    Inlet: — A  Tobin  tithe  Qx9  inches,  the 

inside  vertical  length  being  5  feet,  and  the  loioer  part  horizontal  and  2  feet 

long,  covered  by  a  grating  of  tvhich  half  the  area  is  occiipied  by  the  bars. 

Temperature  of  air  in  the  flue  182°  F.     Temperature  of  external  air  32°  F. 

Head. — If  we  neglect  the  small  loss  of  head  due  to  the  fact  of  the  cold 

air  having  to  be  forced  up  the  5  feet  of  Tobin  tube  (which  -will  depend  on  the 

difference  of  temperatm-e  of  the  external  air  and  the  air  of  the  room)  the  head 

lb  will  be==^  X  40  feet  of  air,  since  the  total  vertical  height  above  the  throat 
491 

is  40  feet. 

The  resistance  of  the  outlet  will  be  made  up  as  follows  : — 

Resistance  due  to  the  throat  (assuming  that  the  sides  leading  to  it  are  coved 

BO  as  to  give  a  coefficient  of  contraction  equal  to  unity), 


''■''mi 


=  -3G0. 


Resistance  due  to  friction  (hydrauhc  mean  radius  '19  foot), 

'01x43      1^ 

•19  X  32-2  •   f    /4-5N 

Resistance  due  to  bends. 


64-4        2  '     /4-5\2  ]  2 


Resistance  due  to  cap, 

1    /  1 

64-4 


'0'}^  {<'m 


=  -323. 


Coefficient  of  head  spent  in  producing  velocity, 

1    X   ,     }.  . ..  .  =-.  -403. 
g4.  ■ 


"  {m 


Total  resistance  of  outlet,  Ri  =  1-405. 

Besistance  of  inlet : — 

Resistance  of  grating  (coefficient  of  contraction  "GS), 


M(-A4r'(b'^' 


3\^^=-07O. 


WABMING  AND   VENTILATION  99 

Eesistance  due  to  friction  (hydraulic  mean  radius  0"15  ft.), 
•01x7     ,.        1 


•15x32-2 


(14) 


•103. 


Eesistance  due  to  one  rectangular  bend, 


g^x7r^.=-"0- 


Total  resistance  of  inlet,  E2  =^283 


Flo"W=  A  /  .^   ^  =2-69  cubic  feet  per  second. 
V    E1+E2 

The  amount  of  coal  required  to  be  burned  for  this  circulation  can  be 
determined  from  the  flow,  with  the  knowledge  of  the  amount  of  heat 
developed  by  the  combustion  of  1  lb.  of  coal  (p.  122),  the  density  and  specific 
heat  of  air,  and  the  given  rise  of  temperature. 

38.  It  remains  for  us  to  consider  the  local  circulation  in  such  a  room  as 
here  discussed.  If  the  inlets  all  supply  cold  air  the  distribution  of  the  air  on 
entering  may  be  inferred  from  fig.  29  (p.  90) .  It  results  in  the  formation  of  a  layer 
of  cold  air  on  the  floor,  moving  with  appreciable  velocity  towards  the  fireplace 
and  causing  a  cold  draught  to  the  feet.  This  will  be  the  case  in  a  large  room, 
even  if  the  air  is  directed  into  the  room,  by  Tobin  tubes  or  otherwise,  with  a 
vertical  motion ;  in  a  small  room  the  greater  part  may  be  occupied  by  the 
descending  shower  indicated  in  fig.  29,  and  the  cold  layer  may  not  have  space 
to  form.  This  effect  might  be  modified  to  a  certain  extent  by  having  a  large 
number  of  narrow  Tobin  tubes  made  of  metal,  instead  of  a  single  one  made 
of  wood,  as  the  air  would  in  the  former  case  issue  from  the  tubes  more 
nearly  at  the  temperature  of  the  room,  whereas  with  a  good  thick  wooden 
case  the  air  is  kept  as  nearly  as  may  be  at  the  external  temperature  until  it 
is  actually  in  the  room. 

There  will  be  rapids  at  each  inlet  orifice  and  in  the  immediate  neighbourhood 
of  the  grate,  but  their  effect  is  not  very  conspicuous  unless  the  air  is  very  cold. 
The  general  type  of  local  circulation  for  a  room  with  an  open  fire  and 
cold  air  inlets  will  therefore  be  rapids  at  entry  and  exit  and  a  cold  layer  from 
one  to  two  feet  thick  on  the  floor  moving  towards  the  fire.  It  is,  however,, 
interfered  with  by  local  causes,  the  most  important  of  which  are  the  surfaces 
considerably  heated  by  direct  radiation  from  the  fire.^  In  particular,  the  floor 
immediately  in  front  of  the  fire  gets  warmed  in  this  way  and  helps  to  warm 
the  air  passing  over  it,  and  if  the  radiation  is  sufficiently  intense  and  the  flow 
restricted,  a  column  of  ascending  air  is  formed  in  front  of  the  grate  and  the 
fire  is  fed  by  the  cold  air  from  the  sides  coming  round  the  rising  column.  A 
fender  which  screens  the  hearth-rug  from  the  direct  radiation  of  the  fire  keeps 
the  rising  column  within  its  own  area,  where  it  may  often  be  easily  detected. 
If  the  entering  air  is  warmed  to  a  temperature  the  same  as  that  of  the 
room  it  wiU  mix  more  completely  with  the  air  of  the  room,  and  the  formation 
of  a  current  along  the  floor  will  be  avoided.  If  its  temperature  exceeds  that 
of  the  air  of  the  room,  a  layer  of  warm  air  will  be  formed  at  the  ceihng,  and 
will  of  course  ultimately  fill  the  room  unless  it  escapes  by  ventilators  in  the 
ceiling.  It  becomes  mixed  with  the  respired  air  rising  from  the  occupants  of 
the  room,  so  that  adequate  ventilation  with  warmed  air  requires  the  full 
supply  specified  in  section  52). 

39.  An  interesting  case  of  local  circulation  occurs  when  a  room  with  an  open 

'  See  the  distribution  of  the  temperature  in  the  figure,  p.  110. 


100 


HYGIENE 


fire  and  cold  air  inlets,  or  no  special  inlets,  is  also  lighted  by  a  number  of  gas 
jets  on  the  same  level.  As  shown  later,  p.  115,  the  intense  heat  of  the  bm-ning 
gas  causes  a  local  circulation  which  does  not  practically  extend  below  the 
plane  of  the  burners  ;  we  then  get  the  room  divided  into  three  almost  inde- 
pendent zones,  a  torrid  zone  from  the  ceiling  to  somewhat  above  the  level  of 
the  gas  jets,  mainly  occupied  by  very  foul  air,  especially  in  the  upper  part ; 
a  frigid  zone  extending  from  the  floor  to  about  one  foot  in  height  occupied 
by  the  fresh  entering  air  on  its  way  to  the  fire :  between  these  two  is  a 
temperate  zone  of  air  without  any  special  circulation.  Diffusion  and  special 
local  causes  produce  a  certain  amount  of  intermingling  of  the  air  of  these 
three  zones,  and  in  particular  the  boundary  between  the  torrid  and  the  tem- 
perate zones  is  very  ill-defined,  the  temperature  rising  gradually  towards  the 


Fig.  32. 

ceiling  where  it  is  very  high  ;  but  the  separation  is  fairly  complete,  and  thus 
the  effect  of  burning  a  number  of  gas  jets  as  described  is  practically  to  reduce 
the  height  of  the  ceiling  of  the  room.  The  state  of  the  air  in  the  temperate 
zone  is  not  generally  regarded  as  unendurable,  but  the  occupants  would  be 
much  better  supplied  if  they  could  breathe  at  a  lower  level  than  is  usually 
the  practice.  An  ideal  diagram  of  the  stream  lines  of  the  local  circulation 
in  this  case  is  given  in  fig.  32. 

A  diagram  showing  a  special  instance  of  local  circulation  in  a  room  with 
an  open  fire  is  given  later,  p.  110. 

4.    KOOM   WITH    ONE    OuTLET    AND    SEVERAL   InLETS 

40.  We  have  already  indicated  the  treatment  of  this  case.  If  the  inlets  are 
direct  from  the  open  air,  or  cold  air  inlets,  they  are  equivalent  to  a  single 
inlet  with  an  equivalent  orifice  equal  to  the  sum  of  the  equivalent  orifices  of 
the  separate  inlets.  If  they  are  hot  air  inlets,  there  may  be  some  appreciable 
head  due  to  the  inlet  itself  which  must  be  allowed  for.  Thus  if  the  outlet 
head  would  produce  a  partial  head  h^  for  one  inlet  duct,  and  the  duct  itself, 
reckoned  separately,  produces  a  head  H'  the  actual  effective  head  for  that 
duct  would  be  h^  +  H',  and  the  flow  must  be  calculated  accordingly. 

5.  EooM  WITH  TWO  Outlets  and  one  Inlet 

41.  This  is  a  case  of  very  frequent  occurrence,  being  realised  whenever  a 
separate  ventilator  is  provided  with  special  flue  to  take  away  heated  air  in  a 


WABMING  AND   VENTILATION  101 

room  which  has  an  open  fire.  One  of  the  most  frequent  plienomena  exhibited  is 
that  the  ventilating  shaft  acts  as  an  inlet  and  lets  in  cold  air  instead  of  removing 
warm  air.  The  reason  for  this  back  draught  we  shall  endeavour  to  explain. 
Suppose  1b  the  total  head  due  to  the  chimney  ;  it  may  be  divided  into  two 
partial  heads,  h^  for  the  chimney  regarded  as  a  duct,  and  h.2  for  the  flow 
through  the  inlet.  Let  Ej  be  the  resistance  of  the  chimney,  R2  that  of  the 
inlet  duct.  Let  H'  be  the  separate  head  for  the  ventilating  flue,  depending 
on  the  difference  between  the  temperature  of  the  air  in  it  (and  in  the  room) 
and  that  of  the  outside  air  ;  then  the  effective  head  for  that  shaft  is  II'  — h.^, 
since  the  flow  for  the  two  heads  separately  would  be  in  opposite  directions. 
Thence  if  H'  =  /ij,  the  head  becomes  zero,  and  the  flow  through  the  venti- 
lator ceases,  and  at  that  instant  the  ventilator  does  not  affect  the  circula- 
tion through  the  room  which  would  be  produced  by  the  chimney  alone. 
We  can  therefore  calculate  hc^  as  though  the  ventilator  were  closed.  But 
since  h2  =  R2  V^,  and  hy  =  ElV^  and  1b  —  ^^-i  +  /i2» 

we  have  =--rr — "^^ft. 

ID        El  +  Ea' 

And  the  condition  for  cessation  of  flow  is,  therefore, 

W  ^       Bj,  H'      ^  E., 

lb    El  +E2'  ""  tf-H'    e; 

Now  the  head  H'  =-— 7^ (T'  —  t)  W,  where  T'  is  the  temperature  of 

459  +  t 

the  air  in  the  ventilating  flue  and  H'  its  height  from  the  room  floor  to  the 
external  orifice,  and  a  similar  relation  holds  for  the  head  for  the  chimney, 
so  we  get  the  following  result : — The  ventilator  ceases  to  draw  air  from  the 
room  as  soon  as  the  inlet  orifice  is  so  narrowed  that  the  ratio  of  the  resist- 
ance of  the  inlet  to  that  of  the  chimney-flue  is  equal  to,  or  greater  than^ 
•the  ratio  of  (T'  -  t)  W  to  {T  -  t)  H  -  (T'  -  t)  H'.  Supposing  that  the 
chimney  and  ventilating  flues  are  of  equal  height,  the  ratio  becomes 
T'  —  ^  :  T  —  T'.  That  is,  for  the  ventilator  to  act,  the  excess  of  temperature 
of  the  air  in  the  flue,  above  that  of  the  outside  air,  must  bear  a  greater  ratio 
to  the  excess  of  temperature  in  the  chimney  over  that  of  the  air  in  the  flue 
than  the  ratio  of  the  resistance  of  the  inlet  to  that  of  the  chimney.  If 
«  and  a'  be  the  equivalent  orifices  of  the  chimney  and  inlet  respectively 

_i  =  " 

E2        a 

whence  we  get : — the  condition  for  action  of  the  ventilator  is  a^a  must  be 
greater  than  ^  /  ± ±_. 

Thus  it  appears  that  with  a  given  chimney  the  action  of  the  ventilator 
depends  upon  the  area  of  the  orifice  of  inlet,  and  if  we  take  as  an  instance  a 
chimney  whose  equivalent  orifice  is  30  square  inches  with  the  temperature 
of  the  air  in  its  flue  250°  F,  and  that  of  the  air  in  the  room  and  ventilating 
flue  70°  F.,  the  outside  air  being  at  50°  F.  the  ventilator  will  cease  to  act 

if  the  inlet  orifice  is  less  than  a  /  ~        x  30    square    inches,   i.e.   90 

V         <U  —  50 

square  inches. 

This  area  of  inlet  is  seldom  realised  in  practice,  and  therefore  it  is  not 
surprising  that  under  ordinary  circumstances  a  ventilator  nearly  always 
declines  to  act  as  intended. 

We  have  found  the  condition  that  the  head  for  ventilation  in  the  flue  is 


102 


HYGIENE 


exactly  balanced  by  the  partial  bead  produced  by  the  chimney ;  but  such 
balancing  can  be  only  instantaneous,  lor  the  equilibrium  is  unstable.  If  the 
cold  outside  air  penetrates  a  little  way  down  tlie  Hue,  the  head  for  outward 
flow  is  reduced  in  consequence,  and  cannot  any  longer  sustain  the  pull 
of  the  partial  head,  so  the  cold  air  flows  further  down,  and  the  head  is 
thereby  still  further  diminished,  and  so  the  ventilator  immediately  acts  as 
an  inlet  instead  of  a  balanced  outlet,  and  here  an  interesting  point  becomes 
clear.  In  order  to  resuscitate  the  outflow  when  the  inlet  is  enlarged  to  a 
sufidcient  size  to  maintain  it,  if  it  were  once  established,  we  require  a  head  in 
the  flue  ;  but  this  cannot  arise  until  the  flue  is  filled  with  warm  air,  and 
this  will  not  naturally  occur,  as  it  now  acts  as  an  inlet.  It  may  occur 
fortuitously  by  the  action  of  a  gust  of  wind  across  the  top  of  the  flue  ;  other- 
wise it  can  only  be  restarted  by  increasing  the  inlet  to  such  a  size  that  the 
partial  head  produced  by  the  chimney  is  so  reduced  that  the  head  due  to  the 
warm  air  in  the  room  is  sufflcient  to  overcome  the  flow  down  the  ventilator 
and  start  a  fresh  flow  upward. 

G.  KooM  WITH  TWO  Inlets  and  two  Outlets 

42.  We  shall  consider  only  the  special  case,  when  the  two  o^itlets  have 
equal  heads,  and  we  shall  investigate  the  conditions  under  which  the  flow 
through  one  inlet  shall  be  adequate  to  supply  the  one  outlet,  while  the 
second  outlet  is  fed  entirely  by  the  second  inlet,  so  that  the  complex  venti- 
lation system  may  be  divided  into  two  separate  simple  systems.  One  of  its 
practical  apphcations  is  as  follows.  Suppose  two  adjoining  rooms  (fig.  33 )  with 
a  door  between  them  have  each  an  open  fire,  and  neither  of  them  is  pro- 


IR, 


/ 


u 


R' 


Fig.  33. 


vided  with  any  special  inlet.  Suppose  that  the  height,  and  the  temperature 
of  air  in  each  chimney  are  the  same,  will  there  be  any  flow  of  air  between  the 
rooms,  and  if  so  in  which  direction  ? 

If  the  rooms  communicate  by  a  large  opening  like  that  left  by  an  open 
door,  there  may  be  local  circulation  between  the  two.  This  we  are  not  con- 
sidering, and  therefore  we  shall  suppose  that  the  area  of  communication  is 


WARMING  AND   VENTILATION  103 

very  small,  by  means,  for  instance,  of  a  narrow  tube.  We  may  represent 
the  arrangement  by  fig.  33,  in  which  T  represents  the  tube.  If  there  is  no 
flow  through  this  tube  the  two  systems  will  be  independent,  and  can  be 
treated  as  if  the  tube  were  actually  closed.  On  this  assumption  the  head 
1b  for  the  one  circulation  may  be  regarded  as  divided  into  two  partial 
heads,  h^  and  h^,  for  the  outflow  duct  and  inflow  duct  respectively.  Let  the 
resistances  of  these  ducts  be  E,  and  K2  respectively  ;  then  we  have 

h,  =  EiV2,  h,  =  K2V2 ; 

.   K  _     B2 
•  *  lb      E,  +  Eg* 

If  1b',  ^^'^2,  E/,  Eg'  be  corresponding  quantities  for  the  second  circulation, 
we  have  in  precisely  the  same  way, 

lb'       E/  +  E/* 

Now  7i2  is  the  head  for  inflow  or  difference  of  pressure  between  the  one 
room  and  the  outside  air,  and  h^'  is  the  difference  of  pressure  between  the 
other  room  and  the  outside  air  ;  hence  if  these  two  are  equal  the  pressure  will 
be  the  same  throughout  the  two  rooms,  and  no  cross  flow  will  take  place.  The 
condition  of  no  cross  flow  is  therefore  h.2  =  h^',  and  if  /z-g  be  greater  than  Ag' 
iihe  flow  will  be  in  the  direction  from  the  second  room  to  the  first.  Since 
we  supposed  the  temperature  in  the  two  chimneys  to  be  the  same  we  have 
lb  =  lb'.    Hence  the  condition  is 

Ea  _  ^       E./ 
El  +  E2       E/  +  E2' 

E,       E/ 

■or  — -= — -. 

E2       E2' 

In  words : — There  wiU  be  no  flow  between  the  rooms,  or  the  two  circulations 
will  be  independent,  if  the  ratios  of  the  resistance  of  inlet  and  outlet  be  the 
same  for  the  two  circulations ;  and  if  the  ratio  of  inlet  to  outlet  be  greater 
for  the  one  circulation  than  the  other,  there  will  be  a  flow  from  the  circula- 
tion with  the  greater  ratio  to  that  with  the  less  ratio. 

This  condition  has  been  tested  experimentally  on  a  smaU  scale  and  found 
to  apply  with  very  great  accuracy.^ 

We  have  assumed  the  head  for  each  of  the  two  circulations  to  be  the 
same  ;  it  is  evident  that  a  condition  can  be  obtained  in  like  manner  if  that 
is  not  the  case  ;  but  it  leads  to  somewhat  more  complicated  expressions.  The 
reasoning  shows  very  clearly  the  precautions  that  must  be  taken  to  isolate 
.  any  circulation  without  actually  completely  separating  the  rooms,  or  at  any 
rate  to  secure  that,  if  two  circulations  interfere,  the  air  shall  pass  between  the 
two  in  a  given  direction.  Take,  for  instance,  the  following  case.  One  room 
•of  a  house  is  occupied  by  an  infectious  fever  patient,  and  it  is  desirable  to 
•adopt  precautions  to  prevent  the  air  of  the  patient's  room  passing  into  the 
house.  The  provisions  to  be  aimed  at  are  first,  an  outlet  duct  with  a  head 
for  ventilation  in  the  room  itself;  an  open  fireplace  and  chimney  will, 
•of  course,  suffice,  and  the  higher  the  temperature  of  the  air  in  the  chimney 
the  better ;  secondly,  the  ratio  of  the  equivalent  orifice  of  inlet  to  that  of 
the  chimney  must  be  at  any  rate  not  greater  than  the  corresponding  ratio 
for  the  adjoining  spaces  ;  in  the  absence  of  special  measurements  make  the 
inlet  openings  in  the  infected  space  small,  and  the  inlet  openings  for  the 
rest  of  the  house  as  large  as  possible. 

'  Shaw,  Proc.  Boy.     Soc.  March  1800. 


Wi  HYGIENE 


EXPERIMENTAL  INVESTIGATION  OF  THE  ACTION  OF  A  VENTILATION 
SYSTEM.  INSTRUMENTS  FOR  DETECTING  AND  MEASURING  CURRENTS 
OF  AIR 

43.  In  considering  tlie  practical  applications  of  the  principles  which  have 
been  laid  down  in  the  preceding  pages  it  will  be  at  once  evident  that 
successful  veAtilation  must  satisfy  two  fundamental  conditions.  For  the 
sake  of  clearness  we  will  continue  to  regard  the  ventilation  system  as 
represented  by  a  single  chamber  to  be  supplied  with  air,  and  therefore  pro- 
vided with  inlets  and  outlets.  The  two  fundamental  conditions  are  :  (1) 
That  sufficient  air  should  be  made  to  flow  through  the  system ;  (2)  that  on 
passing  into  the  chamber  it  should  be  so  distributed  as  to  replace  foul  air 
and  not  to  cause  cold  draughts.  We  wish  now  to  deal  with  the  methods  of 
determining  in  what  way,  and  to  what  extent,  a  particular  ventilation  system 
is  faulty  with  respect  to  these  two  fundamental  conditions.  Unsuccessful 
ventilation  is  of  course  generally  detected  by  anyone  who  has  the  misfortune 
to  be  exposed  to  it,  without  any  special  directions  for  finding  it  out.  But  it 
is  important  to  be  able  to  decide  whether  the  want  of  success  is  due  to  want 
of  air  or  misdirection  of  air,  and  in  the  latter  case  to  find  out  where  the  air 
is  going  to,  whether,  in  fact,  the  fault  lies  in  the  '  general  circulation  '  or 
in  the  '  local  circulation.'  The  two  conditions  which  have  been  laid  down 
may  most  conveniently  be  treated  separately.  We  shall  first  mention  the 
apparatus  by  Avhicli  an  examination  of  the  system  should  be  made. 

Examination  of  the  General  Cikculation 

44.  The  question  whether  the  air-supply  is  sufficient  is  capable  of  being 
tolerably  accurately  answered,  provided  that  the  outlets  or  the  inlets  can  all 
be  identified  and  measured  with  sufficient  accuracy.  It  must,  of  course,  be 
remembered  that  if  special  inlets  are  provided  the  air  will  not  necessarily 
pass  through  them  exclusively.  A  difference  of  head  determines  a  flow  of 
air  through  every  orifice,  great  or  small,  whether  intended  for  the  admission 
of  air  or  not.  For  the  same  difference  of  head,  the  flow  is  proportional  to 
the  area  in  a  thin  plane  wall  which  would  be  equivalent  to  the  orifice.  If 
an  alternative  opening  is  provided  which  is  very  ample,  the  head  for  a 
casual  orifice,  or  crevice,  may  be  very  much  reduced,  but  it  will  not  be 
absolutely  zero,  so  that  there  Avill  always  be  some  flow  through  the 
crevice.  We  shall  suppose,  however,  that  the  doors  and  windows  are 
sufficiently  well  fitted  to  prevent  any  considerable  flow  through  the  joints  if 
the  room  be  provided  with  special  inlets.  In  that  case  we  can  measure  the 
circulation  by  measuring  the  area  of  each  inlet  and  the  mean  velocity  of  the 
air  passing  through  it.  The  area  of  the  shaft  can  be  calculated  from  a 
scale  plan  of  its  section.  If  the  opening  is  covered  by  a  grating  it  is  better 
to  adapt  a  continuation  of  the  shaft  in  zinc  or  cardboard.  The  velocity  may 
be  measured  by  an  anemometer,  or  air-meter ;  the  pattern  most  frequently 
used  is  a  light  wheel  with  inclined  vanes  and  furnished  with  counting  gear 
and  dials.  The  instrument  is  represented  in  fig.  34,  and  is  made  by  Casella 
and  other  instrument-makers.  The  instrument  records  directly  the  velocity 
of  the  air  in  feet  per  minute  by  an  observation  of  the  graduations  jDassed  over 
by  the  needle  in  the  same  period,  but  a  correction  must  be  added  to  each 
observation  representing  the  minimum  velocity  which  will  move  the  vanes. 
The  correction  amounts  to  about  30  feet  per  minute,  or  G  inches  a  second;. 


WABMING  AND   VENTILATION 


10.': 


it  is  determined  by  the  instrument-maker  before  the  instrument  is  sent  out. 
It  could  be  verified  by  carrying  the  instrument  along  for  a  known  distance 
in  still  atmosphere  or  by  mounting  the  instrument  at  the  end  of  a  long  arm 
attached  to  a  revolving  table,  measuring  the  circumference  of  the  circle  so 
described,  and  comparing  it  with  the  result  given  by  the  anemometer  after 
a  complete  revolution. 

In  order  to  determine  the  mean  velocity  for  the  inlet,  care  must  be  taken 
to  observe  the  velocity  at  a  number  of  different  points — some  near  the  edge 
others  near  the  middle — and  take  the  mean  of  the  measurements,  or  to  keep 
the  anemometer  moving  slowly  across  the  aperture  during  an  observation. 

Having  determined  the  mean  velocity  and  the  area,  the  product  gives  the 
circulation  in  cubic  feet  per  minute.  The  weight  delivered  per  second  can 
easily  be  calculated  if  required.  "When  the  delivery  for  each  inlet  has  been 
measured  the  total  delivery  for  the  whole  circulation  is  obtained  by  adding. 

If  there  are  no  special  inlets  the  determination  of  the  circulation  must 
be  obtained  from  measurements  of  the  flow  through  the  outlets,  provided 
these  are  sufficiently  definite.  In  order  to  determine  the  flow  of  air  up  a 
chimney  the  front  of  the  fireplace  should  be  covered  Avith  a  case  in  which  an 
aperture  of  known  area 
is  cut  and  fitted  with  a 
tube.  But  it  must  be 
remembered  that,  unless 
the  area  of  the  aperture 
is  very  large  compared 
with  the  equivalent  ori- 
fice of  the  chimney,  the 
introduction  of  the  case 
with  aperture  will  affect 
the  flow  by  affecting  the 
total  resistance. 

Thus,  either  the 
amount  of  air  which 
enters,  or,  what  must  be 
the  same,  the  amount  of 
air  which  leaves,  can  be 
experimentally  determined.  If  both  can  be  measured  the  determination  of  the 
one,  of  course,  checks  that  of  the  other.  We  next  require  to  know  the  tem- 
perature of  the  air  as  it  enters ;  any  ordinary  thermometer  may  be  used 
for  this  ]purpose,  but  it  must  be  used  with  discretion,  for  the  reading  of  the 
thermometer  depends  not  only  on  the  temperature  of  the  air  in  which  it  is 
placed,  but  also  on  the  radiation  it  receives  from  hot  bodies  near ;  moreover, 
the  temperature  of  the  entering  air  may  not  be  the  same  at  every  part  of  the 
orifice.  The  determination  of  the  temperature  of  the  air  with  the  highest 
accuracy  is  a  very  difficult  matter,  but  for  the  ordinary  purposes  of  an  investi- 
gation of  the  ventilation  circulation  in  a  system,  it  is  sufficient  if  the  thermo- 
meter be  simply  exposed  in  the  air  of  the  delivery  shaft  screened  from  direct 
radiation,  secured  from  contact  with  the  sides  of  the  shaft,  and  left  until 
no  change  of  reading  occurs  during  an  interval  of  a  few  miniites.  The  thermo- 
meter should  be  of  course  read  tn  situ,  and  not  brought  away  from  the  point 
at  which  the  temperature  is  required  until  the  reading  is  taken. 

It  remains  only  to  consider  whether  the  air  is  satisfactory  as  to  quality. 
In  order  to  test  this  point  a  determination  of  the  composition  of  the  air  must 
be  made,  or,  at  any  rate,  the  amount  of  impurity  must  be  determined.  For 
information  on  this  point  the  reader  is  referred  to  the  article  Am. 


106 


HYGIENE 


The  amount  of  moisture  in  the  air  is  an  important  element ;  it  can  be 
determined  by  any  one  of  the  hA'grometric  methods  referred  to  in  the  article 
Meteorology.  It  is  liable  to  vary  considerably  in  different  parts  of  the 
circulation. 


Fig.  35. 


Direct  Measurement  op  Head  or  Pressure  Differences 

45.  Another  element  which  can  sometimes  be  measured  directly  is  the 
difference  of  pressure  of  air  between  the  two  ends  of  a  duct,  and  from  the 
pressure  difference,  the  head  in  feet  can  be  easily  deduced.     The  usual  m- 

struments  for  measuring  the 
pressure  of  air  are  not,  as  a  rule, 
sufficiently  sensitive  for  the  pur- 
poses of  ventilation-measure- 
ment, as  the  pressure  differences 
are  very  minute.  In  some  cases, 
however,  where  the  head  re- 
quired is  large,  as,  for  example, 
in  the  ventilation  of  mines,  a 
syphon  water-gauge — a  U  tube 
containing  water  in  the  bend  and 
having  one  hmb  connected  by 
tubes  with  one  end  of  the  ventila- 
tion system  and  the  other  limb 
open  to  the  other  end — will  serve 
to  give  the  pressure  in  inches  of 
water  by  reading  the  difference 
of  level  of  the  water  in  the  two 
limbs. 

An  aneroid  barometer  read- 
ing to  one-thousandth  of  an  inch 
can  also  be  obtained,  and  this 
may  be  used  for  observations  in 
examining  the  ventilation  of  a 
house  ;  but  with  such  an  instru- 
ment, indicating  as  it  does  the 
pressure  of  the  air  where  it  is 
placed,  a  double  observation  is 
necessary  to  get  the  pressure 
difference  for  the  tAVO  ends  of  a 
duct. 

There  are  numerous  devices 
which  have  been  adopted  for 
increasing  the  accuracy  of  the 
reading  of  the  syphon  water-gauge.  In  one  modification  the  one  limb  of  the 
gauge  is  expanded  into  a  large  square  box,  while  the  other  is  a  vertical  glass 
tube  in  which  the  rise  or  fall  of  the  water  can  be  measured  by  the  distance 
through  which  a  sharp  needle-point  originally  set  at  the  surface  of  the  water, 
forming  the  end  of  a  micrometer  screw,  has  to  be  moved  in  order  that  it  shall 
again  be  at  the  water- surface.  The  adjustment  of  the  point  can  be  identified 
with  very  great  precision,  because  the  image  of  any  object  formed  by  reflection 
at  the  water  surface  is  distorted  as  soon  as  contact  takes  place  with  the  point. 
A  figure  of  such  an  instrument  taken  from  Peclet's  '  Traite  de  la  Chaleur,' 
vol.  i.  §  523,  is  reproduced  in  fig.  35. 


Fig.  36. 


WABMING  AND   VENTILATION 


107 


The  identification  of  the  position  of  the  surface  is  still  easier  if  the  needle- 
point be  below  the  surface  and  brought  up  to  it  by  the  motion  of  a  screw, 
the  most  minute  elevation  of  the  point  above  the  surface  being  readily 
perceived.  In  this  case  the  reading  can  still  be  made  by  a  micrometer  screw 
if  the  needle  is  bent  into  a  hook  form  so  that  the  point  turns  upwards.  A 
modification  which  dispenses  with  the  necessity  for  a  screw  has  been  de- 
signed by  Mr.  H.  Darwin,  of  the  Cambridge  Scientific  Instrument  Co.,  and 
a  model  constructed  and  tested  by  the  writer  of  this  article.  In  this  in- 
strument (fig.  36)  the  needle  is  fixed  to  the  bottom  of  a  water  or  oil  vessel 
and  the  measurement  is  carried  out  by  observing  how  much  water  must  be 
added  or  removed  in  order  to  bring  the  point  of  the  needle  to  the  surface 
again  after  it  has  been  protruded  or  withdrawn  by  the  alteration  of  level  duo 
to  the  difference  of  pressure.  The  amount  of  water  which  would  be  required 
for  this  purpose  is  determined  by  finding  the  extent  to  which  a  plunger,  a 
uniform  and  graduated  glass  rod,  must  be  pushed  down  or  withdrawn  from  a 
small  well  formed  by  a  vertical  tube  communicating  with  the  water  vessel. 
From  some  tests  of  the  instrument  made  for  the  Author  by  Mr.  A.  Schneider, 
of  Emmanuel  College,  it  appears  that  the  instrument  will  give  readings  to 
within  one-three-thousandth  of  an  inch. 

Another  modification  of  the  syphon  gauge  which  increases  the  sensitiveness 


Fig.  37. 


■consists  in  using  a  wide  vessel  for  one  limb  of  the  gauge  and  for  the  other 
a  long  inclined  straight  tube.  As  the  dift"erence  of  pressure  corresponds  to  a 
difference  of  vertical  height  of  the  two  water  surfaces,  the  water  has  to  traverse 
a  greater  length  of  inclined  tube  than  of  a  vertical  tube  in  order  to  produce 
the  same  difference  of  level ;  indeed,  the  length  of  tube  traversed  by  the  liquid 
in  an  inclined  tube  is  equal  to  the  vertical  difference  multiplied  by  1/sin  i, 
where  i  is  the  inclination  of  the  tube  to  the  horizontal.  The  area  of  the 
■surface  of  the  water  in  the  other  limb  must  be  very  great  in  order  that  the 
■elevation  or  depression  may  practically  take  efi^ect  solely  in  the  inclined  tube. 
A  form  of  this  apparatus  used  by  M.  Peclet,  and  described  by  him  in  his  treatise, 
vol.  i.  §  524,  is  represented  in  fig.  37. 

Many  other  arrangements  for  the  measurement  of  small  differences  of 
pressure  have  been  designed,  some  of  which  are  described  by  Peclet,  vol.  i. 
chap.  xi. 

Examination  of  the  Local  Cikculation  of  Air 

46.  While  it  is  in  many  cases  comparatively  easy  to  determine  the  total 
amount  of  air  supplied  to  a  room,  the  testing  of  the  second  condition  laid 
•down  above  as  being  requisite  for  successful  ventilation  is  by  no  means  easy. 
We  have  no  satisfactory  means  of  tracing  the  course  of  the  air  from  its 


108  HYGIEXE 

entrance  to  its  exit,  and  determining  its  state  as  to  temperature,  moisture, 
and  impurity  as  it  flows.  The  motion  of  the  air  is  not,  strictly  speaking, 
steady  in  an  occupied  room,  for  the  velocity  and  state  of  the  air  vary  from 
time  to  time.  The  representation,  by  means  of  a  diagram,  of  the  circulation 
in  a  room  is  almost  as  difficult  as  its  determination.  Any  sectional  plan  can 
only  satisfactorily  represent  the  flow  in  that  section,  and  the  flow  in  one 
plane  section  cannot  afl'ord  an  adequate  indication  of  the  whole  circulation 
in  the  room.  It  is  probable  that  the  difficulties  which  are  referred  to  above 
are  responsible  for  the  diagrams  employed  in  illustration  of  the  principles  of 
ventilation  being  frequently,  more  strictly  speaking,  finger-posts  to  show  where 
the  air  is  intended  to  go  than  actual  tracks  of  the  air.  Much  interesting 
information  is,  however,  always  to  be  obtained  even  from  the  little  that  can 
be  learnt  of  the  direction  and  magnitude  of  the  motion  of  air  in  different  parts 
of  a  room.  There  are  many  ways  in  which  information  can  be  got,  though  none 
of  them  are  completely  satisfactory.  The  air  from  dift'erent  points  can  be 
analysed  and  its  temperature  can  be  ascertained,  though  there  are  not  easy 
observations  in  a  room  of  any  considerable  size  and  height.  Further  than 
that,  accurate  numerical  measurements  are  not  really  practicable.  A 
very  light  wind  vane,  consisting  of  a  wire  with  a  paper  tail,  balanced  on  a 
needle-point  standing  in  a  glass  cup,  is  extremely  sensitive  to  horizontal 
motion,  and  indicates  by  its  oscillations  whether  there  is  vertical  motion  too. 
For  observations  of  vertical  motion,  a  piece  of  cork,  carrying  four  inclined  mica 
wings,  surrounding  the  end  of  an  inverted  thin  glass  test  tube,  can  be  supported 
by  a  needle-point  and  move  with  so  little  friction  that  it  will  easily  show  the 
air  current  rising  from  the  hand  placed  several  feet  under  it,  and  by  the- 
rapidity  of  its  rotation  indicates  satisfactorily,  though  roughly,  the  vertical 
velocity  of  the  air  which  passes  it.  By  having  a  sufficiently  large  number  of 
such  vanes  and  mica- spinners  placed  at  different  heights  and  different 
positions  in  a  room,  a  very  good  idea  can  be  formed  of  the  course  of  the  air 
currents,  which,  however,  it  is  very  difficult  to  adequately  represent  on 
paper.  There  are  various  ways  in  which  the  currents  may  be  made  more 
or  less  visible  by  loading  them  with  smoke  or  fumes  which  are  carried 
along  with  the  current.  Smouldering  cotton  velvet  is  recommended  as  being 
useful  in  this  way  ;  the  Commissioners  of  1857  '  placed  ammonia  in  a  dish 
in  the  path,  of  the  current  and  loaded  the  air  passing  it  with  hydrochloric 
acid  vapour.  Some  other  fuming  chemical  compounds,  as  stannic  chloride,, 
might  be  used,  but  all  these  are  liable  to  change  the  current  to  a  certain  extent,, 
and  without  exceptional  illumination  the  flow  is  not  visible  for  a  long  dis- 
tance. Balloons,  silk  fibre,  and  down  are  also  sometimes  employed,  and 
when  used  discreetly  may  afford  valuable  observations  ;  but  none  of  them 
seem  quite  so  trustworthy  as  the  wind  vanes  and  mica-spinners  mentioned 
above. 

The  most  sensitive  method  of  detecting  the  motion  of  air  for  some- 
purposes  is  by  means  of  the  sense  of  smell ;  the  path  of  air  through  the 
difl'erent  rooms  of  a  house  can  be  easily  traced  by  burning  a  little  incense  or 
a  pastille  (which  can  be  bought  at  any  chemist's)  near  an  inlet.  In  this  case 
we  have,  of  course,  auxiliary  information  as  to  the  path  by  which  smell 
comes  into  a  room  if  at  all,  viz.  through  crevices  or  openings  which  can,  as  a 
rule,  be  identified.  It  cannot  be  used  with  much  effect  in  a  large  room,  as 
the  path  of  currents  could  only  be  traced  by  the  observer  moving  about,  and 
this  moving  would  entirely  destroy  the  steadiness  of  the  currents  and  spoil 
the  observation.     The  sensation  of  a  cold  current,  especially  as  perceived  by 

'  Report  of  Farliaincntarij  Comviission  on  War/iiiiig  and  Ventilation  of  DivellingSy 
1857 


WABMING  AND    VENTILATION 


109 


a  moistened  finger,  may  also  be  used  to  furnish  information  as  to  the  direction 
of  flow  in  any  accessible  position. 

47.  It  will  be  gathered  from  the  above  that  the  information  which  can  be 
obtained  as  to  the  local  circulation  of  air  through  a  room  is  not  at  all  com- 
plete, and  is  difficult  of  representation  ;  but  with  one  or  other  of  the  apparatus 
mentioned,  and  by  taking  advantage  of  casual  indications  (such  as  the  deposit 
of  dust  on  walls,  which  is  a  good  indication  of  the  course  of  warm  air),  an 
observer  may  make  himself  tolerably  well  acquainted  with   the  course  of 


currents  through  the  room.  We  reproduce  diagrams  (figs.  38-41  and  Plate  I.), 
representing  the  results  of  experiments  of  this  kind,  which  will  serve  to  indicate 
the  general  features  that  may  be  expected  in  any  case.  The  first  two  diagrams 
refer  to  the  circulation  of  air  and  the  distribution  of  temperature  in  a  room 
with  an  open  fire,  which  were  very  fully  investigated  by  the  Commissioners  on 
Warming  and  Ventilation  of  Dwellings,  1857.  The  diagrams  are  taken  from 
their  report.  The  first  (fig.  38)  shows  the  direction  of  flow  along  the  ceiling 
by  the  direction  of  deflexion  of  silk  fibres  attached  to  the  ceiling,  while  the 
amount  of  the  deflexion  is  indicated  by  numbers  written  against  the  lines 


110 


HYGIENE 


1 


representing  the  fibres  as  seen  in  plan ;  the  second  (fig.  39)  shows  the  flow 
in  a  vertical  section  through  the  middle  of  the  room  by  representing  the 
deflexion  of  silk  fibres  and  also  by  some  lines  of  flow ;  the  temperature  in 
various  positions  is  also  indicated.  Fig.  40  represents  the  circulation  in  a. 
lecture-room  in  Cambridge  heated  by  hot-water  pipes  under  the  tiers  of  seats, 
and  ventilated  through  open  woodwork  in  the  ceiling  into  a  wooden  channel, 


extending  round  three  sides  of  the  room,  and  communicating  with  a  chimney 
at  the  corner  marked  F.  In  this  room  no  special  inlets  are  provided,  some  air 
comes  in  at  A  from  the  lobby,  and  passes  over  the  hot-water  pipes  ;  the  rest 
of  the  fresh  air  required  comes  in  by  the  joints  in  the  windows  ;  the  doors 
in  this  particular  instance  generally  act  as  outlets  in  consequence  of  the 
suction  from  other  parts  of  the  buildmg. 

In  the  diagram  (fig.  40)  the  full  arrows  show  the  flow  in  the  plane  of  the 
section,  while  the  dotted  arrows  indicate  currents  near  the  wall.     The  strong 


WABMING  AND    VENTILATION 


111 


upward  current  of  warm  air  at  the  back  of  the  room  is  very  clearly  shown  in 
the  room  itself  by  a  deposit  on  the  walls  and  ceihng. 

The  most  obvious  conclusion  to  be  drawn  from  the  diagram  is  that  the 
air  which  enters  from  the  chamber  containing  the  pipes  passes  directly  to  the 
extract  flue  (the  velocity  of  exit  is  at  the  jrate  of  300  cubic  feet  per  minute) 
without  affecting  the  main  body  of  the  air  in  the  room,  which  remains 
practically  unventilated  and  unwarmed.  The  circulation  is  very  much 
restricted  for  want  of  sufficient  inlets.  There  are  trap-doors  in  the  ceihng 
at  C  above  the  table,  communicating  with  an  airy  lumber-room,  and  the 
opening  of  one  of  these  determines  a  shower  of  cold  air  falling  directly  upon 
the  table.     The  doors  of  the  lecture-room  then  become  energetic  outlets. 

The  next  diagram  (fig.  41)  shows  the  circulation  on  a  stone  well-stair- 
case in  the  same  building ;  the  doorways  represented  communicate  with 
corridors  and  rooms  having  large  window  area.  There  is  a  coil  of  pipes  on 
the  ground  floor.     The  diagram  shows  a  hot  ascending  current  of  air  passing 


ViHTiLAnoH    Flue 


1    1    1 


\ 


t 


\ 


E 


E 


^ 


fe 


E. 


-    Scatt.rFtlT  - 


E. 


Fig.  40. 


up  the  well  of  the  staircase,  and  a  sort  of  river  of  cold  air  flowing  down  the 
steps  and  turning  the  corners,  part  of  it  finally  passing  down  into  the 
basement.  This  is  really  part  of  a  general  circulation  of  air  between  the 
hot-water  coils  and  the  windows  of  the  whole  building,  and  the  circulation 
can  be  easily  traced,  the  hot  air  passing  at  the  tops  of  the  doorways,  the  cold 
air  at  the  bottoms.  In  this  case  also  no  special  inlets  are  provided,  so  that 
the  circulation  is  mainly  internal. 

The  circulation  on  a  staircase  of  any  house  is  generally  instructive,  and 
a  cold  descending  current  from  the  chimneys  and  windows  of  the  cold  upper 
rooms  can  frequently  be  shown  to  be  active  simultaneously  vnth.  a  hot 
ascending  current,  generally  from  the  kitchen,  and  the  two  currents  escape 
mutual  destruction,  either  by  one  going  spirally  round  the  other,  as  on  the 
staircase,  fig.  41,  or  by  the  hot  one  passing  over  the  cold  one.  It  is  this 
complication  of  currents  that  accounts  for  the  thorough  diffusion  of  smells 
in  a  house.     I  have  found  when  experimenting  with  pastilles  upon  the 


112 


HYGIENE 


Fig.  41. 


WABMING   AND   VENTILATION  113 

circulation  in  a  house  (Plate  I.)  that  when  a  pastille  was  being  burned  on 
the  upper  floor  a  layer  of  air  twelve  inches  thick,  flowing  downstairs,  was 
charged  with  the  smell,  whereas  at  the  height  of  five  feet  the  smell  of 
cooking  was  going  upstairs.  I  have  attempted  to  represent  the  distribution 
of  currents  on  this  staircase  by  a  diagram  (Plate  I.),  where  a  full  arrow  denotes 
rising  warm  air  and  a  dotted  arrow  descending  cold  air.  The  only  means  of 
protecting  one's  self  against  such  inconveniences,  if  they  be  regarded  as  such, 
is  to  provide  a  competent  inlet  for  every  outlet  head,  and  to  provide  an  efficient 
outlet  head  for  every  room  where  air  is  likely  to  be  fouled,  or  charged  with 
disagreeable  odours. 

48.  The  examples  represented  in  these  diagrams,  with  those  given  in  figs. 
28,  29,  and  30,  §  31,  are  sufficient  to  indicate  the  two  main  difficulties  of 
ventilation  Avhich  arise  from  the  magnitude  of  the  space  to  be  ventilated.  They 
may  be  called  respectively  internal  circulation,  the  production  of  currents  on 
account  of  local  differences  of  temperature  by  which  warm  air  is  carried  away 
from  where  it  is  wanted  and  replaced  by  cold  air  causing  draughts  ;  and  selec- 
tive circulation — the  name  we  propose  to  apply  to  the  passage  of  air  from  an 
inlet  more  or  less  directly  to  an  outlet  without  replacing  as  fully  as  possible  the 
foul  air  of  the  room  it  is  designed  to  ventilate.  The  objects,  then,  of  an  in- 
vestigation into  the  ventilation  of  any  room  may  be  conveniently  referred  to 
under  the  headings :  sufficiency  of  supply,  internal  circulation,  and  selective 
circulation. 

The  defects  which  may  be  included  mider  the  second  and  third  headings 
are  especially  liable  to  be  serious  in  large  rooms,  particularly  when  there  are 
local  sources  of  heat  and  cold.  In  theatres  they  are  often  disagreeably 
prominent,  and  the  elaborate  arrangements  of  M.  Morin  and  others  are 
designed  to  obviate  them. 

Effect  of  Adjoining  Eooms 

49.  It  will  be  well  here  to  call  special  attention  to  a  matter  which  has  been 
frequently  alluded  to,  namely,  that  the  process  of  ventilation  is  a  circulation 
of  air  through  a  channel  which  must  have  two  ends,  each  end  being  in  the 
open  air.  The  investigation  of  the  ventilation  of  any  system  is  therefore 
not  complete  until  the  two  sections  of  communication  of  the  circulation  with, 
the  open  air  have  been  identified. 

In  investigating  the  circulation  of  any  room,  starting  from  the  outlet 
and  going  backwards  to  the  inlet,  we  must  retrace  the  course  of  the  air  until 
we  arrive  at  the  ultimate  inlet.  This  will  often  be  found  in  adjoining  rooms 
or  in  closets  communicating  directly  or  indirectly  with  the  room  in  question. 
In  respect  of  sanitary  matters  this  is  a  very  important  consideration,  and 
constitutes  a  valid  objection  to  the  general  principle  of  ventilation  by  suction. 
Let  us  consider,  for  example,  the  circulation  in  a  house  in  winter,  in  which 
a  number  of  rooms  have  fires,  each  of  which  causes  a  head,  drawing  air, 
we  will  suppose,  from  the  central  hall  or  lobby  (see  Plate  I.).  Then 
there  will  be,  in  consequence,  a  head  between  the  central  lobby  and  the 
external  air  which  will  determine  a  flow  of  air  through  every  orifice,  great  and 
small,  in  proportion  to  its  equivalent  area,  unless  there  is  a  countervailing 
head.  It  follows  that  all  closets,  cupboards,  rooms,  &c.,  which  have  an 
opening  to  the  external  air,  unless  provided  with  separate  flues  in  which 
a  head  is  maintained,  will  contribute  to  the  supply  of  air  to  the  central  lobby 
from  which  the  rooms,  at  any  rate  partially,  draw  their  air.  It  is  needless 
to  say  that  the  air  may  be  rendered  quite  impure  and  unfit  for  use  on  its  way 
to  the  lobby  and  the  room  that  receives  it.  Experiments  can  easily  be  made  on 
this  point  by  loading  the  air  in  the  places  where  there  are  inlets  with  incense 
vol,  I.  J. 


114  HYGIENE 

or  some  strongly  smelling  vapour,  as  that  of  oil  of  peppermint,  or  even  tobacco- 
smoke.  I  have  given  one  instance,  and  there  are  probably  many  in  which 
experiments  of  this  kind  have  shown  that  the  supply  of  air  for  the  fires  of 
most  of  the  living  rooms  Avas  mainly  drawn  from  the  w.c,  which  had  been 
provided  with  two  openings  to  secure  its  ample  ventilation.  In  the  absence 
of  special  inlets  both  these  openings  were  acting  as  inlets  for  the  house,  and 
the  current  of  cold  air  could  be  easily  traced  under  the  door  of  the  closet 
and  along  the  floors  of  the  lobby,  under  the  doors  of  the  living  rooms  to  the 
fires  ;  when  it  got  near  the  fireplace  it  was  warmed  and  rose,  and  so  the 
odour  gradually  permeated  the  whole  room. 

The  effect  of  adjoining  rooms  with  apparatus  for  separate  heads  for 
circulation  is  frequently  very  conspicuous.  In  one  instance  that  has  come 
under  my  notice  a  lobby  is  heated  by  a  ventilating  gas-stove  with  one 
flue  for  the  supply  of  fresh  air  and  another  for  carrying  away  the  products 
of  combustion.  In  the  adjoining  room  is  an  open  tire.  If  the  gas-stove  is 
lighted  when  the  fire  is  burning,  although  the  door  between  the  two  be  shut, 
no  upward  current  is  established  in  the  outlet  of  the  stove ;  it  continues  to  act 
as  an  inlet  for  the  next  room  ;  the  products  of  combustion  come  straight  out 
into  the  lobby  and  gradually  pass  into  the  adjoining  room,  where  they  are 
readily  perceived,  and  this  continues  for  an  indefinite  period  unless  free 
communication  be  made  between  the  lobby  and  the  external  air  by  opening 
the  door,  when  the  products  of  combustion  pass  up  the  flue,  and  there 
establish  a  head  sufficient  to  overcome  the  suction  of  the  next  room,  and 
thereafter  the  desired  circulation  persists  though  the  outer  door  be  shut.^ 

Aetificial  Lighting  and  its  Effect  on  Ventilation 

50.  We  have  already  noticed  that  every  local  source  of  heat  produces  con- 
vection currents  in  its  neighbourhood.  Of  such  local  sources  artificial  lights 
are  the  most  effective.  The  disturbance  which  they  produce  in  the  air 
depends  of  course  upon  the  amount  of  heat  which  the  glowing  substance 
communicates  to  the  air  surrounding  it,  and  consequently  an  incandescent 
electric  lamp  is  distinguished  among  aU  artificial  lights  by  the  smallness  of 
the  interference  with  the  ordinary  course  of  the  air  which  is  caused  when  the 
light  is  used.  It  is  further  distinguished  by  the  fact  that  being  inclosed  in 
a  glass  envelope  the  glowing  filament  produces  no  effect  upon  the  air  except 
the  small  amount  of  heating ;  it  requires  no  oxygen  for  the  maintenance  of 
the  light,  and  therefore  does  not  use  up  the  air  of  the  room,  whereas  other 
artificial  lights  use  the  oxygen  of  the  air  and  produce  carbon  dioxide  gas. 
The  following  table  shows  the  comparative  effect  of  different  sources  of 
artificial  light  in  respect  of  the  heat  which  they  produce,  and  the  heat  pro- 
duced by  a  human  being  is  likewise  included  for  the  sake  of  comparison : — 

Table  VII 


Source  of  heat 

Heat  developed  per  hour 

Cubic  feet  of  carhou 
dioxide  gas  per  hour 

Incandescent  lamp  (16  candle-power) 
Average  human  being 

Candle 

Average  gas  jet  (4  cu.  ft.  per  hour) 

200  lb.  F.  units 

284 

291 

2784 

0 
•6 

•45 
8 

It  follows  at  once  that  a  number  of  gas  jets  produce  as  much  heat  as  a 
coal  fire,  and  hence  when  burned  in  a  room  may  entirely  change  the  course 

'  For  the  explanation  of  this  effect  see  above,  §  41. 


WABMING  AND   VENTILATION  115 

of  the  currents  of  air,  while  at  the  same  time  they  dehver  a  large  amount  of 
carbon  dioxide  gas,  sulphur  dioxide  gas,  and  other  impurities,  so  that,  accord- 
ing to  Wolpert,  for  every  cubic  foot  of  gas  burned  1800  additional  cubic 
feet  of  fresh  air  should  be  introduced.  It  is  therefore  clear  that  a  system 
of  ventilation  designed  for  a  room  in  the  daytime,  when  no  artificial  light  is 
used,  ought  not  to  be  expected  to  be  successful  when  a  number  of  gas  jets  are 
burning  in  the  room. 

If  a  considerable  volume  of  gas  be  burned  in  a  room  that  is  unprovided 
with  special  exit  tubes  for  the  burnt  gas,  an  internal  circulation  is  set  up  by 
each  gas  jet ;  the  circulation  does  not,  however,  extend  below  the  level  of  the 
burners,  so  that  assuming  for  a  moment  that  the  burners  are  on  the  same 
level  the  air  in  the  room  is  divided  into  two  portions  by  the  horizontal  plane 
of  the  burners  (see  §  39),  and  as  the  combustion  proceeds  the  air  of  the  upper 
part  is  rapidly  converted  into  a  thick  layer  of  heated  foul  air,  which  no  human 
being  could  endure  for  any  length  of  time,  and  the  lower  section  is  com- 
paratively uninfluenced.  This  description  is  somewhat  exaggerated,  for  the 
local  circulation  produced  by  the  fire,  if  there  is  one,  and  by  other  sources 
of  heat,  and  the  process  of  difi'usion,  cause  the  products  of  combustion  of  the 
gas  to  be  gradually  disseminated,  but  the  mixture  is  by  no  means  complete 
in  ordinary  cases.  In  order  to  remove  the  vitiated  air  the  outlets  must  be 
placed  as  near  to  the  ceiling  as  possible  ;  if  they  are  flues  they  form  suction 
outlets,  which  require  a  corrresponding  flow  of  air  to  the  room.^  Un- 
doubtedly the  most  satisfactory  arrangement  is  to  provide  special  outlets 
to  carry  awa}''  the  products  of  combustion  directly  from  the  burners,  but  that 
does  not  alter  the  effect  on  the  ventilation  in  respect  of  the  greater  total 
circulation  of  air  required,  if  other  causes,  which  are  used  when  there  is  no 
gas,  are  still  active  when  the  room  is  lighted ;  so  that  the  problem  of 
ventilating  a  room  for  daylight  and  gas  light  is  really  a  double  one,  and  it 
may  not  be  possible  to  provide  a  satisfactory  solution  of  both  parts  of  it  by 
jneans  of  a  single  arrangement. 

Summer  and  Winter  Ventilation 

51.  Somewhat  similar  remarks  apply  to  the  ventilation  of  buildings  in 
summer.  In  an  ordinary  house  in  winter  the  chimneys  are  the  warmest  parts, 
and  hence,  even  when  no  fire  is  burning,  there  is  always  a  certain  amount 
of  head  due  to  he  higher  temperature,  although  the  motion  of  the  air  may 
be  reversed  in  consequence  of  a  more  powerful  head  in  an  adjoining  room. 
But  in  the  daytime  in  summer  the  chimneys  are  frequently  the  coldest 
portions  of  the  house,  whereas  the  sun  acting  on  the  external  walls  produces 
a  head  causing,  with  open  windows,  a  circulation  downward  through  the 
chimneys  and  through  the  window^  upwards  outside  the  house.  This  effect 
is  very  frequently  perceptible  by  the  smell  of  soot  that  occurs  on  very  hot 
days,  so  that  the  winter  arrangement  for  ventilation  entirely  breaks  down 
unless  some  special  device  is  adopted.  The  obvious  plan  in  this  case  is  to 
restore  the  upward  head  in  the  chimneys  of  those  rooms  that  require 
ventilation  during  the  day,  by  gas  jets  in  the  chimneys  or  some  other  means, 
-or  to  stop  up  the  chimneys  of  those  rooms  and  trust  to  open  windows  alone 
for  any  ventilation  that  is  necessary.  The  amount  of  gas  that  is  required 
-to  be  burned  for  the  purpose  of  producing  a  head  in  a  shaft  is  given  on  p.  84. 

*  For  the  condition  that  such  apparatus  should  act  as  desired  see  §  41. 

I  2 


116  HYGIENE 


Summary  of  Conditions  to  be  Satisfied  to  secure  Efficient 

Ventilation 

1.  Quantity  of  Air  Required 

52.  The  estimates  of  the  quantity  of  air  to  be  supphed  are  based  upon  the 
following  assumptions : — i.  That  the  air  of  a  room  must  not  be  permitted  to 
contain  more  than  two  volumes  of  carbon  dioxide  gas  per  10,000  in  excess  of 
that  contained  in  the  outside  air.  ii.  That  the  carbon  dioxide  generated  by 
respiration  or  combustion  is  diffused  uniformly  throughout  the  room,  as  like- 
v\dse  is  the  air  which  enters,  so  that  the  volume  to  be  supplied  is  that  required 
to  dilute  the  impurity,  the  average  production  of  CO.,  per  head  of  average 
population  being  -Q  cubic  foot  per  hour.  On  these  assumptions  the  quantity 
of  air  to  be  supplied  per  hour  for  a  room  in  continuous  occupation  is  3000' 
cubic  feet  per  average  occupant,  or  more  particularly  : 

9800  cubic  feet  per  hour  for  each  adult  male  in  hard  work. 
4750         ,,  ,,  ,,  ,,  ,,     in  light  work. 

3600         ,,  ,,  ,,  healthy  adult  male  during  repose. 

3000         ,,  ,,  „  ,,  ,,     female  ,, 

2000         „  ,,  „  healthy  child  during  repose. 

In  hospitals  the  supply  should  exceed  the  above  estimate  by  one-fourth 
in  ordinary  cases,  and  in  special  cases  it  should  be  doubled. 

On  the  same  assumptions,  in  churches,  lecture-rooms,  and  theatres,  which 
are  only  used  for  a  limited  time,  and  are  initially  filled  with  fresh  air,  respira- 
tion can  go  on  for  some  time  before  the  whole  of  the  air  contained  reaches 
the  limit  of  respirable  impurity,  so  that  the  quantity  of  air  necessary  during 
the  first  hour  is  less  than  that  for  succeeding  hours  ;  the  amount  depends  in 
this  case  upon  the  initial  allowance  of  cubic  space  per  person.  For  an 
average  audience  requiring  8000  cubic  feet  per  hour  each,  for  continuous 
occupation  Dr.  de  Chaumont  calculates  the  following  table  of  the  relation 
between  the  quantity  of  air  required  in  the  first  hour  and  the  initial  cubic 
space : — 

Number  of  cubic  feet 
Cubic  space  in  cubic  of  air  necessary  for 

feet  per  person  ventilation  during  first 

hour  of  occupation ' 

100 2900 

200  2800 

500 2500 

1000 2000 

Every  cubic  foot  of  gas  burned  per  hour  requires  1800  cubic  feet  of  fresh 
air  to  be  supphed  if  the  products  of  combustion  mix  with  the  air  of  the  room. 
One  candle  burning  requires  about  150  cubic  feet  of  air  per  hour,  and  an 
oil  lamp  requires  as  much  as  a  gas  jet  in  respect  of  dilution  of  the  CO2,  but 
frequently  no  allowance  is  made  for  candles  or  lamps.  The  reason  for  this 
is  not  apparent  unless  it  be  that  the  products  of  combustion  of  candles  and 
lamps  are  (under  favourable  circumstances)  without  smell  or  taste  ;  whereas 
a  burning  gas  jet  produces  effects  which  indicate,  without  special  analysis, 
that  the  limit  of  respirable  impurity  has  been  exceeded. 

'  When  the  air  is  drawn  by  a  very  wide  chimney,  60  feet  high,  with  the  temperature  of 
the  air  in  it  212°  F.,  and  the  outside  air  at  32°  F.,  this  estimate  requires  a  clear  orifice  of 
about  7  square  inches  per  person.  This  is  almost  impracticable,  and  consequently  an 
endeavour  should  always  be  made  to  take  advantage  of  the  local  circulation  to  have  the 
occupants  in  the  parts  of  the  room  where  the  air  is  fresher  than  elsewhere. 


WABMING  AND    VENTILATION  117 

2.  The  Quality  of  Air  Beq^oired 

53.  Purity. — It  is  essential  that  the  air  should  be  drawn  from  a  pure 
source,  and  if  necessary  further  purified  before  admission  to  tlie  rooms.  To 
secure  purity  it  should  be  drawn  from  vertical  openings,  preferably  in  a  north 
wall,  from  some  considerable  height  above  the  ground,  free  from  local  con- 
tamination. The  openings  may  be  protected  by  louvres.  The  most  serious 
impurities  of  outside  air  lie  in  the  dust  which  often  contains  the  gsrms  of 
disease.  This  may  be  partially  removed  by  filtering  through  canvas  or  by 
other  means  suggested  in  §  13. 

54.  Temperature. — The  temperature  of  the  air  which  enters  a  room  re- 
quires regulation  according  to  special  circumstances,  and  for  this  purpose  the 
entering  air  should  be  warmed,  and  provision  should  be  made  for  mixing  cold 
fresh  air  with  the  warm  before  entry  into  the  room  in  a  proportion  adjustable 
by  a  register- door,  or  valve. 

The  temperatures  which  should  be  maintained  in  various  buildings  are 
given  by  Morin  '  as  follows  : — 

Schools  .        .        .        .  •      .        .        .        .  15°  C.  59°  F. 

Hospitals 16°-18°  61°-64°-5 

Accident  wards 12°  54° 

Shops,  barracks,  prisons  ....  15°  59° 

Theatres,  assembly-rooms,  lecture-rooms        .  19°-20°  66°-68'^ 

But  it  must  be  remembered  that  no  temperature  will  suit  all  persons  ;  a 
room  that  seems  intolerably  hot  to  a  person  freshly  entering  after  a  brisk 
walk  on  a  cold  day  may  seem  inadequately  warmed  to  those  who  have  been 
•engaged  in  it  for  some  hours  in  sedentary  occupation. 

55.  In  some  instances  the  warming  of  buildings  is  carried  out  entirely  by 
liot  air ;  in  such  cases  the  entering  air  must  be  at  a  temperature  above  the  mean 
temperature  to  allow  for  losses  of  heat  through  windows  and  walls.  Such  a 
plan  does  not  seem  the  most  desirable.  Hot  air  warming  is  often  said  to  be 
dirty.  The  hot  air  moving  over  cold  surfaces  produces  dust  deposits,  though 
this  may  be  an  advantage,  as  it  is  a  means— not  a  very  satisfactory  one — of 
getting  rid  of  the  dust  from  the  air  ;  but  there  are  advantages  in  heating  the 
walls  and  furniture  by  means  of  direct  radiation  and  not  by  hot  air  contact,  for 
this  promotes  circulation  of  air,  even  in  remote  corners,  and  prevents  loss  of 
heat  from  persons  by  radiation  ;  so  that  it  would  seem  advisable  where  such 
a  plan  is  feasible  to  allow  the  air  to  enter  at  a  temperature  of  a  degree  or  so 
helow  that  of  the  room  and  make  up  the  necessary  supply  of  heat  by  open 
fires  or  hot- water  pipes.  There  are  incidental  advantages  m  this  method,  as 
it  reduces  the  local  circulation  which  depends  on  the  differences  of  tempera- 
ture of  air  in  different  parts  of  the  room. 

The  introduction  of  fresh  air  direct  from  the  outside  without  warming  it 
at  all  is  altogether  impracticable  if  draughts  are  objected  to. 

The  details  of  different  arrangements  for  warming  air  will  be  considered 
later.  They  may  be  classified  as  air-stoves,  and  batteries  of  hot  water,  or 
steam  pipes.  It  is  uneconomical  to  carry  heated  air  any  long  distance,  as  the 
amount  of  heat  conveyed  per  cubic  foot  of  air  raised  to  a  given  temperature 
is  so  small  and  so  easily  lost  in  transit.  On  this  account  Morin  considers 
their  availabihty  limited  to  a  horizontal  range  of  12  to  14  metres  (40  to  45 
feet),  measured  horizontally  from  the  heating  apparatus ;  it  is  preferable 
in  a  large  block  of  buildings  to  carry  the  heat  by  means  of  water  pipes  and 
form  local  batteries  of  pipes  whereby  to  heat  the  air  immediately  before  it  is 

>  Manuel  de  Cliauff.  &c.  p.  186. 


118  HYGIENE 

brought  into  use  than  to  have  a  stove  m  the  basement  and  distribute  the- 
heat  by  distributing  the  air  supphed  by  the  stove. 

56.  Vitiation  of  Air  by  Heating  Apparatus. — In  -^-arming  the  air  care 
must  be  taken  to  secure  that  it  is  not  at  the  same  time  vitiated.  It  is  a  matter 
of  common  experience  that  if  air  is  heated  by  being  passed  over  a  red-hot  iron 
pipe  it  becomes  '  burnt '  and  extremely  disagreeable. 

General  Morin  ^  has  investigated  the  cause  of  the  vitiation  produced  by 
iron,  especially  cast  iron,  when  raised  to  a  dull  red  heat.  He  shows  that 
there  is  produced  in  the  air  an  appreciable  quantity  of  carbonic  oxide — a 
highly  poisonous  gas — which  results  when  coal  is  burned  with  insufficient 
oxygen,  or  when  carbon  dioxide  gas  is  passed  over  red-hot  coal  or  coke.  It  is 
to  this  gas  that  the  poisonous  action  of  charcoal  braziers  and  coke  fires  is 
due.  The  presence  of  the  carbonic  oxide  may  be  due  to  four  independent 
causes,  which  may  act  concurrently,  viz, : — 

1.  The  permeabihty  of  the  iron  for  this  gas  at  high  temperatures. 
If  any  carbonic  oxide  is  formed  in  the  stove  some  of  it  will  pass  out  through 
the  red-hot  iron  to  the  external  air. 

2.  The  dh-ect  action  of  the  oxygen  of  the  air  upon  the  carbon  of  the 
cast  iron. 

3.  The  decomposition  of  the  carbon  dioxide  gas  of  the  atmosphere  by  the 
red-hot  metal. 

4.  The  incomplete  combustion  of  organic  dust  floating  in  the  air. 

The  production  of  carbonic  oxide  does  not  take  place  unless  the  iron  is 
red  hot.  The  air  supplied  for  ventilation  should  therefore  never  pass  over 
red-hot  iron  ;  all  iron  parts  of  a  stove  that  are  liable  to  become  heated  to 
redness  should  be  lined  with  fire-brick  or  other  refractory  substance. 

In  such  a  case,  evidently,  no  ventilation  might  be  better  than  supplying 
the  place  of  moderately  foul  air  by  air  rendered  poisonous  by  the  presence  of 
carbonic  oxide,  which  is  deleterious  if  breathed  for  a  considerable  time,  even 
if  in  minute  proportion. 

Moreover,  air  passing  over  highly  heated  surfaces  frequently  acquires 
disagreeable  properties  which  may  be  caused  by  the  action  of  the  heat  upon 
the  dust  of  the  air,  or  that  deposited  upon  the  heating  surfaces.  These 
should  therefore  be  so  placed  that  they  can  be  inspected  and  regularly 
cleaned. 

57.  Humiditij. — When  the  external  temperature  is  low,  the  air  supplied 
will  require  to  be  moistened  as  well  as  warmed.  The  average  humidity  of 
air  in  these  islands  is  about  75  per  cent.,  so  that  the  pressure  of  water 
vapour  in  the  room  must  be  about  three-quarters  of  the  saturation  pressure 
indicated  on  the  diagram  on  p.  46,  or  the  pressure  indicated  by  a  point  half- 
way between  the  corresponding  points  of  the  two  curves  there  plotted.  The 
diagram  will  also  show  what  is  the  maximum  possible  vapour  pressure  in 
the  external  air  at  this  temperature,  and  thus  the  necessity  for  moistening 
can  be  estimated.  Part  of  the  necessary  moisture  will  be  supplied  by  the 
actual  respiration  itself,  but  more  may  be,  required  which  may  be  provided 
by  injecting  clean  steam  or  water  spray,  or  simply  by  exposing  a  w^ater 
surface  to  the  air. 

3.  Positions  of  Inlet  and  Extract  Flues 

58.  The  fundamental  condition  to  be  satisfied  is  that  the  air  which  leaves 
the  room  by  the  extract  flues  should  be,  in  as  far  as  there  is  any  difl'erence, 
the  impure  portion,  as  contrasted  with  the  pure  entering  air. 

The  differences  of  detail  which  the  problems  in  ventilation  present  mak& 
*  Mimoires  de  VAcadimie  des  Sciences,  vol.  xxxviii.     See  Manuel,  &c.  p.  113. 


WABMING  AND   VENTILATION  11& 

it  difficult  to  formulate  any  precise  rules  as  to  where  tlie  air  should  enter 
or  leave  the  room  in  order  that  this  condition  should  be  satisfied,  and 
authorities  differ,  to  a  certain  extent,  on  the  point.  The  main  object  of 
ventilation  would  be  secured  if  the  air  which  has  been  once  respired  were  dis- 
placed in  such  a  way  that  it  cannot  be  again  passed  into  the  lungs,  but  is 
directly  carried  to  the  outlets.  We  cannot,  however,  treat  each  occupant  of 
a  room  like  a  gas  jet,  and  provide  him  with  a  separate  exit  pipe.  The  next 
best  thing  seems,  at  first  sight  at  any  rate,  to  get  the  exit  pipes  as  near  to 
the  source  of  contamination  as  possible,  so  that  the  respired  air  may  be 
forthwith  removed.  This  plan  is  adopted  with  obnoxious  gases  produced  on 
the  table  of  a  chemical  lecture-room.  An  opening  in  the  table  provided 
with  a  strong  down  draught  removes  nearly  all  the  offensive  vapour  in  a 
very  satisfactory  manner,  and  some  similar  plan  may  be  adopted  with  the 
auditory.  The  expired  air  is  driven  out  through  the  nostrils  and  mouth 
with  very  considerable  velocity,  producing  eddies  and  rapid  mixture  with  the 
surrounding  air,  so  that  the  upward  force  acting  on  the  impure  mixture  due 
to  the  increase  of  its  temperature  is  very  small.  The  direction  of  projection 
of  the  air  for  a  person  sitting  or  standing  (with  the  head  in  a  natural 
position  or  inclined  downwards  as  in  writing)  is  downwards,  so  that  by  each 
act  of  expiration  a  person  projects  into  the  room  a  quantity  of  used  air 
which  mixes  with  the  air  of  the  room  somewhat  beneath  his  mouth,  and 
this  mixed  volume,  if  left  in  still  atmosphere,  begins  to  rise  but  very  slowly, 
and  a  very  slight  downward  current  is  sufficient  to  carry  it  further  downward. 
A  number  of  persons  sitting  or  standing  together  will  produce  a  layer  of 
impure  mixture,  and  a  general  downward  movement  of  very  small  velocity 
produced  artificially  will  be  sufficient  to  carry  the  layer  of  mixture  below  the 
heads  of  the  persons,  in  spite  of  the  upward  effect  produced  by  the  natural 
heat  of  the  bodies  ;  so  that  in  the  case  of  a  number  of  persons  on  the  same 
level  the  most  direct  plan  of  carrying  away  the  impure  air  is  to  establish 
a  general  downward  current  by  means  of  outlets  in  or  near  to  the  floor. 
The  total  area  of  these  outlets  must  be  so  great  that  there  is  no  down- 
ward motion  of  the  air  perceptible  as  a  draught  in  their  neighbourhood. 
Similar  considerations  apply  when  the  audience  is  arranged  on  tiers  of  seats, 
as  in  an  amphitheatre.  The  position  of  outlets  thus  indicated  is  suitable 
for  the  cases  of  lecture-halls,  concert-rooms  (of  not  more  than  two  floors), 
schools,  churches,  and  chapels.  The  openings  into  the  extract  flue  may  be 
made  under  the  seats  either  on  the  floor  or  in  the  risers  of  the  seats  at  the 
back,  and  advantage  should  be  taken  of  the  erection  of  desks,  book-rests, 
&c.,  to  avoid  the  inconvenience  of  the  openings  being  so  near  the  feet  as  to 
cause  a  sensation  of  draught.  Moreover,  the  openings  must  be  very  numerous 
and  well  distributed,  and  so  proportioned  in  size  that  each  one  acts  equally. 
The  entry  of  fresh  air  should  be  so  arranged  as  to  prevent  local  circula- 
tion and  selective  circulation,  and  to  be  sufficiently  far  away  from  the 
persons  to  avoid  direct  draughts.  The  most  potent  cause  of  local  circulation 
in  cold  weather  in  churches  and  large  halls  is  the  large  area  of  windoAv 
space,  and  it  would  be  well  to  fix  the  position  of  the  warm  air  uilets  with 
special  reference  to  this  point.  It  would  probably  be  completely  obviated 
by  arranging  a  hot-air  inlet  a  short  distance  under  each  window,  and  this 
position  for  inlets  would  seem  in  most  cases  to  satisfy  the  conditions 
specified.  In  that  case  the  descending  cold  air  would  have  to  be  reckoned — 
partly  at  any  rate — instead  of  fresh  cold  air  taken  from  outside  to  mix  with 
the  warm  air  supplied.  The  cooling  effect  of  windows  can  of  course  be 
reduced,  as  indicated  on  p.  41,  by  double  glazing.  If,  by  that  means  or 
some  other,  the  windows  may  be  left  out  of  account — a  circumstance  of  very 


120  HYGIENE 

rare  occurrence — the  position  of  the  inlets  may  be  dictated  by  consideration 
merely  of  avoiding  draughts  and  selective  circulation.  The  outlets  being  at 
the  floor  level,  the  inlets  should  be  well  above  the  heads  of  the  audience, 
and,  if  slightly  colder  than  the  air  of  the  building,  the  incoming  air  should 
be  directed  upwards,  if  warmer,  horizontally  or  slightly  downwards. 

For  dining  halls  the  case  is  somewhat  dift'erent.  The  heat  of  the  dishes 
and  frequently  of  caudles  on  the  tables  makes  a  much  more  intense  local 
circulation,  and  exit  orifices  in  the  ceiling  should  be  provided  to  meet  the 
case.  These  may  be  in  addition  to  or  instead  of  the  floor  outlets  already 
suggested.  In  considering  the  supply  of  fresh  air,  the  space  over  each  table 
must  now  be  regarded  as  an  upcast  shaft  of  impure  air  which  must  be 
allowed  to  travel  directly  to  the  upper  ventilators  ;  the  inlets  may  be  therefore 
high  up,  in  such  positions  as  to  avoid  these  rising  columns  of  air,  and  in 
the  ventilation  system  for  this  case  we  must  make  use  of  the  local  circulation 
and  not  simply  trust  to  the  motion  of  parallel  horizontal  layers  of  air. 

The  lighting  of  a  room  by  gas  requires  special  treatment.  The  gas 
produces  local  circulation,  and  if  a  separate  extract  flue  is  provided  it  is 
generally  in  a  j)osition  most  unfavourable  for  general  ventilation  ;  the  whole 
air  of  a  large  hall  must  be  very  impure  before  a  central  chandelier  is 
eflective  in  removing  impurity.  Under  low  galleries  the  beneficial  effect  of 
a  gas  jet  with  separate  flue  is  more  direct  provided  that  the  inlets  are  so 
placed  that  selective  circulation  is  avoided.  Under  the  circumstances  it  is 
better  to  make  the  ventilation  independent  of  the  lighting  arrangements, 
and  to  enclose  the  gas  lights,  as  is  done  on  the  Wenliam  gas-light  system 
and  other  regenerative  gas  burners,  so  that  only  as  much  air  is  supplied  to 
the  gas  as  is  required  for  the  combustion  :  this  may  be  drawn  either  from 
the  room  or  separately  from  the  outside. 

In  theatres  the  problem  becomes  unusually  comphcated  in  consequence 
of  the  great  intensity  of  the  local  circulations  from  the  lighting  and  the 
proximity  of  many  corridors  and  rooms,  and  the  necessary  smallness  of  the 
allowance  of  cubic  space  per  head  of  the  audience. 

The  arrangement  proposed  by  Morin^  includes  a  series  of  outlets  in  the 
galleries,  the  boxes,  and  the  floor  of  the  pit,  and  along  the  front  of  the  stage, 
and  inlets  delivering  into  the  area,  between  the  joists  of  the  floor  of  every  tier, 
with  special  outlet  for  the  gas  chandelier. 

The  position  of  inlets  for  hospital  wards  requires  also  special  consideration. 
General  Morin  ('  Manuel,'  p.  ii48)  recommends  them  to  be  placed  at  the  head 
of  the  beds  at  the  floor  level,  but  in  the  side  walls,  allowing  at  least  one  for 
every  two  beds  in  ordinary  wards  and  one  for  every  bed  in  wards  requiring 
special  ventilation.  But  De  Chaumont  (Parkes'  '  Hygieiie,'  p.  186),  on  the 
ground  that  the  breathed  air  rises  rapidly,  not  only  on  account  of  its  tem- 
l^erature  but  from  the  direction  of  projection,  recommends  that  the  point  of 
discharge  for  patients  in  bed  should  be  above,  and  the  fresh  warm  air  supplied 
from  under  the  beds.  In  a  plan  said  to  be  successful  in  America  the  outlets 
are  under  the  beds  and  fresh  air  is  supplied  at  the  bed  head  to  each  patient. 
It  remains  probably  still  a  matter  of  opinion  which  of  these  plans  should  be 
adopted.  The  reasojs  Avhich  we  have  given  for  placing  the  outlet  at  a  low 
level  in  the  case  of  a  lecture-room  or  haU  are  not  strictly  applicable  to 
hospital  wards,  as  the  beds  form  obstacles  to  the  downward  flow,  and  each 
patient  might  cause  a  local  circulation  that  would  interfere  with  the  satis- 
factory working  of  the  plan.  Possibly  outlets  at  middle  height  and  inlets 
both  at  the  top  and  bottom  would  satisfactorily  solve  the  problem. 

'  See  the  diagrams  for  the   Theatre  Lyrique  and  Theatre  de  la  Gait6,  Etudes,  vol.  i. 
lilates  siv.  xv. 


WABMING  AND    VENTILATION 


121 


A 


4.  Provision    of   a    Suitable    Head  for    Extracts    and    Inlets.     Correct 
Numerical  Proportion  hettveen  Areas  of  respective  Inlets  or  Outlets. 

59.  Three  types  of  plan  may  be  considered  : 

1.  Injection  of  air  by  a  blower  from  a  central  air  chamber,  leaving  the 
.air  to  find  its  way  out  of  the  outlets  by  the  secondary  head,  due  to  increase 
of  pressure  in  the  system. 

2.  Suction  by  a  single  main  shaft.  The  outlets  in  this  case  govern  the  head 
for  circulation  of  the  different  rooms,  and  the  air  finds  its  way  through  the  inlets. 

3.  Separate  heads  for  the  different  outlets  which  act  as  upcast  shafts, 
the  head  being  due  to  the  difference  of  temperature  of  the  air  in  the  flues  and 
the  external  air. 

Any  particular  case  then  may  be  a  combination  of  two  or  more  of  these 

three  types.     The  comparative  advantages  of  the  different  methods  will  be 

treated  later.     What  we  now  wish  to  point  out  is  that  in  any  case  one  of  the 

conditions  of  success  is  that  the  head  for  any  orifice,  inlet  or  outlet,  must  be 

satisfactorily  provided,^ 

and  the  areas  of  inlets 

and   outlets   must  not 

be  taken  at  haphazard, 

and  there   must   be  a 

proper  numerical  pro- 
portion   between    the     

•equivalent  areas  of  the     

different     orifices,   the 

rules  for  the  calculation 

of    which     are     given 

above,    §  20.      If    we 

liave  a  main  channel,  A 

(fig.  42),  with  branch 

■channels,  Aj,  A2,  A3; 

A4,  the  resistances  of 

the  channels  must  be  arranged  by  adjusting  the  equivalent  areas  of  the  orifices. 

o,,  02,  03,  04,  so  that  there  is  the  same  head  for  the  flow  required,  between 
the  rooms  into  which  the  orifices  lead  and  the  point  A  ;  otherwise  one  of  the 

<3hannels  will  '  draw '  more  actively  than  the  others.  The  area  of  the  channel 
A  must  also  be  increased  when  a  new  channel  joins  it,  so  that  the  velocity 
of  motion  of  the  air  may  be  kept  nearly  uniform  throughout  its  length,  and, 
further,  when  the  ventilation  is  by  a  number  of  separate  heads,  the  heads 
must  be  equahsed,  or  at  least  sufficiently  nearly  so  to  prevent  one  over- 
powering the  others. 

The  areas  of  inlets  and  outlets  must  also  be  suitably  related  to  each 
other.  The  area  of  one  or  other  of  the  two  is  decided  by  calculation  of 
the  head  required  to  produce  the  given  circulation  in  the  most  economical 
manner.  In  calculating  the  head,  taking  for  example  the  case  of  ventilation 
by  an  open  fire,  account  must  be  taken  of  the  loss  in  consequence  of  the 
friction  of  the  inlets,  and  thence  it  follows  that  the  greater  the  area  of  the 
inlets  the  better,  so  that  the  exact  equality  of  area  of  the  two  is  not  a 
thing  to  be  striven  after  for  its  own  sake.  What  we  mean  by  suitably  pro- 
portioning them  is  that  the  inlets  should  be  sufficiently  large  to  secure  that 

'  It  seems  hardly  necessary  to  state  that  no  efficient  ventilation  can  be  secured  by  any 
number  of  orifices  unless  there  is  an  adequate  head,  but  a  recent  experience  in  a  room 
^ith  an  open  chimney  (without  fire)  and  open  window  leads  one  to  reflect  on  the  improve- 
ment that  might  have  resulted  if  a  head  had  been  established  by  putting  a  paraffin  lamp 
in  the  fireplace. 


Fig.  42, 


122 


HYGIENE 


the  velocity  shall  not  be  too  great.  According  to  Morin  ('  ]\Iannel,'  p.  193),. 
the  velocity  of  efflux  should  be  about  three  feet  a  second,  and  the  velocity 
of  hiflux  two  feet  a  second  for  inlets  pointed  downwards,  and  not  more  than 
three  feet  a  second  if  pointed  upwards  or  horizontally  at  a  height  of  twenty 
feet  above  the  heads  of  the  occupants.  If  this  rule  be  followed  the  inlet  area 
must  be  capable  of  being  one  and  a  half  times  as  great  as  the  outlet. 

5.  Completeness  of  Gircidatlon 
GO.  In  determining  the  plan  of  ventilation  of  a  room  the  whole  building 
must  be  treated  as  one  system,  and  the  plan  of  circulation  drawn  out  for  the 
whole.  It  is  not  sufficient  to  have  a  system  which  is  only  in  working 
order  for  a  room  so  long  as  all  the  doors  are  shut,  if  one  of  the  conditions 
of  the  use  of  the  room  be  that  the  doors  sliall  be  frequently  open.  This 
condition  is  especially  peremptory  in  the  case  of  domestic  houses,  and  it 
practically  amounts  to  requiring  every  outlet  to  be  supplied  with  an  adequate 
inlet,  so  that  there  shall  be  no  head  between  different  rooms.  The  ideal 
arrangement  for  a  large  building  would  be  to  combine  the  '  plenum '  and 
'  vacuum  '  methods  in  such  a  way  that  there  should  be  no  head  between  the 
interior  of  any  one  of  the  rooms  and  the  outside  of  the  building. 

APPAEATUS  FOE,  WAEMING  AND   FOE   COOLING 

61.  Hitherto  we  have  been  deahng  mainly  with  the  principles  of  ventila- 
tion and  have  assumed  that  the  difficulties  in  the  way  were  only  those  whicb 
arose  from  the  unalterable  properties  of  air  and  other  materials  that  we  had  to 
deal  with.  We  have  supposed  heat  to  be  distributed  wherever  it  Avas  required 
and  in  whatever  quantity.  We  have  in  fact  disregarded  the  important  practical 
details  of  the  apparatus  that  must  be  used  for  the  distribution  of  air  or  heat, 
and  questions  of  expense  or  economy  have  not  been  dealt  with.  We  now 
proceed,  however,  to  consider  more  closely  the  practical  side  of  the  matter. 
We  will  deal  first  with  the  production  and  distribution  of  heat,  although  com- 
plete separation  between  warming  and  ventilating  cannot  be  accomphshed. 

62.  Artificial  heat  is  produced,  as  we  have  seen  already  (p.  35),  almost 
entirely  by  combustion.  Different  kinds  of  fuel  differ  considerably  in  the 
amount  of  heat  which  is  developed  by  the  combustion  of  a  given  quantity,  and 
the  prices  of  different  fuels  are  also  widely  different.  We  give  accordingly  a 
table  (after  Morin)  of  the  heat  in  lb.  F.  units  developed  by  the  combustion  of 
1  lb.  of  different  kinds  of  fuel,  and  the  number  of  lb.  F.  units  of  heat  produced 
by  the  combustion  of  the  amount  in  each  case  which  can  be  bought  for  one 
penny  at  ordinary  prices.  It  is  of  course  a  rough  table,  as  the  prices  vary 
considerably  m  different  localities. 

Table  VIII. 


Fuel 

No.  of  lb.  F.  units  of  heat 
produced  by  the  combus- 
tion of  1  lb.  of  fuel 

-□  .       ,  f    ,                  No.  of  lb.  F.  units 
Price  of  fuel                      for  one  penny 

Coal. 
Coke. 
Ppat  (dry) 
Dry  wood . 
Petroleum 
Coal  gas    . 

14,000 
12,600 

9,000 

7,200 
21,000 
675  (per  cu.  ft.) 

20s.  ]-er  ton 

13s.  4fZ.  par  ton 

Id.  per  5  lb.' 

25s.  per  ton 

10^.  per  gallon 

3s.  per  1,000  cu.  ft. 

131,000 
176,000 
45,000 
54,000 
17,220 
18,800 

This  table  shows  the  total  quantity  of  heat  that  is  generated  by  the  com- 
plete combustion  of  the  fuel.  Thus  when  a  gas  jet  or  petroleum  lamp  is  burned 
in  a  room  the  table  gives  us  the  amount  of  heat  supplied,  all  of  which  helps 
to  warm  the  room  in  some  part  or  other.     The  other  fuels  are  now,  however,. 

•  Cambridge  price. 


WASHING  AND   VENTILATION  123 

always  burned  in  stoves,  with  chimneys  for  carrying  away  the  products  of 
combustion,  and  every  pound  of  fuel  requires  for  its  combustion  a  definite 
quantity  of  oxygen  whicli  must  be  provided  by  a  constant  supply  of  air  to 
the  stove.  The  oxygen  that  maintains  the  combustion  takes  with  it  into  the 
fire  the  nitrogen  and  other  constituents  of  the  air,  and  these  constituents 
which  take  no  part  in  the  combustion  have  to  be  removed  with  the  carbon 
dioxide  gas  and  water  vapour  which  are  the  immediate  products  of  the  cliemical 
action.  The  amounts  of  heat  given  in  the  table  are  calculated  on  the  sup- 
position that  the  inert  gases  and  products  of  combustion  leave  the  apparatus 
in  which  they  are  burned  at  the  temperature  at  which  they  entered  it,  so 
that  they  carry  away  none  of  the  heat  which  the  combustion  has  produced. 
But  this  supposition  cannot  be  realised  in  practical  Avorking ;  some  heat  is  re- 
quired to  keep  the  air  in  the  exit  flue  at  a  sufficiently  high  temperature  to 
maintain  steadily  the  requisite  supply  of  air  to  the  fire,  so  that,  so  far  as  the 
heating  of  the  room  or  building  is  concerned,  some  heat  must  always  be  lost. 
With  an  open  fire  about  nine-tenths  of  the  heat  of  combustion  disappear, 
being  carried  away  partly  by  the  heated  products  of  combustion,  partly  by 
heated  air  which  passes  up  the  chimney  without  taking  part  in  the  combus- 
tion, and  partly  by  conduction  through  the  walls,  as  the  fire  is  in  general 
placed  against  the  wall  of  the  room, 

63.  To  save  some  of  the  large  margin  of  90  per  cent,  of  practically  wasted 
fuel  has  been  the  object  of  very  many  inventions.  We  cannot  attempt  to 
enumerate  them,i  i^^^  -^g  j^g^y  classify  them  according  to  the  direction  in 
whicli  they  seek  to  limit  the  loss  of  heat.  If  we  consider  the  action  of  an 
open  fire  it  is  evident  that  there  are  two  ways  in  which  heat  passes  into  the 
room  :  (i)  by  radiation  from  the  heated  surfaces  ;  (ii)  by  conduction  to  the 
sides  of  the  grate,  and  thence  by  convection  of  the  air  in  contact  with  it. 
Now  with  an  ordinary  grate  the  larger  part  of  the  heat  which  gets  to  the 
air  by  the  second  way  is  immediately  carried  up  the  chimney  by  the  rapids 
of  inflow  of  air  to  the  chimney.  It  is,  indeed,  only  the  heated  surface  above 
the  stove-opening  which  helps  in  any  way  (except  by  radiation,  which  for 
the  parts  heated  by  conduction  is  very  small)  to  warm  the  room.  The 
effect  of  an  open  fire  must  therefore  be  referred  to  radiation  alone.  Now 
the  radiation  varies  very  rapidly  with  the  temperature  of  the  radiating 
surface.  The  precise  law  is  not  accurately  known,  but  is  not  ill-represented 
by  assuming  the  quantity  of  heat  radiated  to  be  proportional  to  the  fourth 
power  of  the  temperature  of  the  radiating  surface,  measured  from  459°  below 
the  Fahrenheit  zero.  The  result  of  this  is  that  lowering  the  temperature 
of  a  surface  15°  from  1000°  F.,  or  1*5  per  cent.,  will  diminish  the  radiation 
by  6  per  cent.  Or,  to  give  another  example,  suppose  we  had  a  red-hot  ball 
at  1000°  F.,  and  brought  into  contact  with  it  a  second  cold  ball,  and  imagine 
that  the  heat  of  the 
one  was  instantane- 
ously distributed  be- 
tween the  two,  so 
that  we  had  two 
balls  at  500°  F.  con- 
taining the  same 
quantity  of  heat  be- 
tween   them  as  the  ^ 

one  had  originally  ;  Fip.  43, 

the    radiation   from 

the  huo  together  would  be  -|  of  that  from  the  one  ball  originally.     Thus,  if 

'  An  abstract  of  patents  for  grates  &c.  compiled  by  Mr.  J.  Glaisher  is  included  in  the 
'Beport  of  the  Commission  on  Warming  and  Ventilation  of  DiccUings,  1857. 


IM 


HYGIENE 


VI.BMiiaMir.aai. 


without  altering  the  total  supply  of  heat  we  could  so  concentrate  it  that  the 
temperature  of  the  radiating  surfaces  was  raised  from  500  to  1000,  the 
heating  efi'ect  upon  the  room  would  be  more  than  doubled. 

(a)  The  first 
typical  improve- 
ment in  stoves 
will  therefore  be 
the  provision  for 
increasing  the 
radiation  from 
the  burning  fuel. 
Count  Eumford 
long  ago  gave 
rules  by  which  the 
shape  of  the  stove 
should  be  regu- 
lated, viz.  that 
the  covings  should 
beinclinedat  135° 
to  the  back  of  the 
grate,  and  the 
'  register  '  door  at 
the  mouth  of  the 
flue  inclined  at  the 
same  angle.  In 
this  way  some  of 
the  heat  radiated 
from  the  fuel  is 
reflected  into  the 
room  and  thus  saved.  The  rela- 
tive dimensions  of  the  grate 
are  given  in  fig.  43.  The 
material  of  which  the  stove  is 
made  is  also  of  importance.  We 
have  seen  that  it  is  advisable  in 
order  to  promote  radiation  to  limit 
the  conduction,  or  insulate  the 
heat,  as  much  as  possible.  Refer- 
ring to  the  table  on  p.  37  it  will 
be  seen  that  the  stove  should  on 
this  account  be  made  of  firebrick 
as  far  as  possible,  and  the  amount 
of  metal  reduced  to  a  minimum. 
This  point  has  not  hitherto  been 
much  attended  to  by  inventors, 
but  the  recent  fireplaces  of  Messrs. 
Doulton  (fig.  44)  are  constructed 
entirely  of  fireclay  or  pottery  with 
the  exception  of  a  bar  of  iron  in 
the  front.  Grates  are,  moreover, 
frequently  made  by  simply  fixing 
bars  in  brickwork,  the  sides  of 
the  brickwork  being  inclined  to 
the  back  at  nearly  the  angle  suggested  by  Eumford,  and  their  efficiency  with 
a  bright  fire  is  very  well  recognised  by  common  experience.     Further  im- 


FiG  44. 


Fio 


WABMING  AND   VENTILATION 


125 


provement  is  secured  by  making 
the  back  of  the  grate  of  firebrick 
sloping  forward  to  the  throat  of 
the  chimney. 

G4.  [h)  The  second  type  of  im- 
provement in  open  grates  is  that 
in  which  part  of  the  heat  which 
passes  to  the  sides  of  the  grate 
and  the  flue  is  brought  into  the 
room  by  surrounding  the  stove  by 
an  air  space  with  two  openings 
which  communicate,  one  with  the 
external  air,  and  the  other  with 
the  room.  With  these  stoves  the 
air  which  enters  the  room  to  re- 
place that  drawn  by  the  chimney 
is  warmed  by  the  waste  heat  of 
the  fire,  and  the  communication 
established  with  the  outside  air 
affords  a  satisfactory  inlet  for  ven- 
tilation purposes.  Sir  D.  Galton 
introduced  such  ventilating  stoves 
into  the  soldiers'  rooms  in  bar- 
racks, and  there  are  many  kinds 
now  in  the  market.  The  Doulton 
stove,  above  mentioned,  can  be 
provided  with  an  inlet  for  air 
warmed  by  passing  over  the 
heated  surfaces  round  the  fire. 
This  delivers  the  air  to  the  upper 
part  of  the  room.  Boyd's  Hygi- 
astic  grate  (figs.  45-47)  is  con- 
structed on  this  same  principle, 
but  delivers  the  air  through  an 
opening  just  above  the  fire  under 
the  mantel-shelf.  By  these  de- 
vices about  one-fourth  of  the  waste 
heat  can  be  utilised. 

It  is  important  that  the  air 
which  enters  by  these  ventilating 
stoves  should  not  pass  over  any 
iron  surface  which  is  heated  to  a 
red  heat  for  the  reason  given 
above,  p.  118. 

65.  (c)  The  third  typical  modi- 
fication of  open  grates  refers  to  the 
economy  of  loss  of  heat  by  limit- 
ing the  amount  of  air  carried  up 
the  chimney  without  having  taken 
part  in  the  combustion.  In  order 
to  reduce  the  loss  from  this  cause 
attention  must  be  paid  to  the 
shape  and  size  of  the  chimney, 
for  the  head  will  be  determined. 


126 


HYGIENE 


by  the  temperature  of  the  air  in  the  chimney,  and  the  quantity  of  air  which 
traverses  it  for  a  given  head  will  depend  upon  the  resistance  of  the  shaft  or 
upon  the  area  of  the  equivalent  orifice.  The  relation  is  given  in  §  17.  The 
loss  of  heat  can  be  restricted  by  narrowing  the  chimney  and  its  orifices,  but 
the  removal  of  a  certain  quantity  of  air  is  desirable  for  the  purpose  of  ventila- 
tion, and  if  the  chimney-area  is  too  much  restricted,  it  will  not  carry  away  suffi- 
cient, so  that  the  proper  proportions  of  the  chimney  and  its  openings  are  to  be 
determined  with  a  view  to  the  efliciency  of  the  fire  as  a  ventilating  and  warming 
apparatus  combined.  With  this  in  view  ]iIorin '  recommends  that  the  tempera- 
ture of  the  air  in  the  chimney  should  be  maintained  at  about  45°  F.  above  the 
external  air,  and  the  velocity  of  the  smoke  issuing  from  the  chimney  should 
be  about  10  feet  per  second,  in  order  to  secure  stability  in  the  draught,  and 
that  the  chimney  should  be  capped  with  a  cone-shaped  top — the  area  of  the 
orifice  of  discharge  to  be  one-half  of  that  of  the  chimney  (see  p.  98).  The 
chimney  requires  narrowing  at  the  throat  only  if  it  is  wider  than  necessary ; 
in  that  case  there  is  a  danger  of  local  circulation  in  the  chimney  itself,  and 
consequent  smoking,  which  is  prevented  by  the  increased  velocity  in  the 
narrowed  throat.  The  following  table  gives  the  dimensions  of  the  chimney 
flues  necessary  for  rooms  of  different  sizes  according  to  Morin  : — 

Table  IX. 
Relative  Size  of  Cliimney  Flues  for  different  Rooms 


Cubic  capacity  of 
room  in  cubic  feet 

Volii  me  of  air  to  be  removed 

Area  of  section  of 

Diameter  of  section  of 

by  the  chimney  per  hour 
in  cubic  feet 

rectangular  chimney  flue 
in  square  feet " 

cyliudl-ical  chimney  flue 
in  feet  - 

3,500 

17,500 

•99 

•88 

4,200 

21,000 

1^19 

•98 

5,300 

26,500 

1-48 

1^08 

6,350 

31,750 

1-78 

1^21 

7,750 

38,750 

2^17 

1-31 

9,200 

46,000 

2-57 

1-44 

10,600 

53,000 

2-97 

1-54 

When  ventilating  grates  are  used  General  Morin  recommends  the  fol- 
lowing proportions,  '  Manuel,'  p.  58. 

Table  X. 
Tahle  of  Dimensions  for  Ventilating  Grates  (Morin) 


Cubic  capacity  of  room 
in  cubic  feet 

Vohime  of  air  to  be        1     Area  of  section  of 
supphed  per  hour  in  cubic  1  smoke  flue  in  square 
feet                      1                 feef-' 

Area  of  section  of  flue  for 

the  passage  of  fresh  air  in 

square  feet 

3,500 
4,200 
6,300 
6,350 
7,750 
9,200 
10,600 

17,500 
21,000 
26,500 
31,750 
38,750 
46,000 
53,000 

•54 
•66 
•81 
•97 

1-2 

1-4 

1-6 

1-5 
1-8 
2^3 
2-7 
3-3 
3-9 
4-6 

Close  Stoves 

66.  If  the  fire  is  not  required  to  assist  materially  in  ventilation  as  well  as 
in  warming,  very  great  economy  can  be  secured  in  the  consumption  of  fuel  by 
inclosing  the  fire  in  a  chamber  so  that  the  heat  may  be  communicated  to  the 
walls  of  the  chamber,  and  thence  by  conduction  and  convection  to  the  air  of 


ManiLel  de  Chauff. 


With  a  chimney-pot  of  half  the  area  of  the  shaft. 


WABMING  AND   VENTILATION 


127 


the  room  to  be  heated.  The  air  supplied  to  the  fire  is  Hmitod  to  that  taking 
part  in  the  combustion  by  closing  the  front  of  the  stove,  except  that  part 
which  actually  holds  the  fire,  so  that  any  air  which  passes  in  may  be  com- 
pelled to  pass  over  the  fuel ;  the  stove  stands  out  in  the  room  and  the  pro- 
ducts of  combustion  are  led  away  to  a  flue  by  a  narrow  chimney  of  any  required 
length.  Such  stoves  are  made  of  wrought  iron,  cast  iron,  or  earthenware, 
and  nearly  all  the  heat  which  is  produced  by  the  combustion  is  used  in 
warming  the  air  surrounding  the  stove.  The  rapid  distribution  of  heat  is 
assisted  in  Sylvester's  stove,  which  is  of  iron,  by  attaching  to  it  a  number  of 
parallel  iron  plates. 

Close  stoves  are  sometimes  surrounded  with  an  outer  envelope  of  iron  or 
earthenware,  and  the  heat  of  the  stove  is  then  used  to  warm  the  air  in  the 
space  between  the  two  chambers,  and  the  air  so  heated  is  distributed  as 
required.  The  arrangement  is  then  known  as  a  cockle  stove.  Large  stoves 
on  this  plan  are  often  used  on  the  Continent  for  distributing  warm  air,  and 
are  known  as  caloriferes.  The  air  is  in  many  cases  merely  taken  from  the 
chamber  in  which  the  stove  is  placed,  and  is  liable  to  be  very  impure,  but  a 
connexion  may  be  made  directly  with  the  external  air,  in  which  case  fresh 

Table  XI. 


Name  of  apparatus 

Duty 

Eemarks                                     I 

Ordinary  grates    . 

0-10  to  0-12 

Eemove  air  but  do  not  provide  for  the  j 
introduction  of  fresh  air.    Warming 
healthy. 

Ventilating  grates         . 

0-33  to  0-35 

Eemove  air  and    introduce   fresh   air 
moderately      warmed.        Warming 

Stoves : 

healthy. 

Earthenware  for  wood  stove 

•87 

\ 

Gurney : 

Cast  iron  with  i  coal 
flanges       .  ^eoke 

•90 

•85 

Wrought  iron{^^^f^         ; 

•90 

•87 

Cast  iron,  with  downward 

y  Do  not  remove  enough  air  for  healthy 
warming. 

draught — c  ,ke 

•94 

E6n6  Duvoir : 

Cast  iron— coal 

■86 

Compagnie    d'Eclairage    au 

gaz,  without  ventilation    . 

•96 

Fireclay        .... 
Mean 

•93 

/ 

•89 

Cast    iron    —    Compagnie 

d'Eclairage  au  gaz,   with 

ventilation 

•85 

Eeplace   enough   air  for   four  or  five 

Caloriferes,      with  fhori- 
circulation  flues  -  zontal  . 
for  smoke          .   [, vertical 

persons. 
Carmot  produce  directly  sufficient  re- 

•63 

moval  of  vitiated  air,   and   supply 

•80 

generally  air  too  much  heated,  but 

could  easily  be  modified  to  give  air 

at  90°-120°  F.     Warming  unhealthy 

.With      nume- 

when   not    combined  with  ventila- 

rous coils  of 

tion. 

large        area 

compared  with 

Hot  -  water  J  the  boiler 

•65  to  -75 

\ 

apparatus  S  When  all  the 

i  pipes  &c.  are 

Suitable  for    establishing    a    regular 

1  contained   in 

system  of  ventilation. 

!   the  rooms  to 

*   be  heated 

•85  to  ^95 

' 

128  HYGIENE 

air  is  supplied  ;  but  if  the  stoves  are  of  iron  the  air  is  very  frequently  '  burnt ' 
by  passing  over  the  red-hot  iron  surfaces,  and  the  supply  of  fresh  air  by  a 
stove  of  this  form  is  therefore  not  satisfactory. 

Moreover,  according  to  Hood,'  some  of  the  close  stoves  are  liable  to 
develop  explosive  mixtures  of  gases  and  thereby  originate  fires.  Fires  have 
also  arisen  from  the  overheating  of  the  flues,  so  that  close  stoves  require  to 
be  worked  with  very  great  caution. 

Table  XI.  of  the  preceding  page  gives  a  collective  view  of  the  efficiency 
or  duty  of  the  different  kinds  of  stove  investigated  by  General  Morin  and 
is  taken  froni  his  '  Manuel,'  p.  169.  The  numbers  in  the  second  column 
indicate  the  fraction  of  the  total  heat  of  combustion  that  is  applied  to 
warming. 

Gas  Fiees  and  Gas  Stoves 

67.  For  general  convenience  there  can  be  no  question  that  the  most  suit- 
able fuel  is  coal-gas.  It  can  be  ignited  at  any  moment,  the  amount  of  heat 
pioduced  can  be  adjusted  to  the  amount  required,  it  produces  no  dusty 
ashes,  and  can  be  very  easily  accommodated  in  any  position.  These  ad- 
vantages are  enormous  and  will  no  doubt  be  more  appreciated  as  the  con- 
struction of  gas  fires  is  improved.  Against  them  have  to  be  set  the  dis- 
advantages of  the  high  cost  of  the  heat  derived  from  gas — about  eight  times 
that  of  the  same  quantity  from  coal — and  the  want  of  a  cheerful  appearance. 
Its  efficiency  as  a  ventilating  extract  flue  is  the  same  as  that  of  a  coal  fire 
producing  the  same  amount  of  heat.  The  cost  of  gas  compared  with  that 
of  coal  is  probably  not  yet  at  its  lowest  level,  and  may  be  expected  to  be 
lower  when  the  producers  feel  the  competition  of  the  electric  light.  The 
objection  to  gas  fires  on  the  score  of  appearance  can  probably  be  con- 
siderably reduced  by  improvement  in  the  designs  of  the  apparatus.  And 
from  the  circumstance  that  the  appearance  of  a  coal  fire  is  due  to  red- 
hot  surfaces  and  the  flames  of  crude  coal  gas  it  seems  that,  with  a  com- 
bustible that  will  supply  any  required  amount  of  heat  and  any  required 
amount  of  light,  some  arrangement  will  be  possible  that  is  satisfactory, 
unless  it  be  the  very  capriciousness  of  a  coal  fire  that  constitutes  its  main 
attraction. 

In  many  gas  stoves  the  necessity  for  keeping  the  radiation  at  a  maximum 
by  having  only  highly  heated  surfaces  exposed  to  the  room  is  not  sufficiently 
recognised.  They  consist  of  a  large  mass  of  asbestos  nodules  heated  through- 
out by  the  gas,  giving  a  large  body  of  heated  matter  with  its  exterior  surface, 
from  which  the  radiation  mainly  proceeds,  comparatively  cool.  In  such  a 
case  a  larger  fraction  of  the  heat  goes  up  the  chimney  than  with  a  coal  fire 
in  good  condition,  and  the  contact  of  thick  iron  bars  of  an  ordinary  grate 
with  the  heated  asbestos  helps  to  depress  the  efficiency  for  radiation  for  the 
reason  pointed  out  above  (§  63.)  Gas  fires  should  therefore  be  arranged 
so  as  to  concentrate  the  heat  upon  as  small  a  surface  as  possible,  thus 
raising  the  temperature  of  the  surface  to  the  highest  possible  point.  Some 
of  the  more  recent  gas  stoves  embody  this  principle,  as  the  flame  plays  upon 
shreds  of  asbestos  projecting  from  a  fireclay  back.  Wright's  stove  is  an 
example  of  this.  It  is  arranged  so  that  the  heated  products  of  combustion 
also  pass  over  a  series  of  tubes  communicating  with  the  outside  air,  and  thus 
provides  for  a  supply  of  warmed  fresh  air.  The  same  arrangement  is  also 
provided  in  some  of  Fletcher's  recent  stoves,  one  of  which  is  represented  in 
fig.  48.     George's  Calorigen  is  another  example. 

'  On  Warming  Bidldings  by  Hot  Watej-  &c.  p.  306. 


WABMING  AND   VENTILATION 


129 


'With  gas  stoves  as  with  coal  stoves  economy  of  heat  is  secured  by  arranging 
the  apparatus  so  that  it  stands  out  in  the  room,  and  still  further  by  limiting 
the  size  of  the  chimney  flue  and  combustion  area  ;  but  this  economy  is  at  the 
sacrifice  of  efficiency  as  a  ventilating  apparatus. 
As  a  general  rule  all  gas  stoves  should  be  provided 
with  an  outlet  flue  for  the  escape  of  the  products 
of  combustion,  which  include,  besides  water  vapour, 
carbon  dioxide  gas  and  a  certain  amount  of  sul- 
phur dioxide  gas  due  to  the  combustion  of  the 
carbon  bisulphide  which  occurs  as  an  impurity 
in  coal  gas.  Of  these  products  of  combustion  the 
last  two  seriously  vitiate  the  air  of  the  room,  and 
the  sulphur  dioxide  renders  the  air  not  only  un- 
healthy, but  perceptibly  unpleasant  by  the  sulphur- 
ous taste.  The  effect  upon  plants  is  very  marked 
and  very  destructive,  and  traces  of  it  can  readily 
be  found  in  leather  bookbindings,  which  are 
rapidly  destroyed,  and  brass  work,  which  is  rapidly 
blackened.  Stoves  have  therefore  been  designed  by 
which  the  most  deleterious  product  is  absorbed  by 
water,  or  by  the  iron  or  zinc  lining  of  tubes  through 
which  the  products  of  combustion  are  led.  The 
temperature  of  the  burned  gases  is  very  much 
reduced  by  the  same  arrangement,  so  that  a  large 
part  of  the  water  vapour  is  condensed.  Such 
stoves  are  therefore  used  for  warming  rooms  with 

out  being  provided  with  an  exit  flue,  and  the  whole  of  the  heat  produced  is 
retained  in  the  room.  It  must,  however,  be  borne  in  mind  that  the  carbon 
dioxide  produced  by  the  combustion  is  not  removed,  so  that  the  room  should 
be  well  ventilated,  otherwise  it  rapidly  becomes  unwholesome.  In  fact,  such 
stoves  are  really  only  suitable  for  warming  passages,  lobbies,  and  other  places 
where  there  is  a  considerable  casual  renewal  of  air,  and  persons  do  not  remain 
for  any  length  of  time. 

Some  years  ago  Sir  W.  Siemens  described  in '  Nature  '  an  arrangement  for 
using  coke  ignited  by  gas  in  an  ordinary  grate  in  an  exceptionally  economical 
manner.  Such  a  plan,  which  is  intermediate  between  a  coal  fire  and  a  gas 
fire,  has  considerable  advantages. 

Atmospheric  Burners 

68.  The  gas  which  is  burned  in  stoves  is  now  usually  supphed  through  what 
we  know  as  atmospheric  burners,  which  may  be  either  horizontal  or  vertical, 
the  principle  of  which,  the  same  as  that  of  the  ordinary  Bunsen  burner  of 
the  laboratory,  is  exhibited  in  fig.  49.     The  gas  passes  from  the  supply  pipe 


i'lG.  48 


C 


A 


Fig.  49. 


through  a  nozzle  into  a  small  chamber  provided  mth  perforations  a,  a, 
behind  the  nozzle,  through  which  air  passes  ;  the  air  and  gas  mix  in  the 
comparatively  wide  tube  A,  from  which  the  jets  of  gas  pass  by  orifices  o, 

VOL.   I.  K 


130  HYGIENE 

and  are  there  ignited.  If  the  supply  of  air  is  sufficient  a  flame  which  ia 
iion-luminous,  or  shows  faintly  blue,  is  produced  ;  it  gives  rise  to  no  smoke, 
and  is  much  hotter  than  the  ordinary  illuminating  flame  of  a  gas  jet  in  con- 
sequence of  the  more  complete  combustion  of  the  gas,  but  it  is  liable  to  one 
serious  drawback.  If  the  supply  of  gas  be  too  small  the  tube  A  becomes 
filled  with  an  inflammable  mixture  of  gas  and  air,  which  ignites,  and  the  gas 
burns  thenceforward  at  the  nozzle  n,  producing  an  intolerable  and  easily  re- 
cognised odour  of  half-burned  gas,  due  to  the  hydi-ocarbons  produced  by  the 
incomplete  combustion.  The  gas  will  still  burn  at  the  orifice  o,  but  with  a 
languid,  feebly  luminous,  and  smoky  flame,  instead  of  the  brisk  blue  non- 
luminous  flame  of  the  Bunsen  burner  in  good  condition.  This  '  burning 
down  '  always  occurs  if  the  gas  supply  is  turned  too  low  down,  so  that  gas 
flreswith  atmospheric  burners  cannot  be  turned  down  to  an  unlimited  extent. 
A  reduction  of  the  heat  is  generally  better  provided  for  by  limiting  the 
number  of  jets  rather  than  the  volume  of  any  one  jet.  The  '  burning  down ' 
iilso  occurs  if  the  pressure  of  the  gas  supply  is  too  small  or  if  the  orifices  be  too 
large  ;  the  instability  which  accompanies  this  case  is  easily  recognised  by  the 
roaring  of  the  jets  and  the  very  marked  cone  of  blue  luminosity  in  the  in- 
terior of  the  jet  close  to  the  orifice.  When  the  flame  is  thus  unstable  the 
burning  down  occurs  when  the  gas  is  exposed  to  a  sudden  draught.  Any 
noticeable  smell  of  half-burned  gas  from  a  gas  fire  should  at  once  be  met  by 
an  examination  of  the  state  of  the  jet.  In  order  to  set  it  right  if  it  be  burn- 
ing at  the  nozzle  the  gas  must  be  turned  off  completely  and  re-ignited  at  the 
proper  opening. 

Atmospheric  burners  are  now  made  with  devices  for  preventing  the 
*  lighting-back.'  One  of  the  devices  is  to  cover  the  openings  at  wlaich  the 
gas  burns  with  wire  gauze. 

69.  The  volume  of  air  drawn  out  of  a  room  by  a  chimney  is,  according  to 
Morin,  3200  to  4000  cubic  feet  per  pound  of  coal  burned  with  a  chimney  of 
average  height  (50  to  55  feet),  and  the  volume  required  for  combustion  is  IGO 
to  200  cubic  feet.  If  gas  is  used  for  ventilation  the  relation  between  the 
amount  of  gas  burned  and  the  volume  of  air  removed  is  given  in  the  following 
table,  taken  from  Morin,  p.  198  : — 

Table  XII. 
Volume  of  gas  Volume  of  air 

consumed  per  hour  passing  up  the  flue 

in  cubic  feet  per  cubic  foot  of  gas  biu'iied 

71 1900  cu.  ft. 

14-1 1400     „ 

28-2 700     „ 

35-3 600    „ 

42-3 500     „ 

49-3 450     „ 

The  gas  was  burned  in  a  chimney  about  a  foot  wide.  The  table  shows 
that  the  distribution  of  heat  over  a  wide  area  is  more  effective  for  ventilation, 
and  hence,  for  example,  it  would  be  better  to  double  the  area  of  section  of  a 
■chimney  and  have  two  separate  gas  jets,  than  to  combine  the  two  jets  into 
one,  and  so  double  the  consumption  of  gas  in  the  same  chimney. 

70.  When  it  is  proposed  to  warm  a  building  by  means  of  hot  air  provision 
must  be  made  for  maintaining  a  sufiicient  flow.  The  heated  air  naturally 
rises  and  may  itself  maintain  the  flow,  if  the  room  to  be  warmed  be  above  the 
hot-water  pipes  or  hot-air  stove,  and  be  provided  with  extract  flues  into  which 
the  warmed  air  ultimately  passes.  The  supply  of  warm  air  can  be  more 
easily  controlled  if  the  extract  flues  are  furnished  with  an  independent  supply 


WABMING  AND   VENTILATION  131 

of  heat,  as  by  means  of  gas  jets  burning  in  them,  or  by  using  as  extract  flues 
the  chimneys  of  open  fireplaces  with  small  fires  not  themselves  sufficient  for 
the  satisfactory  heating  of  the  room.  In  such  cases  the  total  supply  of  air  to 
the  room  is  governed  by  the  draught  of  the  extract  flues,  and  warmed  air,  or 
cold,  can  be  supplied  by  suitable  arrangements  as  occasion  may  require.  If 
we  take  the  case  of  an  ordinary  house  we  may  regard  each  fire  as  requiring 
about  15,000  cubic  feet  per  hour,  usually  supplied  through  casual  oriiices 
direct  from  the  outside  air,  but,  if  a  special  fresh  air  inlet  be  furnished,  ter- 
minating in  a  case  of  water  pipes  in  the  hall,  the  air  supply  to  the  fires  will 
be  drawn  in  great  part  from  this  inlet,  and  the  whole  house  will  in  this  way 
be  continuously  supplied  with  moderately  warmed  air.  It  need  not  be  sup- 
posed that  the  heat  thus  communicated  to  the  entering  air  passes  directly 
into  the  rooms  where  the  fires  are ;  on  the  contrary,  the  heated  air  causes  a 
very  vigorous  local  circulation  up  and  down  stairs  and  makes  an  extensive 
tour  of  the  house  before  reaching  the  chimney  by  which  it  escapes  again  to 
the  outside.  I  have  found  a  fresh-air  inlet  such  as  here  described  delivering 
22,000  cubic  feet  of  air  per  hour  into  a  house  to  feed  fires  in  three  rooms. 
It  need  scarcely  be  remarked  that  in  warming  by  hot  air  the  object  aimed  at 
should  be  to  supply  a  large  quantity  of  moderately  warmed  air  and  not  a 
small  quantity  at  a  comparatively  high  temperature.  Some  systems  of  hot- 
air  warming  are  very  defective  from  this  point  of  view.  Instead  of  providing 
•active  extract  shafts,  the  air  may  be  driven  over  the  heating  coils  by  means 
of  a  fan  if  satisfactory  arrangements  can  be  made  for  driving  it. 


On  the  Distribution  of  Heat 

71.  "We  have  been  considering  in  the  preceding  paragraphs  the  various 
ways  of  producing  heat  and  the  economy  of  production ;  the  next  question 
to  be  considered  is  the  method  of  carrying  the  heat  from  one  central  furnace 
to  rooms  more  or  less  distant  from  the  furnace.  The  different  plans  which 
have  been  tried  may  be  enumerated  as  distribution  by  circulation  of  hot  air, 
^ater  at  low  pressure,  water  at  high  pressure,  and  steam,  respectively. 

Distribution  by  Hot  Air 

72.  This  system  is  frequently  employed  with  caloriferes  or  cockle  stoves. 
Tubes  are  carried  from  the  air  chamber  surrounding  the  furnace ;  the 
■circulation  is  maintained  by  the  head,  due  to  the  difference  between  the  tem- 
perature of  the  air  in  the  delivery  flues  and  tbat  of  the  air  as  it  enters  the 
supply  inlet  of  the  stove.  It  follows  that  the  furnace  must  be  at  the  bottom  of 
the  system  for  the  supply  of  hot  air.  The  laws  which  govern  the  circulation 
•of  air  in  the  flues  have  been  given  (§§  14-21).  The  amount  of  heat  which  a 
given  quantity  of  air  carries  is  very  small,  so  that  it  must  be  raised  to  a  very 
high  temperature  if  any  considerable  distance  has  to  be  traversed,  and  the 
loss  in  transit  is  very  large  ;  it  is  therefore  only  a  suitable  method  for  local  dis- 
tribution.^ The  heat  for  a  large  hall  or  series  of  rooms,  for  example,  should  be 
carried  by  water  to  a  battery  of  hot-water  pipes  in  a  hot-air  chamber  near  the 
rooms,  and  the  distribution  of  the  heat  from  the  battery  of  pipes  effected  by  air 
passing  from  the  hot-air  chamber  through  comparatively  short  channels  to 
the  inlets  of  the  rooms.  Care  must  be  exercised  in  forming  the  channels  to 
be  used  for  hot  air,  as  they  are  liable  to  warp  and  crack  in  consequence  of 
the  drying  effect. 

»  See  p.  117. 

k2 


132 


HYGIENE 


Distribution  by  Water  at  Low  Pressiire 

73.  This  method  is  one  which  is  very  frequently  employed  for  distributing^ 
heat  in  large  buildings.  The  distribution  is  effected  by  the  circulation  of 
water  in  metal  pipes — generally  cast  iron — one  part  of  the  circulation  system 
being  a  boiler  which  is  kept  at  a  high  temperature  by  a  furnace.  Represent- 
ing the  circulation  diagrammatically  (fig.  50),  we  may  regard  it  as  consisting  of 
two  vertical  tubes  HB,  H'L  connected  at  the  top  by  a  horizontal  tube  HH'. 
The  bottom  end,  L,  of  the  vertical  tube  H'L  is  connected  with  the  bottom 
of  a  boiler  at  L',  and  from  the  top  of  the  boiler  a  tube,  BH,  passes.  At  the 
highest  point  of  the  circulation  is  an  air- vent,  A,  open  to  the  atmosphere,  so 
that  the  pressure  at  any  point  of  the  circulation  exceeds  the  atmospheric 
pressure  only  by  the  pressure  due  to  a  column  of  water  whose  height  i& 
equal  to  the  vertical  distance  between  the  point  A  and  the  point  at  which 
the  pressure  is  required.  Thus  the  pressure  in  the  boiler  will  increase 
by  '43  lb.  per  square  inch  for  every  foot  of  vertical  height  of  the  circulation 


^r 


Q' 


Fig.  50. 


above  the  boiler.  If  we  take  the  extreme  case  of  a  cu-culation  100  feet  high 
the  pressure  in  the  boiler  will  exceed  the  atmospheric  pressure  by  43  lb.  per 
square  inch.  Now  the  temperature  of  water  cannot  exceed  a  certain  point, 
depending  on  the  pressure,  without  producing  steam  ;  the  temperature  for  a 
pressure  of  43  lb.  in  excess  of  the  atmospheric  pressure  is  290°  F.,  or  only 
78°  above  the  ordinary  boihng-point.  If  the  temperature  in  the  boiler 
exceeded  this,  when  it  was  supplying  a  circulation  100  feet  high,  steam  would 
be  formed,  which  would  pass  up  the  vertical  pipe  and  condense  with  con- 
siderable noise  and  tumult  in  the  cooler  water  until  it  had  heated  the  whole 
upper  part  of  the  circulation  sufficiently  for  it  to  escape  as  steam  at  A. 
This  formation  of  steam  in  hot-water  pipes  is  not  allowable,  so  that  the 
furnace  must  not  be  stoked  so  as  to  heat  the  water  in  the  boiler  to  that 
temperature.  And  hence  the  highest  temperatures  possible  in  a  circulation 
open  to  the  air  at  one  point,  is  212°  at  the  top,  and  increasing  (not, 
however,  proportionately  to  the  depth)  until  at  a  depth  of  100  feet  below  the 


WABMING  AND   VENTILATION  133 

top  it  may  possibly  reach  290°  F.  As  100  feet  would  be  a  very  exceptional 
height,  we  may  say  that  the  temperature  of  water  in  low-pressure  circulation 
will  not  generally  exceed  212°.  This  is  the  characteristic  which  distinguishes 
it  from  the  high-pressure  water  system. 

It  is  essential  that  the  circuit  of  water  should  be  complete  ;  an  accumula- 
tion of  air  in  the  pipe  entirely  stops  the  flow,  so  that  a  vent  for  air  must  bo 
provided  at  the  top,  and  wherever  air  would  naturally  be  imprisoned  when  the 
pipes  are  filled  with  water  from  the  top.  Water,  on  being  heated,  disengages 
a  very  large  quantity  of  dissolved  air,  so  that  these  air- vents  will  always  be 
required  to  be  open  from  time  to  time  when  the  pipes  have  been  filled  with 
fresh  water  after  being  emptied.  It  is  moreover  necessary  to  provide  for  the 
•expansion  of  the  water,  so  that  it  is  usual  to  place  at  the  top  of  the  system  of 
pipes  a  small  cistern,  C,  into  which  the  water  driven  out  by  the  expansion 
-can  pass  without  causing  an  overflow ;  and  the  same  cistern  may  be  employed 
to  fill  the  pipes  and  automatically  replace  the  water  lost  by  leakage  if  it 
be  provided  with  a  water  supply  and  ball-tap.  Of  the  two  pipes  connected 
with  the  boiler,  BH  is  called  the  flow-pipe  and  LL'  the  return-pipe. 

74.  The  calculation  of  the  flow  of  water  in  the  circulation  is  very  similar 
to  that  of  air  already  considered.  The  head  is  due  to  difference  of  density  of 
hot  and  cold  water,  and  may  be  calculated  as  follows.  Consider  the  two  portions 
of  the  two  vertical  tubes  contained  between  two  horizontal  planes,  Ac,  h'c', 
•one  foot  apart ;  let  p  be  the  density  of  water  between  h  and  hJ,  p'  that  be- 
tween c  and  c' ;  the  pressure  due  to  the  height  hh'  is  {hh')p  lb.  weight  per 
square  foot,  and  that  due  to  cc'  is  (cc')p'  lb.  weight  per  square  foot,  and  the 
difference  of  pressure  for  that  foot  of  the  vertical  height  of  the  circulation  is 

{ccy  -  {hh')p, 

and  the  work  done  by  the  difference  of  pressure  for  the  passage  of  V  cubic 
■feet 

■      Y{icc')p'-{hh')p}. 

The  head  is  therefore  {  [cc')  p'  —  (hh')  p  }po,  where  pq  is  the  standard  density 
at  the  freezing-point.  But  p'  =  po  (1  —  «^')  and  p=  p^  (1  —  at),  where  a  is 
the  coefficient  of  expansion  of  water.^  Hence  the  head  for  one  foot  =  a{t  —  t') 
(since  cd  and  hh'  are  each  equal  to  one  foot),  or  the  head  per  foot  per  unit  differ- 
•ence  of  temperature  is  equal  to  a. 

Hence,  to  find  the  head  for  any  circulation,  we  may  divide  the  circulation 
into  foot  sections  by  parallel  horizontal  planes  one  foot  apart.  Measure  the 
temperature  at  each  section  of  the  flow  and  return-pipes,  and  the  head  of 
the  whole  circulation  is  the  sum  of  the  differences  of  temperature  of  cor- 
responding sections  multiplied  by  the  coefficient  of  expansion  of  water.  If 
the  total  sum  of  the  differences  of  temperature  comes  out  negative  it  shows 
that  the  circulation  is  in  the  opposite  direction. 

The  temperature  at  different  points  of  the  circulation  may  be  approximately 
determined  by  placing  a  thermometer  on  the  pipe  and  wrapping  it  round 
with  a  good  thickness  of  cloth  or  felt. 

1  For  the  sake  of  simplicity  -we  have  assumed  that  the  coeflficient  of  expansion  of 
water  is  the  same  at  all  temperatures.  This  is  not  really  the  case.  In  fact,  -water 
contracts  slightly  when  it  is  heated  for  the  range  of  temperature  between  32°  P.  and 
.39°  F.,  and  on  further  heating  it  expands,  at  first  very  slightly  and  then  to  a  gradually 
increasing  extent,  until  the  expansion  of  a  cubic  foot  for  the  ten  degrees  below  the  boiling- 
point  is  -0042  cu.  ft.  The  temperatures  in  the  flow  and  return  pipes  of  a  hot-water 
circulation  will  not  be  far  outside  the  limits  of  92°  F.  and  212° F.,  and  the  mean  coefficient 
of  expansion  for  this  range  is  -000318,  which  may  be  taken  as  the  numerical  value  of  o  in 
'the  expressions  in  the  text. 


134 


HYGIENE 


The  head  depends  upon  the  vertical  height,  so  that  an  incHned  pipe  with 
a  gentle  slope  or  a  coil  of  horizontal  pipes  is  only  e£fective  to  the  extent  of 
its  vertical  height. 

If  the  horizontal  planes  cut  the  pipes  in  more  than  two  points,  as  in 
fig.  51,  at  A,,  7io,  h^,  h^,  the  head  may  be  calculated  as  before,  separately  for 
the  two  portions  A,  and  ho,  and  /13  and  /14  respectively,  so  that  the  head  due 
to  the  section  represented  will  be,  if  ti,  t.y,  t-^,   t^  be  the   corresponding 

temperatures, 

{t\  —  ^2  +  *3  —  ^.i)  «. 


A,     I,  h, from  which  it  will  be  seen  that  the 

introduction  of  a  depression  such  as 
that  represented  in  the  figure  re- 
duces the  head  by  the  sum  of  the 
products  (^2  —  ^3)  «  for  each  vertical 
foot  of  height  of  the  depression 
introduced. 

The  calculation  of  the  head  in 
this  manner  will  make  it  easy  to 
see  from  a  diagram  of  the  proposed 
position  of  water-pipes  whether 
there  will  be  a  flow,  and  in  what 
direction,  and  will  suggest  the  most 
jijQ  51  advantageous  way  of  arranging  the 

pipes  so  as  to  produce  the  maximmn 
head.  Thus,  in  carrying  a  circulation  below  the  boiler,  as  shown  in  fig.  52, 
it  will  be  seen  that  the  head  due  to  the  part  of  the  circuit  above  the  hori- 
zontal line,  lih',  is  opposed  by  that  due  to  the  rest  of  the  circuit,  so  that  if 
the  fall  of  temperature  were  simply  proportional  to  the  length  of  the  pipe 
traversed  the  circulation  in  the  circuit  represented  would  be  reversed.  But 
if  it  be  arranged  so  that  there  is  a  considerable  loss  of  heat  from  HH'  and 

consequent  fall  of  temperature 
'"*  between  H  and  H',  and  if  the 
heat  required  be  taken  from 
coils  on  the  part  of  the  circu- 
lation represented  by  HL,  and 
as  little  as  possible  from  the 
part  leading  from  L  back  to 
the  boiler  (indeed,  Uie  pipes 
may  be  so  arranged  that  part 
of  the  heat  lost  from  h'Jj 
warms  L'A,  by  passing  L7i 
through  the  heating  coil  on 
H'L),  the  circulation  may  be 
established,  though  carrying 
Fig.  52.  pipes  below  the  boiler  is  not 

always  a  successful  arrange- 
ment ;  -and  in  order  to  secure  a  flow  it  may  be  necessary  to  waste  a  good  deal 
of  the  heat  in  cooling  the  part  represented  by  HH'. 

Wherever  there  is  a  head,  great  or  small,  there  will  be  a  flow  of  some 
sort,  provided  there  is  a  continuous  channel  filled  with  water  from  the 
boiler,  and  back  again.  The  magnitude  of  the  flow  as  measured,  say,  in 
cubic  feet  of  water  per  minute  depends,  just  as  in  the  case  of  air,  not  only 
upon  the  head,  but   upon  the  resistance  of  the  complete  chamiel.      The 


WABMING  AND   VENTILATION  135> 

resistance  could  be  calculated  by  laws  similar  to  those  we  have  explained 
for  air,  but  the  calculation  for  any  hot-water  system  would  be  exceedingly 
elaborate  and  complicated,  so  that  hot-water  engineers  work  empirically^ 
from  established  successes  to  any  new  arrangement  required. 

75.  Difficulties  sometimes  arise  when  a  number  of  circulations  have 
to  be  maintained  by  the  same  boiler,  for  if  the  circulations  supply  pipes  on 
different  levels  the  head  for  each  circulation  will  be  different,  and  the  object 
desired  is  that  the  flow  shall  be  the  same  for  each  ;  but  this  can  be  adjusted 
by  means  of  a  valve  upon  each  separate  circulation  by  which  the  circulation 
with  a  greater  head  can  be  '  throttled  ' — that  is,  have  its  resistance  artificially 
increased.  The  plan  is,  however,  not  without  its  disadvantages,  for  it  of 
course  implies  reducing  all  the  flows  to  that  in  the  circulation  with  the 
worst  head.  It  is  therefore  desirable,  if  it  be  seen  that  the  head  for  any 
circulation  will  be  small,  to  make  its  resistance  comparatively  small  also,  so^ 
that  the  other  circulations  need  not  be  throttled. 

High-Pressure  Water  System 

76.  We  have  seen  that  if  one  part  of  a  circulation  have  free  access  to  the 
air  the  temperature  of  the  water  cannot  rise  much  beyond  the  boiling-point 
at  ordinary  pressure,  viz.  212°  F.  But  if  the  water  be  completely  inclosed  the 
temperature  can  be  raised  to  a  very  much  higher  figure,  and  the  pressure 
exerted  upon  the  pipes  is  more  than  proportionately  high.  Thus  the  pressure 
of  steam,  or  the  pressure  required  to  prevent  steam  forming  at  212°  F.,  is 
14|  lb.  per  square  inch,  at  300°  F.  it  is  67  lb.  per  square  inch,  and  at  400°  F, 
250  lb.  per  square  inch. 

A  system  of  heating  by  water  pipes  has  been  designed  and  worked  by 
Messrs.  Perkins  in  which  the  pipes  are  of  wrought  iron  and  sufficiently 
strong  (internal  diameter  f  inch,  external  IfV  inch)  to  withstand  the  pressure 
corresponding  to  very  high  temperatures. 

A  sufficient  length  of  these  narrow  iron  pipes  connected  by  an  ingenious 
device  is  formed  into  a  complete  circuit ;  part  of  the  circuit  is  coiled  into  a 
hollow  coil  and  exposed  to  the  heat  of  a  furnace.  At  the  top  of  the  circu- 
lation is  a  series  of  tubes  of  larger  diameter,  called  expansion  tubes,  half 
filled  only  with  the  water,  the  other  half  with  air,  and  therefore  allowing  for 
the  expansion  of  the  water.  '  When  the  pipes  have  been  filled  with  water  the 
openings  at  the  top  are  closed  by  screw  plugs,  so  that  the  whole  system  forms 
a  closed  vessel  with  a  small  quantity  of  air  at  the  top,  which  does  not, 
however,  extend  so  far  as  to  impede  the  circulation  of  the  water.  The  water 
circulates  with  very  great  rapidity  in  spite  of  the  narrowness  of  the  bore,  and 
when  the  apparatus  is  in  full  working  the  temperature  of  the  pipes  reaches,  as 
a  rule,  300°  F. 

The  temperature  is  regulated  by  fixing  the  proportion  of  length  of  pipe  in 
the  furnace  to  the  length  outside  ;  it  is  usually  one-tenth.  If  the  space  to 
be  warmed  is  too  large  to  be  heated  properly  by  a  single  flow  and  return, 
the  pipe  is  carried  back  to  the  furnace  and  a  second  coil  made,  and  then  the 
pipe  proceeds  again  to  another  part  of  the  building  and  returns  to  be  con- 
nected with  the  end  of  the  first  circulation.  This  may  be  repeated  several 
times,  so  that  the  pipe  may  start  from  the  furnace  and  return  to  it  again, 
start  again,  and  come  back,  four  or  five  times  before  the  circuit  is  complete. 
In  general,  a  circulation  with  one  coil  only  in  the  furnace  consists  of  1500 
feet,  150  feet  being  exposed  to  the  fire  ;  if  a  second  1500  feet  are  required  the 
circuit  includes  another  150  feet  in  the  fire,  and  so  on.  Thus  the  same  water 
passes  through  the  whole  length  of  pipe,  however  great  it  may  be,  but, 
generally,  not  more  than  7500  feet  are  heated  by  a  single  furnace. 


136  HYGIENE 

The  water  in  the  pipes  wastes  to  a  certain  extent,  although  the  whole  is 
closed  lip,  so  that  the  plugs  at  the  top  are  periodically  taken  out  and  a  httle 
water  added. 

The  high  temperatiire  of  the  pipes,  though  useful  and  desirable  from  the 
fact  that  the  distribution  of  heat  takes  place  to  a  greater  extent  by  radiation 
than  is  the  case  with  low-pressure  systems,  requires  that  the  system  should 
be  introduced  with  proper  precautions.  The  insurance  companies  require 
the  pipes  to  be  at  least  one  inch  from  the  woodwork,  and  this  is  no  doubt 
generally  desirable  and  should  be  provided  for.  Should  a  pipe  for  any  reason 
become  stopped,  the  pressure  reaches  an  uncontrollable  magnitude,  but  the 
weakest  part  is  that  in  the  fire,  so  that  it  bursts  there,  and  the  fissure  is  said 
to  be  so  small  that  the  water  issues  as  a  jet  of  steam  without  douig  any 
serious  damage. 

Distribution  of  Heat  by  Steam  Pipes 

77.  There  are  many  plans  for  keeping  a  series  of  pipes  hot  by  the  circula- 
tion of  steam,  and  they  differ  in  the  form  of  the  pipes  and  the  pressure  of  the 
steam  employed.  If  the  system  is  well  arranged  the  heat  is  developed  by 
the  condensation  of  the  steam,  and  no  steam  leaves  the  pipes  but  only  the 
condensed  water,  which  may  be  returned  to  the  boiler  by  suitable  apparatus. 
The  condensation  of  the  steam  causes  a  rattling  noise  in  the  pipes  which  is 
sometimes  disagreeable.  The  pressure  of  steam  in  the  pipes  is  in  any  case 
limited  by  the  safety-valves  of  the  boiler,  but  when  low-pressure  steam  is 
reqmred  from  a  high-pressure  boiler  a  reducing  valve  may  be  introduced. 
For  further  information  the  reader  may  be  referred  to  a  paper  '  On  the 
American  Practice  of  Warming  Buildings  by  Steam,'  by  the  late  Eobert 
Briggs  ( '  Proc.  Inst.  C.E.'  vol.  Ixxi.  1882-3,  p.  95,  with  the  discussion 
thereupon). 

Amount  of  Heating  Sueface  Eequered  for  Waeming  Buildings 

78.  The  calculation  of  the  amount  of  hot-water  piping  of  given  external 
diameter  that  may  be  necessary  for  the  adequate  warming  of  a  building 
depends  upon  a  large  number  of  elements.  Provision  must  be  made  for  the 
loss  of  heat  by  conduction  through  the  walls  and  windows,  as  well  as  for 
that  carried  away  by  the  air  in  the  process  of  ventilation.  Both  these  are 
variable  quantities  depending  upon  the  state  of  the  weather ;  moreover,  in 
calculating  the  former,  the  nature  and  thickness  of  the  walls  and  the  area  of 
window  surface  must  be  known,  and  for  the  latter  more  heat  will  be  required, 
if  for  any  reason  the  ventilation  flow  is  more  active,  and  less  if  the  ventilation 
is  restricted.  AVe  have  not  space  to  indicate  the  details  of  the  calculation  in 
special  cases.  An  additional  disturbance  of  the  calculation  is  introduced  if  a 
room  is  occupied  by  a  large  number  of  persons  or  if  artificial  light  is  employed. 
It  must  be  assumed  that  the  amount  of  heat  available  shall  be  sufficient  to 
raise  the  temperatm^e  to  the  highest  point  required  in  the  coldest  weather 
likely  to  be  experienced,  and  with  the  fullest  ventilation  which  the  cir- 
cumstances require.  The  supply  can  then  be  restricted  by  a  valve  on  the 
apparatus  if  the  conditions  are  such  that  a  reduction  of  temperature  is 
desirable. 

In  order  to  enable  the  reader  to  determine  approximately  the  length  of 
low-pressure  water  pipe  required,  we  give  a  table  from  Hood's  '  Warming  of 
Buildings,'  p.  119,  showing  the  length  of  4-inch  pipe  at  200°  F.  necessary 
to  warm  given  quantities  of  air.  If  the  diameter  of  pipe  is  increased  in  any 
ratio  the  length  required  will  be  reduced  in  the  same  ratio.     Thus  200  feet 

of  4-inch  pipe  can  be  replaced  by  -  x  200  feet  of  3-inch  pipe  and  so  on. 

o 


WABMING  AND   VENTILATION 


137 


'  The  quantity  of  air  to  be  warmed  per  minute  in  habitable  rooms  and  n 
pubHc  buildings  must  be  from  three  and  a  half  to  five  cubic  feet  for  each 
person  the  room  contains,  and  one  and  a  quarter  cubic  foot  for  each  square 
foot  of  glass.' 

If  the  high-pressure  system  is  employed,  the  necessary  area  of  surface  is 
very  much  reduced  inconsequence  of  the  higher  temperature  which  is  reached. 

Table  XIII 

■SJioioing  the  Length  in  Feet  of  Pipe,  4  Inches  in  Diameter,  which  will  heat  1000  Cubic 
Feet  of  Air  per  Minute  any  required  number  of  Degrees,  the  Temperature  of  the 
Pipe  being  200°  Fahr.     (Hood.) 


Temperature  of 

Temperature  at  which  the  room  is  re 

quired  to  be  kept 

external  air, 

Fahrenheit's 

scale 

45° 

50° 

55° 

60° 

65° 

70° 

75° 

80° 

85° 

90° 

10° 

126 

150 

174 

200 

229 

259 

292 

328 

367 

409 

12° 

119 

142 

166 

192 

220 

251 

283 

318 

357 

399 

14° 

112 

135 

159 

184 

212 

242 

274 

309 

347 

388 

16° 

105 

127 

151 

176 

204 

233 

265 

300 

337 

378 

18° 

98 

120 

143 

168 

195 

225 

256 

290 

328 

368 

20° 

91 

112 

135 

160 

187 

216 

247 

281 

318 

358 

22° 

83 

105 

128 

152 

179 

207 

238 

271 

308 

347 

24° 

76 

97 

120 

144 

170 

199 

229 

262 

298 

337 

26° 

69 

90 

112 

136 

162 

190 

220 

253 

288 

327 

28° 

61 

82 

104 

128 

154 

181 

211 

243 

279 

317 

30° 

54 

75 

97 

120 

145 

173 

202 

234 

269 

307 

Freezing)  ggo 
point  i  3^o 

47 

67 

89 

112 

137 

164 

193 

225 

259 

296 

40 

60 

81 

104 

129 

155 

184 

215 

249 

286 

36° 

32 

52 

73 

96 

120 

147 

175 

206 

239 

276 

38° 

25 

45 

66 

88 

112 

138 

166 

196 

230 

266 

40° 

18 

37 

58 

80 

104 

129 

157 

187 

220 

255 

42° 

10 

30 

50 

72 

95 

121 

148 

178 

210 

245 

44° 

3 

22 

42 

64 

87 

112 

139 

168 

200 

235 

46° 

15 

34 

56 

79 

103 

130 

159 

190 

225 

48° 



7 

27 

48 

70 

95 

121 

150 

181 

214 

50° 





19 

40 

62 

86 

112 

140 

171 

204 

52° 

— 

— 

11 

32 

54 

77 

103 

131 

161 

194 

To  ascertain  by  the  above  table  the  length  of  pipe  which  will  heat  1000  cubic  feet  of 
air  per  minute,  find,  in  the  first  column,  the  temperature  corresponding  to  that  of  the 
external  air,  and  at  the  top  of  one  of  the  other  columns  find  the  temperature  at  which 
the  room  is  to  be  maintained ;  then,  in  this  latter  column,  and  on  the  line  which 
corresponds  with  the  external  temperature,  the  required  number  of  feet  of  pipe  will  be 
found. 

We  quote  also  from  the  same  work  (§  111)  some  empirical  rules,  giving 
the  length  of  4-inch  pipe  required  for  rooms  of  different  sizes  and  character. 
We  have  omitted  the  footnotes  which  apply  to  certain  special  cases. 

'  Churches  and  large  Public  Booms 
*■  To  heat  these  when  they  have  an  average  number  of  doors  and  windows, 
and  only  moderate  ventilation,  divide  the  cubic  measurement  of  the  building 
by  200,  and  the  quotient  will  be  the  number  of  feet  in  length  of  pipe  four 
inches  diameter  that  will  be  required  to  produce  a  temperature  of  about  55° 
in  very  cold  weather.  This  is  equivalent  to  allowing  five  feet  of  i-inch 
pipe  for  every  thousand  cubic  feet  of  space  which  the  building  contains.  If 
the  apparatus  is  so  contrived  that  the  warming  of  the  air  is  effected  before  it 
actually  circulates  in  the  room,  and  that  the  same  portions  of  air  are  not 
returned  to  be  heated  a  second  time,  but  fresh  portions  of  external  air  are 
brought  successively  in  contact  with  the  heating  apparatus,  it  will  reqmre 
from  50  to  70  per  cent,  more  pipe  to  produce  the  same  effect ;  but  the  air 
will,  of  course,  be  more  pure  and  fresh. 


138  HYGIENE 

'  Dwelling-rooms 

*  These  will  generally  require  about  twelve  feet  of  4-incli  pipe  to  every 
thousand  cubic  feet  of  space  contained  in  them  to  give  a  temperature  of 
about  G5°"  To  raise  the  temperature  to  70°  will  require  about  fourteen  feet 
of  4-inch  pipe. 

'Halls,  shojis,  tuaiting-roovis,  &c.  will  require  about  ten  feet  of  4-incli 
pipe  to  every  thousand  cubic  feet  of  space  to  raise  the  temperature  to  about 
55°.  For  a  temperature  of  60°  about  twelve  feet  of  4-inch  pipe  will  be 
required. 

'  ScJiools  and  lecture-rooms,  i^equiring  a  temperature  of  55°  to  58°,  will 
require  from  six  to  seven  feet  of  4-inch  pipe  to  every  thousand  cubic  feet  of 
space. 

'  Drying-rooms,  or  closets  for  drying  wet  linen  and  other  substances,, 
require  from  150  to  200  feet  of  4-inch  pipe  to  every  thousand  cubic  feet 
of  space  to  raise  the  temperature  to  1'20°  when  empty,  or  about  80°  when 
the  room  is  filled  with  wet  linen. 

*  Drying-rooms  for  curing  bacon,  or  for  drying  paper,  or  leather,  or  damp 
hides,  will  require  twenty  feet  of  4-inch  pipe  to  every  thousand  cubic  feet 
of  space  to  give  a  temperature  of  about  70°. 

'  Greenliouses  and  conservatories  requiring  a  temperature  of  about  55° 
in  the  coldest  weather  must  have  thirty-five  feet  of  4-inch  pipe  for  each: 
thousand  cubic  feet  of  space  they  contain.' 

Waeming  Apparatus  in  Eelation  to  Ventilation 

79.  Heat  may  be  used  in  two  ways  in  a  ventilation  system  :  first,  to- 
produce  a  head  in  an  outlet  flue  for  the  extraction  of  air,  and  secondly  to 
warm  the  air  of  the  rooms  or  that  supplied  to  the  inlets.  We  have  sufficiently 
dealt  with  the  first  application  of  heat.  As  to  the  second,  we  merely  wish 
now  to  reiaiark  upon  the  effect  of  the  warming  apparatus  upon  the  state  of 
the  air.  We  have  akeady  (§  5G)  pointed  out  a  danger  in  the  case  of  iron. 
stoves,  and  the  remarks  in  Table  XI.  §  6G  indicate  the  healthiness  or  other- 
wise of  the  systems  of  warming  there  referred  to. 

The  air  which  is  warmed  by  passing  over  heating  surfaces  of  any  kind  is 
dried  in  consequence,  and  this  effect,  being  dependent  only  upon  the  extent 
to  which  the  temperature  is  raised,  is  the  same  whatever  system  of  warming 
be  adopted,  and  can  only  be  counteracted  by  furnishing  the  air  with  an 
additional  supply  of  moisture.  The  hot- water  systems  and  steam-heating 
systems  should  not  of  themselves  deteriorate  the  air  which  they  warm,  but 
the  pipes  which  carry  the  Avater  or  steam  are  generally  put  in  out-of-the- 
way  places,  which  are  very  liable  to  become  receptacles  for  dirt  of  one  sort 
or  another.  A  considerable  accumulation  is  likely  to  take  place  during  the 
summer  months  when  the  apparatus  is  not  in  use,  and  when  the  pipes  are 
heated  for  the  winter  the  dust  becomes  subjected  to  a  process  of  distillation,, 
and  the  air  is  consequently  fouled.  The  pipes  should  therefore  be  laid  in 
such  a  manner  that  they  can  be  periodically  and  properly  cleaned.  The 
injurious  action  upon  the  air  depends,  other  things  being  equal,  upon  the 
temperature,  so  that  the  high-pressure  system  is  likely  to  cause  greater 
annoyance  in  this  respect  than  the  low-pressure  pipes  ;  but  if  the  pipes  are 
properly  cleaned  there  seems  no  reason  to  anticipate  the  fouling  of  the  air  by 
either  system. 

What  is  here  said  about  hot-water  pipes  apphes  to  a  modified  extent  to 
all  channels  for  the  supply  of  fresh  air.     They  are  always  liable  to  be  fouled,. 


WABMING  AND   VENTILATION  139' 

and  require  cleaning,  and  if  the  openings  are  covered  with  gauze  or  gratings 
the  deposit  of  dirt  tliere  may  seriously  interfere  with  the  supply  of  air,  both 
as  regards  its  quantity  and  its  quality. 


Aetificial  Coolino 

80.  A  corollary  to  the  general  problem  of  maintaining  the  air  of  an  in- 
habited room  at  the  temperature  most  suitable  for  its  occupants  is  the  con- 
sideration of  the  means  of  reducing  the  temperature  in  summer  if  the  weatlier 
should  render  such  a  reduction  desirable.  In  an  early  section  (§  6)  we  con- 
sidered the  means  of  preventing  the  communication  of  heat  between  a  room 
and  the  external  air,  but  the  only  special  precautions  in  general  use  to  prevent 
a  too  high  temperature  in  summer  are  to  shut  the  windows  and  cover  them 
with  outside  blinds,  or  louvre  shutters,  to  prevent  the  direct  radiation  of  the- 
sun  from  penetrating  to  the  room,  and  to  whitewash  the  roofs,  in  order  that 
the  heat  of  the  sun's  rays  may  be  dissipated  by  the  diffuse  radiation  from 
the  white  surface.  The  effect  of  the  first  precaution  is  most  easily  apparent ; 
what  the  effect  of  the  second  may  be  it  is  difficult  to  estimate,  except  in  a 
most  general  way. 

Another  method  of  keeping  a  room  cool  in  summer  is  to  supply  it  with 
air  which  passes  through  an  underground  channel ;  but  such  a  method  is  not 
often  adopted,  and  the  air  is  likely  to  be  fouled,  even  to  the  extent  of  having 
a  mouldy  smell,  unless  special  precautions  are  taken  to  keep  the  channel  dry 
and  clean. 

If  the  outside  air  is  dry,  it  can  be  cooled  considerably  on  its  passage  inta 
a  room  by  being  made  to  pass  over  wet  surfaces  of  linen  &c.  or  by  the  injec- 
tion of  water  spray.  The  cooling  in  this  case  arises  from  the  evaporation  of 
water  into  the  comparatively  dry  air,  and  the  water  so  evaporated  is  carried 
by  the  passing  air  into  the  room  to  be  cooled.  The  air  is  thus  nearly 
saturated  by  the  cooling  process,  and  the  moistening  may  easily  be  carried 
further  than  is  generally  desirable.  But  on  this  point  it  must  be  remembered 
that  any  cooling  of  air  necessarily  causes  it  to  approach  the  saturation  point 
(see  p.  45)  unless  moisture  is  abstracted  when  the  cooling  is  effected. 

81.  Of  late  years  there  has  been  a  great  development  of  machines  for  the 
artificial  production  of  ice  or  the  supply  of  cold  air.  Such  machines  may 
be  arranged  in  three  classes  :— 

(1)  Machines  in  ivliicli  the  cooling  is  produced  by  the  evaporation  of  a  volatile 
liquid  in  one  vessel,  the  vapour  formed  being  absorbed  by  water  or  some 
other  liquid  in  another  vessel  connected  with  the  first 

Carre's  ammonia  machine  is  one  of  the  best  known  examples  of  tliis 
method.  A  solution  of  ammonia  gas  in  water  is  first  placed  in  a  vessel,  which 
we  may  call  a  boiler,  and  the  boiler  is  connected  with  a  second  vessel,  a  con- 
denser. The  boiler  is  first  heated  to  about  250°  F.  and  the  condenser 
meanwhile  cooled  by  immersion  in  a  water  tank ;  the  ammonia  is  driven 
off  from  its  solution  and  the  pressure  reaches  so  high  a  point  that  the 
ammonia  gas  condenses  to  a  liquid  in  the  condenser,  giving  out  a  large 
quantity  of  heat  in  so  doing  to  the  water  of  the  tank.  The  apparatus  is  then 
removed  from  the  furnace  and  the  tank  ;  the  boiler  is  next  immersed  in 
water,  and  the  condenser  is  surrounded  by  the  water  to  be  frozen.  The 
cooled  water  in  the  boiler  reabsorbs  the  ammonia  vapour  and  reduces  the 
pressure,  and  thus  determines  the  evaporation  of  the  ammonia  liquid  and  a 
consequent  large  reduction  of  temperature  in  that  liquid  and  the  vessel  which 


140  HYGIENE 

surrounds  it.  By  repeating  the  process  successive  quantities  of  heat  are 
removed  from  the  vessel  surrounding  the  condensed  ammonia.  With  a 
large  apparatus  of  this  kind,  arranged  for  continuous  instead  of  intermittent 
cooling,  ice  is  said  to  be  producible  at  the  very  low  rate  of  twopence  per 
hundredweight.     (Peclet,  *  Traite  de  la  Chaleur,'  tome  iii.  p.  149.) 

Another  of  Carre's  apparatus  in  which  heat  is  absorbed  by  the  rapid 
evaporation  of  water  at  low  pressure,  the  vapour  being  absorbed  by  sulphuric 
acid,  is  also  an  example  of  this  type  of  machine. 

(2)  Machines  in  tvhich  cold  is  produced  by  the  expenditure  of  mechanical 
work  in  the  evaporation  of  a  liquid 

We  have  already  seen  that  water  evaporates  at  all  temperatures ;  the 
amount  of  evaporation  depends  upon  the  pressure  to  which  the  surface  is 
exposed.  The  same  is  true  of  other  liquids,  and  advantage  is  taken  of  this 
in  the  production  of  cold  or  abstraction  of  heat.  The  rate  of  evaporation  is 
very  slow  if  there  is  any  considerable  pressure  of  air  on  the  surface  of  the 
liquid,  so  that  the  first  step  in  the  manipulation  of  an  apparatus  of  this 
kind  is  to  pump  out  the  air.  If  we  suppose  the  air  removed,  we  may  con- 
sider two  vessels  which  are,  so  to  speak,  in  communication  through  an  air- 
pump,  that  is  to  say,  as  the  pump  is  worked  any  air  or  vapour  in  the  one 
vessel  will  be  gradually  pumped  out  and  dehvered  to  the  other.  The  result 
is  that  if  a  volatile  liquid  be  contained  in  each  of  the  vessels  the  vapour  will 
be  pumped  from  the  one  vessel  to  the  other,  and,  in  consequence,  continuous 
evaporation  will  take  place  in  the  one  vessel  and  continuous  condensation 
in  the  other.  This  imphes  a  continuous  absorption  of  heat  for  the  forma- 
tion of  vapour  in  the  one  vessel  and  a  continuous  development  of  heat 
by  condensation  in  the  other.  Thus  by  keeping  the  pump  working  heat 
passes  from  the  cold  evaporating  liquid  and  its  surroundings  to  the 
hotter  condensing  liquid  and  its  surromidings.  By  adding  some  arrange- 
ment for  the  transference  of  the  hquid  back  to  the  evaporating  vessel  the 
process  may  go  on  continuously.  Such  an  apparatus  can  therefore  be  used 
either  as  a  cooling  apparatus  or  as  a  warming  apparatus,  whichever  may  be 
desired. 

If  heating  is  wanted,  the  cold  vessel  should  be  surrounded  with  an  ample 
supply  of  water  to  keep  up  its  temperature  ;  if  cooling  is  desired,  the  heat 
developed  by  the  condensation  may  be  thrown  away  by  allowing  it  to  pass 
into  the  outside  air  or  a  tank  of  water.  This  is  one  instance  already  alluded 
to  of  the  employment  of  mechanical  work  (viz.  that  required  to  work  the 
pump)  for  the  purpose  of  heating  or  cooling.  But  an  important  and  inter- 
esting point  in  connexion  with  it  is  that  the  heating  effect  is  greater  than 
the  mechanical  equivalent  of  the  power  employed  to  drive  the  pump.  In 
fact,  neglecting  losses,  the  heat  which  is  given  to  the  condensing  vessel  is 
greater  than  the  amount  equivalent  to  the  work  done  in  pumping,  by  the 
amount  drawn  from  the  evaporating  vessel.  An  ideal  arrangement,  as  sug- 
gested by  Sir  Wilham  Thomson,  would  be  to  make  use  of  both  the  heating 
and  cooling  effects  of  such  an  arrangement ;  suppose,  for  mstance,  that  an 
arrangement  of  tliis  kind  were  used  for  warming  a  house  in  winter,  then  it 
might  at  the  same  time  be  producing  ice,  which  could  be  stored  in  a  suitable 
ice-house  for  use  in  summer,  and  we  should  thus  be  able,  in  a  sense,  to 
equalise  the  distribution  of  summer  and  winter  temperature  inside  the  house 
by  locaHsing  the  loss  of  heat  in  winter,  and  storing  it,  so  to  speak,  in  the 
ice. 

But  we  are  not  aware  that  this  ideal  arrangement  for  using  both  ends  of 
a  mechanical  heating  and  cooling  apparatus  has  ever  been  put  into  practice. 


WABMING  AND   VENTILATION  141 

The  one  end  of  it,  the  cold  producer  with  methylic  ether  as  the  evaporating 
Hquid,  has,  however,  found  appKcation  on  a  commercial  scale.  It  is  one  of 
the  methods  used  in  the  cooling  of  ships  employed  for  the  carriage  of  meat. 
By  the  cooling  apparatus  the  meat  is  kept  in  a  current  of  dry  air  very  near 
the  freezing-point,  and  is  thus  kept  fresh  during  long  voyages.  An  apparatus 
by  MM.  E.  Pictet  et  Cie.,  with  sulphurous  acid  as  the  evaporating  liquid, 
was  used  to  cool  glycerine  to  such  an  extent  as  to  freeze  the  surface  of 
water  of  an  artificial  ice  skating  rink.  The  price  assigned  to  the  production 
of  ice  on  a  large  scale  by  this  apparatus  is  fourpence  per  hundredweight. 

(3)  Machines  in  which  cold  is  produced  by  the  expansion  of  air 

The  dynamical  coohng  of  air  has  already  been  referred  to  and  accounted 
for.  The  considerable  fall  of  temperature  corresponding  to  the  expansion 
of  air  from  considerable  pressures  to  the  atmospheric  pressure  shown  in  the 
table  of  page  43  shows  that  if  this  expansion  could  be  arranged  on  a  large 
scale  cooling  could  be  effectively  carried  on.  The  air  must  not,  however,  be 
allowed  simply  to  blow  out  through  a  fine  nozzle,  for  in  that  case  the  fall  of 
temperature  would  be  greatly  reduced  in  consequence  of  friction  at  the  nozzle. 
It  is,  in  fact,  desirable  to  pass  the  compressed  air  through  an  engine,  and  let 
it  do  some  such  work  as  pumping  water,  or  driving  a  knife  machine,  a 
shoe-blacking  machine,  or  an  electric-lighting  dynamo,^  in  order  that  the 
greatest  effect  may  be  produced.  As  we  have  to  start  with  uncompressed 
air  it  would  be  necessary  for  the  installation  of  a  cooling  apparatus  on  this 
plan  to  provide  for  the  compression  of  the  air  by  a  second  engine  ;  the  com- 
pression would  heat  the  air,  and  the  heat  so  generated  is  a  waste  product  of 
the  cooling  apparatus,  but  might  be  employed  in  heating  buildings  while  ice 
was  being  produced  by  the  expansion ;  and  we  should  thus  get  an  arrange- 
ment similar  to  that  indicated  for  the  evaporation  machines  in  which  the 
whole  plant  would  consist  of  a  compressing  engine,  delivering  hot  compressed 
air  which  may  be  cooled  and  then  passed  into  an  expansion  engine,  which 
delivers  the  air  cooled  to  an  extent  depending  on  the  difference  of  its  pressure 
in  the  compressed  and  uncompressed  states.  But  the  supply  of  compressed 
air  at  ordinary  temperatures  to  houses  and  workshops  is  now  becoming  a 
commercial  matter  in  some  large  towns,  just  as  the  supply  of  gas  or 
electricity  has  become ;  and  in  that  case  the  householder  requires  only  an 
engine  providing  for  the  expansion  of  the  air  and  performing  the  useful  work 
indicated  above,  in  order  to  get  ice-cold  air,  and  so  produce  ice  itself  if  it  is 
wished.  A  most  interesting  account  of  the  way  in  which  such  a  system  of 
distribution  of  compressed  air  is  employed  in  Paris  (Popp's  system)  is  given 
by  Professor  A.  B.  W.  Kennedy  in  the  *  British  Association  Report  for  1889/ 
p.  448,  and  '  Engmeering,'  Sept.  13,  1889. 


COMBINATIONS   OF  APPAEATUS   FOE  HOUSES   AND 
LARGE   BUILDINGS 

81.  It  now  remains  for  us  to  consider  the  combinations  of  apparatus  that 
have  been  employed  to  provide  for  the  efficient  warming  and  ventilation  of 
large  rooms  and  buildings.  The  plans  which  have  been  adopted  in  different 
cases  are  extremely  numerous  and  varied,  and  the  accounts  of  the  per- 
formances of  the  different  apparatus  are  not  easily  compared.     Sometimes 

'  In  a  paper  in  La  Lumi&re  Electrigue,  tome  xi.  1884,  p.  421,  Prof.  Lippmann  calls 
special  attention  to  the  thermal  economy  of  such  an  arrangement. 


142  HYGIENE 

the  ventilation  depends  entirely  upon  the  draft  of  a  large  chimney-stack, 
the  different  rooms  or  parts  of  a  large  hall  heing  connected  with  the  stack  by 
separate  ducts  ;  in  others  the  large  chimney  is  replaced  by  a  fan  ;  and  either 
of  these  plans  may  be  supplemented  by  open  fires  or  separate  ventilating 
Hues,  or  the  propulsion  or  plenum  method  may  be  employed  as  a  substitute 
or  an  addition  to  the  other  forms  of  apparatus.  The  published  descriptions 
or  statistical  information  as  to  the  action  of  the  systems  in  actual  use  are 
seldom  so  arranged  as  to  enable  the  reader  to  form  a  very  precise  opinion 
of  the  merits  of  the  particular  j)lan  adopted.  In  warming  and  ventilation, 
perhaps  more  tlian  any  other  subject,  success  or  failure  depends  upon 
small  details  that  may  be  passed  over  in  description,  and  slight  changes  that 
seem  at  first  sight  unimportant  may  entirely  change  the  aspect  of  the 
question,  particularly  when  economy  is  an  important  element  for  considera- 
tion ;  for  instance,  a  system  which  can  be  applied  successfully  to  a  high 
building  of  several  stories  may  prove  to  be  a  failure  when  introduced  into  a 
building  of  the  same  cubic  content  distributed  over  a  wide  area  in  a  single 
story. 

How  unsatisfactory  the  comparison  may  be  in  the  question  of  coat  may 
be  gathered  from  the  following  extract  from  the  very  valuable  report  of 
Professor  Carnelley  upon  the  cost  and  efficiency  of  the  heating  and  ventila- 
tion of  schools.^  He  says  (p.  45) :  '  In  Nottingham  (open  fires)  they  burn 
nearly  five  times  as  much  coal  per  head  as  in  Dundee,  and  although  coal  is 
not  much  more  than  one-half  the  price,  yet  it  costs  them  nearly  three  times 
as  much  per  head  of  accommodation.  The  most  extravagant  "  open  fire" 
school  in  Dundee  only  burns  one-half  as  much  coal  per  head  as  the  most 
careful  "  open  fire  "  school  in  Nottingham.  One  open  fire  school  in  Dundee 
burns  only  23  lb.  per  head,  while  one  of  the  open  fire  schools  in  Leeds  burns 
as  much  as  2391b.  per  head!  One  of  the  "large  hot  pipe"  schools  in 
Dundee  bm-ns  only  341b.  of  coal  per  head,  while  one  of  the  "large  hot 
pipe  "  schools  in  Nottingham  burns  417  lb.  per  head.  Either,  then,  they  are 
inordinately  extravagant  in  such  towns  as  Leeds,  Sheffield,  Nottingham,  &c. 
and  are  roasting  the  children,  or  we  in  Dundee  are  freezing  them  for  the 
benefit  of  the  ratepayers.  It  is  to  be  noted  that  the  same  thing  occurs,  no 
matter  what  system  of  natural  heating  and  ventilation  is  adopted.  The 
result,  therefore,  cannot  be  due  to  any  superior  efficiency  of  our  heating 
arrangements  in  Dundee.' 

82.  The  report  from  which  the  above  extract  is  quoted  is  a  very  complete 
arrangement  of  the  results  of  an  investigation  of  the  ventilation  and  warming 
of  323  schools,  of  which  150  were  personally  visited.  We  give  a  few  of  the 
important  conclusions  from  the  summary  on  pp.  43-48. 

First  Cost  of  System  of  Warming  and  Ventilation 

Per  heurl  of  Per  school  of 

accommodation  lOOU  pupils 

s.  £ 

(  Open  fires 4  200 

Natural  ventilation  <  Small  hot-water  pipes  (higti  pressure)       8  400 

I  Large  hot-water  pipes  (low  pressure)  .     10  600 
,_    ,      .    ,           ,.    rAs   applied   to   schools    suitably   de- 

iation''                '  \      '^Sned 17  850 

LAs  applied  to  ordinary  schools    .         .     20  1000 

'  Presented  to  the  School  Board  of  Dundee.  Published  by  Winter,  Duncan,  &  Co., 
Dundee. 


WABMING  AND   VENTILATION 


143 


Total  Annual  Cost 


- 

Cost  per  head  of 
accommodatioii 

Cost  for 

a  school  to  accommodate  1000 
children 

Interest  on 
tlrst  cost 

Annual 
cost 

Total 
annual  cost 

Interest  on 
first  cost 

Annual  cost 

Total 
annual  cost 

Ordinary  systems 
Mechanical  system    . 

Difference     . 

d. 

H 

8 

d. 

'2 

d. 

6 

15| 

£ 
14 
34 

£     s.    d. 
11     9     2 
31     5     0 

£    s.    d. 
25     9     2 
65     5     0 

5 

A3. 

*4 

9^ 

20 

19  15  10 

39     5  10 

Efficiency  &c. 
(a)  Badiation  v.  Conduction.-mth  those  systems,  in  which  the  rooms  are  heated  by 
TadaionratheJthan  by  conduction,  the  air  is  much  more  highly  charged  with  micro- 
orglntms "han  with  those  systems  in  which  the  rooms  are  heated  more  by  conduction 

"^^M^^r   Grates  v.   Ordinary   Grates.-Ks  regards  open  fires,  'Manchester 
.rate   '  ^  are  much  more  effective  in  keeping  the  air  of  the  rooms  pure  than  ordinary  grates. 
^      c    Meclanical..  Ordinary  S.si.^s.-Mechanical  ventilation  .s  undoubted^^^^^^^^ 
effect  ve  in  maintaining  the  purity  and  temperature  of  the  air  m  schools  than  any  of  the 
ofdtaly  methods  usually  adopted,  and  is  hence  more  conducive  to  health  and  comfort 

i^Gas  Engines  and  Water  Engines.-G^s  engines  are  much  cheaper  and  more  effective 

-than  water  engines  for  driving  the  fans.  ^e  •     4. 

Te)  PolTo/  Gas  Engine  reguired.-K  two  horse-power  gas  engme  is  arnply  sufficient 

ior  drivinga  4  ft.  Blackman  or  Aland  fan  (even  one  horse-power  would  probably  be 

sufficient)f  while  a  one  horse-power  [engine]  is  sufficient  for  six  of  Cunmngham  s  fans. 

(  f )  Bloiving  in  v.  Expanding  the  ^ir.-The  former  is  preferable. 

L)i;S!s/a/is.-One  large  fresh-air  inlet  shaft  is  much  better  than  several  small 
■ones,  and  the  entrance  to  the  shaft  should  be  as  free  as  possible. 

(h)  Air  FiZiers.— Recommended.     (See  p.  51.)  .   .^  -di    i  ^„„ 

(i)  Blackman's  v.  Cimninqham^s  Fans.-\Nhen  properly  arranged,  a  4  "•  Blackman 
fan  appears  to  be  more  effective  and  costs  less  both  in  fuel  and  in  annual  cost  than  the 
te  or  sS  Cunningham's  fans  usually  employed  to  do  the  same  work.  Cunmngharn  s 
tnsarriioweverrmore  independent  of  the  weather  than  either  Blackman's   or  Aland's 

^'""(i)  Time  reguvred  to  Change  the  Air  of  a  School  by  Mechanical  F.niiZaiion -By 
mechanical  ventilation  the  whole  of  the  air  in  a  school  may  be  easily  changed  m  less  than 
Steen  minutes,  and  when  the  system  is  well  arranged  m  less  than  ten  mmutes. 

The  Statistics  upon  which  these  conclusions  are  based  are  given  in  the 
iextand  tables  of  the  report.  Some  of  the  data  must  be  modified  when 
■specially  large  or  small  schools  are  referred  to.  We  qiTote  also  from  the 
same  report  (p.  41)  the  following  tabular  statement  of  the  advantages  and 
■disadvantages  of  the  several  systems  :— 

Open  Fires 

Advantages : 

1.  More  cheerful. 

2   First  cost  much  less  than  hot  pipe  systems. 

3'  Keeps  air  fresher  than  hot  pipes,  owing  to  draught  up  chimney. 

4    So  far  as  the  Dundee  schools  are  concerned,  the  temperature  m  the  open  fiie 

schools  was  higher  than  in  those  heated  by  hot  pipes. 
5.  The  rooms  of  these  schools  will  probably  need  painting  less  frequently  than  those 

heated  by  other  systems. 
Disadvantages : 

2.  SS;^:.^— cost  than  stoves,  or  steam-pipes,  or  large  hot-water  pipes. 

>  A  form  of  ventilating  open  grate  (see  p.  124)  delivering  fresh  air  above  the  mantel- 
shelf. 


144  HYGIENE 

3.  Unequal  distribution  of  heat. 

4.  Air  more  highly  charged  with  micro-organisma. 

Stoves 
Advantages : 

1.  Smallest  first  cost. 

2.  Least  annual  cost. 

3.  Probably  more  effective  heaters  than  open  fires. 
Disadvantages : 

1.  Greater  labour  in  service. 

2.  Require  more  attention  than  open  fires. 

3.  More  liable  to  smoke  than  open  fires. 

4.  More  liable  to  get  out  of  repair  than  open  fires. 

5.  Not  so  cheerful  as  open  fires. 

Hot  Pipes 
Advantages : 

1.  Less  labour  in  service  than  either  open  fires  or  stoves. 

2.  The  class  is  not  disturbed  as  in  the  case  of  the  mending  open  fires  and  stoves. 

3.  More  equal  distribution  of  heat. 

4.  Air  less  charged  with  micro-organisms  than  when  open  fires  are  used. 

5.  On  the  whole  the  annual  cost  is  probably  slightly  less  than  with  open  fires,  but 

more  than  with  stoves. 
Disadvantages : 

1.  Not  so  cheerful  as  open  fires. 

2.  First  cost  much  more  than  in  the  case  of  open  fires  or  stoves. 

3.  Air  not  so  fresh  as  with  open  fires. 
On  hot-pipe  scJwols. 

1.  Small  high-pressure  pipes  are  cheaper  in  first  cost  than  large  low-pressure  pipes. 

2.  Li  those  schools  examined  the  air   was  better  in  rooms  heated  by  small  high- 

pressure  pipes  than  in  those  heated  by  large  low-pressure  pipes. 

3.  It  takes  longer  to  get  up  the  heat  with  large  than  with  small  pipes. 

4.  Small  pipes  are  less  obtrusive  in  the  rooms. 

MechanicaIi  Ventilation 
Advantages : 

1.  Much  greater  purity  as  regards  all  the  constituents. 

2.  Efficiency  of  ventilation  much  more  independent  of  the  weather ;  whereas  with 

other  systems  the  ventilation  is  worst  when  most  needed. 

3.  The  schools  are  warmer. 

4.  More  equal  distribution  of  heat  and  of  fresh  air. 

5.  Very  effective  in  diminishing  the  number  of  micro-organisms,  not  only  at  the 

time  the  mechanical  ventilation  is  in  operation,  but  also  for  a  long  time  after 
it  has  been  stopped. 

6.  Eeduces  draughts  to  a  minimum. 

In  fact,  the  mechanical  system  heats  and  ventilates  far  better  in  every 
respect  than  any  other  system,  and  is  therefore  far  more  conducive  to  health, 
and  comfort,  and  to  success  in  teaching  and  learning. 
Disadvantages  : 

1.  Greater  first  cost. 

2.  Greater  annual  cost  (except  in  the  case  of  very  large  schools). 

3.  Though  in  a  town  where  several  schools  were  heated  and  ventilated  mechanically 

there  would  not  need  to  be  more  than  an  ordinary  caretaker  in  each  of  such 
schools,  yet  one  of  these  should  be  a  man  who  had  some  knowledge  of  gas 
engines  &c.  so  that  he  could  attend  to  any  repairs  which  might  be  necessary. 
Such  a  man  would  require  a  somewhat  higher  wage  than  an  ordinary  caretaker. 
This,  however,  would  amount  to  very  little  if  distributed  over  a  number  of 
schools. 

We  are  unable  to  present  such  statistical  information  in  a  condensed  form 
for  other  kinds  of  builduigs,  and  we  do  not  think  that  much  valuable  infor- 
mation can  be  derived  from  a  general  account  of  the  ventilation  and  warming 
of  any  particular  building  without  the  details  upon  which  its  success  or 
failure  depends.   We  therefore  think  it  best  to  give  here  references  to  published 


WABMING  AND    VENTILATION  145 

accounts  of  systems  in  actual  use,  so  that  the  reader  may  be  enabled  to 
master  the  details  for  a  similar  case  to  the  one  with  which  he  has  to  deal. 

There  is  probably  material  enough  existing  in  a  published  form  for  the 
compilation  of  a  fairly  complete  report  on  the  ventilation  of  Barracks  and 
Military  Hospitals.  The  information  is  to  be  found  in  the  '  General  Report 
of  the  Commission  on  the  Means  of  Improving  the  Sanitary  Condition  of 
Barracks  and  Hospitals,'  printed  in  the  Parliamentary  Papers  for  1801,  with 
its  Appendix,  issued  in  1863  ;  and  in  the  '  Report  of  the  Commission  on 
Barracks  and  Hospital  Improvement  and  on  the  Ventilation  of  Cavalry 
Stables  '  (1866) ;  and  further  in  the  '  Report  of  the  Commission  on  the 
Warming  and  Ventilation  of  Dwellings '  (1857);  and  in  Special  Reports 
by  F.  de  Chaumont,  General  Massy,  and  others,  published  in  the  '  Annual 
Reports  of  the  Army  Medical  Department,'  vols.  vi.  to  x. 

The  ventilation  of  Workhouses  and  Prisons  has  also  received  consider- 
able attention  and  is  referred  to  in  many  Government  publications ;  the  best 
linown  of  these  is  the  '  Report  of  the  Commission  on  the  Cubic  Space  of 
Metropohtan  Workhouses'  (1867).  An  account  of  the  arrangements  at 
Pentonville  Prison  is  given  in  the  '  Prisons  Report  for  1847.' 

Examples  of  the  ventilation  of  Prisons,  Courthouses,  and  other  build- 
ings, illustrated  by  clear  diagrams,  are  given  in  R.  Ritchie's  *  Treatise  on 
Ventilation  '  (1862).  Descriptions  are  to  be  found  in  various  books  and 
periodicals  of  arrangements  for  warming  and  ventilation  of  all  degrees  of 
complexity,  from  the  rudimentary  system  of  Gurney's  stoves  in  the  crypt  of 
St.  Paul's  Cathedral — which  suffices  for  that  building  ('  Mechanic's  Maga- 
iiine,'  vol.  Ixix.  1858,  p.  443),  to  the  most  elaborate  and  complicated  schemes. 

Taking  some  of  the  different  departments  in  order : — The  ventilation  of 
Dwelling-houses  is  the  subject  of  a  Parliamentary  Report  already  referred 
to.  One  of  its  recommendations  is  that  in  ordinary  living-rooms  ventilation 
should  be  provided  for  independently  of  the  supply  of  air  for  the  fire. 
Messrs.  Drysdale  and  Hayward  have,  in  their  book  on  '  Health  and  Comfort 
in  Housebuilding  '  (1872),  given  plans  which  they  have  found  successful 
for  supplying  houses  with  suitably  warmed  air,  and  using  the  heat  of  the 
kitchen  chimney  as  the  agent  for  the  general  ventilation  of  the  house. 
Arrangements  are  also  described  and  figured  in  a  book  by  Dr.  Griscom,  of 
New  York  (see  also  Spon's  '  Dictionary  of  Engineering,'  art.  Ventilation). 

An  account  of  the  ventilation  of  the  Lecture  Theatre  of  the  Conservatoire 
des  Arts  et  Metiers,  by  General  Morin,  is  to  be  found  in  the  '  Proceedings  of 
the  Institute  of  Mechanical  Engineers '  (1867).  In  this  the  fresh  air  is  brought 
in  at  the  ceiling  and  the  foul  air  withdrawn  through  perforations  in  the 
risers  of  the  seats.  The  elaborate  arrangements  for  the  ventilation  of  the 
Theatre  Lyrique  are  given  in  the  same  paper.  General  Morin  also  gives 
descriptions  of  the  ventilation  systems  of  many  other  buildings  in  the  works 
of  his  already  referred  to  in  this  article. 

The  ventilation  of  the  Houses  of  Parliament  has  formed  the  subject  of 
many  inquiries  and  experiments ;  it  has  been  treated  in  upwards  of  twenty 
reports  to  Parliament.^  The  original  scheme  proposed  by  Dr.  D.  B.  Reid,- 
combining  mechanical  ventilation  and  heat -suction,  seems  to  have  proved 
unsatisfactory,  partly  in  consequence  of  the  interference  with  the  original 
design,  on  account  of  misunderstandings  with  the  architect.     Subsequently, 

'  1832,  1835,  1887, 1841  (four  reports),  1843,  1846, 1847, 1848, 1852, 1854  (four  reports), 
1866,  1884,  1886  (three  reports).  The  subject  is  still  under  discussion  (see  Times,  July  25, 
1891). 

^  Report  of  the  Committee  on  the  Ventilation  of  the  Houses  ofParliament,  1835  ;  also  Pr. 
Raid's  Illustrations  of  the  Theory  and  Practice  of  Ventilation,  1844. 

VOL.    I.  Ii 


UG  HYGIENE 

Sir  G.  Guniey  introduced  the  system  of  ventilation  by  steam  jets  ;  but  in 
1866,  according  to  Dr.  Percy,  whose  report,  printed  for  the  House  of  Commons- 
(1866),  gives  a  full  description  of  the  arrangements  then  and  practically  now 
in  use,  mechanical  propulsion  had  been  entirely  abandoned,  and  the  ventila- 
tion depends  upon  heat-suction  alone,  the  air  introduced  bemg  warmed  by 
Gurney's  '  Steam  Batteries.'  The  suction  seems,  indeed,  to  have  proved  more 
than  sufficient,  for  in  1884  the  House  was  invaded  by  sewer  gas  from  a  main 
sewer  passing  under  the  building.  An  interesting  account  of  the  earher 
history  of  tnis  elaborate  series  of  experiments  in  ventilation  is  given  iu 
Ritchie's  book  already  referred  to. 

In  St.  George's  Hall,  Liverpool,  Dr.  Eeid  seems  to  have  been  able  to> 
carry  out  successfully  his  own  ideas  for  a  system  of  ventilation  by  mechani- 
cal means.  A  brief  account  of  the  arrangement  is  given  in  the  *  Journal  of 
the  Society  of  Arts,'  vol.  ii.  1853-4,  p.  757,  and  vol.  iii.  1855,  p.  379. 

The  ventilation  of  South  Kensington  Museum  is  dealt  with  in  the  Report 
of  the  Commission  on  that  building  (1869). 

One  of  the  most  recent  accounts  of  an  attempt  to  carry  out  an  elaborate 
system  of  ventilation  and  warming  is  given  by  Mr.  W.  W.  Phipson,  the 
engineer,  in  a  paper  in  the  '  Proceedings  of  the  Institute  of  Civil  Engineers,' 
vol.  Iv.  1879,  p.  124,  '  On  the  Heatmg  and  Ventilating  Apparatus  of  Glasgow 
University  :' — 

In  the  year  1864,  when  the  building  of  the  new  University  of  Glasgow  was  determined 
upon,  a  sub-committee  of  the  professors,  amongst  whom  were  Sir  William  Thomson,  Dr. 
Allen  Thomson,  Professor  H.  Blackburn,  and  the  late  Dr.  W.  J.  M.  Eankine,  considered  the 
general  principles  which  should  form  the  basis  of  the  operation  to  secure  for  the  new  build- 
ing the  most  efficient  system  of  ventilation  and  warming.  After  a  lengthened  investigation 
they  came  to  the  following  conclusions  : — • 

1.  That  the  foul  air  should  be  removed  through  outlets  as  near  as  possible  to  the 
place  where  it  is  produced,  e.g.  passages  under  desks  or  seats. 

2.  That  the  total  area  of  the  orifices  of  such  outlets  should  be  about  |  square 
foot  per  sitting,  or  28  square  inches. 

3.  That  the  total  area  of  the  orifices  of  the  inlets  for  fresh  air  should  be  about  double 
the  area  of  those  of  the  outlets  for  foul  air,  or  about  §  square  foot  per  sitting. 

4.  That  the  inlets  for  fresh  air  should  be  at  a  high  level  and  distributed  round  the  cir- 
cumference of  the  rooms. 

5.  That  fresh  air  should  be  supplied  both  hot  and  cold,  and  each  classroom  be  pro- 
vided with  means  for  mixing  it. 

6.  That  the  total  supply  of  air  to  the  classrooms  should  be  ^o  cubic  foot  per 
sitting  per  second. 

7.  That  the  sectional  area  of  the  channels  or  conduits  for  carrying  away  foul  air  should 
be  55  square  foot  per  sitting. 

8.  That  the  final  outlets  of  the  foul  air  should  be  so  placed  that  none  of  it  should  return 
to  the  buildiiig. 

9.  That  the  fresh  air  should  be  drawn  from  some  place  where  the  air  is  always  pure. 

10.  That  the  fresh  air  should  be  forced  in  by  one  or  any  required  number  of  suitable 
machines. 

11.  That  the  foul-air  conduits  should  lead  to  chimneys  in  suitable  positions  provided 
with  furnaces  capable  of  being  hghted,  the  area  of  the  furnace  grate  being  -^^  square  foot 
per  sitting. 

12.  That  the  hot  part  of  the  fresh  air  should  be  heated  by  hot-water  tubes,  and  that 
the  most  efficient  position  for  such  tubes  was  in  the  vertical  passages  in  which  the  current 
of  air  ascends. 

In  working  out  these  suggestions  it  was  found  that  the  allowance  of  i^ 
cubic  foot  of  fresh  air  per  sitting  per  second  for  classrooms  .  .  .  was  too 
much,  and  that  the  vertical  air-shafts  necessary  to  supply  this  large  volume 
of  air  assumed  such  proportions  that  the  walls  would  not  admit  of  their  con- 
struction.' It  was  therefore  altered,  but  still  the  total  volume  passing  through 
the  apparatus  was  to  be  1,800,000  cubic  feet  per  hour.     It  appears  also  that 


WARMING  AND    VENTILATION  147 

suggestion  5 — about  supplying  cold  fresh  air  as  well  as  warm,  with  pro- 
vision for  mixing — was  also  abandoned. 

In  this  paper  and  the  discussions  following  it,  which  occupied  two  evenings, 
a  good  deal  of  light  is  thrown  upon  the  whole  question.  Incidentally 
accounts  are  given  of  the  ventilation  of  the  Free  Trade  Hall  and  Boyal 
Exchange,  Manchester,  by  Mr.  Constantine. 

An  abstract  of  the  account  of  the  arrangements  for  the  Vienna  Opera  House, 
from  the  Proceedings  of  the  '  Soci6t6  des  Ingenieurs-civils,'  1880,  p.  431,  is 
given  in  the  'Proc.  Inst.  C.E.' vol.  Ixiv.  p.  450,  and  also  of  those  of  the 
Bourse  in  Berlin,  ibid.  vol.  Ixxi.  p.  522.  In  this  connexion  we  may  also 
refer  to  a  paper  by  the  late  Eobert  Briggs,  '  On  the  Ventilation  of  Halls  of 
Audience,'  *  Trans.  Amer.  Soc.  G.E.'  vol.  x.  1881,  p.  53. 

For  the  description  of  the  ventilation  of  Hospitals  the  reader  maybe 
referred  to  the  article  on  Ventilation  in  Spon's  '  Dictionary  of  Engineering.' 
General  Morin  gives  an  account  of  the  ventilation  of  Guy's  Hospital  (built  by 
Rhode  Hawkins)  and  of  other  hospitals  in  vol.  i.  of  his  '  Etudes  sur  la  Venti- 
lation,' p.  34,  and  of  the  Hopital  Lariboisiere,  in  the  same  volume,  p.  356,  with 
full  detail,  and  an  investigation  cf  the  action.  The  system  is  based  on  the 
injection  of  air  by  fans.  Dr.  Arnott  ventilated  the  hospital  at  York  by  pumps 
of  his  own  design,  worked  by  water  power  (see  Arnott,  '  On  the  Smokeless 
Fireplace '  &e.  or  Ritchie's  '  Treatise  on  Ventilation '). 

On  the  general  principles  of  the  ventilation  of  hospitals,  there  is  a  useful 
article  in  '  Fraser's  Magazine  '  for  November  1875. 

Other  departments  of  the  subject  are  of  a  more  technical  nature.  The 
ventilation  of  ships  has  received  a  good  deal  of  attention,  since  Dr.  Arnott 
made  a  report  to  the  General  Board  of  Health  on  the  subject,  which  is  con- 
tained in  their  reports  on  Quarantine,  1849-54.  The  modern  development  of 
this  department  for  the  cooling  of  ships  &c.  by  mechanically  cooled  air  is 
fully  treated  in  a  paper  by  J.  J.  Coleman  on  Air-refrigerating  Machinery 
('Proc.  Inst.  C.E.'  vol.  Ixviii.  p.  146)  and  the  discussion  upon  it. 

For  information  as  to  the  ventilation  of  mines  and  tunnels,  the  technical 
journals  must  be  referred  to.  For  the  former  the  ventilating  fan  seems  to  be 
coming  more  into  use,  and  very  large  machinery  is  being  employed  for  the 
purpose.  Mechanical  ventilators  are  now  made  to  deliver  100,000  to  250,000 
cubic  feet  of  air  per  minute  ;  the  Guibal  fan  is  made  up  to  50  feet  in  diameter, 
the  Waddell  fan  up  to  45  ft.,  while  the  quicker  moving  Schiele  fan  reaches 
15  ft.  This  subject  is  considered  in  the  work  of  M.  Murgue,  to  which  reference 
has  already  been  made,^  and  is  also  discussed  in  the  '  Proceedings  of  Inst,  of 
Mech,  Eng.'  1875,  p.  317,  by  W.  Daniel. 

It  appears  from  the  '  Proceedings  of  the  Institution  of  Civil  Engineers  '  that 
the  ventilation  of  underground  railways  sometimes  receives  a  certain  amount 
of  attention.  Exceptional  cases  of  ventilation  occasionally  require  treatment, 
which  is  noticed  from  time  to  time  (see,  for  example,  '  Electrician,'  Feb.  22, 
1889,  p.  452). 

The  ventilation  of  sewers  is  a  special  department  (see  '  Annual  Reports, 
Metropolitan  Board  of  Works,'  1866-68-73). 

A  number  of  contrivances  have  been  devised  for  the  ventilation  of  railway 
carriages  without  draughts,  but  so  far  their  success  does  not  seem  to  be 
sufficiently  conspicuous  for  their  general  adoption. 

A  general  summary  of  the  special  points  to  be  considered  in  the  ventila- 
tion of  buildings  of  special  character  is  given  by  General  Morin,  '  Manuel,' 
§  163  et  seq. 

'  See  also  Ee;ports  on  the  Ventilation  of  Mines,  Parliamentary  Beports,  1850 ;  Proc. 
Inst.  Mech.  Eng.  1877,  p.  92  ;  Proc.  Inst.  C.E.  xliv.  p.  18,  Ixii.  p.  396,  xci.  p.  541. 

L  2 


148  HYGIENE 

Taking  all  the  points  into  consideration,  it  will  be  seen  that  although 
great  progress  has  been  made  of  late  years  towards  the  satisfactory  solution 
of  the  problem  of  combined  warming  and  ventilation,  especially  by  the 
development  of  the  mechanical  system,  we  are  still  unable  to  regard  the 
question  as  definitely  settled.  The  most  important  point  is  that  the  pre- 
scribed amount  of  air  for  adequate  ventilation  (p.  11 G)  is  greater  than  can  be 
supplied  without  very  great  extension  of  systems  hitherto  adopted.  For 
crowded  rooms  m  particular  the  areas  of  inlets  and  outlets  would  require  to 
be  enormous,  and  the  maintenance  of  the  flow  would  necessitate  very  exten- 
sive machinery.  But,  provided  that  those  interested  are  willing  to  pay  the 
price,  the  difficulties  could  no  doubt  be  overcome.  It  is  to  be  remarked  that 
at  present  very  little  is  accurately  known,  and  very  little  account  is  taken 
of  the  local  circulation  of  air  in  a  large  room,  and  so  no  advantage  is  con- 
sciously taken  of  this  circulation  in  the  provisions  for  ventilation.  It  would 
seem  to  be  possible  by  a  more  accurate  study  of  the  distribution  of  the 
currents  of  air  in  a  large  room  to  remove  the  fouler  portion  of  it  more  directly, 
and  thus  prevent  its  mixing  with  the  purer  portion,  and  so  to  reduce  the 
amoiuit  of  fresh  air  necessary. 

Hitherto  attention  has  been  directed  to  this  branch  of  the  subject,  mainly 
with  the  important  object  of  avoiding  draughts,  and  some  measure  of  success 
lias  been  attained;  but  when  the  necessary  conditions  for  securing  that  object 
have  been  formulated  and  clearly  understood,  the  next  step  may  well  be  to 
direct  the  air  supply  with  a  view  to  its  economy  in  comparison  with  its  useful 
efi'ect. 

The  economy  of  cost  of  heating,  as  well  as  the  efficiency  of  ventilation, 
also  depends  largely  upon  this  element,  and  for  securing  the  same  object 
more  accurate  knowledge  of  the  magnitude  of  the  air  currents  in  ducts  and 
the  resistances  of  the  ducts  would  render  valuable  aid,  so  that  we  look  to  the 
numerical  expression  of  the  details  of  circulations,  both  general  and  local,  to 
provide  the  means  of  further  progress. 


METEOROLOGY 


BY 

G.   J.   SYMONS,    F.E.S. 

SECRETARY       ROYAL       METEOROLOGICAL       SOCIETY 


INTEODUCTOEY 

Thirty  years  ago  it  would  perhaps  have  been  well  to  commence  this  section 
by  demonstrating  the  relation  between  Meteorology  and  Public  Health,  but 
the  necessity  has  rapidly  diminished  until  now  one  sentence,  just  as  a 
reminder,  is  all  that  can  be  required. 

I  have  said  thirty  years,  but  might  almost  as  well  have  said  ninety,  for 
as  far  back  as  1796  Dr.  William  Heberden,  F.E.S.,  submitted  a  paper  to  the 
Eoyal  Society,  '  Of  the  Influence  of  Cold  on  the  Health  of  the  Inhabitants  of 
London,'  and  hterature  of  that  class  has  gradually  increased  until  it  fills 
many  shelves.  One  cannot  take  up  the  Eeports  of  the  Eegistrar-Generals,  of 
the  Army  Medical  Department,  or  of  the  majority  of  the  Medical  Officers  of 
Health,  and  of  the  Superintendents  of  our  County  Lunatic  Asylums,  without 
•coming  upon  masses  of  meteorological  data.  Medical  men,  like  Acland, 
Ballard,  Mitchell,  Moffat,  Scoresby-Jackson,  Shapter,  Tripe,  and  scores  of 
'Others,  have  discussed  the  relation  of  the  two  subjects.  It  is  not  for  me  to 
follow  in  their  path,  or  review  their  work,  but  to  explain  as  clearly  as  possible 
the  construction  and  use  of  the  various  instruments  employed  by  meteorolo- 
gists, what  are  the  good  and  the  bad  features  of  each,  how  they  are  to  be 
placed,  when  they  are  to  be  read,  how  the  observations  are  to  be  entered,  and 
.how  they  shotild  be  worked  up  and  presented  to  the  public. 

ATMOSPHEEIC  PEESSUEE 

It  is  not  very  easy  to  explain  why  it  is  an  almost  invariable  rule  that 
when  the  numerous  branches  of  meteorology  have  to  be  treated  of,  the  baro- 
.meter  takes  precedence  over  the  thermometer.  It  is  beyond  the  province  of 
"this  section  to  consider  the  effect  of  varia.tions  of  atmospheric  pressure  upon 
the  human  frame  ;  ^  we  have  here  to  consider  (1)  how  atmospheric  pressure  is 
measured,  (2)  what  are  the  variations  in  its  amount.  Barometers  may  be 
roughly  divided  into  two  groups,  those  in  which  the  pressure  of  the  atmo- 
sphere is  indicated  by  the  length  of  the  column  of  fluid  (be  it  water,  glycerine, 
or  mercury)  which  it  will  support,  or  by  the  pressure  which  it  exerts  on  the 
sides  of  a  box  which  has  been  nearly  exhausted  of  air,  and  then  hermetically 
sealed.  It  is  unnecessary  here  to  deal  with  so  elementary  a  matter  as  the 
principle  of  the  barometer,  but  in  explaming  how  to  transport,  erect,  and  read 
a  thoroughly  good  mercurial  barometer,  most  of  the  essential  features  will  be 
incidentally  mentioned.  Nor  is  it  necessary  to  spend  time  in  specifying  the 
faults  of  old  patterns — a  wheel  barometer  may  be  ornamental  in  a  hall,  may 
even  sometimes  induce  one  to  take  an  umbrella,  but  is  absolutely  useless  as 
a  scientific  instrument.  For  absolute  accuracy  there  are  two  excellent  pat- 
terns represented  in  figs.  53  and  54.  Fig.  53  represents  a  standard  barometer 
>of  the  type  introduced  at  the  beginning  of  this  century  by  a  Frenchman,  M. 
Fortin.  The  enlarged  sketch,  fig.  55,  illustrates  the  special  merit  of  this 
.pattern.     A  moment's  consideration  wiU  convince  anyone  that  with  a  verti- 

'  Eeference  to  La  Pression  Barom6triqi.ie,  by  Paul  Bert  (Paris,  1858),  may,  however,  be 
■permitted. 


152 


HYGIENE 


cal  tube  and  a  cistern  of  mercury  at  the  bottom,  a  fall  of  the  barometric? 
column  must  produce  a  rise  in  the  cistern,  and  vice  versa.  If  then  the  scale 
of  inches  on  the  upper  part  of  the  instrument  be  laid  off  from  a  zero  at  any 
fixed  point  in  the  cistern,  the  barometer  will  read  wrongly  at  every  point  but 

one  ;  its  motions  will  always   be   too 
small  in  the  ratio  which  the  area  of  the 
cistern  bears  to  the  area  of  the  tube. 
In  the  Fortin  barometer  this  error  is 
removed  by  laying  off  the  scale  from 
the  extremity  of  the  ivory  point,  above 
A,  fig.  55,  and  by,  at  each  observation, 
so  turning  the  screw  at  B  that  the  mer- 
cury in  the  cistern  is  exactly  in  contact 
with  that  extremity  of  the  ivory  point. 
The  other  way  of  re- 
moving the  difficulty 
is  that  shown  in  fig. 
54,  the  so-called  Kew 
pattern  barometer,  in 
which  the  cistern  is 
closed  (except  as  re- 
gards a  wooden  air 
inlet)    and,  its   area 
having    been    accu- 
rately     determined, 
the    inches    on   the 
scale    are    not    real 
inches,    but    inches 
of  pressure,  i.e.  true 
inches  so   shortened 
as  to  compensate  for 
the  rise  of  the  mer- 
cury in  the  cistern. 
It  may  be  well    to 
point  out  the  merits 
and  demerits  of  each 
of     these    patterns. 
The    Fortin    is    the 
more  difficult  to  make,  and  is  therefore 
the  more  costly  of  the  two,  and  the 
adjustment  of  the  mercury  to  the  ivory 
point  requires  care  ;  on  the  other  hand, 
.it  has  two,  if  not  more,  great  advan- 
tages ;  (1)  the  mercury  can  be  screwed 
up  so  as  to  entirely  fill  the  tube,  and  it 
then  travels  with  less  risk  than  if  the 
tube  be  not  full ;  (2)  as  long  as  the  tube 
is  not  broken,  and  does  not  contain  air, 


Fig.  53. 


Fig.  54. 


and  there  is  mercury  enough  to  fill  the 
cistern  up  to  the  ivory  point,  the  reading  must  be  correct.  The  Kew  pattern 
is  lower  in  price  and  easier  to  observe,  it  is  not  so  sensitive  as  a  Fortin, 
because  it  is  necessary  to  contract  the  tube,  and  if  mercury  escapes  from  the 
inner  cistern  the  observer  may  continue  to  record  the  readings  unconscious 
that  they  have  thereby  become  worthless. 


METEOBOLOGY  15a 

As  regards  the  transport  of  barometers  there  is  always  great  difficulty. 
The  Fortin  barometers  should  be  so  screwed  up  that  the  mercury  rests  steadily 
against  the  top  of  the  tube,  but  this  screwing  up  must  not  be  done  recklessly 
or  the  top  of  the  tube  may  be  knocked  out  by  the  mercury  (for  being  a  nearly 
perfect  vacuum  the  mercury  hits  it  like  a  pneumatic  hammer),  or  the  mercury 
may  be  squeezed  through  the  pores  of  the  leather  bag,  or  even  the  bag  itself 
burst.  After  being  well  screwed  up,  the  barometer  should  be  turned  cistern 
uppermost,  and  if  possible  carried  to  its  destination  in  that  position.  If  this 
cannot  be  done  it  must  be  arranged  to  travel  quite  flat,  and  if  practicable  trans- 
versely to  the  direction  of  motion — e.g.  in  a  gig,  a  barometer  will  travel 
better  lying  in  the  direction  of  the  axle,  than  in  that  of  the  shafts.  A  broken 
barometer  is  not  worth  much  more  than  a  third  of  a  sound  one,  hence  it  is 
true  economy  to  spend  a  little  extra  for  additional  packing.  The  Kew 
pattern  barometers  are  said  to  travel  best  lying  flat. 

On  receipt  of  a  barometer,  the  first  thing  is  to  select  a  good  position.  It 
should  be  one  on  which  the  sun  rarely  shines,  and  yet  which  has  a  good  light, 
indoors,  and  where  it  is  not  likely  to  be  interfered  with.  The  Bl-inch  line 
should  be  at  the  level  of  the  observer's  eye ;  if  the  barometer  be  a  Fortin, 
this  should  be  rather  higher,  e.g.  by  using  a  stool,  than  for  a  Kew  pattern, 
because  with  the  Fortin  it  is  also  necessary  that  the  observer  see  comfortably 
the  ivory  point  in  the  cistern.  On  opening  the  case,  the  barometer  itself  will 
be  found  packed  separately  from  the  board  on  which  it  is  to  be  suspended  ; 
this  board  should  be  firmly  fixed  in  position,  and  then  the  barometer  should 
be  hung  on  it.  Before  actually  fixing  the  barometer,  it  will  be  well  to  turn 
it  cistern  downwards,  and  slightly  unscrew  the  cistern  so  as  to  let  the  mer- 
cury down  an  inch  or  two,  then  incline  the  barometer  gently  so  that  the 
mercury  may  run  up  to  the  top  of  the  tube.  It  ought  to  elicit  a  sharp  me- 
tallic click,  but  it  may  give  only  a  dull  thud ;  if  on  two  or  three  trials  it  always 
gives  a  dull  sound,  it  is  because  air  has  got  into  the  tube  and  forms  a  cushion 
at  the  top.  It  is  usually  not  difficult  to  remove  the  air  in  the  following 
manner.  Screw  the  mercury  up  until  it  is  within  about  half  an  inch  of  the  top 
of  the  tube,  turn  the  barometer  gently  cistern  uppermost,  and  tap  the  top  of 
it  on  a  thick  rug,  or  on  the  toe  of  a  boot  for  five  minutes,  then  screw  the 
mercury  as  tight  as  can  be  done  without  exerting  strength  enough  to  force 
any  mercury  through  the  wash-leather  bag,  turn  the  barometer  cistern  down- 
wards, release  the  mercury  and  try  whether  the  tap  is  not  then  clear  and 
sharp.  In  all  probability  it  will  be,  for  the  air  has  been  gradually  tapped 
out  of  the  tube  ;  if  it  is  not  gone,  the  process  must  be  repeated  either  for  a 
longer  time,  or  with  somewhat  stronger  taps. 

At  the  bottom  of  the  board  will  be  found  a  ring  with  three  adjusting^ 
screws.  These  should  be  nearly  withdrawn,  the  barometer  left  free  to  assume 
a  vertical  position  in  the  ring,  and  then  the  screws  gradually  turned  in  mitil 
they  press  upon  it.  Care  must  be  taken  that  the  screws  are  not  turned  after 
they  are  in  contact  with  the  barometer,  or  their  pressure  will  prevent  its 
remaining  perpendicular,  and  then  it  will  read  too  high. 

Assuming  the  barometer  free  from  air,  and  duly  suspended,  the  next  thing 
is  to  read  it.  In  the  Fortin  pattern  the  first  matter  to  attend  to  is  the 
cistern  :  the  mercury  must  be  let  down  until  its  level  just  touches  the  tip  of 
the  ivory  point ;  the  best  plan  is  to  lower  it  rather  too  far,  and  then  raise  it 
slowly  till  it  just  touches. 

Now  we  have  to  deal  with  the  reading — by  no  means  a  comphcated 
matter,  but  perhaps  the  most  so  of  anything  that  a  meteorological  observer 
has  to  do.  The  first  process  is  very  easy  :  the  observer  has  only  to  turn  the 
screw  of  the  vernier  until  he  produces  the  state  of  things  represented  in 


154 


HYGIENE 


fig.  5G — i.e.  his  eye,  the  front  of  the  vernier,  the  summit  of  the  mercurial 
column,  and  the  back  of  the  vernier  all  in  one  straight  line.  The  second 
stage  is  to  some  persons  a  puzzle.  The  principle  of  the  vernier- — or  nonius, 
as  it  used  to  be  called — is  the  very  simple  one  that  if  you  put  side  by  side 
two  scales,  on  one  of  which  a  given  length  is  divided  into  ten  parts,  and  on 

the  other  into  nine,  the  top  and  bottom  lines 
will  coincide,  but  the  intermediate  ones  will  each 
be  one-tenth  higher  than  those  on  the  first  scale ; 
and  so  small  excesses  can  be  easily  measured. 
Fig.  57  gives  the  vernier  of  a  Fortin  barometer 
in  two  positions  :  in  A  we  see  that  the  mercury 

1^ is  slightly  above  29-6  ;  this  can  be  seen  from 
the  fixed  scale  ;  the  line  with  the  arrowhead  is 
29^ — i.e.  29'5  ;  each  of  the  long  lines  on  the 
scale  is  '1,  and  the  short  ones  '05  ;  the  mercury 
is  not  only  above  29'5  but  above  29'55  (the  first 
short  line  above  29/^),  and  it  is  above  the  long 
line,  and  therefore  above  29"G — it  remains  to 
see  how  much.  In  using  the  vernier  the  first  thing  is  to  decide  which  line 
on  the  movable  scale  is  level  with  one  on  the  fixed  one  ;  evidently  it  is  the 
third  line  above  the  figure  1  on  the  movable  scale.  We  have  only  to  read 
that  and  add  it  to  the  29"6  and  all  is  finished.     Now  the  first  rule  is  that 

the  figures  on  the  movable  scale  are 
hundredths  of  an  inch  ;  therefore  if  the 
line  marked  1  had  been  level  with  a  line 
on  the  fixed  scale  one  hundredth  woiild 
have  had  to  be  added  to  29'6 — i.e. 

29-60 
•01 


29-61 


would  have  been  the  reading  ;  but  the 
line  which  cuts  is  three  higher,  and  as 
each  of  these  unnumbered  lines  repre- 
sents y-j^ths,  we  have  -002  x  3  =  -006 
above  the  "01 — i.e.  -016  to  add  to  the 
29-6,  and  so  it  comes  out  29-616.  To 
make  the  matter  quite  clear,  example 
B  is  given.  Here  the  mercury  is  above 
29  inches,  and  shghtly  above  29-05  (the 
first  short  line) ;  looking  up  the  vernier 
we  see  that  the  line  which  cuts  is  the 
fourth,  then  -002  x  4  =  -008,  which, 
added  to  29-05,  makes  29-058  inches. 

Assuming  that  the  observer  has 
thoroughly  mastered  the  vernier,  and 
the  mode  of  setting  it  to  the  top  of  the 
column,  we  may  now  say  a  few  words  as 
to  the  routine  of  taking  a  reading  with 
a  Fortin:  (1)  read  the  attached  thermometer  to  the  nearest  whole  degree, 
and  enter  it ;  (2)  lower  the  mercury  in  the  cistern  until  it  is  quite  clear  of  the 
ivory  point,  and  then  raise  it  gently  until  it  just  touches  it ;  (3)  bring  the 
vernier  to  its  true  position  ;  (4)  read  off  and  enter  the  reading  ;  (5)  it  is  well, 
but  not  indispensable,  to  lower  the  mercury  in  the  cistern,  so  that  it  does 


29.61G. 


29-058. 


Fig.  57. 


METEOBOLOGY 


155 


not  remain  in,  or  liable  to,  contact  with  the  ivory  point,  as  oxidation  of  the 
surface  is  hastened  by  such  contact. 

With  a  Kew  pattern  barometer  the  routine  is  the  same  except  that  (2) 
and  (5)  have  not  to  be  done. 

There  are  three  corrections  which  have  to  be  applied  to  barometric 
readings ;  (1)  index  error,  in  which  the  effect  of  capillarity  is  now  usually 
included;  (2)  temperature  ;  (3)  altitude. 

Index  error  is  usually  very  small,  and  is  generally  the  same  at  all  parts 
of  the  barometric  scale.  It  is  determined  at  the  central  observatory  in  each 
country  and  its  amount  entered  on  the  certificate  sent  with  the  barometer. 

TemperaUire. — If  two  barometers  are  in  two  adjoining  rooms  at  the 
same  level,  but  the  one  room  is  warm  and  the  other  cold,  the  barometers 
will  differ,  because  in  the  warmer  room  the  mercury  has  dilated  and  has 
therefore  become  of  less  specific  gravity,  so  that  in  the  warm  room  the 
barometer  Avill  read  the  higher.  And  the  matter  is  further  complicated  by  the 
fact  that  the  inches  on  the  brass  scale  also  vary  in  length  according  to  tem- 
perature, and  are  of  their  proper  length  only  at  62°  F.  We  do  not  employ 
barometers  to  tell  us  temperature  but  pressure,  therefore  it  has  long  been 
agreed  throughout  all  nations  that  barometer  readings  shall  be  reduced  to 
what  they  would  have  been  had  both  the  mercury  and  the  brass  scale  been 
at  32°  F. 

For  barometers  made  (as  all  good  ones  are)  with  brass  scales  the  cor- 
rections are  as  under  : — 


Temp. 

27  inches 

28  inclies 

29  inches 

30  inches 

31  inches 

30 

-■004 

-•004 

-•004 

-  ^004 

-•004 

40 

-•028 

-•029 

-•030 

-•031 

-•032 

50 

-•052 

-•054 

-•056 

-•058 

-•060 

60 

-076 

-•079 

-•082 

-■085 

-•087 

70 

-•100 

-•104 

-•108 

-•111 

-•115 

80 

-•124 

-•129 

-•133 

-•138 

-•143 

90 

-•148 

-•153 

-•159 

-•164 

-•170 

100 

-•172 

-•178 

-•184 

-•191 

-•197 

Detailed  tables  giving  the  values  for  each  degree  F.  and  for  each  half- 
inch  of  the  barometer  will  be  found  in  Guyot,  Hazen,  Marriott,  Scott,  and 
several  other  works. 


ANEEOIDS 

Aneroids  should  never  be  relied  upon  for  fixed  stations  ;  they  are  extremely 
useful  instruments,  and  for  some  purposes  invaluable ;  but  after  working 
well  for  periods,  which  may  be  a  week,  or  may  be  twenty  years,  they  will 
occasionally  go  hopelessly  wrong.  Checked,  however,  from  time  to  time 
against  a  mercurial  standard,  an  aneroid  is,  as  a  measurer  of  altitude,  in- 
valuable. The  principle  of  the  aneroid  is  very  simple.  Suppose  two  saucers 
made  of  corrugated  iron,  turned  face  to  face,  and  soldered  round  the  rim, 
and  that  by  a  small  tube  the  air  was  exhausted  from  the  interior,  and  the 
tube  then  closed,  it  is  evident  that  the  two  sides  of  this  corrugated  flat  box 
would  be  forced  together  by  the  pressure  of  the  atmosphere,  and  that  the 
compression  would  be  equal  to  the  equilibrium  between  the  strength  of  the 
box  and  the  pressure  of  the  atmosphere  ;  therefore,  the  greater  the  atmo- 
spheric pressure,  the  closer  will  the  sides  be  squeezed  together.  This  motion 
is,  by  suitable  levers,  made  to  turn  the  hand  on  the  face  of  the  aneroid.  An 
aneroid  should  always  be  read  in  one  position,  not  sometimes  hanging  on  a 
nail  and  sometimes  lying  on  a  table. 


156 


HYGIENE 


EECOEDING  BAEOMETER 

There  are  many  modes  whereby  barometers  have  been  so  arranged  as  to 
produce  automatically  a  pencil,  ink,  or  photographic  record  of  the  changes 
in  the  pressure  of  the  atmosphere  Most  of  these  are  too  elaborate  and 
costly  for  employment  except  in  observatories,  and  therefore  do  not  need 
mention  here.  But  one  very  cheap  and  ingenious  pattern  has  been  brought 
out  recently  by  MM.  Richaid  Freres  of  Paris,  to  which  a  few  lines  may  be 
devoted.  Power  is  obtained  from  s  series  of  aneroid  vacuum  boxes,  the  motion 
of  which  is  multiplied  by  a  long  lever.  The  end  of  this  lever  carries  a  very 
small  triangular  box  (the  pen)  filled  with  ink,  which  presses  lightly  against 
the  paper-covered  cylinder.  Once  a  week  a  clock  contained  in  this  cylinder 
is  wound  up,  and  a  new  sheet  of  paper  put  on  the  cylinder,  the  pen  on 
the  extremity  of  the  lever  is  provided  with  fresh  ink  (glycerine  and  a  little 
aniline  ink),  and  then,  as  the  cylinder  is  rotated  by  the  clock  contained  within 


Fig.  58. 


it,  and  the  lever  is  higher  or  lower  as  the  barometer  is  higher  or  lower,  a 
very  clear  continuous  ink  record  is  produced.  In  fig.  58  the  pen  is  at  7  p.m. 
on  a  Wednesday  and  the  pressure  is  768  milhmetres  or  30-28  inches.  Papers 
can  be  had  ruled  to  either  metrical  or  English  scale. 

As  has  already  been  pointed  out,  aneroids  such  as  this  cannot  be  reHed 
upon  as  certain  to  give  absolute  accuracy,  but  checked  from  time  to  time 
against  a  mercurial  standard  they  are  most  useful,  and  the  diagrams  are  very 
interesting. 

MEASUEEMENT   OF  HEIGHTS 

It  would  be  beyond  our  hmits  to  give  elaborate  rules  and  formulae  for  the 
barometric  measurement  of  altitudes,  but  it  may  be  convenient  to  give 
sufficient  simple  ones  to  enable  any  one  to  form  (e.g.)  a  rough  idea  as  to 
whether  a  spring  in  one  valley  could  be  utilised  in  another.  It  is  imma- 
terial whether  an  aneroid  or  a  mercurial  barometer  be  used ;  in  either  case 
the  barometer  should  be  read  three  times.     Suppose  that  it  is  required  to 


METEOBOLOGY 


157 


know  the  height  of  A  above  B.  Eead  the  barometer  at  A,  take  it  to  B,  read 
it  there,  go  back  to  A  and  read  it  the  third  time.  Suppose  the  readings 
to  be 

in.  in. 

A  (1st  time)   30-10        B  20-90 
A  (2nd  time)  30-14 
Then  take  the  mean  at  A=30-12 
„     reading  at  B=29-90 

Difference        '22  inch. 

The  simplest  rule  is,  move  the 
decimal  two  places  to  the  right  and 
multiply  the  difference  by  9,  thus : 
•22 
9 

198= difference  in  feet. 


23 


S*     23 


24 


iS!      25 


2G 


27 


28 


29 


■      30 


A  closer  approach  to  the  truth  g   26 

can  be  obtained  with   great   ease  ^    27 

by  means  of  the  annexed  diagram,^  | 

and    attending    to  the   following  28 

rules — (1)  Find  the  mean  pressure  ^9 
at  the  two  stations  ;  in  the  above 

example  80:^+25:5?=80-01.  (2)  » 

^  31 

Find  (or  estimate)  the  mean  tem- 
perature ;  suppose  it  to  be  70°.  (3) 
Look  in  the  diagram  where  the  line 
for  30  inches  crosses  that  for  70°, 
and  read  off  the  slanting  value  for 

that  point ;  it  will  be  seen  to  be  the  dotted  line  for  9^  or  9*5  that'll  the  multi- 
plier to  be  used,  and  so  we  get 

•22 

9-5 


30°    40°    50°    60°    70°    80° 
Mean  Temperature. 
Fig.  59. 


110 

198 


209-0,  or  209  ft.  instead  of  198  ft.  as  by 
the  simpler  rule. 

Eeference  to  the  diagram  will  show  that  9  would  have  been  absolutely 
right  at  a  temperature  of  45°,  and  that  the  multiplier  rises  with  the  tem- 
perature. 

EEDUCTION   OF  BAKOMETER  TO   SEA-LEVEL 

For  sanitary  purposes  we  advise  that  this  be  never  done  ;  it  is  obviously 
of  no  medical  or  sanitary  importance  to  a  resident  at  Buxton  to  know  what 
the  pressure  of  the  barometer  would  be  if  he  dug  a  well  1,000  feet  deep  and 
went  to  the  bottom  of  it.  Eeduction  to  sea-level  is  a  necessity  to  the 
meteorologist,  but  not  to  the  climatologist  or  the  student  of  liygiene.  If 
either  of  them  wishes  to  apply  the  correction  accurately,  he  can  consult 
Guyot's,  Marriott's,  or  Scott's  tables;  if  he  wishes  to  know  it  approximately, 
he  can  for  small  elevations  add  one-tenth  of  an  inch  for  each  hundred  feet. 


»  From  Pocket  Meteorological  Tables.     By  G.  J.  Symoiis. 


158  HYGIENE 


DAILY  EANGE  OF  THE  BAROMETER 

In  most  parts  of  tlie  world  the  barometer  has  daily  a  double  tide,  rising 
to  maxima  about  10  a.m.  and  10  p.m.  and  falling  to  minima  about  4  a.bi.  and 
4  P.M.,  but  the  amount  of  these  fluctuations  is  small,  and  I  am  not  aware  that 
it  has  ever  been  suggested  that  they  in  any  way  affect  public  or  individual 
health. 

EXTREMES   OF   PRESSURE 

At  the  level  of  the  sea  the  average  pressure  may  be  put  at  30  inches,  and 
the  variations  at  from  27  inches  as  the  minimum  to  31  inches  as  the  maximum. 
When  I  mention  that  in  his  memorable  Wolverhampton  ascent  Mr.  Glaisher 
went  so  high  that  the  pressure  fell  to  less  than  8  inches,  and  that  in  the 
caisson  for  the  great  Forth  Bridge  the  men  worked  in  a  chamber  so  far  under 
water  that  the  barometer  stood  at  72  inches,  it  will  be  seen  how  great  is  the 
range  which  the  human  frame  can  sustain  and  how  insignificant  as  compared 
with  it  are  the  atmospheric  fluctuations  of  4  inches — 4  against  04. 


TEMPERATURE 

A  few  prefatory  remarks  on  thermometers  in  general  will  probably  not 
be  superfluous,  as  few  persons  know  the  reasons  for  the  very  different  patterns 
of  thermometer,  or  how  to  select  that  best  adapted  for  the  object  which  they 
have  in  view.  It  is  very  difficult  to  compress  within  any  reasonable  limit 
all  that  ought  to  be  said  upon  the  subject,  and  therefore  my  remarks  must  of 
necessity  be  somewhat  curt.  Thermometers  may  be  classified  as  Ordinary,. 
Registering,  and  Recording. 

Ordinary  Thermometers 

In  early  days  these  consisted  of  glass  tubes  filled  with  alcohol  or  mercury^ 
tied  with  wire  to  slabs  of  wood  or  of  ivory,  on  which  the  divisions  were  marked ; 
the  bulbs  were  large  and  the  glass  was  often  very  thick.  Alcohol  (and  other 
liquids)  proving  inferior  to  mercury,  the  latter  is  now  in  good  instruments 
alone  employed  (except,  as  will  be  noted  presently,  under  the  head  of  register- 
ing thermometers)  ;  the  bulbs  are  thin  and  much  smaller,  because  opticians 
have  learned  how  to  make  the  bore  of  the  tubes  oval,  and  to  mount  them 
with  the  broad  side  of  the  tube  foremost.  This  gives  an  appearance  of  breadth 
to  the  column,  and  therefore  makes  it  easily  seen,  while  the  smallness  of  the 
bore  enables  the  size  of  the  bulb  to  be  reduced,  and  the  smaller  the  bulb  the 
more  sensitive  the  thermometer.  If  a  large  bulb  be  indispensable  it  is  best 
made  as  a  cylinder,  not  as  a  sphere,  because  a  cylinder  exposes  more  surface, 
and  therefore  takes  up  the  temperature  more  rapidly.  Another  great  improve- 
ment, which  we  believe  was  due  to  Messrs.  Negretti  and  Zambra  of  London,. 
is  the  working  into  the  tube  of  a  layer  of  opal  glass.  This  (which  is  called 
enamelling)  white  background  throws  up  the  thread  of  mercury,  and  has  done 
more  than  anything  else  to  enable  thermometers  to  be  made  with  small,  and 
therefore,  very  sensitive  bulbs.  Again,  now,  all  good  thermometers  have  the 
scale  etched  on  the  tube,  which  (1)  lasts  as  long  as  the  thermometer  itself,, 
instead  of  perishing  as  did  the  old  wood  and  ivory  ones  ;  (2)  which  cannot 
slip  about  as  did  the  old  frames  ;  (3)  which  avoids  parallax  by  bringing  the 
division  as  close  as  possible  to  the  mercurial  column.     For  ordinary  house  or 


METEOROLOGY  159 

hospital  use,  glass  or  porcelain  slabs  to  carry  and  protect  the  thermometer 
are  the  cleanest  and  most  permanent ;  glass  is  better  than  porcelain  because 
sometimes  moisture  penetrates  the  glaze  of  the  latter,  and,  freeziugunderneath, 
splits  off  flakes  of  the  porcelain,  disfiguring,  if  not  ruining,  the  instrument. 
This  evil  seems,  however,  to  be  decreasing,  owing  probably  to  improved 
manufacture.  There  is  a  notable  difference  between  British  and  Continental 
makers  as  regards  the  mounting  of  thermometers,  and  probably  (as  is  fre- 
quently the  case)  something  between  the  extremes  is  best.  Continental 
makers  of  high-class  thermometers  seem  to  consider  that  the  tube  should 
have  no  mounting  whatever  ;  they  form  a  loop  in  the  glass  of  the  end  of  the 
stem  and  consider  the  instrument  complete.  An  English  maker,  on  the 
contrary,  nearly  buries  his  tube  in  a  wood,  glass,  or  zinc  mounting.  Each 
has  a  good  feature,  and  each  a  bad  one.  The  Continental  plan  leaves  the 
thermometer  free  to  assume  the  temperature  of  air,  or  of  any  body  in  which 
it  is  immersed,  but  it  leaves  the  tube  very  fragile.  The  English  plan  protects 
the  tube  from  breakage,  but  not  infrequently  so  surrounds  the  bulb  as  to  cause 
it  to  show  a  temperature  intermediate  between  that  of  the  slab  to  which  it  is 
attached  and  that  of  the  air  or  other  surrounding  medium. 

Thermometers  can  now  be  had  of  almost  any  degree  of  minuteness  or 
delicacy  which  can  be  imagined.  I  have  seen  some  with  their  tiny  bulbs 
inside  the  green  shoots  of  growing  plants  ;  others  with  cylindrical  bulbs 
coiled  flat  like  a  snake,  with  the  scale  rising  perpendicularly  from  the  centre, 
the  coiled  bulb  not  so  large  as  a  shilling,  being  for  taking  local  temperatures, 
and  the  scale,  perhaps  1\  inch  long,  for  reading  them  off.  And  the  accuracy 
of  thermometers  is  now  very  remarkable,  pro\dded  that  nothing  unreasonable 
be  expected  of  the  makers.  Some  persons  imagine  that  an  accurate  thermo- 
meter can  be  made  of  any  required  pattern  as  quickly  as  a  coat.  This  is 
impossible,  and  a  thermometer  made  in  a  liurry  generally  proves  a  bad  one. 
Until  within  a  very  few  years  any  mercurial  thermometer  on  which  the 
divisions  were  etched  within  a  year  of  the  bulb  being  blown  and  filled,  was 
sure  to  become  from  a  quarter  to  half  a  degree  too  high  within  the  following 
six  months,  wherefore  the  best  makers  kept  large  stocks  of  filled,  but  un- 
graduated  tubes,  and  rarely  put  the  divisions  on  until  they  were  two  or  three 
years  old.  Some  years  since  Mr.  Denton,  a  skilled  thermometer  maker, 
discovered  that,  by  a  process  of  slow  annealing  in  hot  oil,  this  change  could 
be  effected  in  weeks  instead  of  years,  and  now,  if  the  matter  be  insisted  upon, 
and  a  reasonable  price  paid,  thermometers  can  be  bought  which  have  what 
is  called  a  constant  zero — i.e.  which  will  not  read  higher  by  age.  Now  it 
will  be  seen  why  thermometers  should  not  be  made  hurriedly,  and  that  if  a 
purchaser  insists  upon  one  being  made  and  delivered  within  a  week,  the 
maker  will  probably  so  divide  it  that  it  shall  read  0-2°  or  0*3°  too  low  when 
supplied,  because  he  knows  that  eventually  it  will  rise  not  only  so  as  to  become 
correct,  but  possibly  0*2°  or  0"3°  too  high. 

The  only  ordinary  thermometer  required  for  climatological  purposes  is 
the  one  mounted  along  with  another  to  form  an  hygrometer.  I  shall,  there- 
fore defer  its  description  until  I  write  upon  hygrometry. 

Kegisteeing  Thbemometees 

There  are  two  terms  often  confused  and  misused  by  amateurs — self-regis- 
tering and  self-recording  ;  the  word  '  self '  being  in  both  cases  redundant  and 
misleading.  The  proper  application  is  registering  to  anything  which  moves 
an  index  which  can  be  subsequently  examined  :  a  gas  meter  is  a  self- 
registering  apparatus  ;  on  the  contrary,  any  instrument  which  by  pen,  pencil. 


ICO 


HYGIENE 


photography,  or  otherwise  makes  a  continuous  trace  upon  paper,  &c.,  pro- 
duces a  record  and  is  recording. 

It  would  be  quite  out  of  place  to  describe  any  patterns  of  registering 
thermometer,  except  those  in  general  use  ;  this  will  exclude  probably  a 
hundred  patterns,  and  leave  scarcely  half  a  dozen — the  survival  of  the  fittest. 
The  oldest,  invented  about  1780  by  James  Six  of  Canterbury  (not  Col- 
chester, as  is  often  stated),  is  not  now  used  for  climatological  purposes,  but 
is  very  popular  as  a  window  thermometer,  and  is  convenient  as  a  check  on 
the  warming  of  public  buildings,  hospital  wards,  &c.  ;  it  is  also  much  used 
for  taking  the  temperature  of  the  sea,  and  can  do  so  even  under  several 
miles  of  water,  and  when  the  pressure  is  two  or  more  tons  to  the  square  inch. 
Fig.  60  represents  the  instrument  as  fitted  for  a  window.  The  bulb  of  the 
thermometer  is  the  long  cyhnder  in  the  middle,  which,  as  well  as  the  upper 
part  of  the  '  cold  '  tube,  is  filled  with  alcohol ;  below  this  the  tube  is  filled 
with  mercury,  Avhich  passes  round  the  bend  at  the  bottom  and  part  way  up 
the  '  heat '  tube.  Above  this  the  space  in  that  tube  is  also 
filled  with  alcohol,  except  that  in  the  upper  part  of  the  chamber 
at  the  top  there  is  confined  some  air  which  was  sealed  in  at 
so  low  a  temperature  that  at  any  ordinary  temperature  it  exerts 
a  pressure  upon  the  alcohol  in  the  '  heat '  tube,  and  then, 
through  the  mercury,  upon  the  alcohol  in  the  '  cold  '  tube. 
The  effect,  or  supposed  effect,  of  this  is  to  keep  the  two  liquids 
in  their  place,  and  to  prevent  air  bubbles  escaping  from  the 
alcohol  and  deranging  the  instrument.  These  are  its  drawbacks, 
and  they  make  it  a  very  bad  traveller.  A  Six's  thermometer, 
if  well  made  and  once  safely  in  position,  is  the  handiest  self- 
registering  thermometer  in  use,  but  it  should  be  moved  as  little 
as  possible  and  always  carried  vertically.  The  difficulty  arising 
from  motion  will  soon  become  evident.  The  indexes  consist 
of  three  parts  (and  are  not  always  made  of  the  same  shape 
or  materials) :  (a)  the  steel  needle ;  this  is  essential  but  it 
is  sometimes  bare,  sometimes  enclosed  in  a  little  glass  tube  ; 
(&)  knobs  of  glass  at  each  end  of  the  index,  the  lower  one  to 
be  driven  up  by  the  mercury  ;  (c)  springs  to  hold  the  index 
in  position  and  prevent  its  falling;  these  are  sometimes 
bristles,  sometimes  bent  threads  of  glass.  The  action  of  the 
thermometer  is  simple  and  very  ingenious.  Suppose  that  the 
instrument  has  just  been  read  ;  to  set  it  ready  for  the  next 
observation  take  a  horse- shoe  magnet  and  place  it  successively 
at  the  side  of  each  needle  and  draw  the  indexes  gently  down 
until  they  rest  upon  the  mercury  ;  the  lower  knob  of  each 
will  then  read  alike  and  will  show  the  temperature  at  that 
instant.  Having  done  so,  suppose  that  the  temperature  rises,  the  alcohol  in 
the  bulb  will  expand,  it  will  pass  the  index  in  the  '  cold '  leg,  and  push  down 
the  mercury,  but  that  will  compel  the  mercury  to  rise  in  the  '  heat '  leg,  and 
to  drive  up  the  index  in  it  until  the  temperature  ceases  to  rise,  when  the 
index  will  be  left  behind  and  the  maximum  temperature  will  be  registered 
by  the  position  of  the  bottom  of  that  index.  Just  the  reverse  will  happen 
on  a  fall  of  temperature,  for  then  the  spirit  in  the  bulb  will  contract,  the 
pressure  in  the  chamber  at  the  top  of  the  '  heat '  leg  will  force  the  mercury 
down  in  it  and  up  in  the  '  cold  '  one,  and  it  will  push  that  index  upwards  as 
long  as  the  temperature  continues  to  fall.  It  is  obvious  from  the  above  that 
the  temperature  scales  must  read  downwards  in  the  '  cold '  and  upwards  in 
the  '  heat '  leg,  and  that  in  each  leg  the  bottom  of  the  index  shows  respec- 


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METEOROLOGY 


161 


iively  the  lowest  and  the  highest  temperature  reached  since  the  instrument 
was  last  set.  It  is  evident  that  a  thermometer  of  this  kind  placed  inside  a 
fixed,  locked,  wire  cage  gives  evidence  of  the  variations  in  temperature 
between  two  consecutive  visits  of  the  superior  officer. 

Before  leaving  this  pattern  it  is  necessary  to  mention  one  peculiar  error 
to  which  this  thermometer  is  liable.  Sometimes  alcohol  will  ooze  round  by 
the  side  of  the  mercury,  and  so  pass  from  the  '  cold  '  to  the  '  heat '  leg.  This 
is  doubly  bad  {a)  because,  inasmuch  as  the  scales  run  in  opposite  directions, 
it  can  only  be  detected  by  comparison  with  another  thermometer,  and  {h) 
because  no  one  but  an  optician  can  rectify  the  evil. 


EUTHEEFOED'S   MINIMUM 

All  the  world  over  this  very  simple  pattern  of  thermometer  holds  the 
iirst  place  as  a  minimum  thermometer ;  not  that  it  is  perfect — it  has  several 
faults,  but  because  no  other  has  been  able  to  displace  it.  It  was  invented 
nearly  a  century  since  and  described  in  1794  in  the  '  Ed.  Phil.  Trans.' 
Its  action,  as  will  be  seen  from  fig.  61,  is  very  simple.  The  bulb  and  part  of 
the  stem  are  filled  with  alcohol  in  which  a  glass  index  is  placed  :  when 
ihe  temperature  falls,  the  cohesion  of  the  end  of  the  alcohol  is  sufficient 
to  draw  the  index  back  with  it  towards  the  bulb  ;  but  when  the  tem- 
perature rises  again,  the  alcohol  passes  the  index  and  leaves  the  extremity 
-furthest  from  the  bulb  at  the  lowest  temperature  reached.     The  end  of  the 


Fig.  61. 


column  furthest  from  the  bulb  should  always  agree  within  about  half  a 
degree  with  that  of  an  accurate  mercurial  thermometer  hung  by  its  side. 
I  make  this  reservation  as  to  0°-5  because  spirit  thermometers,  being  slug- 
gish, differ  from  mercurial  ones  when  rapid  changes  are  in  progress.  This 
thermometer  does  not  require  a  magnet  to  set  it ;  its  usual  position  is  nearly 
horizontal ;  if  anything,  the  bulb  end  slightly  lower  than  the  other.  To  set 
it,  unhang  it  and  raise  the  bulb,  the  index  will  then  of  its  own  weight  slide 
down  to  the  end  of  the  column.  Two  faults  occur  with  this  thermometer  : 
sometimes,  but  rarely,  bubbles  of  air  appear  in  the  column  and  fix  the  index ; 
more  frequently  error  arises  from  the  distillation  of  some  of  the  alcohol,  and 
its  condensation  at  the  top  of  the  tube.  This  is  generally  visible  without 
difficulty,  but  is  not  obvious,  because  if  the  alcohol  in  the  stem  be,  as  is 
usual,  coloured,  that  which  condenses  at  the  top  is  frequently  quite  colour- 
less. At  one  time  opticians  freqviently  buried  this  portion  of  the  tube  under 
the  mounting,  but  that  practice  has  fortunately  been  abandoned.  Both  these 
faults  are  usually  easily  cured  by  the  observers  themselves,  and  both  by  the 
same  process.  Hold  the  thermometer  firmly  near  the  bulb,  and  bulb  down- 
wards ;  then  swing  it  rapidly  with  the  right  hand,  taking  care,  of  course,  to 
hit  nothing ;  the  centrifugal  force  will  usually  cause  a  broken  column  to 
unite,  and  will  throw  any  alcohol  from  the  top  of  the  tube.  After  so  swing- 
ing the  thermometer,  it  should  be  stood  bulb  downwards  for  an  hour  so  as  to 
drain,  and  it  will  be  well  afterwards  to  compare  it  with  a  mercurial  one  to 
see  that  all  is  correct.     The  index  will  very  probably  be  thrown  into  the 

VOL.    I.  M 


162  HYGIENE 

bulb  by  this  swinging,  but  a  very  little  gentle  coaxing  will  bring  it  out  again.. 
Sometimes,  if  the  tube  be  very  fine  and  the  amount  of  condensed  spirit  very 
small,  it  has  not  momentum  enough  to  move  from  the  top  ;  it  can  then  be 
displaced  only  by  evaporation,  and  a  match  or  a  small  spirit  lamp  should  be 
applied  to  the  tube  where  the  condensed  spirit  is  lodged.  Of  course  care 
must  be  taken  not  to  apply  heat  so  suddenly  as  to  crack  the  tube. 


PHILLIPS'S   MAXIMUM   THERMOMETER 

This  thermometer,  invented  by  Professor  J.  Phillips,  F.R.S.,  as  early  as 
1832,  and  described  by  him  in  the  '  Eeport  of  the  British  Association '  for 
that  year,  was  remarkably  slow  in  becoming  known.  How  it  was,  and  why 
it  was,  that  twenty  years  after  its  invention  the  Royal  Observatory  was  still 
employing  the  very  bad  maximum  invented  by  Rutherford,  is  one  of  the 
facts  which  it  is  difficult  to  explain.  It  was  probably  partly  Professor 
Phillips's  w^ell-known  modesty,  and  partly  that  no  optician  had  a  pecuniary 
interest  in  pushing  it.  Possibly  the  very  slight  use  made  of  the  invention 
in  this  country  led  to  its  being  unknown  to,  or  ignored  by,  M.  Walferdin,. 
who  described  an  identical  arrangement  to  the  Academic  des  Sciences, 
April  24,  1854,  as  his  own.  To  the  same  cause  must  probably  be  attributed 
the  following  curiously  incorrect  statement  by  M.  Eenou :  ^ — '  Depuis 
quelques  annees  les  Anglais  ont  adopte  ce  thermometre  qu'ils  appellent 


Fig.  62. 

thermometre  h  maximum  de  Phillips,  mais  h  tort,  I'invention  appartient 
bien  positivement  a  M.  Walferdin.'  Reference  to  the  '  British  Association 
Report '  settles  the  question  of  priority  by  twenty-two  years  in  favour  of 
Phillips,  though  very  likely  the  invention  by  M.  Walferdin  was  genuine. 
On  the  Continent  this  pattern  is  generally  described  not  by  either  name  but 
as  'thermometre  a  bulle  d'air.'  Its  construction  is  shown  by  fig.  62  ;  it  is 
very  simple  and  easily  understood.  In  the  manufacture  a  very  small  bubble 
of  air  is  introduced  into  the  tube,  separatmg  10°  or  15°  at  the  extremity 
from  the  remainder  of  the  column.  In  the  pattern  represented  by  fig.  62, 
and  which  is  that  used  for  meteorological  purposes,  this  detached  portion 
■will  be  seen  to  be  many  degrees  away  from  the  top  of  the  column,  but  that 
is  merely  for  the  convenience  of  illustrating  the  principle.  Assume  that  the 
thermometer  is  found  as  per  fig.  62,  it  then  shows  that  since  the  instrument 
was  last  set,  the  temperature  had  at  some  time  reached  70°'8.  To  set  the 
thermometer  it  should  be  taken  off  the  hooks  and  the  bulb  end  lowered 
until  the  detached  portion  runs  back  and  nearly  joins  the  top  of  the  column 
(with  some  thermometers  even  a  slight  shake  may  be  necessary),  then  re- 
hang  it  nearly  horizontal,  bulb  end  slightly  lowest ;  it  will  then  show  the 
existing  temperature,  and  when  any  increase  occurs  the  detached  portion 
will  be  pushed  along,  its  extremity  furthest  from  the  bulb  marking  the 
highest  temperature  reached  ;  if  the  temperature  fall,  this  detached  portion 
is  left  behind  and  thus  registers  the  maximum. 

'  Armimire  Soe.  Met.  dc  France,  t.  xxiv.  p.  61. 


METEOBOLOGY 


16S 


If  the  index-column  be  short,  this  form  of  thermometer  can  be  used  in 
any  position,  vertical  or  horizontal,  bulb  up  or  bulb  down,  and  I  have 
myself  used  it  in  a  well  1,000  feet  deep,  where  it  had  to  bear  the  jolts  of 
raising  and  lowering  by  a  windlass  ;  the  only  difference  is,  that  with  such  a 
short  index  a  sharp  swing  is  necessary  to  reset  it. 

As  thermometers  on  this  principle  can  be  made  with  extremely  fine 
bores  it  has  been  very  largely  adopted  for  clinical  thermometers  ;  in  fact,  it 
was  used  in  the  very  first  made  for  Dr.  Aitken  by  Mr.  Casella,  and  since 
that  time  probably  100,000  have  been  made  upon  that  model. 


NEGKETTI  AND  ZAMBEA'S  MAXIMUM 

While  Phillips's  maximum  was  lying  dormant,  if  not  forgotten,  the 
Great  Exhibition  of  1851  was  opened,  and  the  jury  who  had  to  deal  with 
meteorological  instruments,  having  nothing  before  them  except  specimens  of 
Six's  and  of  Rutherford's  thermometers,  and,  strangely  enough,  apparently 
not  knowing  of  Phillips's  maximum,  pointed  out  that  a  trustworthy  maximum 
was  much  wanted.  Messrs.  Negretti  and  Zambra  were  determined  to  meet 
this  want,  and  in  little  more  than  a  year  brought  out  their  excellent  patent 
maximum  which  is  shown  in  fig.  63.  Like  Phillips's,  it  is  (for  meteorological 
purposes)  used  in  a  nearly  horizontal  position — the  bulb  slightly  lower  than 
the  top.     Its  construction  is  as  follows  : — First  an  ordinary  thermometer 


Fig.  63. 

tube  (rather  large)  is  prepared  ;  then  a  thread  of  glass  about  one-fourth  of 
an  inch  long  is  dropped  down  to  near  the  bulb  end,  and  the  stem  at  that 
point  and  the  contained  fibre  are  heated  to  softness  and  slightly  bent.  This 
fixes  the  fibre  and  forms  an  obstruction  in  the  tube,  which  tube  is  sub- 
sequently filled  with  mercury  as  an  ordinary  thermometer.  When  in  use,  if 
the  temperature  rises,  the  mercury  in  the  bulb  expands  and  forces  its  way 
past  the  obstruction  ;  but  if  the  temperature  falls,  the  molecular  attraction  of 
the  mercury  is  insufficient  to  induce  the  column  to  pass  the  obstruction,  and 
therefore  the  full  length  remains  in  the  tube,  and  the 
extremity  shows  the  highest  temperature  reached.  The 
thermometer  is  reset  by  lowering  the  bulb  end  and,  if 
necessary,  giving  the  thermometer  a  swing,  bulb  down- 
wards. 

IMMISCH'S   THEEMOMETEES 

These  are  extremely  small,  accurate,  and  handy 
thermometers  which,  as  fig.  64  shows,  are  quite  unlike 
an  ordinary  thermometer.  They  owe  their  indication 
to  the  expansion  of  a  liquid  in  a  small  tube,  bent 
nearly  to  a  circle,  which  tends  to  straighten  with  in-  „ 

crease  of  heat ;  this  motion  is,  by  very  fine  mechanism, 

made  to  cause  the  hand  to  travel  over  the  dial.     It  is  quite  usual  for  these 
little  thermometers  to  be  true  to  less  than  0°*1  F.     Some  are  graduated  for 

u2 


164 


HYGIENE 


ordinary  use,  some  for  the  limited  range  required  for  clinical  purposes.  ]\rr. 
Immisch  has  recently  added  an  arrangement  which  makes  them  virtually 
registering. 

RICHARD'S   RECORDING   THERMORIETER 

Until  lately  the  cost  of  recording  thermometers  was  so  great  {101.  or  801.) 
as  to  prevent  their  adoption  at  any  but  richly  endowed  observatories ;  but 
within  the  last  few  years  MM.  Eichard  Freres  of  Paris  have  perfected  the 
pattern  shown  in  fig.  65,  and  sell  them  at  so  low  a  price  as  to  render  the 
instrument  generally  accessible  ;  it  therefore  claims  a  few  words  here.  The 
bulb,  like  Immisch's,  is  a  curved,  flattened  tube  filled  with  a  hquid,  but  as  it 
has  more  work  to  do  it  is  enormously  larger.  The  changes  in  the  curvature 
of  the  tube  cause  the  long  lever  to  rise  with  increase  of  temperature  and  to 
fall  with  decrease.  This  marks  on  a  cylinder  on  exactly  the  same  system 
as  the  barograph  already  described.     When  duly  wound  up  and  started  it 


I 


Fig, 


can  be  locked  up  and  left  untouched  until  the  corresponding  hour  in  the 
following  week,  when  a  record,  true,  probably,  to  0°-5  F.,  will  be  found  for 
every  instant  during  the  week.  As  the  curvature  of  the  tube  or  the  strength 
of  the  spring  \nl\  sometimes  alter,  the  reading  of  an  accurate  mercurial 
thermjDmeter  should  be  noted  when  a  new  sheet  is  put  on,  so  that,  if  neces- 
sary, the  position  of  the  lever  may  be  adjusted  to  correspond  with  it. 


HYGROMETRY 

This  branch  of  meteorology  is  not  in  a  satisfactory  state.  Quite  two 
hundred  forms  of  hygrometer  have  been  devised,  but,  except  in  rare  cases 
and  for  experimental  purposes,  only  two  survive,  viz.  the  dry  and  wet  bulb 
(sometimes  erroneously  called  Mason's)  hygrometer,  and  Saussure's  hair  hygro- 
meter. The  dry  and  wet  bulb  is  almost  the  only  form  used  in  the  British 
Isles  and  in  our  Colonies,  and  it  is  the  more  usual  on  the  Continent,  but  as 
frosts  are  more  intense  at  Continental  stations  than  at  British  ones,  and  the 


METEOBOLOQY 


165 


wet  bulb  thermometer  requires  great  care  and  attention  in  time  of  frost,  it  is 
usual  on  the  Continent  to  have  also  a  Saussure  hair  hygrometer  and  to  fall 
back  upon  it  in  frosty  weather. 


Dry  and  Wet  Bulb 

The  general  form  of  the  dry  and  wet  bulb  hygrometer  is  shown  in  fig.  66. 
It  is  an  easy  instrument  to  read,  and,  provided  that  it  be  supplied  with  rain 
or  distilled  water  and  with  clean  muslin  and  wick,  requires  no  attention 
except  in  frosty  weather ;  then  it  has  to  be  visited  about  half  an  hour  before 
the  regular  time  of  observation,  and  the  muslin  brushed  over  with  a  camel- 
hair  brush  dipped  in  cold  water ;  this  will  freeze  before  the  time  of  the 
regular  observation,  and  the  reading  of  the  ice-covered  bulb  will  give  as 
correct  an  indication  of  the  numidity  of  the  air  as  does  the  bulb  when  wet. 

Perhaps  some  very  elementary  remarks  upon  the  use  of  this  instrument 
may  be  excused,  for,  common  as  it  is,  there 
are  many  who  do  not  know  the  principle 
upon  which  it  is  based,  nor,.  e.g.,  what  is 
the  temperature  of  evaporation,  or  what 
its  relation  to  the  temperature  of  the  dew 
point.  It  would  be  out  of  place  to  give 
here  a  treatise  on  hygrometry ;  we  give 
only  some  fragments. 

The  dry  and  wet  bulb  thermometer  in- 
dicate the  amount  of  moisture  present  in 
the  air  by  the  difference  between  the  read- 
ing of  the  two  thermometers  :  the  dry  bulb 
gives  the  temperature  of  the  air,  the  wet 
bulb  gives  a  temperature  lower  than  that  of 
the  air,  in  proportion  to  the  rapidity  with 
which  the  water  is  removed  from  the  wet 
bulb  by  evaporation.  To  take  a  homely 
illustration,  when  one's  head  is  too  hot, 
one  applies  eau  de  Cologne,  because  the 
rapid  evaporation  of  the  spirit  will  quickly 
cool  the  skin ;  so  does  the  water  cool  the 
wet  bulb  thermometer.  Moreover,  the  drier 
the  air,  the  faster  does  the  evaporation  pro- 
ceed, and,  therefore,  the  greater  the  cooling ; 

hence,  roughly,  the  greater  the  depression  of  the  wet  bulb  below  the  dry,  the 
drier  the  air — we  have  said  roughly,  because  the  value  of  a  depression  of 
(say)  6°  is  much  greater  at  low  than  at  high  temperatures. 

For  anything  like  intelligent  use  of  a  dry  and  wet  bulb  thermometer  a 
set  of  tables  is  indispensable  ;  those  generally  used  in  this  country  were  com- 
piled many  years  since  by  Mr.  J.  Glaisher,  F.E.S.,  but  analogous  ones  have 
since  been  prepared  in  many  countries. 

It  remains  for  us  to  point  out  the  meaning  of  the  term  '  dew-point 
temperature  :  '  it  is  that  temperature  at  which  the  air  will  deposit  the  moisture 
contained  in  it.  This  can  be  ascertained  directly  by  Dines's  hygrometer  (see 
p.  166)  or  by  calculation  from  the  reading  of  the  dry  and  wet  bulb  thermo- 
meter. Very  roughly  it  may  be  said  to  be  about  as  much  below  the  wet 
bulb  reading  as  the  wet  bulb  itself  is  below  the  dry. 

In  a  perfectly  saturated  atmosphere  the  two  thermometers  should  read 
alike.     Sometimes  the  wet  bulb  wiU  read  a  few  tenths  higher  than  the  dry 


166 


HYGIENE 


bulb  ;  this  not  infrequently  leads  hasty  persons  to  the  conclusion  that  one  of 
the  thermometers  must  be  wong.  This  does  not  follow :  first,  because 
when  the  air  is  saturated  the  dry  bulb  is  almost  always  coated  with  a  thin 
film  of  water,  is,  in  fact,  a  better  wet  bulb  than  the  one  covered  with  mushn  ; 
and,  secondly,  because  the  proper  wet  bulb  is  by  its  covering  of  muslin  pro- 
tected from  radiation,  and  so  kept  slightly  warmer  than  the  air. 

The  depression  of  the  wet  bulb  below  the  dry 
bulb,  which,  as  just  explained,  in  a  wet  fog  is 
nil,  may,  in  rare  cases,  even  in  England,  exceed 
20° ;  but  the  average  difference  ranges  from  1°  or 
2°  in  winter  to  G^  or  8°  in  summer. 

Saussuee's  Hygkometeb 

One  form  of  Saussure's  hygrometer  is  shown  in 
^  fig.  67.     It  is  not  an  independent  instrument,  but 

^^_      has  to   be   set  to  correspond  with   the   value  as 
1^  computed  from  a  dry  and  wet  bulb  thermometer. 

It  depends  upon  the  fact  that  a  human  hair  elon- 
gates by  moisture  and  contracts  by  dryness.  A 
hair  (a)  is  therefore  (after  proper  treatment  as  to 
grease,  &c.)  fastened  at  one  end  (&),  while  the  other 
has  a  slight  weight  id)  attached  to  keep  it 
stretched,  and  is  fastened  to  a  lever  so  that  its 
movements  may  be  magnified  and  easily  read  upon 
the  scale.  The  total  motive  power  of  the  hair 
Fic  g7  being  very  small,  the  friction  of  the  axle  becomes  a 

serious  element,  and  I  have  seen  a  form  of  the 
instrument  in  which  there  was  no  friction.  The  hair  was  fixed  at  its  upper 
extremity,  the  tension  was  provided  by  a  small  weight  tied  to  the  bottom  of 
the  hair,  which  hung  in  the  centre  of  a  pierced  tube,  the  lower  part  of  which 
was  of  ground  glass  with  divisions  etched  upon  it ;  the  reading  was  by  a 
microscope  so  arranged  that  it  and  the  bottom  of  the  weight  could  be  brought 

exactly  opposite  the  scale  and  the 
length  then  read  off. 

DiNEs's  Hygrometer 

This  is  the  simplest  form  of 
condensation  hygrometer,  of  which 
the  earlier  types  were  the  hygro- 
meters of  Daniell,  Eegnault,  Al- 
luard,  and  others.  Dines's  is  dis- 
tinguished from  all  the  others  in 
that  it  only  requires  ether  when 
the  dew  point  is  at  or  below  32°  ; 
at  all  higher  temperatures  cold 
water  is  alone  required.  One  form 
of  it,  which  well  illustrates  its 
prmciple,  is  shown  in  perspective  and  section  in  fig.  68.  The  vessel  A  is 
filled  with  cold  water  (ice  being  added  if  required),  which  passes  over  the 
thermometer  bulb,  and  at  the  same  time  against  the  under  surface  of  the 
very  thin  sheet  of  glass  at  E.  The  observer  watches  for  the  deposition  of 
dew  on  the  glass,  and  the  thermometer  at  that  instant  gives,  without  any 
calculation,  the  dew-point  temperature. 


Fig.  '68. 


METEOROLOGY 


107 


RAINFALL 

This  subject  has  on  account  of  its  great  engineering  importance  received 
much  attention,  and  there  are  now  few  countries  in  the  world  without  special 
organisations  for  its  registration.  As  the 
natural  result  thereof,  considerable  ap- 
proach has  been  made  towards  uniformity 
in  the  pattern  of  rain  gauge  and  in  the 
mode  of  registration.  It  used  (fifty  years 
since)  to  be  not  unusual  to  put  rain 
gauges  on  roofs  (I  suppose  that  they 
might  be  the  nearer  to  where  the  rain 
came  from),  but  long  before  that  it  had 
been  shown  (but  forgotten)  that  gauges 
on  elevated  buildings  collect  much  less 
than  those  near  the  ground.^  In  the 
British  Isles,  in  India,  Ceylon,  Canada, 
and  in  nearly  all  our  Colonies,  the  gauges 
are  one  foot  above  ground.  On  the  con- 
tinent of  Europe,  in  Algeria,  Java,  and 
Sumatra,  they  are  generally  from  three 
to  five  feet  above  the  ground,  and  there- 
fore record  about  three  per  cent,  less 
than  they  would  do  if  at  one  foot.  In 
the  United  States,  owing  to  the  Signal 
Office  stations  being  mostly  in  the  heart  of  cities,  a  great  many  of  the  rain 
gauges  are  understood  to  be  on  house  tops.  No  satisfactory  discussion  of 
American  rainfall  can  be  based  on  such  observations. 

The  pattern  of  gauge  generally  used  in  this  country  is  shown  in  fig.  69  ; 
this  represents  one  five  inches  in  diameter,  but  there  are  also  many  eight- 
inch  ones  at  work,  and  those  established  in  France  by  the  Association 
JFrancaise  of  about  eight  and  a  half  inches  diameter  are  very  similar  in  pattern. 
The  vertical  portion  of  the  funnel,  i.e.  that  above  the  cone,  is  known  as  a 
Snowdon  rim  (from  having  in  England  been  adopted  first  for  gauges  intended 
for  use  near  Snowdon),  and  is  intended  to  secure  the  accurate  ineasurement 
of  slight  falls  of  snow.  Having  entered  the  funnel,  the  rain  passes  down 
through  a  tube,  made  long  and  narrow  to  check  evaporation,  into  the  bottle, 
where  it  remains  until  measurement.  If  the  fall  be  exceptionally  great,  or 
if  a  sudden  frost  sets  in,  freezes  the  water,  and  cracks  the  bottle,  the  record 
is  not  spoiled,  for  the  water  is  saved  by  the  can,  and  may  be  measured  almost 
as  well  as  if  nothing  had  happened.  The  measuring  jar  is  di^dded  propor- 
tionally to  the  area  of  the  gauge,  the  diameter  of  which  should  always  be  an 
exact  dimension,  5*00  inches  or  8*00  inches,  as  it  is  then  easy,  if  the  original 
measuring  jar  is  broken,  to  obtain  a  new  one  precisely  adapted  to  the  fimnel. 
The  principle  of  graduation  is  so  obvious  as  scarcely  to  need  mention.  Take 
a  5-inch  gauge  ;  if  the  diameter  be  5  inches  the  area  is  19'64  inches,  therefore 
a  rainfall  of  an  inch,  i.e.  1  inch  deep  over  the  whole  of  a  parish  or  town, 
would  in  this  rain  gauge  deposit  19"64  cubic  inches,  or  4958  grains  of  water. 
It  is  found  in  practice  most  convenient  to  make  the  jar  hold  half  an  inch. 
Therefore  2479  grains  are  poured  in  and  the  jar  is  marked  wath  a  hne  repre- 
senting 0'50  inch  or  \  inch  ;  subdivisions  are  similarly  marked,  and  so  finally 

'  This  deficiency  has  been  proved  to  be  due  to  the  wind  blowing  the  rain  over,  and  out 

of,  the  funnels  of  gauges  in  exposed  positions. 


168  HYGIENE 

the  jar  lias  fifty  di\dsions,  one  for  eacb  i-J-ytli  of  an  inch,  and  is  figured  at 
•10,  '20,  -30,  •10,  and  "50.  As  regards  the  general  manner  of  observing  and 
recording  rainfall,  it  seems  best  to  reprint  in  extenso  the  rules  drawn  up  for 
the  use  of  British  observers. 

Suggestions  for  Securing  Uniformity  of  Practice  among  Eaixfall  Observers 

1.  Site. — A  rain  gauge  should  not  be  set  on  a  roof,  a  slope,  or  a  terrace,  but  on  a  level 
piece  of  ground,  at  a  distance  from  shrubs,  trees,  walls,  and  buildings— at  the  very  least 
as  many  feet  from  tlieir  base  as  they  are  in  height.  Tall-growing  flowers,  vegetables,  and 
bushes  must  be  kept  away  from  the  gauge.  If  a  thoroughly  clear  site  cannot  be  obtained,, 
shelter  is  most  endurable  from  NW.,  N.,  and  E.,  less  so  from  S.,  S.E.,  andW.,  and  not  at 
all  from  S.W.  orUE. 

2.  Old  Gauges. — Old-established  gauges  should  not  be  moved,  nor  their  registration 
discontinued  until,  at  least,  two  years  after  a  new  one  has  been  in  operation,  otherwise 
the  continuity  of  the  register  will  be  irreparably  destroyed.  Both  the  old  and  the  new 
ones  must  be  registered  at  the  same  time,  and  the  results  recorded  for  comparison. 

3.  Level  and  Fixing. — The  funnel  of  a  rain  gauge  must  be  set  quite  level,  and  so 
firmly  fixed  that  it  will  remain  so  in  spite  of  any  gale  of  wind  or  ordinary  circumstance.. 
Its  correctness  in  this  respect  should  be  tested  from  time  to  time. 

4.  Height. — The  funnels  of  gauges  newly  placed  should  be  1  ft.  above  grass.  Information, 
respecting  height  above  sea-level  may  be  obtained  from  the  Editor  of  '  British  Eainfall.' 

5.  Rnst. — If  the  funnel  of  a  japanned  gauge  becomes  so  oxidised  as  to  retain  the  rain 
in  its  pores,  or  threatens  to  become  rusty,  it  should  have  a  coat  of  gas  tar,  or  japan  black, 
or  a  fresh  funnel  of  zinc  or  copper  should  be  provided. 

(3.  Float  Gauges. — If  the  measuring  rod  is  detached  from  the  float,  it  should  never  be 
left  in  the  gauge.  If  it  is  attached  to  the  float,  it  should  be  pegged  or  tied  down,  and  only 
allowed  to  rise  to  its  proper  position  at  the  time  of  reading.  To  allow  for  the  weight  of 
the  float  and  rod,  these  gauges  are  generally  so  constructed  as  to  show  0  only  when  a 
small  amount  of  water  is  left  in  them.  Care  must  always  be  taken  to  set  the  rod  to  the 
zero  or  0. 

7.  Can  and  Bottle  Gauges. — The  measuring  glass  should  always  be  held  upright,  or 
l^laced  on  a  level  slab  ;  the  reading  is  to  be  taken  midway  between  the  two  apparent 
surfaces  of  the  water. 

8.  Tivie  of  Reading. — 9  a.m.  daily ;  if  taken  only  monthly,  then  9  a.m.  on  the  1st. 

9.  Date  of  Entry. — The  amount  measured  at  9  a.m.  on  any  day  is  to  be  set  against  the 
previous  one ;  because  the  amount  registered  at  9  a.m.  of,  say,  the  17th  contains  the  fall 
during  15  hours  of  the  16th,  and  only  9  hours  of  the  17tli. 

10.  Mode  of  Entry. — If  less  than  one-tenth  (-10)  has  fallen,  the  cypher  must  aliuays 
be  prefixed ;  thus,  if  the  measure  is  full  up  to  the  seventh  line,  it  must  be  entered  as  •07,. 
that  is,  no  inches,  no  tenths,  and  seven  hundredths.  There  must  always  be  two  figures 
to  the  right  of  the  decimal  point.  Even  in  the  case  of  one-tenth  of  an  inch  (usually 
written  -1)  a  cypher  must  be  added,  making  it  •lO.  Neglect  of  this  rule  causes  much 
inconvenience.  All  columns  should  be  cast  tivice — once  up  and  once  down,  so  as  to  avoid 
the  same  error  being  made  twice.  Never  copy  a  total,  always  cast  the  column  afresh. 
When  there  is  no  rain,  a  line  should  be  drawn  rather  than  cyphers  inserted. 

11.  Caution. — The  amount  should  always  be  written  down  before  the  water  is  thrown 
away. 

12.  Small  Quantities. — The  unit  of  measurement  being  -01,  observers  whose  gauges 
are  sufiiciently  delicate  to  show  less  than  that,  are,  if  the  amount  is  under  -005,  to  throw 
it  away  ;   if  it  is  '005  to  -010  inclusive,  they  are  to  enter  it  as  •01. 

13.  Absence. — Every  observer  should  train  some  one  as  an  assistant ;  but  where  thiS' 
is  not  possible,  instructions  should  be  given  that  the  gauge  be  emptied  at  9  a.m.  on  the 
1st  of  the  month,  and  the  water  bottled,  labelled,  and  tightly  corked,  to  await  the  observer's 
return. 

14.  Heavy  Rains. — When  very  heavy  rains  occur,  it  is  desirable  to  measure  imme- 
diately on  their  termination,  and  it  will  be  found  a  safe  plan  after  measuring  to  return  the 
water  to  the  gauge,  so  that  the  morning  registration  will  not  be  interfered  with.  Of  course 
if  there  is  the  slightest  doubt  as  to  the  gauge  holding  all  that  falls,  it  must  be  emptied,, 
the  amount  being  previously  wi-itten  down  and  added  to  the  subsequent  measurement. 

15.  Snow. — In  snow  three  methods  may  be  adopted — it  is  well  to  try  them  all. 
(1)  Melt  what  is  caught  in  the  funnel  by  adding  to  the  snow  a  previously  ascertained 
quantity  of  warm  water,  and  then,  deducting  this  quantity  from  the  total  measurement, 
enter  the  residue  as  rain.     (2)  Select  a  place  where  the  snow  has  not  drifted,  invert  the- 


METEOBOLOGY  IGO 

funnel,  and,  turning  it  round,  lift  and  melt  what  is  enclosed.  (3)  Measure  with  a  rule  the 
average  depth  of  snow,  and  take  one-twelfth  as  the  e(iuivalent  of  water.  This  being  a 
very  rough  method,  is  not  to  be  adopted  if  it  can  be  avoided.  Some  observers  use  in 
snowy  weather  a  cylinder  of  the  same  diameter  as  the  rain  gauge,  and  of  considerable 
depth.  If  the  wind  is  rough,  all  the  snow  is  blown  out  of  a  flat-funnelled  rain  gauge. 
Snowdon  pattern  gauges  are  much  the  best. 

16.  Overflow. — Not  a  year  passes  in  which  some  gauges  are  not  allowed  to  overflow ;  it 
is  therefore  necessary  to  call  attention  to  the  fact  that  there  does  not  seem  to  be  any  part 
of  the  British  Isles  where  4  inches  may  not  fall  in  24  hours.  It  is  not  desirable  to  purchase 
any  gauge  of  which  the  capacity  is  less  than  6  inches. 

17.  Second  Gauges. — It  is  desirable  that  observers  should  have  two  gauges,  and  that 
one  of  them  should  be  capable  of  holding  8  inches  of  rain.  One  of  the  gauges  should  be 
registered  daily,  the  other  weekly  or  monthly  as  preferred,  but  always  on  the  1st  of  each 
month.  By  this  means  a  thorough  check  is  kept  on  accidental  errors  in  the  entries,  which 
is  not  the  case  if  both  are  read  daily.  Observers  having  two  gauges  and  recording  both 
daily,  should  keep  the  records  distinct,  and  forward  a  copy  of  each.  Never  take  a  mean 
of  two. 

18.  Deiu  and  Fog. — Small  amounts  of  water  are  at  times  deposited  in  rain  gauges  by 
fog  and  dew ;  they  should  be  added  to  the  amount  of  rainfall,  because  (1)  they  '  tend  to 
water  the  earth  and  nourish  the  streams  ; '  and  not  for  that  reason  only,  but  (2)  because 
in  many  cases  the  rain  gauges  can  only  be  visited  monthly,  and  it  would  then  obviously 
be  impossible  to  separate  the  yield  of  snow,  rain,  &c. ;  therefore,  for  the  sake  of  uniformity, 
all  must  be  taken  together,  and  as,  except  by  watching  all  night,  it  is  never  possible  to  be 
certain  that  small  amounts  are  wholly  dew,  it  is  best  to  count  all  entries  of  "01  in  or 
upwards  as  days  with  rain. 

19.  Dotibtful  Entries. — Whenever  there  is  the  least  doubt  respecting  the  accuracy  of 
any  observation,  the  entry  should  be  marked  with  a  ?,  and  the  reason  stated  for  its  being 
placed  there. 

20.  Breakage. — The  Editor  has  no  desire  to  supply  rain  gauges  or  glasses,  or  in  any 
way  to  undertake,  or  interfere  with,  that  which  is  the  business  of  opticians  ;  but  the 
continuity  and  permanent  accuracy  of  the  records  of  his  correspondents  is  to  him  of  such 
importance,  that  he  deems  it  advisable  to  announce  that  any  assistance  in  his  power  is 
always  at  their  service. 

21.  Leakage.-  Ohseryers  should  test  their  gauges  occasionally  to  see  that  the  amount 
collected  is  neither  increased  nor  decreased  by  leakage. 


THEEMOMETEE   SCREENS 

During  the  last  lialf  century  it  has  been  increasingly  recognised  that  it 
is  useless  to  have  accurate  thermometers,  and  to  aim  at  comparing  climates, 
unless  the  thermometers  are  placed  under  similar  conditions  at  the  two  or 
more  localities  which  it  is  desired  to  compare.  The  first,  in  order  of  date, 
of  the  special  screens  designed  for  this  purpose  was  erected  about  1841  at 
the  Eoyal  Observatory,  Greenwich  ;  it  is  generally  known  as 

Glaisher's  Stand 

It  consists  of  one  horizontal,  one  vertical,  and  two  sloping  boards.  It  is 
made  so  that  it  can  be  turned  round,  and  thus  the  face  on  which  the  thermo- 
meters hang  kept  away  from  the  sun,  and  with  three  thicknesses  of  wood 
and  two  layers  of  air  between  the  sun's  rays  and  the  thermometers.  This 
pattern  is,  in  order  to  secure  continuity  of  record,  still  retained  at  Greenwich 
and  at  some  other  stations.  It  was  formerly  general  at  the  stations  of  the 
British  Meteorological  Society  and  at  those  established  by  the  Eoyal 
Engineers,  but  is  now  rare,  as,  though  a  great  advance  upon  anything  up- 
to  the  date  of  its  construction,  it  is  found  to  have  the  following  disad- 
vantages, {a)  It  does  not  prevent  rain  and  snow  falling  on  the  ther- 
mometers, (b)  the  turning  two  or  three  times  a  day  is  troublesome,  and  if 
forgotten  the  thermometers  may  be  exposed  to  the  direct  rays  of  the  suji, 


170 


HYGIENE 


(c)  the  thermometers  are  warmed  by  radiation  from  the  ground  and  neigh- 
bouring objects,  unless  surrounded  by  quite  a  large  space  of  grass. 

Stevenson's  Screen 

I  cannot  trace  the  precise  history  of  this  pattern.  In  an  address  to  the 
Meteorological  Society  of  Scotland,  delivered  January  14,  1857,  by  Dr.  Stark, 
F.R.S.E.,  the  secretary,  there  is  the  following  paragraph  : — • 

The  Committee  have  had  long  and  earnest  discussions  relative  to  the  mode  of  exposing 
the  instruments  to  the  weather.  It  is  quite  apparent  that,  if  we  wish  comparable  results, 
the  instruments  must  be  similarly  exposed  ;  and  the  Committee  have,  meanwhile,  recom- 
mended that  the  instruments  should  be  exposed  in  a  box,  with  double  open  lonvre-boarded 
sides,  1^  inch  being  between  the  sides,  with  a  sloping  roof  to  carry  off  the  rain,  and 
raised  4  feet  from  the  ground.  To  suit  instruments  of  all  sizes  it  is  convenient  to  have 
the  inner  box  about  18  inches  in  internal  width  by  14  inches  in  depth  and  8  inches  in 
breadth  ;  and  it  may  either  be  fixed  in  an  open  spot  over  grass,  or,  if  a  low  window  with  a 
northern  exposure  can  be  had,  it  may  be  fixed  in  front  of  it,  and  the  side  next  the  window 
may  be  made  single,  and  to  open  downwards,  so  that,  when  opened,  the  door  would  rest  on 
the  window  sill. 

It  is  a  pity  that  this  description  was  not  accompanied  by  an  engraving  ; 
and  it  is  to  be  noted  that  Mr.  Thomas  Stevenson,  C.E.,  who  eventually 
brought  out  the  Stevenson  Screen,  was  a  member  of  the  committee  in 
whose  name  Dr.  Stark  was  speaking. 

Three  years  later  (March  29,  1860)  the  Council  state  that  boxes  have 
been  erected  at  most  of  the  Society's  stations,  but  that  they  are  not  uniform, 

that  there  is  considerable  difference  of  opinion 
as  to  the  best  form,  that  experiments  were  to  be 
instituted  by  the  secretary  to  ascertain  the  best 
pattern,  and  that  the  Council  hoped  to  publish 
the  results  in  the  next  report.  I  cannot  trace 
auy  record  of  these  experiments,  or  of  their 
result.  In  fact,  the  subject  seems  to  have  slum- 
bered until  June  1864,  when  in  a  paper  in  the 
Journal  of  the  Scottish  Meteorological  Society 
Mr.  Stevenson  gave  a  description  and  sketch  of 
the  stand  almost  precisely  as  it  is  still  made. 
Fig.  70  gives  a  representation  of  it,  which  leaves 
only  one  point  needing  mention — namely,  that 
the  Venetians  are  double,  falling  both  inside  and 
outside,  and  with  half  an  inch  between  them  at 
their  highest  points.  They  are  on  one  frame  cut 
herring-bone-wise,  which  not  only  saves  cost,  but 
also  bulk,  and  the  hollow  between  the  two  sets 
causes  nearly  all  rain  to  drop  through  instead  of 
running  up  one  slope  and  down  the  other,  and 
being  thence  blown  on  to  the  thermometers. 
This  is  not  a  perfect  stand  suitable  for  all  cli- 
mates ;  no  such  stand  has  been  devised,  but  the 
Stevenson  certainly  seems  well  adapted  for  this  country,  and  is  rapidly  sup- 
planting all  others. 

MoNTSouKis  Theemometee  Stand 

Fig.  71  represents  the  pattern  of  stand  generally  used  in  France.  The 
southern  sun  is  shut  off  by  the  double  roof  A,  morning  and  evening  sun  by 
the  wings  B  C.    As  already  stated,  thermometers  in  France  are  not  mounted 


METEOROLOGY 


111 


on  slabs  as  in  England,  but  the  maximum  and  minimum  can  be  seen  hanging 
at  a  and  h,  while  other  instruments  are  placed  at  d  and  e.     It  will  be  noticed 
that  the  stand  is  approached  by  several  steps,  rendered  necessary  by  the  fact 
that  in  that  country  the  ther- 
mometers are  usually  8  or  9 
feet  above  the  ground,  instead 
of  4  feet  as  in  England. 

I  have  dealt  rather  fully 
with  the  previous  instruments 
because  they  are  the  funda- 
mental ones  for  all  climatic 
work,  and  the  very  fact  that 
I  have  done  so  will  enable  me 
to  dispose  of  some  of  the 
other  instruments  very  briefly. 

SUNSHINE 

Although  means  of  re- 
cording approximately  the 
duration  of  sunshine  were 
devised  more  than  thirty 
years  since,  the  instrument 
has  only  lately  been  brought 
into  a  compact  and  handy 
form,  therefore  the  general 
use  of  sunshine  recorders  is 

much  more  recent.   At  present  (owing  chiefly,  it  is  stated,  to  the  cost  of  procur- 
ing and  grinding  good  glass  spheres)  sunshine  recorders  are  rather  expensive. 


but,  partly  perhaps  from  their  novelty,  their  adoption  is  becoming  fi-equent. 
There  are  many  patterns ;  one  available  for  the  tropics,  or  indeed  for  any 


172 


HYGIENE 


latitude,  is  shown  in  fig.  72,  p.  171.  The  principle  is  very  simple  ;  whenever 
the  sun  shines  brightly,  its  rays,  focussed  by  the  sphere,  fall  on  a  strip  of 
cardboard  and  burn  a  hole  ;  as  the  world  turns  round,  if  the  sun  continue  to 
shine,  the  hole  is  elongated  and  becomes  a  slit,  which  if  no  clouds  intervene 
will  continue  till  nearly  sunset.  The  length  charred  is  theiefore  a  distinct 
measure  of  the  duration  of  sunshine. 

Another  arrangement  for  obtaining  analogous  records,  is  by  placing  sensi- 
tised photographic  paper  in  the  box  shown  in  fig.  73.  The  sun  shines  in 
through  a  tiny  hole,  and  while  shining  acts  on  the  paper,  the  photographic 
trace  on  wliich  is  fixed  by  wasliing  in  clean  water,  and  the  record  can  then 
be  read  off.^ 

To  distinguish  between  the  two  methods  it  has  been  proposed  to  call  the 
photographic  one  swnligJit  records,  and  the  burnt  ones  snushine  records. 


SOLAE   EaDIATION 

To  determine  the  heating  power  of  the  sun's  rays  appears  at  first  sight 


Fig.  73. 
extremely  easy ;  put  a  maximum  thermometer  in  the  sunshine  and  you  have 
it  at  once.  Oh  no,  very  far  from  it.  If  your  thermometer  be  clean  and 
bright,  the  mercury  in  it  will  act  as  a  spherical  mirror,  and  instead  of  absorb- 
ing the  sun's  heat  rays  will  reflect  them.  Then  make  the  bulb  of  blaok 
glass  ;  still  the  vitreous  surface  will  act  as  a  partial  reflector.  Then  coat  it 
with  lampblack;  still  two  evils— (a)  the  first  shower  will  wash  it  off; 
(b)  unless  part  of  the  stem  be  blackened  as  well  as  the  bulb,  the  cold  stem 
will  chill  the  bulb.  Blacken  both  thermometer  and  part  of  stem,  and  put  it 
inside  a  glass  jacket,  pump  out  as  much  air  as  you  can,  and  having  done  so 
seal  the  tube  hermetically.  Those  are  the  reasons  for,  and  the  stages  by 
which  the  black  bulb  in  fig.  75  was  arrived  at.  But  we  are  still  far  from 
obtaining  the  true  heat  of  the  sun's  rays.  Putting  the  thermometer  into  the 
vacuum  jacket  not  only  protects  it  from  rain  but  largely  from  another  very 
important  influence — wind.  Evidently  the  reading  of  a  naked  black  bulb 
thermometer  is  intermediate  between  that  produced  by  the  sun  and  that  of 

'  Fig.  74  represents  a  form  of  this  intended  for  any  latitude. 


METEOBOLOGY 


173 


the  air  in  contact  with  it ;  the  stronger  the  wind  the  more  rapidly  will  fresh 
particles  of  air  impinge  upon  the  thermometer  bulb  and  the  lower  will  it 
read.  Even  the  jacket  does  not  wholly  abolish  this  evil,  because  tlie  wind 
cools  the  glass  jacket,  and  the  jacket  and  the  bulb  interchange  heat  by  radia- 
tion, and  therefore  part  of  the  influence  of  wind  remains.  Then  there  is 
another  difficulty.  Suppose  that  on  two  consecutive 
days  the  black  bulb  in  vacuo  read  128°,  but  that 
the  temperature  of  the  air  on  the  first  day  was 
70°,  on  the  second  80° ;  one  sees  at  once  that 
the  sun's  rays  must  have  been  more  powerful  on 
the  first  day  than  on  the  second,  because  on  the 
first  they  raised  the  black  bulb  68°  above  the  air 
temperature,  and  on  the  second  only  48°.  At 
present  the  best  plan  is  to  have  two  thermometers 
as  nearly  identical  as  possible,  except  that  the  bulb 
and  part  of  the  stem  of  one  is  coated  with  lamp- 
black, and  the  other  is  left  bright ;  both  are  in 
vacuum  jackets,  both  on  one  post,  pointed  in  the 
same  direction  (preferably  to  S.E.)  and  both  four 
feet  above  grass,  and  to  consider  as  the  amount  of 
solar  radiation  the  excess  (in  degrees)  of  the  black 
bulls  above  the  bright  bulb  thermometer. 

Tereestrial  Eadiation 

Everybody   does  not  know,  what    is  however 
quite  true,  that,  as  a  rule,  a  grass  plot  is  consider-  Fig.  75. 

ably  colder  than  a  flower  bed  or  a  gravel  walk,  and 

that  all  are  considerably  colder  than  the  air  three  or  four  feet  above  them. 
This  cooling  is  due  to  the  rapidity  with  which  (when  there  are  no  clouds) 
grass  radiates  heat  into  space.    The  amount  of  terrestrial  radiation  is  therefore 


Fig.  76. 


nearly  proportional  to  the  absence  of  cloud.  It  is  determined  by  placing 
Casella's  modification  of  Eutherford's  minimum  thermometer  (fig.  76)  on  a 
grass  plot,  and  noting  the  difference  between  its  reading  and  that  of  the 
minimum  in  the  Stevenson  screen. 


Earth  Temperature 

The  broad  general  features  of  earth  temperature  are,  that  at  depths 
of  a  few  inches  the  temperature  does  not  differ  very  widely  from  that  of 
the  air,  but  as  the  depth  increases  the  amphtude  of  the  daily  and  seasonal 
changes  decreases,  and  the  latter  also  suffer  retardation,  so  that  at  two 
or  three  feet  the  minimum,  instead  of  occurring  in  the  beginning  of 
January,  falls  late  in  February,  and  the  maximum,  instead  of  July  16,  falls 
late  in  August,  and  the  maximum  is  so  much  lov/er  and  the  minimum  so 
much  higher  that  the  range  there  is  less  than  half  what  it  is  at  the  surface. 


174 


HYGIENE 


-v-H" 


At  ten  feet  the  retardation  amounts  to  nearly  three  months,  and  the  range  is 
reduced  to  about  8°-0,  and  at  25  feet  the  range  is  only  about  3°,  and  the 
minimum  is  retarded  until  June  and  the  maximum  till  December,  so  that 
probably  at  about  35  feet,  where  the  range  is  reduced  to  1°,  the  maximum 
occurs  at  the  date  of  greatest  winter  cold  and  the  minimum  at  that  of 
maximum  summer  heat. 

The  observation  of  earth  temperature  was  formerly  difficult  and  the  ther- 
mometers themselves  were  extremely  delicate  and  costly,  as  the  old  plan  was  to 
have  a  long  and  fine  bore  tube  with  a  large  bulb,  and 
bury  all  but  the  upper  portion  in  a  pit,  leaving  the 
scale  at  the  top  visible,  so  that  the  thermometer  could 
be  read.  Anyone  can  realise  the  difficulty  and  danger 
of  breakage  attending  the  construction,  transport, 
and  fixing  of  a  thermometer  25  feet  long,  with  a 
heavy  bulb  at  the  end  of  it.  The  modern  plan  (fig. 
77)  is  to  close  the  bottom  of  a  piece  of  stout  iron  tube, 
to  drive  it  or  bary  it  in  the  ground  to  the  desired 
depth,  and  to  lower  into  it,  by  a  cham,  a  slow-action 
thermometer  (i.e.  one  with  a  large  bulb  and  coated 
with  non-conducting  material  so  that  its  indications 
will  not  change  while  being  raised),  which  is  hauled 
up  by  the  chain  whenever  a  reading  has  to  be  taken. 
In  short  ones,  like  fig.  77,  the  thermometer  is  let 
into  a  stick  attached  to  the  covering  cap.  Another 
immense  advantage  of  the  new  plan  is  that  the  ther- 
mometer can  be  verified  whenever  desired.  The  old 
thermometers,  once  placed,  could  not  be  raised,  and 
their  errors  were  never  known. 


WIND 

DiBECTION 

As  regards  direction  it  is  questionable  whether 
for  sanitary  and  hygienic  purposes  any  apparatus  is 
needed ;  there  is  no  vane  so  sensitive  and  true  as 
the  smoke  from  a  chimney,  and  when  an  observer  has  once  fixed  accurately 
the  precise  position  of  his  meridian,  nothing  else  is  required  but  care  and 
common  sense. 

It  may  be  well  to  mention  the  very  easiest  way  of  finding  the  meridian, 
at  any  place  where  true  local  time  is  known.  The  sun  is  due  south  at  noon 
or  within  a  minute  thereof  during  the  following  periods  : 

April  11th  to  18th. 

June  9th  to  18th. 

August  28th  to  September  3rd. 

December  22nd  to  25th. 

If,  therefore,  a  pole  be  erected  vertically  as  tested  by  a  plumb  line,  the 
shadow  from  it  will  fall  true  N.W.  at  9  a.m.,  N.  at  noon,  and  N.E.  at  3  p.m. 
The  (in  all  other  respects)  very  advantageous  spread  of  uniform  time,  e.g. 
Greenwich  time,  throughout  England  and  Wales,  and  Paris  time  through- 
out France,  has  led  to  local  time  being  lost  sight  of.  It  can  always  be 
obtained  from  uniform  time  by  correcting  for  longitude  as  in  the  following 
case. 


Fig.  77. 


METEOBOLOGY 


175 


What  is  the  local  time  at  Bath  when  it  is  9  a.m.  Greenwich  time  ? 
Eeference  to  any  map  will  show  that  Bath  is  2°  20'  W.  of  Greenwich. 
Degrees  and  seconds  of  longitude  multiphed  by  4  give  minutes  and  seconds 
of  time. 

Then  2°  20' 

4 

9m.  20s. ; 
and  as  Bath  is  W.  of  Greenwich,  local  time  there  is  earlier  than  at  Green - 
•  wich,  therefore  at  Bath  9.0  Greenwich  time  corresponds  to  8h.  50m.  40s. 
local' time.     In  other  words,  on  the  dates  above  set  out,  the  sun  at  Bath  is 
due  south  at  Oh.  9m.  20s.  Greenwich  time. 

It  may  be  thought  that  it  is  easier  to  lay  down  the  true  cardmal  pomts 
by  the  Pole  star,  which  can  be  seen  any  starlight  night,  and  which  is  never 
very  far  away  from  true  N.,  but  I  do  not  think  so.  Others  may  say  why  not 
do  it  by  a  compass,  allowing  for  variation.  If  the  observer  is  sure  that  he 
knows  the  variation,  if  he  duly  allows  for  it  and  does  not  apply  it 
with  the  wrong  sign,  well  and 
good;  but  these  hints  are  not 
written  for  experts  (had  they 
been,  I  should  have  suggested 
the  method  of  equal  altitudes), 
but  merely  to  point  out  to  be- 
ginners the  path  which  contains 
the  fewest  pitfalls. 

The  motion  of  clouds  is  by 
no  means  to  be  ignored,  but  it 
will  be  found  that  only  the  very 
lowest  can  be  taken  as  indicating 
surface  wind.  The  motion  of 
high  clouds  is,  however,  inter- 
esting, and  at  times  indicates 
that  to  which  the  surface  wind 
will  gradually  shift. 

FoKCE  OK  Velocity  of  Wind 

This  is  a  rather  difficult  sub- 
ject, and  one  at  present  in  a  state 
of  confusion.  It  is  generally 
stated  that  what  is  known  as 
the  Eobinson's  cup  anemometer 
was  first  made  known  in  1850 
by  a  paper    published  in  the 

Trans.Boy.Irish  Acad,  in  1855;  but  this  is  not  correct,  as  the  Report  of 
the  British  Association,  1846,  part  2,  p.  Ill,  shows  that  (1)  the  original 
suggestion  was  not  Robinson's,  but  Edgeworth's  ;  and  (2)  that  the  instru- 
ment was  at  work  in  1846,  four  years  before  the  above  paper  was  written. 
That,  however,  is  merely  the  correction  of  a  little  bit  of  false  history. 

Eobinson's  anemometers,  being  those  by  far  most  generally  used,  claim  a 
few  words  of  description  and  comment.  Fig.  78  shows  the  simplest  form. 
From  whatever  direction  the  wind  may  blow  it  will  meet  the  hollow  face  of 
two  cups  and  the  rounded  face  of  two  others  ;  it  will  exert  more  force  upon 
the  former  than  upon  the  latter,  and  therefore  it  will  cause  the  whole  four  to 
rotate  ;  and  the  stronger  the  wind  the  faster  will  be  the  rotation.     On  the 


17G  HYGIENE 

shaft  which  carries  these  four  arms  there  is  au  endless  screw  which  works 
in  teeth  cut  in  the  circumference  of  the  dials,  and  so  (by  arrangements,  into 
the  detail  of  which  I  need  not  enter)  the  hands  indicate  on  the  dial  the  number 
of  miles  of  wind  which  have  passed  since  the  previous  reading.  The  funda- 
mental principle  upon  which  these  instruments  are  graduated,  is  that  the 
cups  move  with  one-third  of  the  velocity  of  the  wind — i.e.  that  if  the  centres 
of  the  cups  are  1*12  feet  apart  each  revolution  would  correspond  to  3*52  feet 
of  motion,  and  (if  the  factor  be  really  3)  to  10-56  feet  of  wind,  then 
(10-50  X  500=5280  ft.=l  mile)  500  rotations  would  indicate  the  passage  of 
one  mile  of  wind. 

I  said  that  this  subject  is  in  a  state  of  confusion  ;  it  is  so  for  this  reason, 
that  it  has  been  proved  that  the  factor  is  not  3,  but  something  between 
2  and  3,  probably  about  2^.  This  may  appear  a  small  matter,  but  it  is 
not;  its  effect  is  that  all  wind  velocities  are  reported  greater  than  they 
really  are — a  wind  of  50  miles  an  hour  is  called  one  of  60  miles  an  hour, 
and  so  on.  Besides  this  fundamental  error  there  are  others,  such  as  the 
retardation  due  to  friction,  which  varies  with  the  velocity  ;  at  very  low 
velocities,  two  or  three  miles  an  hour,  the  friction  is  so  nearly  equal  to  the 
wind  force  that  many  anemometers  stand  still ;  but,  on  the  other  hand, 
when  the  wind  gets  to,  say,  fifty  miles  an  hour  and  the  cups  have  to  make 
seven  complete  rotations  in  each  second  of  time,  friction  becomes  relatively 
unimportant.  And  it  is  not  merely  legitimate  friction  from  which  ane- 
mometers suffer.  I  have  seen  the  anemometer  on  an  observatory  (where 
there  was  no  lack  of  money)  coated  with  a  sticky  compound  of  soot  and  oil 
quite  half  an  inch  thick — that  was  not  fair  play.  I  have  photographs  of  the 
anemometers  at  several  mountain  observatories  quite  unrecognisable  under 
their  mantle  of  hoar  frost.  Evidently  the  indications  of  instruments  in  such 
circumstances  are  not  worth  the  paper  upon  which  they  are  recorded — still 
less  are  they  worth  reducing  and  publishing. 

Another  great  difficulty  with  anemometers  is  that  of  finding  a  suitable 
position  for  them.  No  one  can  be  found  to  approve  the  existing  practice  of 
meteorologists  with  respect  to  anemometry,  and  yet  hardly  any  one  has  the 
courage  to  insist  on  a  new  departure.  Almost  universally  in  this  country 
and  on  the  Continent  the  anemometer  is  mounted  on  the  highest  part  of  the 
observatory,  with  no  regard  to  what  height  it  may  be  above  the  ground,  nor 
to  the  shape  of  the  building.  Now  it  is  well  known  and  obvious  that  air 
currents  are  retarded  by  friction,  and  that  therefore  the  greater  the  height 
above  the  ground  the  greater  the  freedom  with  which  the  wind  moves,  and 
therefore  the  greater  its  velocity.  And  it  is  equally  obvious  that  if  a  wind 
current  meets  a  building,  it  cannot  go  through  it,  and  must  therefore  pass  it 
either  laterally  or  over  the  top  ;  hence  it  is  that  the  wind  at  some  feet  above 
the  top  of  the  building  is  generally  greater  than  that  of  the  true  air  current 
at  that  level. 

The  foregoing  remarks,  while  probably  useful  historically,  are  also  designed 
to  act  as  warnings  to  those  who  may  think  that  if  they  go  to  a  good  optician 
for  a  Eobinson's  anemometer  and  then  fix  it  in  position,  they  will  ex  neces- 
sitate have  an  accurate  record  of  the  velocity  of  the  wind.  Besides  the  false 
factor  (I  believe  no  one  has  yet  abandoned  the  3  to  1),  they  must  see  that  it 
is  in  a  thoroughly  open  position,  not  less  than  ten  feet  above  ground,  with 
no  buildings  near  it,  and  that  it  is  kept  scrupulously  clean  and  frequently 
suppHed  with  fresh  oil. 

Occasionally  the  wind's  force  is  reported  in  lbs.  per  square  foot :  tliis  is 
sometimes  obtained  from  a  pressure  anemometer  (of  which  the  best  known 
is  Osier's)  and  sometimes  computed  from  the  recorded  velocity  on  the  assump- 


Beaufort  Scale 

Description 

0 

Calm 

1 

Light  air 

2 

Light  breeze 

3 

Gentle  breeze 

4 

Moderate  breeze 

5 

Fresh  breeze 

6 

Strong  breeze 

7 

Moderate  gale 

8       • 

Fresh  gale 

9 

Strong  gale 

10 

Whole  gale 

11 

Storm 

12 

Hurricane 

METEOEOLOGY  177 

tion  that  the  square  root  of  200  times  the  pressure  m  pounds  equals  the 
velocity  in  miles  per  hour — i.e. 

\/200P  =  V,  or  conversely,  V^  x  '005  =  P. 

But  this  factor  of  200  is  as  doubtful  as  that  of  3  for  the  ratio  of  Robinson's 
cups. 

There  are  many  tables  given  for  roughly  estimating  the  force  of  the  wind, 
but  they  differ  greatly.  I  think  that  the  following,  given  by  Mr.  R.  H.  Scott, 
F.R.S.,  in  his  Instructions,  is  the  best,  but  possibly  the  velocities  may  be 
considered  too  great  when  the  3  is  finally  replaced  by  2-5  or  whatever  is  the 
best  value.     The  90  miles  might  then  come  down  to  75. 

Velocity  in  miles  per  hour 
3 
8 
13 
18 
23 
28 
34 
40 
48 
56 
65 
75 
90 


AMOUNT   OF   CLOUD 

It  has  not  yet  become  the  practice  to  record  this  except  by  estimation, 
but  it  is  surprising  with  what  accuracy  these  estimates  are  made.  As  a  rule 
observers  ignore  from  the  horizon  up  to  about  20"^,  and  confine  their  estimate 
to  the  zenith  and  70°  from  it  towards  the  horizon.  This  space  is  supposed 
to  be  divided  into  10  parts  ;  if  there  is  not  a  trace  of  cloud,  the  amount  is  0  ; 
if  there  are  equal  amounts  of  blue  sky  and  of  cloud,  5  ;  if  entirely  overcast, 
10.  It  is  not  so  easy  to  determine  the  amount  after  dark,  but  an  observer 
soon  learns  the  constellations,  and  uses  the  absent  stars  as  evidence  of  present 
cloud. 

FOEMS   OF   CLOUD 

This  is  one  of  the  branches  of  meteorology  in  a  transitional  state.  At 
the  beginning  of  this  century  Luke  Howard,  F.R.S.,  who  has  been  well 
called  the  Father  of  English  meteorology,  wrote  an  essay  upon  the  subject, 
proposed  a  nomenclature  and  submitted  a  series  of  descriptions  of  clouds, 
which,  in  spite  of  the  enormous  advances  in  other  branches  of  meteorology, 
still  hold  the  first  rank.  Even  photography  has  not  yet  helped  very  much, 
because  it  of  course  has  the  difficulty  of  producing  similar  effects  by  white 
clouds  and  their  blue  background.  Much  has  been,  and  is  being,  done, 
especially  in  Sweden,  France,  and  England,  and  various  alterations  of 
Howard's  classification  have  been  suggested,  but  not  one  of  the  new  pro- 
posals has  met  with  general  adoption,  and  therefore  I  quote  only  Howard's, 
and  in  his  own  words. 

CiBEUs  {mares'  tails — the  loftiest  cloud;  Mr.  Glaisher,  F.R.S.,  when 
five  or  six  miles  high,  in  Coxwell's  balloon,  saw  cirri  far  above  him). — Parallel, 
flexuous,  or  diverging  fibres,  extensible  by  increase  in  any  or  in  all  direc- 
tions. 

VOL.  I.  N 


178  HYGIENE 

CiKRO-cuMULus  {mackcvol  shj). — Small,  well-defined  roundish  masses 
in  close  horizontal  arrangement  or  contact. 

CiEEO-STKATUs. — Horizontal  or  slightly  inclined  masses,  attenuated 
towards  a  part  or  the  whole  of  their  circumference,  hent  downward  or  undu- 
lated ;  separate  or  in  groups  consisting  of  small  clouds  havmg  these  characters. 

The  foregoing  are  the  clouds  chiefly  prevalent  at  great  heights ;  the 
following  are  usually  lower. 

Steatus  (ground-fog). — A  widely  extended  continuous  horizontal  sheet, 
increasing  from  below  upward. 

Cumulus  (mountain-like  clouds,  often  toith  a  silver  lining).  Convex  or 
conical  heaps;  increasing  upward  from  a  horizontal  base. 

CuMULO-STEATus. — The  cirro-stratus  blended  with  the  cumulus,  and 
either  appearing  intermixed  with  the  heaps  of  the  latter,  or  superadding  a 
wide-spread  structure  to  its  base. 

Nimbus. — The  rain  cloud.  A  cloud  or  system  of  clouds  from  which  rain 
is  falling.  It  is  a  horizontal  sheet,  above  which  the  cirrus  spreads,  while  the 
cumulus  enters  it  laterally  and  from  beneath. 

MISCELLANEOUS   PHENOMENA 

Under  this  head  I  purpose  giving  merely  a  few  hints  respecting  pheno- 
mena, which  mostly  can  be  observed  without  instruments,  or  at  any  rate 
without  those  usually  regarded  as  meteorological  ones. 

Snow. — In  sharp  frost  the  patterns  of  snow  crystals  are  frequently  of 
exquisite  beauty.  The  best  way  to  see  them  is  to  expose  slabs  of  coloured 
glass  ;  when  these  become  cold,  and  the  air  is  below  32°,  crystals  will  remain 
unchanged  for  hours,  and  if  care  be  taken  not  to  breathe  upon  them,  they 
can  be  examined  and  drawn  with  perfect  ease.  Directly  the  temperature 
rises  all  their  beauty  vanishes.  Their  size  varies,  but  is  generally  from  ;i^th 
to  T^ths  of  an  inch  in  diameter. 

Hail. — This  varies  much  ;  probably  according  to  the  conditions  of  its 
formation ;  sometimes  it  is  so  soft  as  to  resemble  a  soft  snowball ;  sometimes 
it  is  very  hard  crystalline  ice  ;  sometimes  the  stones  are  formed  of  alternate 
layers  of  clear  and  opaque  ice.  When  the  hail  is  very  soft,  it  is  frequently 
pyramidal  in  shape,  and  not  infrequently  radial  (like  iron  pyrites)  in  its 
texture  and  cauliflower-like  at  its  base,  giving  in  short  the  idea  of  a  ball 
which  had  split  up  into  segments.  There  was  a  wonderful  fall  of  this  kind 
in  and  near  London  at  3.15  p.m.,  March  8, 1857.  Mr.  Glaisher  observed  and 
photographed  some  of  the  stones  at  Greenwich,  and  I  examined  those  which 
fell  near  Buckingham  Palace  ;  at  these  widely- separated  places  the  fall  was 
very  similar,  the  stones  (only  happily  they  were  very  soft)  being  about  one 
inch  long  and  |  inch  in  diameter  at  their  base.  Howard  reports  a  some- 
what similar  fall,  but  of  stones  or  rather  snow  pyramids  of  little  more  than 
half  the  above  dimensions.  Pyramidal  soft  hail  is  common,  but  I  have  never 
seen  or  heard  of  any  case  like  that  of  1857.  When  exceptional  hailstorms 
occur,  prompt  attention  should  be  given  to  weighing  accurately  some  of  the 
largest  stones  that  can  be  found.  Accurate  weight  is  the  most  essential 
feature,  next  to  that  shape  and  size,  then  structure,  whether  clear  or  opaque, 
number  of  alternate  layers,  &c.  Then  evidence  should  be  collected  illus- 
trative of  the  force  of  fall ;  this  is  partly  afforded  by  the  greatest  thickness 
of  glass  broken,  by  the  indentation  of  zmc  or  corrugated  iron  roofing,  by 
damage  to  plants,  poultry,  &c.  It  used  to  be  stated  that  hail  never  fell  at 
night ;  this  is  not  now  asserted,  but  it  is  so  much  more  rare  by  night  than  by 
day  that  nocturnal  hail-falls  should  always  be  fully  reported. 


METEOBOLOGY  17^ 

Thunderstorms.— Full  instructions  upon  observing  thunderstorms  and 
lightning  having  been  issued  by  the  Koyal  Meteorological  Society,  it  is  not 
necessary  to  dwell  at  length  upon  the  subject.  Briefly  it  comes  to  this— 
note  the  time  of  first  thunder,  most  thunder,  and  last  thunder,  and  similarly 
of  hghtning— notice  the  shortest  time  interval,  i.e.  the  interval  between 
seeing  the  hghtning  and  hearing  the  thunder  belonging  to  that  flash— roughly, 
each  five  seconds'  interval  corresponds  to  a  distance  of  a  mile.  If  any  object 
is  struck,  collect  as  full  details  as  practicable.  As  regards  human  beings 
killed  by  hghtning  there  is  much  to  be  learned,  for  the  marks  on,  and 
changes  in,  the  body  vary  immensely—  whether  they  depend  on  the  intensity 
of  the  shock,  on  the  state  of  the  skin  as  to  perspiration  (I  believe  that  not 
infrequently  vapour  saves  a  man's  life— it  acts  as  a  conductor— is  so  electri- 
fied that  it  strips  the  man  of  his  clothes,  but  it  keeps  the  charge  outside  his 
body,  and  so  saves  his  life).  This  question  of  perspiration  is  very  important, 
because  at  present  there  is  no  evidence  whether  the  vapour  is  converted  into 
high-pressure  steam  by  heat,  or  whether  the  water  particles  are  repelled  by 
becoming  similarly  electrified.  I  think  that  the  latter  is  the  more  probable, 
but  the  observed  fact  is  that  persons  whose  feet  are  hot  generally  have  their 
boots  burst  open  and  flung  from  their  feet,  while  they  personally  suffer  Httle 
hurt.  Evidence  as  to  the  thickest  piece  of  metal  fused  by  hghtning  is  very 
much  wanted. 

Ozone. — Thirty  years  ago  no  meteorological  station  was  considered  to  be 
properly  equipped  without  a  box  of  ozone  test  papers — strips  of  foolscap  paper 
dipped  in  iodide  of  potassium  and  starch.  During  the  cholera  epidemics  of 
1849  and  1854,  great  attention  was  given  to  the  subject,  and  I  personally 
think  that  it  is  a  pity  that  the  observations  were  given  up.  It  is  true  that  the 
papers  were  not  uniform,  that  distinguished  chemists  scorned  the  plan,  and 
that  Dr.  Fox  wrote  a  large  and  handsome  book  which  killed  the  old  method, 
but  did  not,  I  believe,  induce  a  single  observer  to  adopt  the  new  one  which 
he  recommended.  I  do  not  for  a  moment  enter  the  lists  with  either  Dr.  Fox 
or  any  other  chemist ;  very  possibly  the  discoloration  of  the  test  papers  was 
not  due  to  ozone  at  all.  I  admit  all  that,  but  I  will  report  very  briefly  what  I 
did  in  1856  or  1857,  and  leave  it  to  the  reader  to  say  whether  or  not  it  is  pro- 
bable that  perseverance  in  the  direction  then  commenced  might  not  have 
been  rewarded  by  progress  in  sanitary  work.  I  cut  up  a  set  of  ozone  papers 
so  that  portions  of  one  small  strip  were  simultaneously  exposed  at  several 
stations,  two  in  the  heart  of  London  and  Westminster  respectively,  and  the 
other  four  or  five  were  exposed  in  the  suburbs.  A  month's  papers  were  sent 
out  at  once  all  ready  dated ;  at  the  end  of  the  month  all  came  back  to  me. 
Except  from  smoke,  there  was  not  a  single  day  on  which  the  papers  exposed 
in  town  were  discoloured.  The  suburban  ones  varied,  but  according  to  a 
regular  law  the  papers  in  the  S.W.  suburbs  showed  ozone,  or  rather  I  would 
say  discoloration,  with  wind  from  S.W.,  but  when  the  wind  was  N.  or  E.  and 
had  to  pass  over  the  metropolis  there  was  no  discoloration ;  and  so  all  round. 
Winds  from  the  country  coloured  the  papers,  wind  which  had  passed  over  the 
metropolis  never  did. 

Fog. — This  is  one  of  the  meteorological  phenomena  hitherto  neglected  ; 
it  is  entered  in  the  registers,  and  sometimes  the  word  dense  is  added,  but  that 
is  all.  It  seems  to  me  imperative  that  there  should  be  some  scale  of  intensity 
adopted  for  fog,  just  as  there  is  for  amount  of  cloud.  Six  years  since,  I 
wrote  a  strong  plea  for  the  establishment  of  fog  gauges,^  and  suggested  the 
erection  of  a  slab  painted  as  per.  fig.  79,  p.  180,  No.  1  to  be  :^  inch  broad  and 
the  higher  numbers,  \,  1,  2,  and  4  inches  respectively,  the  scale  to  be  20  ft. 

'  Symons's  Meteorological  Magazine,  xvii.  17. 

n2 


1     2 

5 

4 

5 

1 

1 

1 

■ 

NU 

^/^ 

180  HYGIENE 

from  the  observer,  and  the  amount  of  fog  recorded  to  be  that  of  the  thinnest 
line  which  could  be  seen.  I  do  not  suggest  that  the  plan  is  perfect,  but 
regret  that  no  better  has  been  proposed,  and  that  to  my  knowledge  only  one 

observer  has  adopted  it. 
We  shall  certainly  not 
learn  anything  satisfac- 
torily respecting  fog  dis- 
tribution until  some  such 
scheme  is  adopted. 

Optical  Phenomena. 
— There  is  much  for  the 
meteorologist  to  do  under 
this  head,  but  as  no  one 
could  at  present  prove  the  relation  between,  say,  aurora  and  public  health,  it, 
and  such  other  subjects  as  haloes,  coronas,  luminous  meteors,  the  three 
varieties  of  the  rainbow,  &c.,  must  pass  without  notice  here,  the  reader  being 
referred  to  the  short  list  of  useful  books  at  the  end  of  this  article  if  he 
desires  to  pursue  the  subject. 

Verification  of  Instruments 

It  is  always  best  to  insist  upon  instruments  being  accompanied  by  a 
certificate  of  verification,  the  cost  of  which  (except  for  barometers)  rarely 
exceeds  half-a-crown. 

OBSEEVATION  HOUES 

These  vary  in  different  countries  ;  in  the  British  Isles  the  hours  are  almost 
without  exception  9  a.m.  and  9  p.m.  at  the  first  and  second  order  stations, 
and  9  a.m.  alone  at  the  climatological  and  rainfall  stations.  As  regards  tem- 
perature, it  is  a  curious  fact  that  any  homonymous  hours  such  as  3  a.m.  and 
3  p.Bi.,  4  A.M.  and  4  p.m.,  5  a.m.  and  5  p.m.,  give  an  average  which  does  not 
differ  widely  from  the  mean  of  the  whole  twenty-four  hours,  and  the  same 
is  nearly  true  of  the  mean  of  the  maximum  and  minimum  temperatures  in  a 
Stevenson  screen.  On  the  Continent,  where  people  rise  earlier,  7  a.m.  is  very 
usually  the  time  of  the  first  observation,  followed  by  another  about  1  p.m.  and 
a  third  about  8  p.m.,  but  there  is  much  less  uniformity  than  there  is  in  the 
British  Isles. 

Making  the  Observations 

Many  hints  upon  this  subject  have  already  been  given  ;  it  only  remains  to 
add  a  few  general  ones.  In  the  first  place  never  '  cook  '  an  observation  ;  it  is 
much  better  to  leave  a  blank,  and  to  give  in  the  margin  any  information 
from  which  you  think  that  you  could  'cook'  the  missing  record.  The 
'  cooking,'  if  it  has  to  be  done  at  all,  can  be  done  best  at  the  central  office, 
where  other  records  are  available  for  comparison. 

When  reading  thermometers  look  quite  horizontally  at  them,  otherwise  you 
will  read  them  too  high  or  too  low.  Take  care  that  you  can  look  comfortably 
at  all  parts  of  the  scale  of  your  dry  and  wet  bulb  instruments ;  if  they  are  at 
all  too  high,  provide  a  stool  or  step.  Observations  not  made  comfortably  are 
rarely  made  well. 

Be  punctual ;  do  not  imagine  that  five  minutes  after  time  is  of  no  conse- 
quence, or  you  will  let  the  five  grow  to  ten  and  the  ten  to  fifteen,  and  then 
your  unpunctuality  will  cause  more  harm  than  the  index  error  of  your 
instruments. 


METEOROLOGY  181 

Always  train  at  least  one  other  person  to  observe ;  otherwise,  if  you  are 
absent  or  ill,  your  record  will  be  interrupted,  and  broken  records  are  of 
little  use. 

The  Entry  of  the  Observations 

This  differs  so  much  according  to  circumstances,  that  few  general  rules 
can  be  laid  down.  There  is,  however,  one  often  neglected,  but  which  ex- 
perience shows  to  be  necessary ;  it  is  that  the  observations  should  never  be 
taken  on  a  scrap  of  paper,  an  envelope,  or  a  slate,  i.e.  never  on  anything 
which  is  not  to  be  preserved.  If  observations  are  worth  making,  they  are 
worth  preserving ;  and,  however  much  an  observer  may  intend  to  faithfully 
■copy  the  figures  into  his  permanent  register,  he  may  lose  the  scrap  of  paper, 
smudge  the  slate,  or  make  a  mistake  in  copying.  Memorandum-books  are 
so  cheap  that  there  can  be  no  reason  why  the  original  entries  should  not  be 
neatly  entered  in  pencil  in  readiness  for  copying  in  ink,  and  then  in  any 
doubtful  case  the  original  pencil  entry  can  be  produced. 

The  forms  of  record  employed  by  different  societies,  institutions,  and 
countries  differ  so  considerably,  but  are  all  of  them  so  clearly  arranged,  that 
no  further  explanation  seems  needed  than  that  on  the  forms  themselves. 

The  Publication  of  Observations 

This  also  is  a  subject  upon  which  there  is  little  to  say,  because  it  depends 
so  much  on  the  object  with  which  the  publication  is  to  be  made.  I,  however, 
offer  one  suggestion,  viz.  that  in  many  tables  too  much  prominence  is  given 
to  hygrometric  calculations  of  doubtful  value,  and  too  little  to  daily  and 
monthly  ranges  of  temperature.  I  by  no  means  advise  the  exclusion  of  the 
dew-point  temperature,  or  the  amount  of  humidity ;  but,  knowing  that  the 
foundation  (the  theory  of  the  wet-bulb  thermometer)  is  doubtful,  I  think  that 
space  can  be  employed  to  greater  advantage  than  by  devoting  columns  to 
*  elastic  force  of  vapour,' '  weight  of  vapour  in  a  cubic  foot  of  air,'  '  additional 
weight  of  vapour  required  to  saturate  a  cubic  foot  of  air,'  and '  weight  in  grains 
of  a  cubic  foot  of  air.' 

Lastly,  I  would  urge  that,  wherever  possible,  values  should  be  given  not 
only  in  figures  but  represented  by  curves  and  diagrams. 

SOME  USEFUL  BOOKS  UPON  METEOROLOGY 

(I  purposely  make  this  heading  as  vague  as  possible  because  every  list  of 
the  kind  must  necessarily  be  imperfect.  Where  a  subject  has  a  literature  of 
many  thousand  volumes,  no  two  persons  would  pick  out  the  same  fifty  as 
the  best ;  nay  more,  the  same  person  would  probably  not  twice  select  the 
same  fifty.  It  would  have  been  both  more  easy  and  more  pleasant  to  make 
it  longer,  but  anything  beyond  a  very  short  list  would  be  quite  out  of  place. 
The  title  is  given  in  English  for  all  those  works  of  which  English  translations 
exist.  Where  translations  are  known,  the  language  in  which  they  can  also  be 
obtained  is  indicated  by  a  prefixed  letter.  F= French  ;  G= German ;  S= 
Swedish). 

Instructions  and  Tables 

Abercromby,  Hon,  E. :  Instructions  for  observing  Clouds  (with  photographs).  London, 

1888. 
Blanford.H.  F.,  FJl.S. :  Instructions  to  Meteorological  Observers  in  India.     Calcutta, 

1876. 


182  HYGIENE 

Denza,  F. :  Istruzioni  per  le  osservazioni  meteorologiche  e  per  1'  altimetria  baroma- 

trica  (2  parts).     Torino,  1883. 
Glaisher,  J.,  F.E.S. :  Hygrometrical  Tables.     6th  ed.     Loudon. 
Guyot,  A. :  Tables,  Meteorological  and  Physical.    4th  ed.     Washington,  1884. 
Hann,  J. :  Jelinek's  Anleitung  zur  Ausfiihrung  met.  Beob.    New  edition  in  two  parts- 

Wien,  1884. 
Hazen,  H.A. :  Handbook  of  Meteorological  Tables.     Washington,  1888. 
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Wien,  1876. 
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of  the  Dominion  of  Canada.     Toronto,  1878. 
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Mascart,  E. :  Instructions  Met^orologiquea.     2nd  ed,    Paris,  1881. 
Poey,  A. :  Comment  on  observe  les  Nuages.     3rd  ed.     Paris,  1879. 
Scott,  R.  H.,  F.E.S. :  Instructions  in  the  use  of  Meteorological  Instruments.    London,. 

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accurately  determining  altitudes  barometrically,  with  sundry  useful  tables.    4th  ed. 

London,  1890. 

General  Treatises 

Abbe,  C. :  Treatise  on  Meteorological  Apparatus  and  Methods.     (This  forms  Part  II. 

of  the  Eeport  of  the  Chief  Signal  Officer  U.S.A.  for  1887.)     Washington,  1888. 
Abercromby,  Hon.  E.    Weather.    London,  1887. 

„  ,,  Principles    of    Forecasting    by  means    of    Weather    Charts.. 

London,  1885. 
Bebber,  W.  J.  van  :  Handbuch  der  ausiibenden  Witterungskunde.     Stuttgart,  1885. 
S.  Buchan,  A  :  Handy  Book  of  Meteorology.    2nd  ed.    Edinburgh,  1868. 
„  Introductory  Text  Book  of  Meteorology.     Edinburgh,  1871. 

Capron,  J.  E. :  Auroras,  their  Characters  and  Spectra.    London,  1879. 
Daniell,  J.  F.,  F.E.S. :  Elements  of  Meteorology.     2  vols.    London,  1845. 
G.  Dove,  H.  W. :  Law  of  Storms.     2nd  ed. :  translated  by  E.  H.  Scott.    London,  1862. 
Drew,  J. :  Practical  Meteorology.     2nd  ed.    London,  1860. 

F.  FitzEoy,  Admiral,  F.E.S. :  The  Weather  Book.    London,  1863. 

G.  Foissac,  P. :  De  I'lnfluence  des  Climats  sur  I'Homme.    Paris,  1867. 
Fox,  C.  B.,  M.D. :  Ozone.    London,  1873. 

GuiUemin,  A. :  La  M6teorologie.     Paris,  1885. 

Hann,  J. :  Handbuch  der  Klimatologie.     Stuttgart,  1883. 

Herschel,  Sir  J.  F.  W.,  F.E.S. :  Meteorology.     2nd  ed.    London,  1862. 

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F.E.S.)     London,  1845. 

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Scott.     London,  1879. 
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Schmid,  E.  E. :  Lehrbuch  der  Meteorologie.    Leipzig,  1860. 
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„  Weather  Charts  and  Storm  Warnings.     3rd  ed.    London,  1887. 

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METEOBOLOGY  183 


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Annuaire  de  la  Soci6t6  M6t6orologique  de  France.     (Monthly.)     Paris,  1849-91. 
Annuaire  de  I'Observatoire  de  Montsouris.     (Annually.)     Paris,  1872-91. 
Annuaire  de  I'Observatoire  Eoyal  de  Bruxelles.     (Annually.)    Bruxelles,  18.3.3-91 
BoUettino  mensuale  dell'  Osservatorio  Centrale  del  E.  Coll.  Carlo  Alberto  in  Moncalieri 

(Monthly.)     Torino,  1880-91. 
Ciel  et  Terre.     (Fortnightly.)     Bruxelles,  1881-91. 
Das  Wetter.     (Monthly.)     Magdeburg,  1884-91. 

Journal  of  the  Scottish  Meteorological  Society.     (Originally  quarterly,  now  annually. 

Edinburgh,  1863-91. 
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Symons,  G.  J. :  British  Eainfall.     (Annually.)    London,  1861-91. 
Symons's  Monthly  Meteorological  Magazine.    London,  1866-91. 
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Zeitschrift  fiir  Meteorologie.    (Monthly.)    Wien,  1866-91. 


INFLUENCE   OF   CLIMATE   ON   HEALTH 


BY 


C.  THEODOEE  WILLIAMS, 

M.A.,  M.D.  (OxoN.),  F.E.C.P. 


CLIMATE 

The  influence  of  climate  on  health  is  a  very  important  subject,  and  often 
constitutes  a  difficult  problem  for  governments  and  sanitary  authorities  to 
solve  in  regard  to  colonisation,  to  sites  of  towns,  and  to  the  disposition  of 
troops.  It  is  well  known  that  thousands  of  lives  have  been  sacrificed  to 
ignorance,  on  the  part  of  those  in  authority,  of  the  climatic  peculiarities  of 
the  regions  to  which  settlers  or  troops  have  been  sent,  while  on  the  other 
hand  military  surgeons  possessed  of  climatic  information  have  been  able  by 
due  precautions  to  preserve  armies  in  comparative  health  and  vigour,  even 
under  the  strain  of  fatigue  and  privation,  and  in  pernicious  climes. 

The  connection  of  race  and  climate  is  an  exceedingly  intimate  one,  and 
we  can  hardly  doubt  that  many  of  the  divisions  of  the  human  family  owe 
their  principal  characteristics  to  the  influence  of  different  climates  acting 
through  successive  generations ;  for  instance,  in  the  Caucasian  variety  we 
see  the  influence  of  climate  well  exemplified  in  the  contrast  between  the 
natives  of  Europe  and  of  India  ;  in  the  Mongolian  variety,  between  the 
Chinese  and  the  Esquimaux ;  or  again  in  the  difference  between  the  negroes 
of  various  parts  of  Africa,  and  lastly  we  may  even  detect  some  trace  of  this 
influence  if  we  compare  Englishmen  with  their  cousins  in  our  colonies,  and 
in  the  United  States  of  America, 

The  influence  of  climate  on  the  individual  depends  largely  on  whether  he 
be  native  or  imported  from  another  region,  and  while  in  some  localities 
emigration,  as  in  Australia,  is  attended  with  no  evil  results,  and  the  emigrat- 
ing race  even  gains  in  numbers  and  strength,  in  other  cases  it  is  not  so,  and 
the  emigrant  race  dwindles  and  disappears  under  the  new  conditions. 

In  our  great  dependency  India,  which  has  been  ruled  so  long  and  so 
judiciously  by  Great  Britain,  it  is  stated  that  the  pure  race,  if  not  inter- 
mingled with  the  native,  does  not  last  beyond  the  third  generation,  and  there 
are  other  tropical  climates,  such  as  those  of  the  West  Coast  of  Africa  and  the 
West  Indies,  that  appear  to  have  a  particularly  deleterious  and  fatal  effect 
on  the  Anglo-Saxon  race,  and  have  earned  the  name  of  the  White  Man's 
Grave.  In  these  regions  the  natives  and  especially  negroes  survive,  and 
sometimes  flourish,  but  it  is  a  mistake  to  conclude  that  they  are  miinfluenced 
by  the  climate  which  is  so  fatal  to  Europeans ;  as  a  matter  of  fact  they  do  suffer, 
but  in  other  ways.  At  the  Cape  of  Good  Hope  Hottentot  soldiers  suffered  from 
pulmonarydisorders  more  than  white  soldiers.  At  Sierra  Leone  black  regiments 
furnished  a  larger  quota  of  chest  disease  than  white  ones  in  the  ratio  of  6*4 :  4-9 
per  1,000  ^  (Boudin).  In  Jamaica  too  the  Army  j\Iedical  Eeport  for  1859  states 
that  while  not  a  single  white  soldier  was  admitted  for  tuberculous  disease,  the 
deaths  from  phthisis  among  the  negro  troops  stood  at  8*67  per  1,000  of  the 
whole  strength.  Negroes  seem  to  be  especially  prone  to  phthisis,  and  when, 
transplanted  to  a  temperate  climate,  to  develope  it  rapidly,  for  the  Army 
Medical  Eeports  also  show  that  negro  troops  when  moved  from  Sierra  Leone 
to  Gibraltar,  a  healthy  station  for  white  troops,  developed  a  phthisis  mor- 
tality of  43  per  1,000  in  place  of  6*4  at  Sierra  Leone. 

*  Walshe,  Diseases  of  Lungs.    4th  edition. 


188  HYGIENE 

In  temperate  climates  the  Anglo-Saxon  flourislies  and  spreads  in  all 
directions,  as  the  vast  and  increasing  populations  of  North  America  and 
Australia  testify. 

It  was  truly  remarked  by  the  late  Professor  Parkes  that  much  of  the 
mortality  of  Europeans  in  tropical  climates  was  due,  not  to  the  climate  alone, 
but  to  the  climate  phis  certain  other  agencies,  such  as  impure  water,  improper 
food,  bad  drainage,  and  various  kinds  of  excess,  and  that,  if  these  causes  be 
removed,  the  mortality  of  Europeans,  or  lather  of  European  troops,  in  the 
tropics  does  not  differ  so  greatly  from  the  mortality  of  troops  at  home. 

The  wonderful  improvement  in  the  health  of  troops  in  India  and  tropical 
countries  has  doubtless  been  due  to  a  more  complete  enforcement  of  military 
hygiene.  However,  after  making  fair  deduction  for  the  effect  of  errors  of 
life,  there  remains  a  certain  proportion  of  disease,  by  no  means  a  small  one, 
occurring  among  persons  of  well-regulated  life,  which  can  only  be  attributed 
to  the  effects  of  chmate.  Before  entering  more  fully  on  this  subject,  we  will 
consider  the  various  elements  of  climate  and  the  influence  that  each  indi- 
vidually exercises  on  the  human  body  ;  and  then  we  shall  be  in  a  better  posi- 
tion to  determine  the  exact  part  that  climate  plays  in  the  causation  of  disease. 

Climate  is  derived  from  the  Greek  KXt/xa  (kAiVw,  I  bend),  a  slope,  signifying 
the  curvature  of  the  earth  from  the  equator  to  the  pole,  and  indicating' 
various  qualities  of  the  atmosphere  which  surrounds  us,  such  as  its  density, 
its  temperature  and  sunlight,  its  moisture  and  rainfall,  its  winds  and  elec- 
tricity, and  all  the  factors  which  more  or  less  influence  the  human  frame. 


TEMPEKATUEE 

The  human  body  appears  capable  of  enduring  great  extremes  of  tempera- 
ture, and  of  maintaining  its  standard  of  98°  to  99°  F.  under  the  most  oppo- 
site climatic  conditions. 

It  has  been  shown  that  inhabitants  of  temperate  climates  like  Great 
Britain  can  endure  both  extremes  of  cold  and  heat  without  danger  if  they 
adopt  certain  precautions,  and  provided  the  atmosphere  be  still  and  dry. 

The  degree  of  cold  which  Arctic  voyagers  have  sustained  without  injury  is 
very  astonishing.  Captain  Parry  noted  the  thermometer  as  low  as  —  55°  F. 
or  87°  below  the  freezing  point,  Sir  John  Franklin  at  —  58°  F.  or  90°  below 
the  fi-eezing  point,  and  Sir  George  Back  at  —  70°  F.  or  102°  below  the 
freezing  point. 

Sir  John  Eichardson  ^  states  that  in  his  last  Arctic  expedition  he  was 
accustomed  to  go  from  his  sitting-room  at  a  temperature  of  50°  F.  to  his 
magnetic  observatory  at  a  short  distance  from  it,  without  feeling  it  necessary 
even  to  put  on  a  great  coat,  though  the  temperature  of  the  external  air  was 
—  50°,  and  the  difference  between  the  two  atmospheres  100°  F.  He  attributed 
this  absence  from  chilling  influence  to  the  dryness  and  stillness  of  the  air. 
The  writer,  when  visiting  the  Engadine  in  the  winter,  has  often  exposed 
himself  to  night  air,  when  the  thermometer  was  —  4°  F.,  without  catching 
cold,  and  both  at  Davos  and  St.  Moritz  it  is  the  custom  for  pulmonary  invalids 
to  sleep  with  open  windows  all  through  the  winter,  apparently  with  impunity 
and  even  benefit,  though  in  the  winter  the  night  minimum  is  sometimes 
below  —  11°  F.     This  would  be  impossible  if  there  were  much  wind. 

If  the  exposure  to  cold  be  prolonged,  and  the  circulation  and  thermogenic 
powers  cannot  be  maintained,  the  blood-vessels,  and  specially  the  smaller 
arteries  and  capillaries,  become  contracted,  and  no  longer  permit  the  passage 

'  Carpenter's  Human  Physiology.    4tli  edition,  p.  431. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  189 

of  blood-corpuscles,  and  thus  all  physiological  and  chemical  changes  are 
arrested.  Various  parts,  especially  the  extremities,  become  starved,  and  hence 
death  of  these  parts  takes  place  by  frost-bite  and  gangrene,  which  show  them- 
selves generally  in  the  toes  and  fingers.  Prolonged  exposure  to  extreme  cold 
gives  rise  to  an  overpowering  sense  of  lassitude  and  languor,  the  sensibiHty 
becomes  lowered,  the  individual  loses  power  of  reaction  and  sinks  to  sleep, 
often  to  rise  no  more,  as  is  sometimes  witnessed  in  long  journeys  through 
the  snow,  the  form  of  death  being  generally  coma.  In  other  cases  the  brain 
becomes  excited  and  the  patient  manifests  delirium,  incoherence  and  thick- 
ness of  speech,  the  symptoms  resembling  those  of  intoxication.  Death  may 
occur  from  syncope  or  asphyxia,  though  this  is  less  frequent  than  by  coma. 

The  influence  of  heat  on  the  human  body,  whether  it  be  solar  or  arti- 
ficial, does  not,  as  a  rule,  cause  any  great  rise  in  the  body  temperature,  pro- 
vided perspiration  be  free  and  abundant,  which  in  old  residents  in  the  tropics 
is  generally  the  case.  The  balancing  power  of  the  human  economy  over  its 
temperature,  through  its  secretions,  is  very  wonderful,  for  Blagden  and  For- 
dyce  bore  a  temperature  of  260°  F.  in  an  oven  with  only  the  small  rise  of 
2^°  F.,  as  long  as  the  air  was  dry  and  the  perspiration  free  ;  but  if  the  air 
became  moist  and  evaporation  was  hindered,  the  temperature  of  the  body  rose 
8°F. 

The  effects  of  the  direct  sun's  rays  will  be  considered  later,  but  various 
interesting  experiments  have  been  made  on  the  effect  of  heat  in  shade.  Dr. 
Becher  determined  his  own  temperature  in  a  very  useful  way  during  a  voyage 
from  the  Cape  to  India,  and  found  that  the  body  heat  increased  in  the  pro- 
portion '05°  F.  for  every  increase  of  1°  F.  in  the  air.  Eattray,  in  his  own 
case,  found  a  decided  increase  varying  from  -2°  to  1°*2  F.,the  maximum  being 
generally  attained  in  the  afternoon. 

The  effects  of  the  direct  sun's  rays  on  the  human  body  are,  when  not  too 
powerful,  highly  beneficial,  and  as  we  can  see  in  the  vegetable  kingdom  the 
etiolated  plant  craning  its  long  slender  stalk,  and  spreading  its  leaves  to 
catch  the  welcome  sunshine,  and,  when  this  is  reached,  exchanging  for 
transparent  stems  and  absence  of  colour  sturdy  growth  and  an  abundance  of 
chlorophyll,  so  we  witness  the  power  of  the  sun's  rays  in  the  contrast  between 
the  pallid  faces  and  complexions  of  dwellers  in  large  cities,  and  the  brown 
tint  and  ruddy  hue  and  vigorous  appearance  of  the  native  of  the  country  or 
seaside.  Though  the  intimate  chemical  and  physiological  effects  of  sunshine 
on  the  human  economy  may  be  as  yet  unknown  to  us,  we  recognise  its 
healthful  influence  in  promoting  cell  changes,  in  quickening  caj)illary  circu- 
lation, in  stimulating  gland  secretion,  and  fostering  growth  and  develop- 
ment. How  different  to  the  sensations  is  the  atmosphere  of  a  room  where 
the  sun  never  shines  to  that  of  one  with  a  southern  exposure,  where  the 
mote-laden  sunbeams  radiate  into  every  corner  and  remove  the  dank  chill 
feeling  so  generally  present  in  sunless  chambers,  about  which  the  old  Italian 
proverb  is  only  too  true,  that  '  where  the  sun  does  not  enter,  the  physician, 
will.'     Well  has  Mrs.  Hemans  said  : 

Thou  art  no  loiterer  in  monarcli's  hall, 

A  gift  thou  art,  and  a  joy  to  all. 

A  bearer  of  hope  by  land  and  sea, 

Sunbeam,  what  gift  hath  the  world  like  thee  ? 

The  effect  of  heat  on  the  lungs  is  to  diminish  the  number  of  respirations, 
as  Eattray  showed  in  persons  passing  from  a  cold  to  a  hot  chmate ;  there  was 
a  reduction  from  16'5  respirations  (in  England)  to  13'74,  and  even  to  12*74 
in  the  tropics,  accompanied,  however,  by  a  sHght  spirometric  increase,  not 


190  HYGIENE 

enough,  however,  to  compensate  for  the  diminished  number  of  respirations, 
and  so  the  respiratory  function  is  considerably  reduced,  the  reduction 
amoimting  to  at  least  18-43  per  cent.,  or,  as  Dr.  Parkes  '  puts  it,  '  If  10 
omicesof  carbon  are  expired  in  the  temperate  zone,  only  8-157  ounces  would 
be  expired  in  the  tropics.' 

There  is  also  a  diminution  in  the  water  exhaled.  The  observations  of  Parkes 
and  of  Francis  that  the  lungs  of  Europeans  in  India  are  hghter  after  death 
than  the  European  standard,  confirm  the  explajiation  given  by  Kattray  of 
the  slight  spirometric  increase,  compared  with  the  lessened  number  of  inspi- 
rations, viz.  that  in  the  tropics  there  is  a  larger  proportion  of  air  and  a 
lessened  one  of  blood  in  the  lungs.  Observations  show  that  the  heart's 
action  is  not  perceptibly  quickened  in  the  tropics,  and  that  the  pulse  is  not 
faster  than  m  temperate  regions.  The  digestive  powers  are  lessened,  and  the 
craving  for  animal  food  diminished,  and  there  is  ample  evidence  of  the  liver 
being  first  congested,  and  then  undergoing  various  indurative  changes  con- 
sequent on  active  or  passive  congestion  of  an  organ.  The  skin  is  stimulated 
to  largely  increased  action,  and  there  is  an  increase  of  excretion  estimated  at 
24  per  cent.  The  urine  is  diminished  in  quantity  and  the  amount  of  urea 
lessened,  possibly  from  less  animal  food  being  consumed.  The  nervous 
system  is  depressed,  and  specially  so  if  great  humidity  be  combined  with 
great  heat.  Great  heat  is  well  borne  by  the  system  if  the  body  temperature 
is  kept  down  by  abundant  perspiration,  and  if  the  hot  season  be  not  of  long 
duration,  but  protracted  residence  in  a  region  of  great  heat  appears  to  exer- 
cise a  depressing  influence,  lessening  the  nervous  activity  and  impairing  the 
great  functions  of  digestion  and  respiration  and  sanguification,  and  the 
power  of  forming  new  and  healthy  tissue.  The  tint  of  the  skin  and  con- 
junctivae in  Europeans  long  resident  in  the  tropics,  and  their  appearance  of 
premature  age,  all  go  to  confirm  this  conclusion. 

HUMIDITY 

There  are  few  climatic  factors  which  influence  our  sensations  more 
strongly  than  humidity.  After  several  hot  days,  or  after  a  long  succession 
of  east  winds,  a  fall  of  rain  is  followed  by  a  pleasant  refreshing  condition  of 
the  atmosphere,  which  we  all  appreciate.  On  the  other  hand,  excessive 
atmospheric  humidity  prevents  free  evaporation  from  the  skin  though  it 
often  materially  assists  expectoration,  and  is  therefore  useful  in  many  cases 
of  bronchitis.  The  effect  of  rain  on  the  circulation  may  be  illustrated  by  the 
following  :  A  consumptive  male  patient  of  mine  was  trekking  in  the  Kala 
Hari  Desert  in  the  Cape  Colony  and  apparently  flourishing  in  the  open-air  life. 
The  climate  was  exceedingly  dry,  a  difference  of  25°  P.  between  the  wet  and 
dry  bulb  being  recorded.  Heavy  rain  afterwards  fell,  the  satm-ation  point 
was  reached,  and  the  patient  immediately  had  a  severe  attack  of  haemoptysis. 
The  presence  of  a  large  amount  of  moisture  in  the  air,  while  it  promotes 
expectoration,  rather  favours  the  continuance  of  coryza  and  catarrh.  The 
combination  of  moisture  and  heat,  as  is  seen  in  the  scirocco  wind,  is  felt 
oppressive  by  most  people,  but  it  is  doubtful  if  the  combination  of  cold  and 
moisture  be  not  more  harmful. 

'  From  the  experiments  of  Lehmann  on  pigeons  and  rabbits  it  appears 
that  more  carbonic  acid  is  exhaled  from  the  lungs  in  a  very  moist  than  in  a 
very  dry  atmosphere. 

'  The  spread  of  certain  diseases  is  supposed  to  be  intimately  related  to 
humidity  of  air.     Malarious  diseases,  it  is  said,  never  attain  their  fuUest 

'  Practical  Hygiene.    4th  edition,  p.  402. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  191 

epidemic  spread  unless  the  humidity  approaches  saturation.  Plague  and 
small-pox  are  both  checked  by  a  very  dry  atmosphere.  The  cessation  of 
bubo  plague  in  Upper  Egypt,  after  St.  John's  Day,  has  been  considered  to 
be  more  owing  to  the  dryness  than  to  the  heat  of  the  air. 

'  In  the  dry  Harmattan  wind,  on  the  West  Coast  of  Africa,  small-pox  can- 
not be  inoculated  ;  and  it  is  well  known  with  what  difficulty  cow-pox  is  kept 
up  in  very  dry  seasons  in  India.  Yellow  fever,  on  the  other  hand,  seems 
independent  of  moisture,  or  will,  at  any  rate,  prevail  m  a  dry  air.'  ^ 

EAINFALL 

The  precipitation  of  atmospheric  moisture  in  the  form  of  rain  may,  if  not 
excessive,  exercise  a  beneficial  influence  on  health,  as,  besides  reducing  the 
amount  of  moisture  in  the  atmosphere,  it  sweeps  away  various  impurities 
arising  from  the  presence  of  man  and  animals,  which  would  otherwise 
accumulate,  and  thus  rainfall  considerably  promotes  the  health  of  the  com- 
munity. The  amount  of  rainfall  differs  in  different  localities  enormously, 
from  almost  nothing  in  the  Sahara  Desert  to  493  inches  at  Cherraponji  ^ 
in  Assam,  and  its  precipitation  seems  to  be  determined,  according  to  Mr. 
Scott,  in  one  of  three  ways  : — 

First,  by  the  ascent  of  a  current  of  damp  air  which,  losing  heat  in 
ascending,  is  unable  to  hold  as  much  moisture  in  suspension  as  formerly. 

Second,  the  contact  of  warm  and  damp  air  with  the  colder  surface  of  the 
ground,  as  in  the  case  of  the  western  coasts  of  Great  Britain  and  Ireland  in 
winter,  where  the  land  is  colder  than  the  sea  surface. 

Third,  the  mixture  of  hot  and  cold  masses  of  air,  of  which  the  influence 
in  promoting  rainfall  is  not  very  considerable. 

Examples  of  the  first  are  to  be  seen  where  a  Avarm  moist  wind  is  diverted 
upwards  by  an  intervening  mountain  range  ;  the  current  is  rapidly  cooled 
in  ascending  and  deposits  its  moisture  in  the  form  of  rain.  This  is  still 
more  marked  if  the  wind  comes  from  seaward,  and  in  this  way  the  S.E, 
trade  becomes  a  rain-bringer  to  the  mountains  of  Eastern  Brazil  and  the 
eastern  slopes  of  the  Andes. 

Owing  to  the  prevalence  of  easterly  winds  in  low  latitudes,  the  lee  sides 
of  tropical  mountain  ranges  are  often,  according  to  Wojeikof,  better  wooded 
and  watered  than  the  western,  whereas  in  the  temperate  zone  the  reverse  is 
the  case,  and  it  is  the  western  slopes  of  mountain  ranges  which  are  the  best 
clothed  with  vegetation  and  verdure. 

Where  trade  winds  blow,  there  is  little  or  no  rain  unless  they  blow  on  to 
a  mountainous  coast,  and  with  the  periodic  shifting  of  the  trade  wind  areas 
the  dry  areas  shift  likewise,  but  the  descent  of  the  trade  wind  brings  abundant 
rain,  and  when  the  sun  is  lowest— i.e.  in  winter.  This  season  of  winter 
rain  occurs  in  the  sub-tropical  region,  extending  from  latitudes  30°  to  40°  in 
both  hemispheres,  embracing  countries  bordering  the  Mediterranean,  with 
Asia  Minor  and  the  western  part  of  Persia  and  Oregon  and  CaHfornia  in 
North  America,  as  well  as  in  the  southern  hemisphere,  the  Cape  Colony, 
South- West  AustraHa,  and  the  northern  island  of  New  Zealand.  Exceptions 
to  this  rule  are  certain  districts  where  summer  rains  prevail  instead  of 
winter— as  the  Eastern  States  of  the  Union,  the  Argentine  Piepublic,  China, 
and  Natal,  which  benefit  largely  in  an  agricultural  point  of  view  from  rain- 
fall when  most  needed,  whereas  the  other  countries  are  liable  to  summer 

1  Parkes's  Practical  Hygiene. 

2  Eliot,  in  the  Quarterly  Joimial  of  the  Meteorological  Society,  1882,  states  40  inches 
fell  in  one  day  at  this  place. 


192  HYGIENE 

drouglits.  North  of  the  sub-tropical  region  is  the  region  of  rain  at  all 
seasons,  to  which  Great  Britain  and  Ireland  belong,  the  rainfall  depending 
on  the  somewhat  irregular  succession  of  barometrical  depressions  and  anti- 
cyclones which  are  constantly  mo%'hig  over  the  earth's  surface  in  the.  tem- 
perate zone.  The  rule  about  this  region  is  that  the  western  coasts  of  the 
continents  have  autumn  rains  gradually  passing  into  summer  rains  as  we 
advance  into  the  interior  of  the  country.  According  to  Dr.  Haian,  in  Europe 
the  Alps  divide  the  region  of  summer  rains  from  that  of  the  autumn  rains  of 
Southern  Europe.  In  North-West  France  24  per  cent,  of  the  annual  fall 
occurs  in  summer,  and  in  Central  Prussia  38  per  cent.  In  these  islands  the 
wettest  month  on  the  west  coast  is  January,  and  the  second  wettest  is 
October,  but  the  difierence  between  the  months  is  by  no  means  great,  and 
the  London  monthly  rainfall,  as  calculated  by  Mr.  Scott  and  Mr.  Dines 
from  observations  of  sixty  years,  gives  October  as  the  wettest  month,  but 
shows  the  difference  between  this  and  February,  the  driest  one,  to  be  only 
2-74  inches  against  1'50  inches.  The  annual  rainfall  in  different  parts  of 
Great  Britain  varies  greatly,  being  on  the  east  coast  18  to  23  inches,  but  on 
the  west  from  30  to  130  inches  ;  the  largest  amount  of  rainfall  in  one  day  regis- 
tered in  Great  Britain  was  5  inches,  which  fell  in  Monmouthshire  in  twenty- 
four  hours  on  July  14,  1875. 

The  regions  of  the  globe  where  most  rain  falls  are  certain  districts  in  the 
equatorial  regions  of  calms,  and  localities  where  damp  winds  meet  the  moun- 
tain ranges  and  are  thus  diverted  upwards ;  on  the  leeward  side  of  these 
ranges  there  is  usually  a  dry  tract.  Examples  of  localities  with  large  rainfalls 
are  the  Khasia  Hills  in  Assam,  with  Cherraponji ;  the  Western  Ghauts,  with 
Mahabuleshwur,  the  Western  coasts  of  the  British  Isles,  of  Norway  and 
North-West  America  or  Southern  Chili,  and  of  New  Zealand  with  Hokitika. 

On  the  other  hand,  the  driest  regions  in  the  world  are  those  stretching 
eastward  from  the  Great  Sahara  Desert  through  Arabia  to  Persia ;  the 
Great  Salt  Lake  region  in  North  America  ;  the  interior  of  Australia  and  the 
Desert  of  Gobi  in  Chinese  Tartary,  and  the  rainless  tract  of  Peru  and  Chili 
between  the  Andes  and  the  sea.  These  two  last  owe  their  dryness  to  their 
being  leeward  of  mountains  which  have  caused  the  precipitation  of  any 
moisture  contained  in  winds  passing  over  them. 

Elevation  has  been  sliOAvn  to  exercise  some  influence  over  rainfall,  and 
the  amount  of  rain  collected  increases  with  the  height  above  the  sea,  but  it 
has  been  demonstrated  that  in  India  the  maximum  fall  occurs  at  an  eleva- 
tion of  about  4,000  feet,  being  the  level  at  which  the  south-west  monsoon 
is  cooled  just  below  its  dew  point.  Mahabuleshwur  and  Cherraponji  are  about 
that  level ;  above,  the  air  appears  too  cold  to  contain  much  vapour. 

Hann  finds  that  in  the  Austrian  Alps  and  in  parts  of  Central  Europe, 
the  maximum  of  rainfall  in  winter  occurs  at  an  elevation  of  3,000  to  4,000 
feet,  but  that  in  summer  this  level  is  above  the  highest  peaks. 

In  the  British  Isles  there  appears  to  be  no  rule  of  increase  of  rainfall 
with  elevation  :  and  on  the  western  coasts,  especially  the  Lake  District  and 
that  of  Glencoe  in  Scotland,  which  appear  to  be  the  wettest  regions,  more 
eeems  to  depend  on  the  trend  of  the  valleys  or  on  their  confluence,  than  on 
their  elevation. 

BAROMETBIC   PEESSURE 

The  ordinary  varieties  of  barometric  pressure  at  the  sea-level  have  not 
been  shown  to  mfluence  health  considerably,  except  when  combined  with 
other  meteorological  elements  such  as  those  of  temperature  and  moisture, 


INFLUENCE   OF  CLIMATE   ON  HEALTH  193 

but  when  the  barometric  pressure  is  lessened  to  the  extent  of  several  inches. 
as  in  balloon  voyages,  or  in  mountain  ascents,  or  when  it  is  largely  increased 
as  in  descents  in  diving-bells,  or  pneumatic  tubes  in  use  for  the  construction 
of  piers  and  bridges,  such  change  exercises  considerable  influence  on  the 
circulatory  and  respiratory  system  of  man. 

Diminution  of  barometric  pressure  is  accompanied  by  decrease  of  mois- 
ture and  by  increased  power  of  the  sun's  rays  from  the  greater  diathermancy 
of  the  atmosphere — i.e.  the  increased  facility  by  which  the  sun's  rays  are 
transmitted  through  attenuated  air.  According  to  Dr.  Denison  this  causes 
an  increased  difference  between  the  sun  and  shade  temperatures  of  1°  F.  for 
every  rise  of  235  feet,  and  consequently  the  extremes  of  temperature  are 
much  greater  than  at  sea-level,  and  the  atmosphere  is  drier  and  more 
aseptic,  being  shown,  in  some  instances,  to  be  devoid  of  germs.  The  great 
heat  on  mountain  sides  covered  with  snow  when  the  sun  shines  is  explained 
by  the  before-mentioned  diathermancy. 

Let  us  now  first  consider  the  effect  of  diminished  barometric  pressure 
due  to  rarefaction  of  the  atmosphere  as  we  ascend  mountains.  The  baro- 
meter which  stands  at  30  inches  at  sea-level  with  appropriate  corrections 
gives  at  5,000  feet  a  reading  of  25  inches  and  one  of  20'5  at  10,000  feet,  thus 
showing  a  fall  of  5  and  of  9'5  inches  respectively,  and  these  are  the  degrees 
of  diminution  of  pressure  which  are  made  use  of  for  purposes  of  medical 
treatment. 

Nevertheless  in  the  Andes  people  live  and  flourish  at  far  greater  heights. 
La  Paz,  the  capital  of  Bolivia,  a  city  of  from  70,000  to  80,000  inhabitants, 
is  situated  13,500  feet  above  sea-level,  showing  that  man  is  capable  of  sus- 
taining without  injury  considerable  diminution  of  barometric  pressure. 

The  effect  of  extreme  and  sudden  diminution  of  pressure  was  seen  during 
Glaisher  and  Coxwell's  balloon  ascent,  when  the  reduction  to  9|  inches  pres- 
sure showed  an  elevation  of  29,000  feet,  when  Mr.  Glaisher  lost  consciousness 
though  the  balloon  mounted  yet  higher,  and  Mr.  Coxwell  believed  he  noted  a 
reading  of  only  7  inches  before  the  descent  commenced,  which  would  indicate 
a  height  of  37,000  feet !  However,  we  cannot  tell  for  certain  whether  Mr. 
Glaisher's  loss  of  consciousness  was  due  to  the  cold  or  to  the  altitude,  but 
probably  from  the  presence  of  lividity  it  was  due  to  the  latter.  Li  M. 
Tissandier's  ascent  with  MM.  Sivel  and  Croce-Spinelli  in  the  '  Zenith  '  from 
Paris  in  1875,  a  height  of  8,600  metres  (28,155  feet)  was  reached  too  rapidly, 
followed  by  a  descent  between  6,000  and  7,000  feet,  and  then  a  second  ascent  ta 
nearly  the  same  height,  the  result  being  that  all  the  observers  were  overcome 
and  lost  all  power  of  movement  and  consciousness,  and  two  died  apparently 
from  want  of  oxygen,  presenting  cyanosed  countenances,  with  eyes  sunk,  and 
mouths  open  and  full  of  clotted  blood,  M.  Tissandier  reaching  the  ground  in 
an  almost  unconscious  condition.  He  graphically  describes  the  gradual  loss 
of  power  in  the  higher  regions,  which  precluded  his  using  the  oxygen  inhala- 
tions with  which  he  was  furnished.  The  fatal  results  were  attributed  not  to 
the  altitude  but  to  the  rapidity  of  the  ascent,  before  the  lungs  could  accustom 
themselves  to  the  altitude — to  the  long  exposure  at  a  great  height,  and  to 
the  inabnity  of  the  aeronauts  to  inhale  the  oxygen  gas  from  sheer  loss  of 
power,  precluding  them  even  grasping  the  tubes  of  the  inhalers. 

The  physiological  effects  of  diminished  barometric  pressure  indicate  that 
for  elevations  not  exceeding  6,000  feet  the  pulse-rate  for  natives  does  not 
differ  from  the  normal  standard,  and  for  strangers  there  is  at  first  quickening 
of  the  normal  rate  and  a  diminution  at  a  later  date,  due  to  a  more  powerful 
cardiac  impulse  and  a  stronger  vascular  system. 

With  regard  to  higher  altitudes  than  6,000  ft.,  the  evidence  on  the  whole 
VOL.  I.  o 


104  HYGIENE 

points  to  a  decided  increase  in  the  pulse-rate,  for  Zapater  at  Janja  in  the 
Andes  (10,000  feet)  and  Kellet  at  Landour  in  the  Himalayas  (7,000  feet) 
found  the  natives  with  increased  pulse-rate.  Denison,  of  Denver  in  the 
Eocky  Mountains,  lays  down  a  law  that  the  pulse  increases  2  per  cent,  for 
every  1,000  feet  ascended.  The  influence  of  diminished  barometric  pressure 
on  the  respiration  is  more  marked.  The  first  effect  is  an  increase  in  the 
number  of  respirations,  and  visitors  to  high  altitudes  often  complain  of  short- 
ness of  breath,  but  after  some  weeks'  residence  the  lungs  becoming  expanded 
and  the  thorax  widened,  the  vital  capacity,  as  shown  by  the  spirometer, 
increases,  and  the  respiration  rate  diminishes  and  returns  to  the  normal 
standard  or  even  becomes  slower,  the  respirations  being  deeper.  This  would 
apply  to  dwellers  at  moderate  altitudes,  say  under  G,000  feet  above  sea-level, 
but  in  natives  of  higher  altitudes  the  respiration  rate  has  been  noted  to  be 
higher  than  normal. 

The  tanning  of  ihe  skin,  so  marked  in  high-lying  places,  is  undoubtedly 
due  to  the  greater  power  of  the  solar  rays  from  the  increased  diathermancy. 
Another  well-marked  effect  of  diminished  barometric  pressure  is  the  soroche, 
•or  puna,  or  mal  des  montagnes,  which  attacks  people  generally  at  an  altitude 
of  12,000  feet,  and  upwards,  and  appears  principally  to  affect  the  nervous 
system.  It  prevails  most  markedly  in  the  Andes,  and  affects  human  beings 
and  animals  on  ascending  from  the  sea  coast  to  the  higher  levels,  the  bulls 
for  the  bull  fights  being  included. 

Eeviewing  the  relation  of  diminished  barometric  pressure  to  health,  we 
cannot  say  that  it  is  injurious,  but  rather  the  reverse.  The  attenuation  of 
the  atmosphere  and  the  consequent  diminution  in  the  amount  of  oxygen 
contained  necessitates  deeper  and  fuller,  and  at  first  more  frequent  inspira- 
tions, and  consequently  we  get  a  larger  development  of  the  inspiratory  organs, 
and,  as  an  effect,  a  more  vigorous  heart  and  vascular  system.  Hence  the 
broad  and  deep  thorax,  with  accompanying  well-developed  muscles  of  the 
mountain  races,  such  as  is  seen  in  the  Indians  of  the  Andes,  in  the  guides  of 
ihe  Alps,  and  other  mountaineers,  who  are  renowned  for  their  vigour  and  their 
great  power  of  endurance  during  long  marches  and  expeditions.  It  is  stated 
that  the  Indians  of  the  Andes  can  walk  50  miles  a  day,  ascending  mountains 
■en  route. 

Increased  Barometeic  Pressure 

Our  knowledge  of  the  effects  of  increased  barometric  pressure  on  human 
Tseings  is  derived,  not  from  the  bottom  of  mines,  where  there  is  undoubtedly 
increase  of  barometric  pressure,  but  of  too  slight  a  degree  to  cause  any 
distinct  influence,  but  rather  from  the  results  of  the  compressed  air  used 
in  diving-bells,  diving  apparatus,  and  the  caissons  or  tubes  employed  in  the 
building  of  piers,  for  in  these  latter  men  have  worked  for  hours  at  a  time 
;at  a  pressure  of  2^  to  4^  atmospheres,  and,  when  proper  precautions  were 
observed,  apparently  without  harm. 

The  symptoms  noticed  in  descending  in  diving-bells  to  a  depth  of  30  feet 
"were  pains  in  the  ears,  noises  and  even  deafness,  a  sensation  of  tightness  as 
if  the  head  were  bound  round  with  iron,  these  symptoms  being  more 
marked  if  the  descent  was  rapid.  At  this  depth  there  was  no  change  in  the 
pulse  or  respiration. 

In  pneumatic  tubes  air  is  pumped  in  to  the  extent  of  3  or  4  atmospheres, 
and  workmen  are  thus  enabled  to  remain  at  work  on  the  foundations  of  bridges 
or  piers  below  the  level  of  the  water  for  several  consecutive  hours.  When 
precautions  in  entering  and  leaving  the  tubes  were  duly  taken,  no  marked 
symptoms  were  noted,  but  when  this  was  not  so,  ill  effects  were  observed. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  195 

In  some  works  at  Douchy,  out  of  64  workmen,  32  suffered  more  or  less,  of 
•whom  two  died.  On  the  other  hand  one,  an  asthmatic,  improved  in  breathing, 
:and  another,  a  chloro-anajmic  individual,  gained  colour.  Out  of  22  workmen 
who  commenced  labour  at  4:-15  atmospheres,  one  had  slight  haemoptysis,  eight 
experienced  muscular  pains  in  different  parts  of  the  body,  some  lasting 
several  days,  and  one,  a  man  of  40,  of  robust  appearance,  who  descended  the 
tube  only  once,  died  immediately  after  leaving  the  tube,  the  pressure  having 
loeen  reduced  to  the  normal  in  twenty  minutes. 

In  this  case  a  post-mortem  examination  showed  general  cutaneous 
emphysema,  congestion  of  lungs  of  specially  dark  tint,  the  liver,  spleen,  and 
kidneys  engorged,  and  the  heart  containing  dark  and  fluid  blood ;  nothing 
abnormal  was  noted  in  the  brain  or  meninges. 

Compressed  air  is  employed  also  in  the  apparatus  by  which  divers  carry 
■on  operations  at  depths  of  54  metres  and  less,  and  it  must  be  remembered 
that  the  conditions  are  not  quite  the  same  as  in  the  pneumatic  tubes,  owing 
to  the  additional  pressure  of  the  water  on  the  bodies  of  these  men,  which  at 
that  depth  equals  6  atmospheres.  Accidents  seem  more  common,  and  deaths 
are  far  from  rare.  It  was  calculated  that  among  the  sponge  divers  of  the 
•Grecian  Archipelago  the  mortality  was  10  per  cent.,  and  this  does  not  include 
the  minor  accidents.  They  appear  to  suffer  in  much  the  same  way  as  those 
who  work  in  pneumatic  tubes,  only  more  severely  ;  prickings,  muscular  pains, 
.and  pains  in  the  parts  are  complained  of,  the  prickings  {les  puces)  never  taking 
place  where  there  is  much  perspiration,  and  the  muscular  pains  being  most 
marked  in  the  muscles  chiefly  used  by  the  divers.  One  diver  had  epistaxis  at 
the  bottom  of  the  sea,  which  was  repeated  on  a  second  descent  and  accom- 
panied by  severe  pains  in  the  head.  The  serious  accidents  consist  of  paralysis 
of  different  kinds,  and  invariably  occur  after  the  diver  has  left  the  water.  The 
general  form  is  paraplegia,  including  paralysis  of  the  bladder  and  of  the 
sphincter  ani.  In  some  cases,  the  loss  of  power  extends  to  the  upper  extre- 
mities and  is  accompanied  by  loss  of  sensation  over  the  whole  body.  Some  of 
the  deaths  occur  immediately  after  leaving  the  water,  and  appear  to  resemble 
those  which  took  place  in  the  works  at  Douchy.  A  post-mortem  examination 
after  one  of  the  deaths  from  paralysis  showed  extravasation  of  blood  between 
the  spinal  dura  mater  and  the  arachnoid,  and  the  greater  part  of  the  spinal 
cord  itself  was  in  a  condition  of  softenmg. 

M.  Bucquoy  made  observations  on  the  circulation  of  workers  in  compressed 
air-tubes,  and  from  a  large  number  of  instances  concluded  that  in  the  first 
increase  of  pressure  in  the  tube  the  pulse  rises  about  20  beats,  and  that  some 
increase  is  maintained  during  the  whole  stay,  the  rate  falling  at  the  end  of  an 
hour  to  7  above  the  normal ;  and  M.  Gal's  observations  on  the  pulse  of  the 
Greek  divers  exactly  corresponds  with  this,  for  he  found,  as  a  rule,  an  increase 
of  from  70  to  90  beats.  M.  Bucquoy  also  found  that  the  respiratory  rate  in- 
creased temporarily,  but  that  such  increase  lasted  only  about  15  hours  after 
returning  to  ordinary  conditions.  We  must  bear  in  mind  that  both  in  pneu- 
matic tubes  and  in  diving  the  workmen  are  engaged  in  arduous  labour, 
natiTrally  involving,  even  at  ordinary  levels,  an  increase  in  the  pulse  and  re- 
spiration rate. 

On  reviewing  the  accidents  related,  it  would  appear  that  they  were  much 
more  due  to  the  reduction  of  the  high  pressures,  than  to  the  high  pressures 
themselves.  Very  few  unfavorable  symptoms  appear  to  have  been  noted  during 
high  pressure  in  the  tubes,  and  it  is  marvellous  how  well  high  pressures  were 
borne ;  but  most  of  the  accidents  occurred  either  during  rapid  reduction  of 
pressure,  or  subsequent  to  quitting  the  tubes.  In  many  instances,  pressure  of 
4-45  atmospheres  was  reduced  in  three  to  four  minutes  to  the  normal,  a  pro- 

o2 


196  HYGIENE 

ceediug  which  has  been  proved  by  experience  to  be  fraught  with  danger.  The 
symptoms  seem  principally  to  be  due  to  lesions  of  the  nervous  system,  com- 
mencing vnth.  dyspnoea,  quickening  of  the  pulse,  muscular  pains  of  more  or  less 
intensity,  and  gradually  increasing  in  severity  ;  then  come  the  different  forms 
of  paralysis,  including  loss  of  sight  and  hearing,  paraplegia,  stupor,  loss  of  con- 
sciousness, coma,  and  death.  The  divers  appear  to  suffer  more  intensely  than 
the  workmen  m  compressed  air-tubes  ;  but  among  these  also'  the  accidents 
were  almost  invariably  due  to  rapid  diminution  of  pressure. 

When,  however,  air  at  lower  pressure  is  made  use  of,  as  when  healthy  in- 
dividuals are  submitted  to  the  action  of  a  compressed  air  bath  of  10  lbs.  to 
the  square  inch  pressure,  the  results  are  different,  great  care  being  taken  to 
increase  or  reduce  pressure  gradually.  For  this  reason  a  compressed  air  bath 
is  arranged  to  last  two  hours.  During  the  first  half-hour  pressure  is  gradually 
increased,  then  maintained  at  the  full  for  an  hour,  and  the  last  half-hour  it  is 
slowly  diminished  to  the  normal.  The  first  sensations  are  noises  in  the  ears, 
a  sensation  in  the  pharynx,  reheved  by  swallowing  saliva  or  fluid,  and  some- 
times pain  in  the  membrana  tympani,  all  these  sensations  disappearing  quickly 
on  the  increase,  but  returning  on  the  reduction  of  pressure,  and  depending 
on  the  differences  in  the  density  of  the  air  on  either  side  of  the  membrana 
tympani.  The  special  senses  of  taste,  smell,  hearing,  are  said  to  be  deadened, 
the  voice  becomes  shriller,  and  whistling  is  impossible.  The  respiration 
becomes  slower,  deeper,  and  more  easy,  and  the  thorax  increases  in  circum- 
ference, apparently  from  greater  lung  capacity.  While  the  respirations  fall  in 
number  from  sixteen  or  eighteen  to  four  or  five  a  minute,  and,  as  might  be 
anticipated,  the  relation  of  inspiration  to  expiration  is  changed,  and  the  latter 
becomes  of  longer  duration  tlian  the  former.  The  pulse  becomes  slower  and 
smaller  in  volume,  but  of  increased  arterial  tension  (shown  by  sphygmographic 
tracings),  the  capillaries  are  smaller,  the  veins  less  full  of  blood.  The  amount 
of  decrease  in  the  pulse  varies  from  four  to  twenty  beats  a  minute.  All 
experiments  go  to  show  that  compressed  air  exercises  an  intropulsive  influence 
affecting  naturally  those  surfaces  most  exposed  to  it,  such  as  the  skin  and 
lungs  ;  the  blood  is  thus  driven  into  the  organs  protected  from  air  pressure, 
such  as  the  brain,  the  heart,  liver,  spleen,  and  kidneys.  The  retardation  of 
the  pulse  is  assigned  by  some  to  diminished  heart's  action,  owing  to  the  great 
obstacles  the  circulation  meets  with  in  the  superficial  vessels.  The  tempe- 
rature is  slightly  raised  in  the  mouth  "and  rectum,  but  not  in  the  axilla,  the 
urine  is  increased  in  amount,  and  there  is  more  urea  excreted  by  the  kidneys, 
and  more  carbonic  acid  from  the  lungs. 

Muscular  power  is  increased,  and  this  was  found  to  be  the  case  both  in 
the  compressed  air  bath  and  in  the  air  at  high  pressure  in  the  pneumatic 
tubes. 

WINDS 

There  is  no  question  that  the  great  aerial  movements  which  prevail  under 
the  name  of  winds  play  a  very  important  part  in  the  purifying  of  the  atmo- 
sphere, and  in  preventing  that  stagnation  of  air  which  is  favourable  to 
bacterial  growth  and  multiplication.  They  thus  are  important  agents  in  the 
promotion  of  health,  for,  as  the  appearance  of  a  great  epidemic  has  been 
observed  to  be  connected  with  a  very  calm  state  of  the  atmosphere,  so  the 
springing  up  of  a  strong  wind  has  often  been  the  signal  of  its  decUne  and. 
disappearance.  So  con^dnced  were  the  ancient  Greeks  of  the  beneficial 
influence  of  wind  to  combat  disease,  that  at  Girgenti  (Agrigentum),  in  Sicily, 
the  traveller  is  shown  the  artificial  opening  which  Empedocles  made  in  the 


INFLUENCE   OF  CLIMATE   ON  HEALTH  197 

rock  to  admit  the  Tramontana,  or  north  wind,  and  thus  to  dispel  the  malaria 
arising  from  the  plain  below  the  city. 

We  have  permanent  winds,  like  the  N.E.  and  S.E.  trades,  blowing 
towards  the  equator  from  the  poles  to  replace  the  ascending  heated  air  of  the 
tropics,  and  owing  their  direction  to  the  earth's  rotation,  and  we  have 
periodical  and  variable  winds  due  to  local  causes  not  always  in  action. 

The  permanent  winds,  like  the  trades  and  anti-trades,  vary  their  area  of 
prevalence  with  the  season  of  the  year,  but  there  are  other  winds  which  are, 
strictly  speaking,  seasonal ;  as,  for  instance,  the  N.E.  and  S.W.  monsoons, 
which  prevail  in  India  and  China  during  certain  times  of  the  year,  and 
have  been  fitly  named  by  Blanford  the  winter  and  summer  monsoons 
respectively.  The  N.E.  monsoon  corresponds  to  the  N.E.  trade,  and  would 
be  constant,  were  it  not  for  the  special  distribution  of  land  and  water  in  the 
eastern  hemisphere.  According  to  Fayrer,'  the  monsoons  are  caused  in  the 
following  manner  :  '  About  the  commencement  of  April,  when  the  whole 
surface  of  the  continent  of  India  becomes  hotter  than  the  sea,  the  rarefied 
air  rises,  and  is  replaced  by  the  comparatively  cooler  currents,  laden  with 
moisture  taken  up  by  evaporation  from  the  Indian  Ocean  extending  from 
Africa  to  Malacca.  This  is  the  S.W.  monsoon,  which,  rising  to  higher  regions, 
or  being  intercepted  by  the  mountain  ranges,  condenses  its  moisture  in  rain 
on  the  Western  Ghats  and  on  the  coast  of  Aracan.  Following  a  north- 
eastern course  it  loses  its  influence  and  its  rain  as  it  approaches  the  northern 
limit  of  the  continent.  About  October  the  winds  are  variable,  and  there  is 
a  reversal  of  the  current,  which  begins  to  blow  southward,  for  the  most  part, 
as  a  dry  current,  till  on  the  Coromandel  coast  it  brings  moisture  from  the 
Bay  of  Bengal,  which  falls  as  rain  on  the  coast  of  the  Carnatic  and  Eastern 
■Ghats,  while  some  parts  of  India  receive  a  certain  amount  of  rain  with  each 
monsoon.' 

The  S.W.  monsoon  is  accompanied  by  low  barometric  pressure  and  heavy 
rains. 

It  would  appear,  according  to  Mr.  Scott,  that  in  Western  Europe  the  most 
frequent  wind  in  winter  is  the  S.W.,  while  both  in  Eastern  Asia  and  Eastern 
South  America  it  is  the  N.W. ;  but  these  latter  regions  differ  in  this  respect, 
that  though  W.  winds  come  next  to  N.W.  in  both  cases,  in  Asia  the  S.W. 
comes  far  behind,  while  in  Eastern  North  America  it  blows  as  frequently 
as  the  west  winds.  Also,  looking  at  the  amount  of  rise  and  fall  of  tempera- 
ture caused  by  the  prevalence  of  each  wind,  compared  with  the  mean 
temperature,  we  find  the  S.W.,  the  most  frequent  wind  in  Western  Europe, 
is  the  warmest  in  Central  Europe,  raising  the  temperature  5°'6  F.,  while 
the  N.E.,  the  coldest  wind  in  Central  Europe,  lowering  the  temperature  7° 
F.,  is  in  the  west  the  least  frequent  but  one  of  the  eight  winds  ;  whereas,  on 
the  eastern  coasts  of  Asia  and  America  the  most  frequent  wind— N.W. — 
lowers  the  temperature  as  much  as  4°-5  F.,  while  the  S.  wind,  which  raises 
the  temperature  more  than  10°  F.,  is  the  rarest  of  all. 

In  Great  Britain,  according  to  Mr.  Glaisher's  Greenvrich  tables,  by  far 
the  most  prevalent  wind  for  aU  seasons  of  the  year  is  the  S.W.,  and  next,  the 
W.,  these  two  prevaihng  three  times  more  frequently  than  the  N.E.,  and  six 
times  more  so  than  the  E.  wind ;  though  probably  the  latter,  from  the  sensa- 
tions it  gives  rise  to,  makes  its  prevalence  more  felt.  The  N.E.  is  the  rarest 
wind,  and  next  in  rarity  come  the  S.E.,  the  E.,  and  the  N.,  separated  by  no 
great  intervals.  As  we  know  well,  the  W.  and  S.W.  winds  in  this  hemisphere 
are  the  result  of  the  equatorial  current  and  Gulf  Stream,  and  are  warm  and 
;bring  rain,  whereas  the  N.E.  and  E.  winds,  blowing  from  the  vast  continents^, 
*  Rainfall  and  Climate  in  India. 


198  HYGIENE 

of  Europe  and  Asia,  and  only  moistened  by  passing  the  narrow  strip  of  the 
North  Sea,  are  dry  and  cold. 

Allusion  must  be  made  to  the  ordinary  land  and  sea  breeze,  which  is  ex- 
plained by  Mr.  Blanford  ^  on  the  principles  of  general  atmospheric  circulation. 
He  holds  that  '  when  the  air  over  the  land  is  expanded,  and  raised  more  or- 
less  hke  a  bhster,  the  upper  strata  slide  oft"  towards  the  cooler  sea  and  pro- 
duce an  increment  of  pressure  at  some  distance  from  the  land.  The  air 
begins  to  flow  from  the  region  of  increased  pressure  towards  that  where  the 
air  is  rarefied,  and  the  pressure  is  in  defect ;  and  so  we  have  a  sea  breeze- 
setting  in  from  the  offing ;  not  a  wind  drawn  in  by  suction  and  working  its 
way  backwards,  as  would  be  the  case  if  the  particles  nearest  the  heated  spot 
moved  first.  At  night  the  action  is  reversed  ;  the  air  over  the  land  is  cooled 
by  radiation  and  contracts  ;  the  isobaric  surfaces  slope  towards  the  land,  and 
the  air  above  slides  down  from  the  sea,  sinking  over  the  land  and  pushing 
its  way  out  as  the  land  breeze.' 

The  valley  wind  (Thalwind)  in  the  Alps  and  other  mountain  ranges, 
which  blows  up  valleys  in  the  morning,  is  caused  by  the  air  of  the  valley  and. 
lower  regions  being  heated  after  sunrise  and  ascending  the  mountain  sides  ; 
after  sunset  this  is  replaced  by  a  wind  blowing  down  the  valley,  due  to  the 
fall  of  temperature  in  the  valley  air  from  radiation,  causing  contraction  of 
the  lower  stratum,  and  consequently  a  partial  vacuum,  which  the  downward 
current  from  the  mountains  descends  to  supply. 

There  are,  however,  certain  local  winds  of  great  influence  on  the  health 
of  the  countries  in  which  they  prevail,  which  deserve  notice. 

The  Khamseen  wind  is  a  hot,  dry  blast  from  the  desert,  laden  with  sand 
particles,  which  blows  in  Egypt  for  fifty  days  in  the  spring.  The  Harmattan 
is  another  withering  desert  wind,  blowing  over  the  Saliara  towards  the 
Guinea  Coast,  and  whose  influence  is  felt  in  the  Cape  Verde  Islands. 

The  Simoom  is  regarded  more  as  a  species  of  whirlwind  ;  it  prevails  in, 
Arabia,  and  sometimes  buries  whole  caravans  in  sand. 

The  Mediterranean  basin  and  its  shores,  from  their  greater  warmth  in: 
winter  and  spring,  are  liable  to  the  prevalence  of  winds  of  great  power,  which 
blow  principally  from  the  north.  These  are  currents  of  cool  air  from  an 
upper  stratum  rushing  in  to  supply  the  partial  vacuum  caused  by  the  heated 
air  ascending  from  the  warm  area. 

The  principal  are  the  Bise,  or  Bora,  or  N.E.  wind,  and  the  Mistral,  or 
Maestro,  a  N.W.  wind.  It  may  be  stated  with  regard  to  the  Mediterranean 
region  generally,  that  its  winds  present  this  marked  difference  from  those  of 
Great  Britain  and  Ireland,  that  whereas,  in  the  latter,  the  westerly  winds 
are  moist  and  the  easterly  are  dry  winds,  in  the  South  of  France  the  reverse 
is  the  case,  and  the  easterly  winds  are  the  moist  ones,  as  E.,  N.E.,  and  S.E.. 
(Scirocco),  while  the  westerly,  such  as  the  W.,  and  N.W.  are  remarkably 
dry  winds. 

The  N.E.  wind  is  a  cold  blast,  coming  generally  from  some  portion  of  the 
Alps  and  their  subsidiary  ranges,  and  is  most  prevalent  at  the  end  of  the 
Adriatic  under  the  name  of  the  Bora.  At  Nice  the  same  wind  is  called  the 
Bise,  and  is  cold,  coming  straight  from  the  Maritime  Alps. 

The  N.W.,  or  Mistral,  is  the  most  powerful  wind  in  the  South  of  France. 
It  appears  in  the  Ehone  Valley,  first  to  the  east  of  the  Cevennes  Eange,  and 
sweeps  down  the  valley,  carrying  destruction  to  crops,  and  penetrating  to  all 
spots  on  the  Eiviera  unprotected  by  mountain  ranges,  and  making  itself 
much  felt  at  Marseilles  and  Toulon. 

It  blows   over   the   passes    in   the    Maritime   Alps,   oversetting   carts,, 
•  Indian  Meteorologist's  Vade  Mecum. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  V3'J 

carriages,  and  heavy  diligences  en  route  ;  and  lashing  the  dark  blue  waters 
of  the  Mediterranean  into  foam  and  billows,  causing  storms  in  the  Gulf  of 
Lyons.  With  all  this  it  is  not  a  cold  wind,  but  a  dry  one,  and  the  barren- 
ness of  the  mountains  of  Provence  is  attributed  to  its  influence.  During 
its  prevalence  it  is  not  rare  for  the  wet  and  dry  bulb  thermometer  to  indicate 
a  difference  of  10°  between  the  bulbs,  and  it  is  always  a  harbinger  of  fine 
weather.  The  first  effect  of  this  wind  on  visitors  is  agreeable,  from  its  cool- 
ness, but  from  its  dryness  it  soon  causes  unpleasant  sensations  in  the  nose 
and  mouth,  and  often  pains  in  the  limbs.  In  consumptives  its  appearance 
has  been  sometimes  followed  by  an  attack  of  haemoptysis. 

The  S.E.,  or  Scirocco,  is  a  wind  of  the  very  opposite  kind  to  the  mistral,  as 
it  is  warm,  and  in  Italy  and  the  South  of  France  moist,  and  generally  preludes 
rain,  though  in  Syria  it  is  regarded  as  a  dry  wind.  It  is  supposed  to  arise 
in  the  Sahara  Desert,  and  to  gather  moisture  in  crossing  the  Mediterranean, 
and  certainly  its  character  in  the  different  countries  over  which  it  blows 
would  support  this,  as  in  Malta  and  Sicily  it  is  hot  and  very  relaxing,  while 
in  Corsica  it  is  less  so,  but  when  it  reaches  the  Genoese  Eiviera  it  has  lost 
some  of  its  languor-giving  qualities,  and  is  very  moist,  but  not  very  warm. 


ATMOSPHEEIC   ELECTEICITY. 

Though  midoubtedly  the  electrical  condition  of  the  atmosphere  exercises 
considerable  influence  on  the  human  frame,  it  is  difficult  to  measure  its  effects 
accurately,  and  to  separate  this  influence  from  that  of  other  meteorological 
factors.  The  crackling  of  hair,  and  its  tendency  to  stand  on  end  after 
combing,  during  frosty  weather,  is  an  example  of  electric  discharge  from  the 
human  body,  and  sparks  have  been  seen  to  issue  under  certain  circumstances. 

The  illumination  of  the  head  of  the  *  parvus  lulus  '  mentioned  in  the 
first  book  of  Virgil's  '  ^neid  '  has  been  assigned  to  atmospheric  electricity. 

According  to  Quetelet's  observations  at  Brussels,'  the  diurnal  march  of 
electricity  exhibits  two  maxima,  viz.  at  8  a.m.  and  9  p.m.  in  summer,  and 
at  10  A.M.  and  6  p.m.  in  winter,  the  day  minimum  being  3  p.m.  in  summer, 
and  1  P.M.  in  winter,  and  the  variations  in  electricity  precede  by  about  an  hour 
those  of  the  barometric  range.  The  maxima  occur  at  the  periods  of  most 
rapid  change  of  temperature,  and  the  day  minimum  corresponds  with  the 
period  of  maximum  temperature  and  minimum  humidity.  It  appears  that 
the  electrical  phenomena  in  Brussels  at  any  rate  are  thirteen  times  more 
active  in  January  than  in  July.  This  coincidence  of  the  electric  maximum 
with  the  periods  of  most  rapid  change  of  temperature  may  afford  some  ex- 
planation of  the  extraordinary  degree  to  which  some  individuals  are  affected 
by  change  of  weather,  but  what  would  be  most  interesting  to  know,  is  the 
extent  to  which  the  prevalence  of  certain  winds  influence  the  amount  of 
electricity.  '  It  is  generally  stated  that  the  potential  of  the  ak  is  positive,  but 
there  are  exceptions,  possibly  depending  on  the  prevailing  wind.  Clouds  are 
electrified,  either  positively  or  negatively,  and  of  course  the  sign  of  the 
electricity  recorded  close  to  the  ground  will  be  affected  accordingly.' 

It  is  not  uncommon  for  persons  standing  on  the  top  of  a  mountain  or 
cliff,  during  a  thunderstorm,  to  become  the  conductors  of  electricity  passing 
from  the  earth  to  the  cloud,  and  vice  versa.  The  writer  once  experienced 
this  at  the  summit  of  the  Piz  d'Arzinol  in  the  Val  d'Herens  in  Switzerland, 
where  a  thundercloud  enveloped  himself  and  his  two  companions,  and  all 
three  felt  a  distinct  buzzing  m  their  hair,  like  that  of  insects,  which  ceased 

'  Scott,  Elementary  Meteorology. 


'iOO  HYGIENE 

immediately  when  a  descent  was  made  from  the  summit.  Mr,  F.  C.  Smith 
and  his  friends  noted  on  the  top  of  the  Piz  Languard  a  crackhng  sound,  and 
on  raising  their  alpenstocks  points  upwards  felt  the  electrical  currents 
passing  through  their  bodies,  and  heard  the  crackling  as  these  passed  into 
the  sticks.  They  also  experienced  the  sensation  strongly  in  their  temples 
and  their  finger  ends.  Far  more  serious  than  these  phenomena  are  the 
accidents  from  lightning  which  occur  frequently  and  are  occasionally  fatal. 

Accordmg  to  M.  Boudin  ^  and  others,  the  principal  lesions  are  loss  of 
consciousness  combined  with  paralysis,  more  commonly  affecting  the  lower 
limbs  than  the  upper,  burns,  skin  eruptions,  often  eczema  or  urticaria,  loss  of 
hair  in  various  parts  of  the  body,  wounds,  haemorrhage  from  the  mouth, 
nose,  or  ears,  loss  of  sight,  smell,  hearing,  and  taste,  though  exaltation  of 
these  senses  has  been  known  to  occur. 

If  the  individual  struck  does  not  die  immediately  from  the  efi:ects,  he  may 
be  expected  to  recover.  The  lightning  generally,  as  might  be  anticipated, 
takes  the  line  of  any  metal  about  the  person.  It  is  generally  the  watch- 
chain  or  watch  which  is  shivered  or  melted,  and  next  it  is  attracted  by  the 
nails  in  the  boots,  thus  reaching  the  earth.  A  most  interesting  case  of 
lightning  injury  was  shown  at  the  Clinical  Society  ^  by  Sir  James  Paget  from 
the  practice  of  Dr.  Wilks  of  Ashford,  where  a  labourer,  when  struck  by 
lightning,  had  his  clothes  stripped  off  him  by  the  current,  leaving  him  stark 
naked,  and  severely  burnt  in  various  parts  of  his  body.  The  clothing  in 
contact  with  metal,  such  as  the  watch  or  watch  chain  and  nails  in  boots, 
was  completely  charred.  The  fact  of  the  clothing  being  wet,  and  therefore  a 
good  conductor,  doubtless  in  this  case  led  to  more  extensive  burning  than 
otherwise,  and  conduced  to  the  freedom  of  the  man  from  nerve  lesions. 

It  was  found  that  where  flannels  touched  the  skin,  the  burns  were  super- 
ficial, but  where  the  cotton  trousers  came  into  contact  with  it,  the  burns  were 
uniformly  deeper. 

Classification  of  Climates 

Having  considered  the  elements  of  climate  in  relation  to  health,  we  can 
now  deal  with  the  influence  of  the  different  kinds  of  climate  on  human  life. 

First  we  must  adopt  some  form  of  classification  of  the  various  climates 
of  the  globe,  and  indicate  as  far  as  we  can  their  geographical  limits,  giving 
such  description  of  their  chief  features  as  may  be  necessary  by  way  of 
explanation. 

It  is  impossible  to  classify  all  climates  according  to  latitude  alone,  for 
various  influences,  such  as  warm  sea  currents  and  mountain  ranges,  consider- 
ably modify  the  effects  of  latitude  ;  nor  again  can  we  take  isothermal  lines 
as  our  sole  basis  of  division,  for  these  vary  with  the  season  and  the  month, 
and  the  isothermal  lines  of  January  difi'er  from  those  of  July.  Then  again  the 
relation  of  a  region  to  the  sea  coast  is  most  important,  as  in  a  tropical  country 
bordering  the  sea  the  great  heat  is  tempered  by  saline  breezes  night  and 
morning,  thus  rendering  it  tolerable  to  human  existence,  while  in  the  interior 
the  heat  may  be  extreme,  as  at  Marsak  in  Fezzan,  where  an  air  temperature 
of  130°  F.  was  registered,  and  at  Cooper's  Creek  in  Australia,  where  Burke 
and  Wills  died,  and  where  after  their  death  a  thermometer  graduated  up  to 
127°  F.  left  in  the  fork  of  a  tree  was  found  to  have  burst  by  the  expansion  of 
the  mercury,^  but  on  the  coast  the  temperature  is  lowered. 

The  change  of  temperature  is  of  course  a  most  important   feature  of 

'  Holmes's  System  cf  Surgery,  p.  398.  ^  Clinical  Societi/s  Transactions,  xiii.  p.  32. 

^  Scott,  Elementary  Meteorology,  p.  341. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  201 

climate,  and  the  regions  of  greatest  annual  range  are  situated  witliin  the 
areas  of  the  northern  hemisphere.  Near  Jakutck  in  Siberia  we  find  a 
small  district  with  the  enormous  range  of  100°  F.,  Jakutck  having  a  tem- 
perature of  65°  F.  in  its  warmest  and  — 44°-9  F.  in  its  coldest  month.  ]Jr. 
Supan^  has  established  several  laws  as  to  the  distribution  of  the  annual  range 
of  temperature,  among  which  are  the  following  : — ■ 

1.  The  range  increases  from  the  equator  towards  the  poles,  and  from  the 
coast  towards  the  interior  of  the  continent. 

2.  The  regions  of  extreme  range  in  the  northern  hemisphere  coincide 
approximately  with  the  districts  of  lowest  temperature  in  winter,  and  the 
range  curves  resemble  in  their  course  the  isotherms  of  January. 

8.  The  range  is  greater  in  the  northern  than  in  the  southern  hemi- 
sphere. 

4.  Li  the  middle  and  higher  latitudes  of  both  hemispheres,  with  the 
exception  of  Greenland  and  Patagonia,  the  western  coasts  have  a  less  range 
than  the  eastern.  This  is  mainly  attributable  to  the  general  prevalence  of 
westerly  winds  with  the  moisture  they  bring  with  them,  and  to  the  set  of 
warm  ocean  currents  on  these  shores. 

5.  In  the  interior  of  continents,  the  range  in  mountainous  districts  dimi- 
nishes with  the  height  above  the  sea.  This  appears  to  be  due  to  the  cold  air 
in  calm  weather  sinking  to  the  lowest  level  of  the  valley,  and  also  that  moun- 
tain sides  are  less  liable  to  the  visitations  of  fogs  than  the  vales  below. 

The  effect  of  warm  ocean  currents  on  the  temperature  of  certain  regions 
is  best  seen  in  the  influence  of  the  equatorial  currents  in  the  Atlantic,  Pacific, 
and  Indian  Oceans.  These  currents,  flowing  from  east  to  west,  are  the  result  of 
the  east  trade  winds,  producing  a  general  movement  of  the  surface  water  from 
■east  to  west  along  the  equator.  In  the  Pacific  Ocean  this  equatorial  current 
flows  till  it  meets  the  coast  of  New  Guinea,  when  it  divides  and  is  deflected 
into  two  streams,  one  flowing  southwards  and  striking  the  coast  of  Australia, 
and  the  other  northwards,  becoming  the  Euro  Siwo  current,  or  the  Great 
Black  Stream  of  the  Japanese  seas,  which  flows  outside  the  Philippines,  Loo 
■Choo  Islands,  and  Japan,  and  returning  eastwards  to  North  America,  washes 
the  southern  coast  of  Alaska  Promontory,  the  northern  side  being  bathed  by 
the  cool  current  coming  out  of  Behring's  Straits.  The  efi'ect,  according  to  Von 
Baer,  is  that  humming-birds  are  met  with  on  the  southern  shore,  while  the 
northern  one  is  frequented  by  walruses.  The  freedom  from  ice  enjoyed  by 
the  harbour  of  Sitka  and  the  coasts  of  British  Columbia,  while  the  shores  of 
Asia  in  corresponding  latitudes  are  fast  bound  in  it,  is  due  to  the  presence  of 
this  warm  current,^  which  passing  down  the  American  coast  eventually  rejoins 
the  equatorial  drift  current.  In  the  Indian  Ocean  the  water  is  embayed  on 
the  northern  side,  but  the  main  portion  of  this  part  of  the  equatorial  current 
passes  to  the  south  of  the  line  and  divides  opposite  to  the  Island  of  Mada- 
gascar, flowing  on  either  side  of  it,  the  inner  stream  forming  the  warm 
Agulhas  current,  which  washes  the  eastern  coast  of  the  Cape  of  Good  Hope. 
The  most  important,  however,  is  the  x\tlantic  equatorial  current,  which, 
flowing  eastwards,  divides  off  Cape  Eoque,  one  portion  turning  southward 
along  the  coast  of  Brazil  and  slightly  deflecting  the  isotherms  of  that 
region,  and  the  other  and  larger  portion,  following  the  north-east  coast  of 
South  America,  combines  with  the  westerly  current  of  the  north-east  trade, 
enters  the  Caribbean  Sea  and  reaches  the  Gulf  of  Mexico,  whence  it  issues 
through  the  Straits  of  Florida  as  the  Gulf  Stream,  a  majestic  current  upwards 
of  80  miles  broad  and  2,200  feet  deep,  with  an  average  velocity  of  four  miles 
an  hour  and  a  temperature  of  86°  F.     It  follows  the  line  of  the  American 

'  Scott,  0}}.  cit. 


202 


IIYGIEXE 


coast  to  Cape  Cod,  abutting  on  the  cold  Labrador  current,  T^■hich  is  30°  F.. 
colder,  and  then,  taking  an  easterly  direction,  spreads  over  the  North  Atlantic 
at  a  somewhat  diminished  velocity,  and  in  the  meridian  of  the  Azores  bifur- 
cates into  two  streams,  one  flowing  to  the  right  along  the  coast  of  Portugal, 
towards  the  Cape  Verdes,  and  the  other  moving  onwards  to  Northern 
Europe,  skirting  the  coasts  of  France,  Great  Britain  and  Ireland,  and  Scan- 
dhiavia  ;  then  rounding  the  North  Cape,  it  passes  the  White  Sea  and  Sea  of 
Kara  along  the  western  shores  of  Nova  Zembla  and  Spitsbergen,  and  it  is 
stated  that  its  influence  can  be  traced  into  Behring's  Straits.  The  current 
moves  slowly  off  the  British  coast,  according  to  Mr.  Scott  not  more  than 
an  inch  or  so  per  second,  but  that,  aided  by  the  westerly  winds  which  it 
probably  originated,  it  does  move,  is  proved  by  the  drift-wood  and  tropical 
products  from  the  Gulf  of  Florida  which  are  washed  upon  our  shores,  and 
even  on  the  shores  of  Spitzbergen. 

A  glance  at  any  map  of  the  isothennal  lines  for  January  (see  woodcut) 

ISOTHERMS    OF    NORTH    ATLANTIC. [WINTER] 
105 90 7y 60 ±5  30    15 0 IS 


■will  show  the  enormous  warming  influence  of  this  current,  for  the  isotherm 
of  41°  F.  runs  through  the  American  coast  near  Philadelphia  (latitude  40°)  and 
slants  in  a  north-easterly  direction  between  Iceland  and  the  Faroe  Islands 
(lat.  62°).  The  isotherm  of  45^°F.  starts  from  the  American  coast  at  about 
latitude  38°,  and  runs  to  the  north  of  Scotland  and  Ireland,  and  far  up  into 
Norway  beyond  latitude  60°,  the  warm  current  thus  causing  a  diversion  of  the 
temperature  lines  towards  the  north  of  upwards  of  20°  of  latitude.  It  is  in 
consequence  of  this  warming  influence  that  Great  Britain  and  Ireland  escape 
the  long  and  severe  winter  of  Labrador,  and  enjoy  their  comparatively  mild 
climate,  a  climate  marked  by  great  equability,  especially  on  the  coast  line, 
but,  as  the  heating  source  is  a  moist  one,  by  a  large  rainfall. 

Another  considerable  modification  of  the  effect  on  climate  of  latitude  is 
altitude  ;  for,  as  Herschel  says,  in  ascending  a  mountain  from  sea-level  to  the 
limit  of  perpetual  snow,  we  pass  through  the  same  series  of  climates,  as  far 
as  the  temperature  is  concerned,  that  we  should  by  travelling  to  the  polar 


INFLUENCE   OF  CLIMATE   ON  HEALTH  203 

regions  of  the  globe,  and  we  thus  see  cities  lilve  Quito  in  South  America,  iu 
proximity  to  the  equator,  but  at  an  elevation  of  10,000  feet,  enjoying  all  the 
year  round  a  cUmate  of  perpetual  spring  ;  and,  again,  the  mountain  sanitaria 
of  Madras,  at  elevations  varying  from  5,000  to  7,000  feet,  though  situated 
within  the  tropics,  afford  a  safe  retreat  for  Europeans  m  the  hot  season,  with 
a  mean  temperature  varying  from  50°  F.  to  70°  F.  and  with  a  moderate  rainfall. 

The  presence  of  mountain  ranges  exercises  great  influence  first  on  the 
rainfall,  and  secondly  on  the  shelter  from  winds.  ,    i,      i 

Districts  placed  to  the  lee  side  of  great  mountain  ranges  are  often  sheltered 
from  any  powerful  wind  which  may  prevail,  as  is  the  case  with  the  town  ot 
Pau  in  the  Pyrenees,  which,  lymg  immediately  at  the  foot  of  the  great 
Pyrenean  range,  is  sheltered  from  southerly  blasts,  while  the  slanting  hills  ot 
Les  Landes  to  the  north  protect  it  so  effectually  that  the  winds  from  the 
north  pass  over  the  town,  striking  the  Pyrenees  on  the  other  side.  Wmd  is 
almost  unknown  at  Pau ;  the  leaves  of  the  trees  hardly  move,  and  ram  otten 
falls  vertically  to  the  soil. 

Accepting  the  principle  of  latitude  with  these  modifications  therefore,  we 
would  roughly  class   climates  as  follows,   somewhat   after  the  method  ot 

Dr.  Henry  Bennet.  > 

1  Warm  Climates :  Equatorial ;  Trojncal ;  Szibtropical.—ClimB.te  ot 
regions  lying  between  the  equator  and  35°  latitude  N.  and  S.  Characterised 
by  high  temperature,  with  (as  a  rule)  heavy  rainfall,  and  dry  and  ramy 

2  Temperate  CZmafes.— Climates  at  regions  lying  between  35°  and  50° 
latitude,  with  four  well-marked  seasons— a  preponderance  of  rainfall  m 
autumn  and  winter— having  a  mean  temperature  from  50°  F.  to  60  1? . 
and  considerable  extremes. 

3  Cold  Climates.— Clim&ies  of  regions  lying  between  50  and  the  poles, 
marked  by  gradual  reduction  of  temperature  as  the  pole  is  approached,  the 
greatest  cold  being  10°  from  it.  The  season  there  consists  of  a  long  winter 
of  ten  months  and  of  a  few  weeks  of  summer.  Eainfall  small  and  generally 
in  form  of  snow.     Aurora  borealis  frequent. 

4  Marine  C/imates.— Characterised  by  the  presence  of  the  marine  in- 
fluence—i.e.  coasts,  islands,  peninsulas  washed  by  the  ocean  or  salt  seas, 
and  owmg  their  freedom  from  extremes  to  warm  currents  and  the  equahsmg 
influence  of  the  ocean.  Such  is  the  climate  of  Great  Britain,  Ireland,  of 
Norway,  and  of  many  islands.     We  also  include  in  this  division  the  climate 

experienced  in  sea  voyages. 

5.  Mountain  CZmates. -Characterised  by  diminished  barometric  pressure, 
increased  diathermancy,  and  by  extremes  of  temperature. 

Warm  Climates,  extending  fbom  the  Equatoe  to  35°  Latitude, 

I.E.    12^°    BEYOND    THE    TrOPICS 

This  division  comprises  the  greater  part  of  Africa  and  its  islands.  South 
Asia,  embracing  India  and  China,  Polynesia,  including  all  Austraha  except 
Victoria,  North  America  south  of  California,  and  South  America  north 
of  Uruguay,  with  the  West  Indies.  _ 

It  can  be  subdivided  into  equatorial,  tropical,  and  subtropical  groups,  and 
in  the  equatorial  the  mean  annual  temperature  is  from  80°  F.  to  84°  F.,  the 
mmimum  being  54°  F.  and  the  maximum  118°  F.  The  mean  temperature 
decreases  slowly  as  we  recede  from  the  equator,  the  decrease  not  amounting 
to  more  than  2°  F.  for  the  first  10°  lat.  The  difference  of  temperatm-e  durmg 
the  day  is  shght,  but  there  is  a  fall  at  night  from  radiation.     There  is  regular. 


204  HYGIENE 

but  slight,  diurnal  barometric  variation,  the  rainfall  is  about  forty  inches, 
and  it  is  evidently  this  which  tempers  and  reduces  the  otherwise  extreme 
heat,  as  it  is  not  found  that  the  highest  temperatures  or  the  highest  mean 
annual  temperatures  have  been  recorded  at  the  equator,  but  at  or  near  the 
tropics. 

The  line  of  perpetual  snow  is  also  higher  at  the  tropics  than  at  the  equator. 
The  hottest  known  regions  of  the  Avoiid  are  on  the  banks  of  the  Senegal,  the 
Tehama  or  coastline  of  Arabia,  and  the  deserts  in  the  interior  of  Australia, 
and  yet  none  of  these  are  situated  on  the  equator,  though  all  within  the 
tropics. 

These  facts  are  explained  partly  by  the  unequal  progress  of  the  sun  after 
the  equmox,  and  partly  by  the  prevalence  of  rain  at  the  equator,  attributed 
to  the  meeting  of  the  north  and  south  trade  winds  in  the  upper  atmosphere, 
and  consequent  precipitation  of  moisture.  This  is  said  to  be  most  marked 
in  the  region  of  calms  (equatorial)  in  the  Atlantic  and  Pacific  Oceans,  where 
the  rainfall  is  generally  heavy. 

In  India,  according  to  Blanford  and  Fayrer,  the  tropical  rainfall  depends 
on  the  physical  features  of  the  country  and  the  monsoon  winds.  There  is  a 
district  of  low  rainfall,  chiefly  consisting  of  low  hot  plains,  where  the  amount 
does  not  exceed  fifteen  inches  and  sinks  in  one  part  to  two  inches  ;  and  there 
are  regions  where  the  south-west  monsoon  strikes  mountain  ranges  like  the 
Khasia  Hills  and  the  Western  Ghauts,  where  it  rises  to  493  and  253  inches 
respectively. 

Prevalent  Diseases 

In  hot  climates,  the  organs  most  liable  to  disease  are  naturally  those 
-which,  owing  to  the  special  conditions,  are  overworked.  The  lungs  and 
heart  are  but  little  taxed,  and,  according  to  Parkes,  are  considerably  hghter 
after  death  than  in  temperate  or  cold  climates,  showing  dwindling  of  structure, 
probably  from  partial  lack  of  function,  while  the  hver,  spleen,  and  intestines 
are  all  more  or  less  the  seat  of  increased  function,  and  hence  are  liable  to 
become  diseased.  The  skin,  which  is  often  stimulated  to  increased  secretion 
in  tropical  countries,  is  continually  bathed  in  perspiration,  and  sometimes 
becomes  in  new  arrivals  in  the  tropics  the  subject  of  lichen  tropicus,  an 
affection  characterised  by  great  local  hyperaemia  and  swelling  of  the 
papillae. 

The  effect  of  great  heat  on  the  system  generally,  and  on  the  brain  in  par- 
ticular, is  shown  in  sunstroke,  but  its  influence  on  particular  organs  is 
more  difficult  to  define,  because  it  is  usually  combined  with  other  causes  of 
disease,  such  as  malaria,  the  drinking  of  impure  water,  and  the  consump- 
tion of  improper  food  and  various  forms  of  excess. 

"Whilst  a  great  many  diseases  are  assigned  to  the  influence  of  warm 
climates,  some  are  wrongly  so  attributed,  but  we  think  that  we  may  fairly 
ascribe  to  this  cause  the  following,  which  appear  to  have  their  birthplace 
within  the  tropics,  even  though  they  may  spread  at  a  later  date  to  more 
temperate  regions.  Such  are  sunstroke,  yellow  fever,  dengue,  cholera,  liver 
abscess,  dysentery,  and  various  kinds  of  intermittent  fever. 

Sunstroke. — The  exact  amount  of  influence  that  the  sun's  rays  exercise  in 
the  causation  of  sunstroke  is  not  ahvays  easy  to  determine,  because  in  many 
cases  there  are  other  conditions  present,  such  as  a  hot  close  atmosphere,  or  the 
body  overheated  by  exercise  and  unrelieved  by  perspiration  ;  but  it  is  curious 
to  note  the  rarity  of  sunstroke  in  mid-ocean,  even  in  the  tropics,  and  at  high 
altitudes,  and  yet  in  both  of  these  situations  the  solar  rays  are  exceedingly 
powerful,  though  the  temperature  of  the  atmosphere  in  either  case  is  never 
■excessive.     The  great   heat   of  the  sun's  rays   at  high   altitudes   depends 


INFLUENCE   OF  CLIMATE   ON  HEALTH 


205 


probably  on  the  rarefaction  of  the  atmosphere,  to  which  is  due  the  unequal 
diffusion  of  the  heat  and  great  difference  between  sunshine  and  shade 
temperatures.  In  the  Alps  this  is  more  marked  in  winter,  when  the  ground 
is  covered  with  snow,  and  the  sun's  rays  are  largely  reflected  from  the  surface. 
The  following  table  of  observations  on  the  solar  radiation  tliermometer 
(black  bulb  in  vacuo)  shows  the  mean  maxima  for  the  four  winter  months  at 
Greenwich,  Cannes,  and  Davos  during  the  years  1878-9,  and  indicates  the 
sun-power  at  a  high  altitude  to  be  even  greater  than  on  the  sunny  shore  of 
the  Mediterranean  : — ■ 


Greenwich. 


November,  1878 
December,  1878 
January,  1879 
February,  1879 


79°'9 
61-0 
63-8 
81-4 


Cannes 


122°0 
105-0 
1190 
1210 


Davos 


157°-0 
147-0 
141-0 
lCG-5 


The  contrast  between  sunshine  and  shade  at  high  altitudes  is  best 
exemplified  by  the  following  experiment,  which  was  made  at  Davos. 

InDecember  1878  the  writer  was  sitting  with  a  friend  after  luncheon,  about 
2  P.M.,  in  the  verandah  of  one  of  the  hotels,  sipping  coffee.  The  sun  was 
shining  brightly  and  they  felt  quite  warm,  though  snow  lay  all  around  them. 
He  placed  his  cup  of  coffee  in  the  shade,  and  moved  away  to  assist  his  friend, 
who  was  trying  to  hght  his  cigar  by  concentrating  the  sun's  rays  on  it  with  a 
burning  glass.  He  succeeded  in  doing  so,  and  the  writer  returned  to  his 
coffee,  to  find  it  frozen  ! 

Sunstroke,  or  Insolatio,  is  generally  the  result  of  exposure  to  solar  or  arti- 
ficial heat,  and  occurs  chiefly  in  tropical  countries,  but  occasionally  in 
temperate  climes.  Sir  Joseph  Fayrer  ^  states  that  the  most  frequent  cases 
are  those  coming  on  in  houses,  barracks,  and  tents,  by  night  or  in  the  day 
away  from  the  solar  rays,  and  the  subjects  of  sunstroke  are  more  likely  to 
be  those  debilitated  by  disordered  health,  by  dissipation,  and  by  over-fatigue, 
than  those  of  vigorous  constitution,  or  who  have  undergone  acclimatisation. 
Hindoo  natives  on  their  bare  heads  and  necks  endure  an  amount  of  sunshine 
which  would  be  fatal  to  a  European  ;  but  if  the  temperature  rise  above  a 
certain  standard  all  succumb,  the  natives  of  India  suffering  like  others,  and 
dying  from  the  effects  of  loo-mama,  or  '  hot  wind  stroke.' 

Fayrer  gives  three  varieties  of  sunstroke. 

I.  Showing  itself  in  exhaustion,  and  failure  of  the  heart's  action  in 

syncope. 

II.  A  condition  of  shock,  in  which  the  nerve-centres,  and  especially  the 
respiratory,  are  affected,  causing  rapid  failure  of  the  respiration  and  circulation. 

III.  Intense  pyrexia  due  to  vasomotor  paralysis,  and  to  the  nerve-centres 
being  over- stimulated  and  then  exhausted  by  the  action  of  heat  on  the  body 
generally. 

From  the  first  form  recovery  is  frequent,  but  the  second  or  asph^-xial 
form,  sunstroke  proper,  is  more  serious,  and  is  generally  due  to  the  direct 
action  of  the  sun's  rays  on  the  head  and  spine.  The  brain  and  nerve-centres, 
especially  the  respiratory  nerve-centre,  are  overwhelmed  by  the  sudden  elevation 
of  temperature,  and  respiration  and  circulation  fail,  the  failure  of  the  latter 
being  due  to  the  inhibitory  influence  of  the  vagus  ;  the  heart  after  death 
being  found  contracted.  The  symptoms  of  this  form  are  generally  those  of 
violent  injury  to  the  nerve-centres,  unconsciousness  and  cold  skin,  feeble 
pulse,  and  death  from  rapid  failure  of  respiration  and  circulation. 
*  Quain's  Dictionary  of  Medicine.     Article  '  Sunstroke.' 


206  HYGIENE 

The  third  form,  the  so-called  '  heat  fever,'  is  an  intense  state  of  feverish- 
ness,  the  effect  of  heat  on  the  nerve-centres,  and  through  them  on  the 
vasomotor  system,  resulting  in  the  raising  of  the  body  temperature,  generally 
by  heat,  solar  or  artificial,  as  it  may  occur  independently  of  the  direct  solar 
rays.  This  form  comes  as  frequently  at  night  or  in  the  shade  as  by  day, 
especially  in  persons  exhausted  by  fatigue,  dissipation,  or  overcrowding  in  an 
impure  atmosphere. 

According  to  Fayrer,  from  whose  admirable  article  most  of  this  descrip- 
tion is  taken,  the  body  temperature  rises  to  108°  F.,  110°  F.,  or  even 
higher,  the  brain,  medulla,  and  cord,  the  nerve-centres  generally,  and  especially 
the  respiratory,  suffer  from  over-stimulation,  followed  by  exhaustion  :  respira- 
tion and  circulation  fail,  there  is  dyspnoea  of  a  hurried  gasping  kind,  great 
restlessness,  thirst,  fever,  freqiient  micturition  and  pungent  heat  of  skin, 
which  is  sometimes  dry,  sometimes  moist.  The  pulse  varies,  being  some- 
times full  and  laboured,  sometimes  quick  and  jerking,  the  face,  head,  and  neck 
are  congested  to  lividity ;  the  pupils,  at  first  contracted,  may  dilate  before 
death.  Delirious  convulsions  (often  epileptiform),  coma,  relaxation  of  the 
sphincters,  suppression  of  urine,  prelude  the  fatal  termination,  but  not  in- 
frequently partial  recovery  takes  place,  to  be  followed  later  by  relapse  and 
death.  The  mortality  of  sunstroke  is  about  45  to  50  per  cent.,  but,  of  those 
"who  recover,  many  are  permanently  injured,  either  in  brain  power,  or  in  the 
general  health,  and  we  find  as  a  result  impairment  of  memory,  nervous  irri- 
tability, headache,  and  even  epilepsy,  partial  paraplegia,  partial  or  complete 
blindness,  and  extreme  intolerance  of  heat,  and  especially  of  the  sun's  rays. 

In  fatal  cases  of  sunstroke,  the  lungs  and  the  pulmonary  system  are 
often  deeply  congested,  the  heart  is  firmly  contracted  from  coagulation  of 
myosin,  the  venous  system  is  gorged,  and  the  body  marked  by  petechias. 
The  blood  is  more  fluid  than  usual,  acid  in  reaction,  the  globules  have  less 
tendency  than  usual  to  form  rouleaux,  and  are  deficient  in  oxygen.  The 
body  for  some  time  after  death  retains  a  high  temperature,  and  the  viscera 
when  first  opened  feel  pungently  hot,  and  the  incisions  drip  dark  blood. 

The  brain  and  membranes  are  intensely  congested,  and  sometimes  there 
are  serous  effusions  into  the  ventricles,  and  sometimes  haemorrhage  into  the 
brain  substance  ;  but  the  cause  of  death  is  generally  asphyxia,  but  apoplexy 
and  the  most  important  changes  are  found  in  connection  with  the  thoracic 
viscera. 

Yellow  fever  may  be  said  to  be  limited  to  subtropical  and  tropical  countries, 
as  it  is  only  found  between  32°  70'  north,  and  22°  5'  south  latitude.  It 
prevails  in  the  West  Indies,  the  Gulf  of  Mexico,  extending  to  the  southern 
of  the  United  States  of  America,  and  in  South  America,  as  far  south  as  Eio 
Janeiro.  It  has  at  times  also  crossed  the  Atlantic  and  prevailed  on  the  West 
Coast  of  Africa,  between  Cape  Verd  14°  54'  N.  latitude,  and  Cape  Coast  Castle, 
5°  7'  N.  latitude,  and  has  extended  to  the  ports  of  Western  Europe ;  cases 
have  also  been  seen  in  the  Northern  States  of  America.  Its  relation  to 
climate  is  singularly  distinct.  It  requires,  for  its  existence  and  diffusion,  a 
temperature  of  not  less  than  70°  F.,  and  it  is  increased  by  moisture,  and  thus 
it  can  only  prevail  during  hot  and  moist  seasons.  Nevertheless,  it  is 
extinguished  by  a  heavy  rainfall,  by  cold  winds,  or  by  frost  or  snow.  As  a  rule 
it  is  confined  to  the  sea-level,  and  only  rarely,  if  ever,  is  found  at  any  height, 
though  it  has  on  one  occasion  been  known  to  invade  towns  at  considerable 
elevation  in  the  Andes.  It  chiefly  infests  seaports,  and  for  the  most  part 
the  worst  and  most  crowded  quarters,  and  it  spreads  almost  entirely  by 
infection,  and  generally  attacks  strangers  coming  from  northern  climates  in 
preference  to  natives.    Acclimatisation  gives  immunity  for  one  region,  which- 


INFLUENCE   OF  CLIMATE   ON  HEALTH  207 

Tiowever,  may  be  lost  by  a  change  of  residence  to  another  country.     Negroes 
.and  Chmese  seem  exempt  from  this  disease. 

Prevaihng  as  yellow  fever  does  in  tropical  comitries  and  almost  solely  in 
■crowded  cities  on  the  seaside  or  the  banks  of  rivers,  it  is  probably  due  to  a 
poison  generated  or  fostered  by  local  pestilential  conditions,  and  in  many 
districts  improved  sanitation  has  reduced,  and  may  still  further  reduce,  its : 
prevalence. 

Dengue  is  another  disease  confined  to  the  tropics,  and  prevails  between 
37°  47'  N.  and  23°  28'  S.  latitude,  in  summer  and  early  autumn.  It  has 
appeared  as  an  epidemic  in  the  West  Indies  and  Central  America,  but  it  occurs 
principally  in  India,  China,  and  Egypt.  It  is  an  infectious  fever  characterised 
by  severe  continuous  arthritic  and  muscular  pains,  debility  and  prostration, 
an  initial  and  terminal  rubeoloid  or  scarlet  rash,  pyrexia  rising  to  103°  F.  or 
«ven  105°  F.,  but  speedily  declining,  though  subject  to  remissions  or  relapses  ; 
pain  and  swelhng  of  joints  and  glands,  and  orchitis,  and  visceral  complica- 
tions, such  as  diarrhoea  and  dysentery,  and  boils  are  also  common  symptoms. 

Its  period  of  incubation  is  five  to  six  days,  and  the  duration  of  the  com- 
]plaint,  when  free  from  sequelae,  about  eight  days  ;  but  it  is  sometimes  pro- 
longed to  weeks,  and  like  influenza,  which  it  is  said  to  resemble,  it  often  leaves 
the  patient  in  a  very  weak  and  shattered  condition. 

Dengue  has  appeared  occasionally  m  a  more  severe  form  than  the  above, 
■with  symptoms  of  hyperpyrexia,  coma,  cyanosis,  and  oedema,  of  the  lungs 
'(Charles),  but  as  a  rule  it  is  not  a  fatal  disease.  It  never  occurs  in  England,  and 
from  its  appearing  as  an  epidemic  and  spreading  over  large  tracts  of  country 
without  any  apparent  reason,  its  development  has  been  assigned  to  some 
unknown  cosmic  and  atmospheric  conditions  (Fayrer). 

Asiatic  cholera,  though  its  epidemics  are  diffused  over  nearly  the  whole 
globe,  tropical,  temperate,  and  cold  countries  being  visited  in  succession,  has 
its  home  in  India,  where  it  is  endemic,  in  a  region  which  has  been  described 
by  Bryden  as  bounded  on  the  east  by  the  91st  or  92nd  parallel  of  longitude, 
on  the  v/est  by  the  81st  parallel,  on  the  north  by  the  latitude  of  27°  N.,  and 
on  the  south  by  the  shores  of  the  Bay  of  Bengal  (including  the  delta  of  the 
Oanges  and  the  territory  at  the  mouths  of  the  Mahamuddy).  This  region 
■extends  from  the  mountainous  districts  of  the  Brahmapootra  to  the  hill 
regions  of  Eajmahal  and  Cuttack,  and  on  its  northern  border  along  the  Terai 
from  Lower  Assam  to  the  district  of  Purnea.  Of  this  region  the  delta  of 
the  Ganges  with  a  very  high  annual  temperature  is  assigned  as  the  focus  of 
cholera,  and  the  cholera  mortality  of  the  Presidency  of  Bengal  is  the  greatest 
in  India,  the  eastern  portion  of  the  district  being  most  frequently  attacked. 
-Cholera  becomes  virulent  and  spreads  from  this  centre  often  to  other  parts 
■of  India  and  eventually  to  other  countries  of  Asia,  to  Africa,  and  to  Europe 
and  America,  North  and  South  ;  apparently  choosing  the  great  lines  of 
human  intercourse  for  its  channel  of  diffusion  ;  but,  what  we  as  climatolo- 
gists  are  most  concerned  with,  choosing  the  warm  and  rainy  seasons  for  its 
march,  and  rapidly  disappearing  on  the  approach  of  cold  weather.  The 
•disease  generally  travels  westwards  and  somewhat  slowly,  but  it  has  been 
proved  to  be  conveyed  by  both  sea  and  land-routes.  The  infective  material 
has  been  proved  to  be  principally  contained  in  the  alvine  excretions,  which, 
becoming  mixed  with  the  water-supply  of  a  city  or  town,  may  rapidly  poison 
a  whole  community,  the  smallest  quantity  of  the  infective  material  impart- 
ing to  enormous  volumes  of  water  the  power  of  propagating  cholera  (Simon). 
The  disease  may  also  be  communicated  directly  by  cholera  patients  in 
crowded  and  badly  ventilated  rooms,  as  well  as  from  their  soiled  hnen. 

Seaports  are  generally  attacked  by  cholera,  and  a  saline  atmosphere  affords 


208  HYGIENE 

no  protection  ;  but,  on  the  otlier  hand,  it  is  ascertained  that  a  certain  altitude 
above  sea-level  has  often  been  shown  to  confer  immunity,  and  in  India  it 
is  the  practice  to  remove  troops  to  hill  stations  when  the  disease  breaks  out. 

Switzerland  was  exempt  during  most  of  the  great  epidemics,  and  both  m 
England  and  France  it  was  found  that  more  or  less  elevated  districts  sufiered 
far  less  than  low-lying  ones. 

The  diffusion  ot  cholera  appears  to  follow  the  course  of  rivers,  and  Hirsch 
holds  this  to  be  due  to  the  more  copious  saturation  of  the  ground,  coupled 
W'ith  the  retention  of  organic  matters  undergoing  decomposition,  and  he 
remarks  that  one  of  the  best  proofs  of  this  is,  that  the  amount  of  sickness 
diminishes  in  proportion  as  the  disease  in  its  progress  travels  further  from 
the  margin  of  the  river  basin. 

Dysentery,  Diarrhoea,  and  Tropical  Abscess  of  the  Liver. — These  diseases 
have  been  placed  together  in  the  same  category  as  apparently  due  to  similar 
causes,  and  forming  in  many  patients  various  links  in  the  same  chain  of 
pathological  events.  How  far  they  are  due  to  tropical  climates  alone,  or  to 
the  mfluence  of  malaria  or  to  impure  drinking  water,  is  not  always  clear,  for 
in  many  instances  all  these  factors  are  at  work  together,  and  unquestionably 
a  good  supply  of  drinking  water  has  lowered  the  death-rate  from  diarrhoea 
and  dysentery  in  many  tropical  countries,  as  much  as  a  reduction  in  the 
quantity  of  alcohol  consumed  by  English  troops  has  diminished  the  number 
of  cases  of  hepatitis  and  liver  abscess. 

The  connection  of  malaria  with  dysentery  has  always  been  strongly  held 
by  some  Indian  surgeons,  who  are  able  to  point  to  the  fact  of  both  diseases 
diminishing  and  often  disappearing  under  the  efficient  draining  of  swampy 
districts  ;  but  the  opinion  gains  daily  that  though  dysentery  may  be  due  in 
some  cases  to  malaria  or  to  any  poison  congesting  the  portal  system  and  the 
spleen  and  the  liver,  the  greater  part  of  dysentery  arises  from  other  causes, 
such  as  impure  water,  bad  drainage,  and  especially  the  accumulation  of 
dysenteric  stools,  and  improper  food.  Hirsch,  too,  considers  that  it  is 
neither  '  in  high  temperatures,  nor  in  an  extreme  range  of  the  thermometer 
inducing  chills,  that  we  have  to  look  for  the  endemic  factor  of  dysentery  and 
diarrhcea,'  though  he  admits  '  that  extreme  fluctuations  of  the  temperature 
(iji  so  far  as  they  induce  chill)  are  among  the  most  inviting  opportunities  for 
the  malady  to  start.' 

Nevertheless,  whilst  admitting  that  dysentery  may  occur  in  any  country 
or  clime  under  special  circumstances  of  bad  water,  food,  and  drainage,  as  has 
been  repeatedly  demonstrated  in  outbreaks  during  campaigns,  we  cannot 
disguise  the  fact  that  it  is  far  more  common  in  tropical  climates  than  in 
temperate,  and  we  must  accept  heat,  though  not  necessarily  moisture,  as  an 
element,  though  not  as  an  absolutely  essential  one,  of  its  causation. 

Abscess  of  the  liver,  though  known  in  temperate  and  cold  climates,  where 
it  is  a  rare,  and,  for  the  most  part,  a  secondary  disease,  is  tolerably  common  in 
the  tropics,  and  especially  in  India,  where  it  forms  a  conspicuous  feature  in 
the  disease  statistics  of  both  the  European  and  native  troops,  and  is  partly 
due  to  the  extreme  heat  to  which  they  are  exposed,  and  partly  to  alcoholic 
excesses. 

Malaria. — This  poison  is  found  in  operation  not  only  in  tropical,  but  in 
temperate  climates,  though  not  in  cold  ones,  but  as  it  is  far  more  common 
and  reaches  its  greatest  point  of  concentration  and  virulence  in  tropical 
climes,  we  have  selected  the  division  of  warm  cHmates  for  its  consideration, 
alluding  in  passing  to  its  manifestations  in  temperate  climates.  Though 
some  advance  has  been  made  by  recent  investigations  in  our  knowledge  of 
the  intimate  nature  of  malaria,  it  cannot  be  said  that  full  explanation  has 


INFLUENCE  OF  CLIMATE   ON  HEALTH  209 

yet  been  given  of  the  variety  of  conditions  of  soil  and  atmosphere  under 
which  it  prevails,  the  conditions  being  often  of  an  almost  opposite  character, 
as,  for  instance,  in  India  it  is  found  in  the  water-logged  marshy  ground  of 
the  Terai,  and  also  in  the  sandy  dry  soil  of  the  Deccan.  The  presence  of 
water,  and  especially  of  salt  water  in  large  amount  in  a  marsh,  appears  to 
reduce  the  malarious  influence,  but  the  drying  up  of  a  marsh,  or  of  a  river 
bed,  or  the  subsidence  of  a  flood,  is  generally  the  signal  for  an  outbreak  of 
intermittent  fever. 

According  to  Dr.  W.  Maclean,  the  remittent  fever  which  devastated  the 
British  army  in  the  Peninsular  War,  when  encamped  on  the  sunburnt  plains 
of  Ciudad  Eodrigo,  may  be  explained  by  these  plains  having  been  the  scene 
of  floods,  which  had  recently  dried  up  under  the  scorching  sun  of  a  Spanish 
summer.  Fayrer  considers  that  subsoil  water  or  damp  is  the  most  essential 
condition  of  malaria,  and  especially  if  the  subsoil  be  impregnated  by  a 
certain  amount  of  stagnant  moisture,  and  that  this  is  probably  present  in 
many  of  the  localities  in  which  the  appearance  of  malaria  is  so  difficult  of 
explanation. 

According  to  him,  malaria  is  at  its  worst  in  India  in  the  drying-up  season 
after  the  rains,  but  during  the  rains  it  is  less  severe.  The  turning  up,  or 
excavation  of  new  soil,  generally  increases  the  danger,  but  the  cultivation, 
draining,  and  cropping  of  the  same  soil  generally  diminishes  or  abolishes  it. 

Parkes  gives  as  examples  of  soils  with  the  largest  organic  emanations, 
and  therefore  most  likely  to  be  the  source  of  the  malaria — 

1.  AUuvial  soils,  old  estuaries,  and  deltas. 

2.  Sands,  if  there  be  impermeable  clay,  or  marly  subsoil,  and  old  water- 
courses. 

3.  The  lower  parts  of  chalk,  if  there  be  a  subsoil  of  gault  or  clay. 

4.  Weathered  granite  trap  rocks,  if  vegetable  matter  has  become  inter- 
mixed. 

5.  Eich  vegetable  soils  at  the  foot  of  hills. 

Klebs  and  Tommasi-Crudeli  discovered  in  the  air  and  soil  of  the  Eoman 
Campagna  a  microscopic  fungus,  consisting  of  numerous  moveable  shining 
spores  of  a  longish  oval  shape.  This  '  bacillus  malarige,'  as  it  has  been 
called,  is  capable  of  artificial  cultivation  in  suitable  media,  and  when  injected 
into  dogs  produces  well-marked  symptoms  of  intermittent  fever,  and  their 
spleens  are  shown  to  enlarge.  The  bacillus  malarise  has  been  detected  in 
the  blood  of  human  patients,  during  the  period  of  invasion  of  the  fever,  but 
during  the  acme  it  disappears,  and  spores  only  can  be  discovered.  It  has 
also  been  found  in  the  spleen  of  human  subjects,  and  in  the  marrow  of  the 
bones  of  the  animals  inoculated.  The  conditions  of  growth  of  this  bacillus 
are  heat  and  moisture.  The  proof  of  malaria  residing  in  the  soil  is  shown 
by  the  fact  that  shutting  off  the  soil  by  paving,  as  has  been  done  in  Eome, 
abolishes  the  malaria,  and  even  when  the  sun's  rays  are  intercepted  by  fog 
or  cloadthe  fever  is  lessened. 

Apart  from  other  elements,  heat  seems  in  all  climes  to  be  the  deter- 
mining cause  of  malarious  fever,  whether  remittent  or  intermittent,  as  the 
cases  of  ague  occurring  in  England,  in  Essex  and  Lincolnshire,  are  developed 
during  the  summer  and  autumn,  and  on  the  shores  of  the  Mediterranean 
tracts  of  land  which  would  be  exempt  from  malaria  in  this  country  become 
teeming  with  miasm  under  the  influence  of  the  powerful  southern  sun. 
This  is  the  case  of  the  deltas  of  rivers  in  the  south  of  France  and  Italy,  and 
the  embouchures  of  streams  in  Corsica  and  Sardinia.  In  some  places,  as  at 
the  mouth  of  the  Var,  the  embanking  of  the  river  has,  by  raising  the  river 
bed,  developed  malaria  among  the  dwellers  on  either  side. 

VOL.   I.  p 


210  HYGIENE 

On  the  west  coast  of  Corsica,  the  streams  discharge  into  the  sea  by  rochy 
chatinels,  the  greater  part  of  the  coast  being  of  that  character,  and  there 
only  exist  small  deltas  at  their  mouths,  but  these  imder  the  solar  inlluence 
produce  malaria  in  the  summer,  which  is  wafted  by  the  westerly  winds  up 
the  mountain  valleys  for  a  considerable  distance.  It  is  held  by  many 
authorities  that  the  summer  isotherm  of  58°  F.  to  60°  F.  limits  the  occur- 
rence of  intermittent  fever,  and  that  regions  where  the  mean  summer 
temperature  does  not  reach  this  iigure  are  exempt  from  malaria,  a  conclu- 
sion abundantly  proved  by  evidence  ;  and  Ilirsch  remarks  that  confirmation 
of  this  is  notably  found  in  the  fact  that  the  extent  and  intensity  of  the 
disease  in  malarious  foci  at  the  different  seasons  of  the  year  are  in  direct 
proportion  to  the  height  of  the  respective  temperatures,  and  also  in  the  fact 
that  the  great  epidemics  and  pandemics  have  been  immediately  preceded  by 
hot  years,  or  have  coincided  Avith  them. 

The  effect  of  malarious  poison  on  the  human  system  is  as  conspicuous 
as  its  action  is  msidious.  First  we  get  the  nervous  system  attacked  with 
neuralgic  migraine,  or  some  other  form  of  nerve  storm  ;  then  comes  asthma, 
another  neurosis  so  commonly  associated  with  malaria.  And  later  the 
morbid  changes  in  the  spleen  and  liver,  and  in  time  those  degenerative 
changes  in  the  tissues  which  give  to  the  patient  the  appearance  of  malarious 
cachexia.  As  the  poison  increases  in  intensity,  and  the  climate  becomes 
hotter,  we  get  fever,  at  first  intermittent,  quartan,  tertian,  and  quotidian, 
and  further  south  we  find  the  remittent  form  so  common  in  the  tropics. 

Fayrer  teaches  ua  that  natives  of  India  are  attacked  quite  as  much  as 
Europeans  by  malarious  fever,  and  even  that  dogs,  and  horses,  and  cattle  are 
affected.  The  mortality  of  British  troops  in  Bengal  from  fever  is  less  than 
3  per  1,000,  but  that  of  the  natives  is  nearly  25  per  1,000,  and  the  difference 
is  attributed  to  the  natives  being  poorly  fed  and  badly  housed. 

We  will  now  close  our  account  of  warm  climates  and  their  influence  on 
health,  having  indicated  the  principal,  though  by  no  means  all,  the  diseases 
which  are  assigned  to  them,  with  the  conclusion  that  for  Europeans  who 
have  gone  through  the  ordeal  of  such  complaints,  and  survived  them,  change 
of  chmate,  and  especially  a  return  to  their  own  temperate  climate,  is  the  best 
means  of  restoring  health. 

The  climate  of  the  desert  forms  an  important  sub-group  of  warm  climates, 
and,  as  it  is  a  good  example  of  the  combination  of  warmth  and  dryness,  it 
merits  a  few  words  of  special  description.  As  an  instance  may  be  cited  the 
tract  commencing  Avith  the  Great  Sahara  and  extending  eastwards  through 
Arabia  to  Persia,  and  therefore  including  the  Egyptian  desert ;  other  examples 
are  the  desert  of  Gobi  in  Chinese  Tartary,  the  Kalahari  in  South  Africa,  the 
Great  Salt  Lake  district  in  North  America,  and  the  vast  deserts  in  the  interior 
of  Austraha. 

Let  us  take  Egypt  as  a  type  of  the  desert  chmate,  including  its  principal 
features. 

First,  its  dryness.  The  rainfall  at  Cairo  is  1-22  inches,  occurring  in 
occasional  showers  lasting  15  to  80  minutes,  seldom  longer.  At  Thebes  rain 
is  exceedingly  rare,  and  in  the  province  of  Esneh  it  is  almost  unknown.  The 
number  of  days  on  which  rain  falls  at  Cairo  varies  from  12  to  15,  and  is  less 
in  Upper  Egypt,  but  the  state  of  the  atmosphere  is  best  shown  by  the  hygro- 
meter, as  on  the  Nile  the  difference  between  the  wet  and  dry  bulbs  sometimes 
amounts  to  24°  F.  and  the  annual  relative  humidity  percentage  is  68*46. 

The  best  proof  of  the  dryness  of  the  desert  atmosphere  is  to  be  seen  in  the 
state  of  the  mummies,  which  there  remain  unchanged  for  centuries,  though 
their  removal  to  a  moister  atmosphere,  such  as  that  of  Alexandria,  causes 
their  immediate  decomposition. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  211 

Second,  its  purity.  Prince  Zagiell "  has  shown  that  while  atmospheric 
air  contains  as  a  rule  4  parts  of  carbonic  acid  in  10,000  parts,  the  air  of  the 
desert  contains  no  trace  of  this  gas.  Moreover,  putrefaction  appears  checked, 
and  meat,  when  exposed  to  the  open  air,  becomes,  after  three  weeks,  dry  and 
completely  mummified,  without  any  sign  of  decomposition.  Zagiell  has  also 
noted  that  vegetable  fermentation  does  not  take  place,  and  ripe  fruits  when 
left  on  the  trees  dry  up  without  becoming  rotten.  This  aseptic  quality  of 
the  air  is  further  demonstrated  by  the  rapid  healing  of  wounds  and  ulcerations 
to  which  the  surgeons  bear  testimony,  and  also  by  the  fact  that  phthisis 
appears  to  be  unknown  among  the  tribes  of  the  desert,  though  cases  are 
to  be  found  in  Cairo,  where  the  evil  influences  of  a  great  city  prevail. 

Third,  the  difference  between  night  and  day  temperatures  due  to  the 
effect  of  radiation.  This  has  been  noted  by  Dr.  Marcet  ^  even  in  winter  to 
amount  to  between  17°  and  18°  F.  There  appears  to  be  two  seasons,  one 
comparatively  hot,  and  one  comparatively  cool,  but  in  both  the  effects  of 
radiation  show  themselves.  The  winter,  consisting  of  November,  December, 
January,  and  February,  gives  a  mean  of  58°"3  F.,  the  summer  average  being 
76°'l  F.  The  maximum  of  five  years'  observations  at  theKhedivial  Observatory 
in  a  suburb  of  Cairo  was  111°  F.,^  occurring  July  13,  1888,  and  on  a  night 
of  January,  1887,  the  minimum  of  35°  F.  was  reached. 

Prince  Zagiell's  observations,  taken  every  two  hours  in  the  twenty-four, 
show  the  maximum  to  be  attained  between  2  and  3  p.m.,  and  to  vary  in  winter 
between  79°'2  F.  and  83°"7  F.,  while  the  minimum  is  reached  between  3  and 
4  a.m.,  and  varies  from  38°"7  F.  to  39°"9F.,  a  range  of  45  degrees.  Snow 
is  quite  unknown,  though  ice  has  been  noticed  at  night  on  extremely  rare 
occasions. 

In  Middle  and  Upper  Egypt,  during  summer,  the  sand  becomes  so 
intensely  heated  during  the  daytime,  that  although  the  radiation  is  great  at 
night,  the  air  remains  warm  from  the  direct  action  of  the  emitted  heat,  and 
this  is  especially  the  case  with  reference  to  the  layer  of  atmosphere  over  the 
soil.*  During  that  season  in  Middle  Egypt  the  temperature  rises  by  day  from 
96°-5  F.  to  104°  F.  and  falls  regularly  at  night  from  86°  F.  to  72°-5  F.,  while 
in  Upper  Egypt  the  temperature  in  the  daytime  ranges  from  95°  F.  to  113°  F. 
and  falls  at  night  from  90°-5  F.  to  65°-7  F. 

The  winds  which  generally  prevail  in  Egypt  are  from  the  north,  and 
enable  the  dahabeahs  and  other  sailing  vessels  to  ascend  the  Nile  against  its 
strong  current.  These  winds  are  cool  and  refreshing  ;  but  there  is  one,  the 
Khamseen,  which  possesses  the  very  opposite  qualities,  and  is  very  pernicious 
to  animal  and  vegetable  life. 

The  Khamseen  blows  from  the  south  or  south-east,  the  more  easterly 
variety  being  the  most  disagreeable.'^  It  generally  lasts  three  days,  but  may 
extend  to  seven.  This  wind  is  of  rare  occurrence,  the  number  of  days  being 
only  from  four  to  twenty  in  the  year.  The  sky  is  clouded  by  fine  sand  held 
in  suspension  and  rendering  the  atmosphere  grey  in  colour  and  obscuring  the 
sun's  rays,  so  that  the  appearance  is  like  that  of  a  London  fog.  But  the  air 
is  hot  and  dry,  and  when  the  wind  veers  round  to  the  north  a  fall  of  some- 
times 30°  F.  takes  place.  The  Khamseen  shrivels  up  roses  and  other  flowers, 
and  will  even  warp  and  crack  unseasoned  wood.  The  effect  on  human 
beings  is  to  cause  listlessness  and  languor,  not  only  in  Europeans,  but  in 

'  See  Marcet,  Southern  and  Siuiss  Health  Besorts,  p.  207. 
-  Qiiarterly  Journal  of  Meteorological  Science,  October  1885. 
5  F.  M.  Sandwith,  Egypt  as  a  Winter  Resort,  p.  24. 
■•  Marcet,  Southern  and  Swiss  Health  Besorts,  p.  207. 
'  Sandwith,  Egypt  as  a  Health  Besort. 

P  2 


212  HYGIENE 

the  natives,  ^vllo  are  seen  lying  about  unfit  for  tlieir  work.  It  has  not  been 
proved  to  be  harmful,  but  rather  the  reverse,  to  phthisical  and  bronchitic 
patients,  but  the  rapid  fall  of  temperature  which  succeeds  has  to  be  carefully 
guarded  against. 

The  climate  of  the  desert,  as  will  bo  seen,  is  warm  and  very  dry  and 
aseptic,  and  as  such  has  proved  of  great  benefit  in  the  treatment  of  phthisis 
and  scrofula. 

The  writer's  statistics  show  that  out  of  20  consumptives  who  spent  2G 
winters  in  Egypt,  no  less  than  G5  per  cent,  improved,  25  per  cent,  remained 
stationary,  while  only  10  per  cent,  deteriorated.  Dry  pleurisy,  bronchitis,  and 
spasmodic  asthma,  especially  if  combined  with  emphysema,  benefit  largely 
by  a  winter  in  Egypt,  and  chronic  rheumatism  is  wonderfully  alleviated. 

Ophthalmia  and  other  eye  afl'ections  prevail  largely  in  this  country,  and 
are  in  part  attributed  to  the  climate  and  soil.  A  large  class  of  nerve  affec- 
tions are  greatly  benefited  by  a  winter's  residence  in  Egypt,  and  specially 
by  life  in  a  dahabeah. 

The  climates  of  Algeria  and  Morocco  deserve  a  passing  notice,  because, 
though  in  close  proximity  to  the  Great  Sahara  Desert,  they  differ  greatly 
from  the  climate  of  the  Egyptian  desert ;  and,  again,  though  they  form  the 
southern  shore  of  the  Mediterranean,  their  meteorology  presents  a  great 
contrast  to  that  of  the  northern  shore. 

The  French  province  of  Algeria  is  a  strip  of  country  about  1,200  miles 
from  east  to  west,  and  200  miles  from  north  to  south,  extending  into  the 
Great  Sahara  Desert,  being  situate  between  32°  and  37°  north  latitude. 

The  mountain  ranges  of  the  Great,  Middle,  and  Lesser  Atlas  traverse 
the  province  from  east  to  west,  and  form  three  chains  more  or  less  parallel 
to  each  other.  The  Lesser  Atlas  skirts  the  Mediterranean  at  a  distance 
varying  from  1  to  15  miles,  and  is  separated  from  the  Middle  Atlas  by  the 
fertile  valley  of  the  Chelifi',  and  the  Middle  Atlas  is  again  divided  from  the 
chain  of  the  Great  Atlas  by  the  Algerian  desert,  an  elevated  plain  contain- 
ing salt  water  lakes,  with  an  altitude  of  several  thousand  feet.  Beyond  the 
Great  Atlas  lies  the  Sahara  Desert,  which,  according  to  Dr.  Bennet,  is  the 
key  to  the  Algerian  climate,  and  converts,  what  would  be  a  dry,  into  a  moist 
clime. 

The  atmosphere  which  overlies  this  immense  rainless  tract  of  desert, 
becommg  heated  both  in  winter  and  summer,  must  rise  into  the  higher 
strata,  and  thus  form  a  vacuum,  which  the  cooler  and  heavier  air  of  the 
Mediterranean  basin  rushes  down  to  fill.  The  latter  is  sucked  in  over  the 
summits  of  the  Atlas  ranges,  consequently  in  Algeria  the  regular  winds  are, 
and  must  be,  either  north-east  or  north-west  winds,  and  south  winds  can, 
and  only  do,  blow  exceptionally. 

These  northerly  winds,  coming  from  the  Mediterranean  Sea  or  the  Atlantic 
Ocean,  are  moist  winds,  and  when  they  come  into  contact  with  the  Atlas 
mountains  are  at  once  cooled  and  deposit  their  moisture  in  copious  and 
frequent  rain  over  the  entire  Algerian  or  Atlas  region,  and  extend  into  the 
desert  itself,  250  miles  from  the  sea.  Consequently  the  rainfall  at  Algiers 
is  heavy,  about  32  inches,  distributed  over  87  days,  occurring  chiefly  in 
winter.  The  year  is  divided  into  two  seasons,  the  hot  and  the  rainy,  the 
former  extending  from  April  to  November,  and  the  latter  from  November 
to  April,  the  largest  rainfall  and  the  greatest  number  of  rainy  days  occurring 
in  November,  December,  and  January.  In  the  summer  the  rain  often  falls 
for  several  months,  and  occasionally  seasons  of  drought  have  occurred  even 
in  winter.  Such  dry  seasons  are  generally  accompanied  by  a  plague  of 
locusts,  which  invade  Algeria  from  the  desert,  penetrating  the  Atlas  through 


i 


INFLUENCE   OF  CLIMATE   ON  HEALTH  213 

the  passes  and  roads  constructed  by  man,  and  devastating  the  fertile  valleys 
of  the  Chehff  and  destroying  whole  crops  of  cereals. 

The  rainfall  of  Algeria  increases  on  proceeding  eastward.  Of  the  three 
provinces  into  which  the  country  is  divided,  Oran,  the  most  westerly,  has  the 
least  rainfall.  Constantine,  the  easternmost,  has  the  greatest ;  while  in  Algiers, 
■the  central  one,  the  rainfall  is  double  that  of  Oran,  and  about  half  that  of 
Constantine.  This  has  been  accounted  for  by  the  distribution  of  forests, 
"which  are  extensive  in  the  province  of  Constantine,  less  so  in  that  of  Algiers, 
and  have  all  but  disappeared  in  Oran. 

Most  of  the  winds,  as  has  been  stated,  are  northerly  and  westerly,  but  the 
Scirocco  or  S.E.  wind,  here  a  blast  from  the  desert,  occasionally  prevails,  and 
is  injurious  to  man  and  destructive  to  vegetation.  It  occurs  for  the  most  part 
between  June  and  October,  and  is  accompanied  by  great  heat.  The  mean 
annual  temperature  of  Algiers  is  G2°  F.  (Scoresby- Jackson),  the  temperature 
■of  the  three  winter  months  being  56°  F.  (Pietra  Santa),  and  that  of  the  rainy 
season  62°  F.  The  difference  between  winter  and  spring  mean  temperature 
is  small.  It  will  be  seen  that  the  climate  differs  from  the  climate  of  Egypt, 
being  far  moister  and,  rather  cooler,  and  with  regard  to  the  first  feature,  it 
presents  a  contrast  to  its  neighbour,  the  south-eastern  corner  of  Spain, 
which  is  often  arid  and  burnt  up  from  drought,  as  if  the  rainfall  of  this 
region  had  been  diverted  to  Algeria  in  the  manner  described  by  Dr.  Bennet. 

The  climate  of  Algeria  is  milder  and  moister  than  that  of  the  Eiviera,  and 
■occupies  an  intermediate  place  between  the  latter  and  that  of  Tangiers  in 
Morocco,  where  the  equalising  influence  of  the  Atlantic  is  more  felt  in  mode- 
rating extremes ;  but  the  great  advantage  which  Algeria  possesses  over  Egypt 
and  the  Eiviera  lies  in  the  number  and  variety  of  sanitaria  it  offers  to  invalids. 
Algiers  with  its  suburbs  offers  them  shelter  and  saline  breezes,  while  Blidah, 
Milianeh,  and  Medeah  are  excellent  mountain  stations,  and  the  desert  air  and 
cHmate  can  be  tried  at  Biskra  in  the  Sahara,  now  connected  to  Algiers  by 
railway. 

In  Algeria  we  can  witness,  too,  the  life  of  the  nomad  Arabs,  who  dwell  in 
tents  and  move  their  houses  and  flocks  according  to  the  season,  preferring 
the  plains  in  winter  and  the  mountains  in  summer.  Among  this  race  phthisis 
^nd  scrofula  are  unknown  ;  but  when  a  number  of  them  were  imprisoned  by 
the  French  Government,  fifty  per  cent,  died  of  phthisis. 

The  Algerian  climate  has  been  found  of  great  value  in  the  treatment  of 
^consumption,  and  the  writer  has  recorded  some  remarkable  cases  of  arrest 
under  its  influence. 

Tempeeate  Climates,  compeising  the  Eegions  between 
35°  AND  50°  Latitude 

This  division  includes  Central  and  Southern  Europe  with  its  islands,  the 
part  of  Asia  between  the  Mediterranean,  Black  Sea,  and  Japan,  a  great  part  of 
North  America  and  South  America,  south  of  Uruguay,  besides  the  Colony 
•of  Victoria  in  Austraha,  New  Zealand  and  Tasmania,  and  numerous  isles. 

The  mean  temperature  varies  from  50°  F.  to  60°  F.,  a  figure  made  up  of 
-considerable  extremes.  The  rainfall  also  varies  in  amount,  being  dependent 
on  the  proximity  to  the  sea  or  mountain  ranges.  The  four  seasons  are  well 
marked,  but  the  length  of  each  varies  considerably  accordingly  to  latitude. 
This  group  of  chmates  must  be  regarded  as  by  no  means  uniform  in  its 
features,  the  climate  of  each  region  approximating  in  meteorology  to  either 
the  warm  or  cold  groups  between  which  it  is  placed,  according  to  the  nearness 
of  either.    The  vast  inland  tracts  of  Central  Asia  and  British  North  America 


214  HYGIENE 

possess  a  very  difierent  climate  from  the  Genoese  Riviera  and  the  Atlantic 
coast  of  the  Spanish  Peninsula, 

The  inland  climates  of  Central  Europe,  Asia,  and  North  America  are 
characterised  hy  extremes  of  temperature,  as  is  shown  in  the  Canadian 
winter  and  summer,  and  hy  dryness  ;  whereas  in  the  countries  fringing  the 
sea  like  the  Atlantic  portions  of  France,  and  Spain,  and  Portugal,  these 
extremes  are  greatly  reduced,  and  the  rainfall  is  larger. 

The  temperate  climates  are  inhahited  by  the  most  vigorous  races  physicallj'' 
and  intellectually,  and  would  seem  to  have  been  in  all  ages  specially  favour- 
able to  the  growth  and  development  of  human  vigour  and  intellect,  as  shown 
by  the  example  of  Greece  and  Rome. 

Among  the  varieties  of  temperate  climates  is  to  be  named  that  of  the 
shores  of  the  Mediterranean  Sea,  as,  owing  to  the  shelter  from  northerly 
winds  afforded  by  the  mountain  ranges  to  the  north  of  it,  and  the  equalising 
influence  of  this  warm  body  of  water,  which  is  neither  cooled  by  glacier 
streams  nor  polar  currents,  and  which  undergoes  considerable  heating  from 
its  latitude,  the  north  shore,  and  especially  the  Genoese  Riviera,  enjoys  a 
very  favourable  climate,  in  which  both  extremes  are  considerably  tempered. 
This  is  most  marked  in  the  different  islands  of  the  Mediterranean,  such 
as,  among  others,  Malta,  Sicily,  Sardinia,  Corsica,  Crete,  Cyprus,  and  the 
Balearic  Isles.  The  summers  are  someAvhat  hot,  but  the  extremes  are 
considerably  modified  by  this  inland  sea. 

The  winter  climate  of  the  Riviera  is  warmer  than  that  of  the  British 
Isles,  by  at  least  3°  F.  It  is  dry  and  stimulating,  with  an  average  rainfall 
of  thirty-one  inches,^  and  the  average  number  of  rainy  days  is  sixty-five. 
The  winter  and  spring  months  are  comparatively  dry,  and  the  principal  rain- 
fall is  in  September,  October,  and  November.  It  exercises  a  highly  beneficial 
efiect  on  many  forms  of  chronic  disease,  chiefly  by  its  stimulating  influence,, 
and  in  the  treatment  of  phthisis  has  been  proved  to  be  of  the  greatest  utility,. 

The  statistics  of  the  hospitals  of  this  region  show  that  chronic  degenera- 
tive disease  is  rare,  while  acute  disease  is  common,  and  it  is  possible  that 
this  is  the  key  to  ihe  successful  treatment  of  chronic  disease  in  this  region, 
for  it  is  found  that  Avhereas  cases  of  chronic  bronchitis,  phthisis,  rheumatism,, 
and  kidney  disease,  improve  steadily  under  the  stimulating  influence,  various 
kmds  of  inflammations,  such  as  gastritis  and  enteritis,  and  afi'ections  of  the 
nervous  system,  especially  hysteria  and  insomnia,  are  rendered  worse  instead 
of  better.  Pyrexia  is  generally  augmented,  and  typhoid  fever  is  reported  to- 
run  a  more  protracted  course  than  in  the  North  of  Eiuope. 

Prevalent  Diseases 

These  are  for  the  most  part  the  ordinary  diseases  described  in  European 
and  American  text-books  of  medicine,  and  it  will  be  unnecessary  to 
recapitulate  them,  unless  there  be  any  which  can  be  fairly  attributed  to  the 
influence  of  climate. 

Rheumatism,  both  acute  and  chronic  pneumonia,  croupous  and  catarrhal, 
and  various  affections  of  the  air-passages  and  lungs,  prevail  largely  in 
temperate  climates,  and  may  be  fairly  attributed  to  the  vicissitudes  of  the 
weather,  especially  during  the  winter  months,  as  during  the  summer  there 
is  marked  diminution  in  the  mortality  from  these  causes.  On  the  other  hand, 
hay  fever,  a  disease  limited  to  temperate  climates,  prevails  only  in  summer, 
owing  to  the  presence  in  the  air  of  the  pollen  of  various  flowering  plants, 
which  enter  and  irritate  the  nasal  passages,  the  conjunctivae  of  the  eyes,  and 
the  larynx,  pharynx,  and  lungs,  the  active  symptoms  disappearing  on  the^ 

1  Symons,  Quarterly  Journal  of  the  Boyal  Meteorological  Society,  Jannaiy  1890. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  <2,\rj 

removal  of  the  sufferer  to  the  seaside,  or  at  the  close  of  the  pollen  season. 
This  troublesome,  though  not  dangerous  complaint,  prevails  in  Europe  and 
North  America  during  the  summer  months,  and  disappears  in  autumn. 

The  large  group  of  exanthemata,  and  other  fevers  that  prevail  in  tempe- 
rate climates,  are  due  to  the  action  of  organisms,  and  therefore  cannot  be 
attributed  to  climate,  except  in  a  secondary  sense,  as  fostering  their  growth. 
In  the  same  way  such  diseases  as  goitre  and  cretinism  are  attributable  to  local 
causes,  these  being  the  special  conformation  of  valleys,  peculiarities  of  soil,  or 
certain  mineral  salts  present  in  drinking  water,  or  again  individual  predis- 
position. These  diseases  cannot  be  assigned  to  general  climatic  influences, 
more  especially  as  they  are  found  to  prevail  under  such  opposite  conditions 
of  temperature  as  the  Soudan  in  Africa  and  British  North  America,  and  also 
both  in  dry  and  in  moist  climates. 

Many  diseases,  like  leprosy  and  pellagra,  have  been  referred  to  peculiarities 
of  diet,  which  has  been  proved  in  the  case  of  pellagra  in  Italy,  but  is  not  yet 
substantiated  with  regard  to  leprosy  ;  but  this  latter  disease,  prevailing  as 
it  does  under  the  most  varying  conditions  of  climate,  must  be  considered 
entirely  independent  of  this  factor. 

Pulmonary  consumption  cannot  be  said  to  be  the  special  production  of 
severe  climate,  though  doubtless  immunity  from  the  disease  has  been  shown 
to  exist  under  various  and  indeed  opposite  climatic  conditions. 

Cold  Climates 

This  division  embraces  a  large  area,  from  50"  N.  latitude  to  the  poles,  a 
great  portion  of  which  is  ocean,  or  else,  as  is  the  case  with  the  southern 
pole,  unknown  regions.  The  habitable  portions  are  in  the  northern  hemi- 
sphere and  include  the  North  of  Scotland,  Denmark,  Sweden  and  Norway, 
Iceland,  Finland  and  Lapland,  Northern  Eussia,  with  Spitzbergen  and 
Nova  Zembla,  Siberia  and  Kamschatka,  and  in  America,  part  of  British 
North  America  and  Greenland.  This  group  has  been  subdivided  into  a 
cold  region,  with  a  mean  temperature  between  50°  and  32°  F.,  and  a  glacial 
region  with  a  mean  below  the  freezing  point. 

The  temperature  falls  rapidly  between  latitudes  55°  and  75°,  and  the  fall 
amounts  to  22°  F.  to  27°  F.,  the  coldest  region  being  not  at  the  pole,  but  about 
10°  from  it  north  of  Behring's  Straits,  the  mean  temperature  there  ranging 
between  17°  F.  and  19°  F. 

As  is  well  known,  in  the  more  northerly  portion  the  sun  never  rises  above 
the  horizon  for  several  months  in  the  winter,  when  the  sky  is  illuminated  by 
the  aurora  borealis,  and  in  the  summer  for  several  months  the  sun  never 
sets.  During  this  season,  June  and  July,  the  temperature  rapidly  rises  to 
55°  F.,  to  60°  F.,  to  80°  F.,  or  even  90°'  F.,  and  rapid  development  of  the 
vegetation  and  growth  takes  place,  but  at  the  end  of  July  fogs  and 
rain  appear  and  are  soon  succeeded  by  snow  and  frost,  and  the  long  winter 
again  recommences,  during  which  there  is  scarcely  any  diurnal  variation 
of  temperature.  The  winds  seem  chiefly  N.E.  and  S.W.,  and  their  rapid 
changes  give  rise  to  tempests.  The  rainfall,  generally  in  the  form  of 
snow,  only  amounts  to  a  few  inches.  This  description  does  not  apply  to  the 
whole  of  the  cold  region,  but  to  the  northern  part  of  it,  whereas  the  portion 
abutting  on  the  temperate  zone  partakes  of  that  climate.  The  inhabitants 
of  cold  regions  are,  as  a  rule,  a  vigorous  race,  possibly  from  the  severe 
battle  of  life  they  must  fight  to  maintain  existence,  and  their  diseases  may 
be  generally  traced  to  either  defects  in  their  dietary  or  their  overcrowding 
in  small  and  ill-ventilated  huts.  Scurvy  and  scrofula  are  the  principal 
diseases,  the  former  arising  from  a  deficient  supply  of  vegetables  and  fruit, 


216 


HYGIENE 


and  the  latter  from  the  overcrowding  and  want  of  a  proper  supply  of  food 
generally.  Ophthalmia  and  amaurosis  are  also  reported  to  be  present, 
from  the  reflection  of  light  from  the  snow  in  the  polar  regions.  As 
physicians,  we  have  little  to  do  with  this  class  of  climates,  but  we  must  not 
forget  that  dry  cold,  which  is  the  feature  of  this  group,  has  a  bracing  efifect 
on  the  human  system,  unproves  the  appetite,  promotes  the  performance  of 
a  large  amount  of  muscular  work,  and,  as  it  is  fatal  to  all  germs,  is  a  good 
antiseptic. 

Makine  Climates 

are  characterised  chiefly  by  marine  mfluence,  and  especially  by  the  presence 
of  warm  sea  currents,  the  regions  included  being  capes,  islands,  peninsulas, 
and  promontories  washed  by  the  ocean  or  salt  seas,  which  by  their  warmth 
and  equalising  influence  raise  the  mean  temperature  of  the  adjacent  regions, 
and  at  the  same  time  temper  the  extremes.  The  source  of  heat  being  a 
moist  one,  the  humidity  and  rainfall  are  increased,  and  add  a  certain  soft- 


40°      39' 


ness  to  the  atmosphere.  Such  is  the  climate  of  Great  Britain  and  Ireland, 
the  coasts  of  Norway  and  Iceland,  which  all,  from  their  relation  to  the 
equatorial  current  and  Gulf  Stream,  enjoy  a  far  milder,  though  moister, 
climate  than  they  would  experience  if  situated  at  the  same  latitude  in  the 
centre  of  Asia  or  of  North  America. 

The  British  chmate  may  be  taken  as  the  type  of  this  class,  as  it  certainly 


INFLUENCE   OF  CLIMATE   ON  HEALTH  2l7 

owes  its  mild  atmosphere  to  the  sea  encompassing  our  islands,  and  to  the 
warm  equatorial  current  and  the  winds  generated  by  it.  This  is  shown  in 
several  remarkable  ways.  First,  the  winter  temperatures  of  the  towns  on 
the  south  coast  are  higher  than  inland  places  at  no  great  distance  from  them 
(Tripe).  Second,  the  mean  winter  temperature  of  these  stations  decreases 
towards  the  east  of  the  British  Channel,  the  mean  winter  temperature  of 
Hastings  being  6°  F.  less  than  that  of  Torquay.  Third,  the  effect  on  the 
winter  isothermal  lines  of  Great  Britain  (see  woodcut).  In  August  the 
isotherms  (dotted  lines)  very  much  follow  the  lines  of  latitude,  the  east  coast 
of  England  being  slightly  warmer  than  the  western  coasts  of  England  and 
Ireland,  but  in  January  the  isotherms  (continuous  black  lines)  become  almost 
vertical,  the  isotherm  of  39°  F.  running  through  Shetland  and  the  islands 
off  the  west  coast  of  Scotland  to  Hastings,  while  that  of  40°  F.  passes 
through  the  Isle  of  Man,  Llandudno,  and  Portsmouth.  The  isotherm  of 
43°  F.  runs  through  the  extreme  south-west  of  Ireland,  through  Devonshire 
and  the  Channel  Islands.  Thus  the  power  of  the  sun  being  weakened  in 
winter,  the  influence  of  the  equatorial  current  is  more  sharply  shown,  and 
we  see  what  a  valuable  warming  agent  it  proves  to  us  in  winter.  Fourth,  in 
the  increase  in  the  rainfall.  This  is  much  greater  on  the  western  coasts 
of  England  and  Scotland,  which  are  strongly  under  the  influence  of  the 
equatorial  current,  than  on  the  east  coast,  which  is  less  so.  The  rainfall  of 
the  west  coast  varies  from  60  to  80  inches,  and  that  of  the  east  coast  is  20 
inches,  and  on  the  east  coast  the  extremes  of  temperature  are  also  more 
marked.  The  characteristics  of  the  British  climate  are  absence  of  extremes, 
great  humidity,  and  great  variability  and  absence  of  sunshine.  The  result 
is  to  be  seen  in  a  vigorous  race,  liable  to  various  diseases  arising  partly  from 
vicissitudes  of  climate  themselves,  and  partly  from  confinement  within  doors 
which  these,  to  some  extent,  render  necessary.  The  good  complexions  of 
the  British,  and  especially  of  the  women,  are  due  to  the  protection  from 
sunburning  which  the  moist  vaporous  atmosphere  affords. 

The  principal  diseases  due  to  chmate  are  those  affecting  the  lungs  and 
air-passages — such  as  asthma,  bronchitis,  pharyngitis,  laryngitis,  pleurisy, 
pneumonia  and  phthisis,  rheumatism  and  its  sequelae,  and  various  forms  of 
kidney  disease ;  the  greater  part  of  which  may  be  attributed  to  the  dampness 
of  the  climate  and  the  constant  changes  in  the  weather. 

Eheumatism  and  bronchitis  prevail  most  in  the  winter  months,  and, 
according  to  Scoresby-Jackson,  a  low  mean  temperature  during  the  winter 
months  gives  rise  to  an  increase  in  the  death-rate  from  phthisis  and 
bronchitis,  and  this  relationship  is  more  clearly  to  be  observed  if  the  low 
temperature  be  sustained  for  some  months  without  intermission. 

Phthisis  prevails  all  the  year  round  in  England,  and  it  has  been  demon- 
strated to  bear  a  distinct  relationship  to  dampness  and  impermeability  of  soil, 
its  connection  with  particular  districts  depending  apparently  more  on  this 
feature  than  on  the  meteorology,  though  the  great  variability  of  this  latter 
exercises  some  influence. 

In  the  last  forty  years  the  death-rate  from  phthisis  in  the  United  Kiag- 
dom  has  diminished  to  half,  principally  from  the  more  efficient  soil  drainage 
and  the  various  measures  enforced  by  the  Legislature  to  improve  the  health 
of  the  working  classes. 

Nevertheless,  the  fact  of  the  great  prevalence  in  Great  Britain  and  Ire- 
land, and  its  rarity  in  many  dry  countries,  points  to  some  favouring  influence 
to  the  development  of  phthisis  in  the  climate  of  this  part  of  the  world  which 
must  be  partly  ascribed  to  its  elements  of  damp  and  frequent  change.     With 


218  HYGIENE 

reference  to  the  treatment  of  phthisis,  the  writer's  statistics '  of  243  patients 
treated  at  the  various  health  resorts  on  the  south  coast  showed  conclusively 
that  the  more  easterly  the  station  the  greater  the  amount  of  local  and  general 
improvement  to  be  derived,  and  that,  for  instance,  Hastings  gave  far  better 
results  than  Torquay  or  Penzance,  and  that  Bournemouth  and  Ventnor 
occupied  a  position  intermediate  between  these  in  improvement  of  patients. 

Sea  Voyages 

The  subject  of  the  climate  of  the  sea  falls  naturally  under  the  heading 
of  Marine  Climate,  and  we  here  propose  briefly  to  consider  the  question  of 
sea  voyages  in  their  relation  to  health.  Eattray's  -  important  observations  on 
the  crews  of  various  ships  of  the  Koyal  Navy  during  voyages  in  different 
climates,  show  that  life  at  sea  is  by  no  means  an  unmixed  blessing,  and  that 
the  tropics  should  be  avoided  by  the  natives  of  colder  and  temperate 
climates,  especially  by  the  young,  as  also  by  weakly  patients  or  those  sujBfer- 
ing  from  chronic  disease.  Eattray  also  shows  that  healthy  adults  should 
not  remain  too  long  in  tropical  climates,  and  should  leave  them  at  once 
if  strength  and  flesh  begin  to  fail ;  and  that  the  avoidance  of  other  weaken- 
ing influences,  such  as  a  faulty  diet,  over-fatigue,  and  impure  air,  which  are 
not  uncommon  cojicomitants  of  a  seaman's  life  in  the  tropics,  is  absolutely 
necessary  to  preserve  health.  The  most  striking  result  of  Eattray's  obser- 
vations was  the  loss  of  weight  by  able-bodied  seamen  under  the  combina- 
tion of  the  tropics  and  salt  diet,  which  occurred  in  81*55  per  cent.,  each 
losing,  on  an  average,  4  lbs.  When  muscular  exertion  was  added,  the 
percentage  of  losers  exceeded  91  per  cent.,  who,  in  104  days,  lost,  on  an 
average,  7  lbs.,  the  ship  boys  not  losing  so  much  as  the  men.  Eattray  also 
comments  on  the  wonderful  improvement  always  noted  when  the  crews 
reached  temperate  climates,  so  that  he  sums  up  with  the  conclusion  that,  to 
preserve  health,  a  tropical  climate  should  be  frequently  changed  for  the  more 
temperate  ones  of  the  higher  altitudes  or  latitudes. 

Eattray's  careful  observations  on  the  crews  show  that  in  the  tropics  the 
mine  decreases  from  69^  per  cent,  to  42  per  cent.,  and  that  the  perspiration 
increases  from  8^  per  cent,  to  30  per  cent.  There  was  a  diminution  of  4^ 
per  cent,  in  the  fluid  exhaled  by  the  lungs,  and  a  slight  increase  in  that 
secreted  from  the  bowels.  The  kidneys  appeared  to  be  the  principal  elimi- 
nators of  surplus  water,  both  in  the  tropics  and  in  temperate  climates,  but  the 
skin  was  most  worked  in  the  tropics  and  the  lungs  in  the  temperate  climes. 

It  is  evident,  then,  that  for  sea  voyages  to  be  profitable,  a  long  sojourn 
in  the  tropics  must  be  avoided  ;  and  this  has  greater  bearing  on  invalids 
than  on  healthy  people.  The  writer's^  statistics  of  a  number  of  consump- 
tives who  took  sea  voyages  to  the  Cape  and  Australia  were  very  favourable, 
but  it  should  be  stated  that  by  far  the  larger  proportion  of  these  patients 
(72  per  cent)  were  in  the  stage  of  lung  tuberculisation,  and  but  few  had 
cavities.  In  28  per  cent,  both  lungs  were  affected ;  89  per  cent,  of  these 
patients  improved ;  5^  per  cent,  remained  stationary,  and  5.V  per  cent, 
deteriorated.  Most  of  these  patients  undertook  the  voyage  to  Australia 
round  the  Cape  of  Good  Hope  in  clipper  ships,  not  steamers,  and  returned 
either  by  the  same  route  or  by  Cape  Horn.  Some  years  ago,  being  anxious 
to  ascertain  the  exact  climatic  conditions  of  voyages,  with  the  help  of  his 
friend,  Captain  Toynbee,  of  the  Meteorological  Office,  the  writer  consulted 

'  Lettsonian  Lectures.  "  Proceedings  of  Royal  Society,  1869-72. 

'  Influence  of  Climate  on  Consumption,  p.  99. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  219 

the  logs  of  the  various  sailmg  vessels  bound  to  Australia  or  New  Zealand,  at 
different  times  of  the  year,  and  extracted  such  portions  of  their  meteorology 
as  seemed  hkely  to  prove  useful  to  invalids. 

When  a  ship  leaves  England  in  October,  the  temperature  ranges  from 
52°  F.  to  58°  F.  for  the  first  five  days.  Off  the  Azores  it  rises  to  00°  F.,  and 
on  passing  the  Canaries  it  reaches  70°  F.  On  the  vessel  crossing  the 
equator  the  maximum  80°  F.  is  attained,  but  this  is  greatly  tempered  by 
breezes,  as  a  rule.  Afterwards  the  temperature  gradually  falls,  and  in  39  S. 
latitude  70°  F.  is  the  average,  and  this  sinks  to  00°  F.  on  reaching  the  Cape 
of  Good  Hope. 

After  rounding  the  Cape,  the  temperature,  owing  to  the  mixture  of  the 
warm  Agulhas  current,  with  cold  currents  from  the  Antarctic  Circle,  becomes 
uncertain,  and  varies  from  49°-5  F.  to  00°  F.,  the  currents  overlapping  each 
other  and  causing  much  variation  of  temperature  in  the  superincumbent  at- 
mosphere. The  vessel  reaches  45°  S.  latitude  and  steers  eastwards,  the  ther- 
mometer ranging  between  40°  F.  and  50°  F.,  owing  to  the  nearness  of  the 
Antarctic  Circle.  When  70  E.  longitude  is  attained,  the  temperature  remains 
steadily  above  50°  F.,  and  rises  to  06°  F.  on  approaching  the  continent 
of  Australia.  Throughout  the  voyage  the  temperature  may  be  said  to  vary 
between  40°  F.  and  80°  F.  The  number  of  rainy  days  is  about  twenty.  The 
atmosphere  is  a  moist  one  ;  the  hygrometer  gives  an  average  of  2°  F.  to  5°  F. 
difference  between  the  bulbs,  which,  considering  the  high  temperature  of  some 
portion  of  the  route,  shows  considerable  humidity.  The  voyage,  when  com- 
menced in  May  and  ended  in  August,  does  not  differ  very  much  in  temperature 
from  that  commenced  in  October.  The  temperature  of  the  equator,  then,  is 
85°  F.,  but  the  other  records  are  much  the  same,  only  the  traveller  has  the 
disadvantage  of  landing  in  Australia  in  mid-winter.  The  return  voyage  from 
Australia  or  New  Zealand  to  England  is  seldom  by  the  Cape  of  Good  Hope, 
but  usually  round  Cape  Horn,  and  consequently  the  vessel's  course  is  further 
southward,  and  approaches  more  closely  to  the  Antarctic  Circle.  It  is  here 
that  low  temperatures  are  met  with,  and  the  thermometer,  which  was 
55°  F.  off  New  Zealand  (Welhngton)  in  April,  fell  to  below  40°  F.,  and  for 
28  days  the  temperature  ranged  between  a  few  degrees  below  40°  F.  and  a 
few  degrees  above  it,  with  a  south  wind  from  the  Antarctic  regions.  How- 
ever, in  40°  S.  latitude,  a  rise  to  50°  F.  takes  place,  and  off  Monte  Video  it  is 
70°  F.  and  80°  F.  at  the  equator,  and  England  is  reached  the  middle  of  July. 

The  Australian  or  New  Zealand  voyage  occupies  about  three  months  in 
a  clipper,  or  from  37  to  45  days  in  a  steamer,  the  former  being  preferable 
for  health  purposes.  According  to  Dr.  Maclaren,  the  first  influence  of  the 
outward  voyage  on  the  invalid  is  a  sedative  one,  but  on  approaching  the 
Cape,  the  cooling  atmosphere  and  the  fresh  breezes  exercise  a  tonic  eft^ect, 
and  improvement  of  appetite  and  gain  of  weight  take  place.  A  shortened 
edition  of  this  voyage  is  the  one  to  the  Cape  of  Good  Hope,  occupying  about 
three  weeks  in  a  steamer  ;  it  is  a  good  method  of  escaping  part  of  the 
British  winter,  as,  with  a  halt  at  Cape  Town  or  Wynberg,  it  occupies  about 
two  months. 

Other  winter  voyages  which  can  be  recommended  are  those  to  the  West 
Indies  by  the  Eoyal  Mail  Steam  Packet  Company's  steamers,  which  touch  at 
most  of  the  islands  and  several  of  the  ports  of  Central  America,  the  trip 
occupying  from  six  weeks  to  four  months,  spent  mostly  in  mild  regions  ;  but 
it  is  doubtful  whether  Eattray's  objections  to  long  sojourns  in  the  tropics  do 
not  apply  here,  and  this  voyage  would  not  be  advisable  for  the  young. 

Another  salutary  trip  is  the  Brazihan  voyage,  where  the  vessel  touches 
at  Lisbon,  Teneriffe,  Pernambuco,  Bahia,  Eio  de  Janeiro,  Monte  Video   and 


220  HYGIENE 

Buenos  Ayres,  and  occupies  two  to  three  months.  Here  temperate  climes 
are  intermingled  with  the  tropics  much  to  the  traveller's  benefit. 

Far  different  in  its  meteorology  and  in  its  results  on  invalids  is  the  voyage 
to  India  and  China,  through  the  Suez  Canal  and  Eed  Sea,  for  here  we  get' 
sudden  transitions  from  extremes  of  temperature,  which  are  most  pernicious. 
The  increased  heat  in  the  Suez  Canal  and  the  still  greater  rise  in  the  Red 
Sea,  where  the  thermometer  often  marks  98°  F.,  combined  with  great  dry- 
ness, the  wet  and  dry  bulbs  showing  a  difference  varying  from  8°  to  12°  F., 
acts  most  injuriously  on  the  appetite  and  strength  and  Hesh  of  patients,  and 
the  temperature  of  the  climate  of  the  Indian  Ocean  (79°  to  81°  F.)  is  too 
high  to  promote  health.  On  the  return  voyage,  too,  the  passing  from  the 
hot  atmosphere  of  the  Eed  Sea  into  the  cooler  ]\Iediterranean  climate, 
especially  if  the  Tramontana  be  blowing,  checks  perspiration  and  often 
induces  temporary  albuminuria.'  The  writer  has,  moreover,  known  more 
than  one  consumptive  perish  in  the  Eed  Sea  from  the  overpowering  influence 
of  heat,  inducing  diarrhoea ;  and  the  depressing  effect  on  constitutions 
already  weakened  by  disease  is  most  disastrous. 

Sea  voyages,  if  the  right  season  and  route  be  chosen,  are  productive  of 
much  good,  as  they  are  a  means  of  supplying  patients  with  abundant  fresh 
air  without  fatigue,  and  the  atmosphere  is  rich  in  ozone  and  free  from  dust 
and  germs.  As  long  as  the  weather  is  fine  and  the  invalid  lives,  and  even 
sleeps,  on  deck,  all  is  well,  but  when  bad  weather  confines  him  to  his  cabin, 
a  very  different  state  of  affairs  prevails,  for  he  may  be  doomed  to  imprison- 
ment in  what  in  his  own  house  he  would  designate  a  cupboard,  and  which, 
when  the  portholes  are  closed,  as  during  storms,  often  proves  a  very  ill-venti- 
lated one.  Also  the  lack  of  proper  exercise,  except  walking  the  deck,  and 
occasionally  the  chance  of  running  short  of  provisions,  are  serious  drawbacks. 

Sea  voyages  have  proved  most  useful  in  checking  the  tendency  to  haemor- 
rhage, in  promoting  sleep,  and  are,  therefore,  very  beneficial  where  the  brain 
and  nervous  system  have  been  overworked,  and  in  checking  chronic  discharges, 
such  as  from  fistula,  strumous  abscesses,  and  old  ulcers,  and  in  assisting 
antiseptic  treatment.  The  appetite  is  greatly  stimulated  on  board  ship,  and, 
as  a  rule,  the  larder  is  well  supplied,  and  consequently  food  is  consumed  in 
abundance,  and  large  gain  of  weight,  often  amounting  to  one  or  two  stone, 
follows.  Sometimes  too  great  indulgence  is  given  to  the  appetite,  and  this 
excess,  combined  with  want  of  exercise,  promotes  biliousness  and  dyspepsia, 
which  are  by  no  means  rare  on  board  ship.  Often  another  bad  practice 
springs  up  on  board — viz.  drinking,  in  most  cases  pursued  through  want  of 
occupation,  and  this  often  ruins  the  prospects  of  an  otherwise  promising 
patient. 

Mountain  Climates 

This  division  is  characterised  by  diminished  barometric  pressure,  increased 
diathermancy,  and  by  great  extremes  of  temperature.  So  many  of  the  lead- 
ing features  of  these  climates  have  been  alluded  to  already,  that  it  will  not 
be  necessary  to  treat  of  them  as  fully  as  has  been  done  in  the  case  of  the 
other  four  groups,  but  we  must  say  a  word  on  some  of  their  striking  qualities. 
In  addition  to  being  distinguished  by  rarefaction  and  diathermancy  of  atmo- 
sphere, they  are  strongly  aseptic,  and  this  is  shown  by  the  long  period  that 
meat  keeps  in  the  mountains  before  undergoing  decomposition.     They  are 

'  An  intelligent  surgeon  in  the  service  of  the  Peninsular  and  Oriental  Company  informed 
me  that,  on  testing  the  urine  of  the  healthy  passengers  after  entering  the  Mediterranean 
from  the  Canal,  he  found  albumen  in  all. 


INFLUENCE   OF  CLIMATE   ON  HEALTH  221 

also  very  dry,  especially  during  the  winter  months,  though  this  is  partly  due 
to  air  at  a  low  temperature  being  incapable  of  holding  moisture  in  suspension. 
Absorption  of  atmospheric  oxygen  by  the  blood  takes  place  more  readily, 
while,  at  the  same  time,  the  carbonic  acid  formed  within  the  body  passes  out- 
ward through  the  pulmonary  tissue  into  the  air,  which  is  inhaled  with  a 
greater  degree  of  facility  than  at  lower  altitudes  (Marcet). 

One  of  the  greatest  arguments  in  favour  of  mountain  climates  is  the  well- 
known  immunity  from  the  greater  number  of  diseases  mountaineers  enjoy, 
and  the  general  vigour  of  body  that  they  possess.  When  we  contrast  them 
with  lowlanders,  the  comparison  is  almost  always  in  favour  of  the  former, 
who  are  generally  taller,  with  broader  and  deeper  chests,  and  greater  powers 
of  endurance,  especially  in  marching  and  walking ;  these  characteristics 
are  present  in  mountain  races  over  the  whole  globe,  be  they  the  natives  of 
the  Himalayas,  the  Indians  of  the  Andes,  the  chamois  hunters  of  the  Tyrol, 
the  guides  of  Switzerland  or  the  Highlanders  of  Scotland.  The  immunity 
from  phthisis,  which  has  been  so  strongly  insisted  on  by  Kuchenmeister  and 
others,  has  not  been  found  to  be  so  complete  as  he  has  set  forth,  nor  is  there 
any  fixed  immunity  altitude  for  each  degree  of  latitude,  as  he  would  infer, 
and  experience  has  shown  that  unhealthy  modes  of  life,  insufficient  food,  ill- 
ventilated  dwellings,  and  pernicious  habits  will  produce  phthisis  at  any  altitude 
or  in  any  latitude,  but  that,  if  these  are  avoided,  undoubtedly  an  altitude  of 
5,000  to  6,000  feet  above  sea-level  will  exercise  a  decidedly  protective  in- 
fluence against  phthisis,  even  in  those  predisposed  to  that  disease.  The  only 
diseases  which  the  mountain  climates  can  be  said  to  produce  are  the  so-called 
'  mal  des  montagnes,'  already  described,  and  a  form  of  dry  pleurisy,  known 
in  the  Alps  as  Alpenstick  ;  but  while  they  largely  benefit  phthisis  and  other 
strumous  affections,  they  are  injurious  and  consequently  contra-indicated 
in  the  following :  (1)  emphysema  ;  (2)  chronic  bronchitis  and  bronchiectasis ; 

(3)  diseases  of  the  heart  and  great  vessels,  of  the  kidneys,  and  of  the  liver  ; 

(4)  diseases  of  the  brain  and  spinal  cord,  and  all  states  of  hyper-sensibility 
of  the  nervous  system  ;  (5)  the  catarrhal  and  laryngeal  varieties  oi  phthisis, 
as  well  as  erethric  phthisis,  when  there  is  great  irritabihty  of  the  nervous 
system,  and  all  cases  of  advanced  disease  of  any  kind. 

On  the  other  hand,  the  benefit  of  moimtain  climates  is  immense  in  the 
following  :  (1)  cases  of  strong  hereditary  predisposition  in  which  phthisis  is 
either  threatened  or  is  in  a  state  of  early  development;  (2)  imperfect 
thoracic  or  pulmonary  development ;  (3)  hemorrhagic  phthisis ;  (4)  chronic 
tubercular  phthisis  in  its  various  stages,  provided  the  lung-surface  be  not  too 
largely  involved  to  admit  of  proper  aeration  at  high  altitudes,  and  there  be 
no  pyrexia  ;  (5)  chronic  pleurisy,  where  the  lung  does  not  expand  after  the 
removal  or  absorption  of  the  fluid,  and  chronic  pneumonia,  without  bronchi- 
ectasis, that  does  not  resolve  ;  (6)  anemia ;  (7)  and  spasmodic  asthma  with- 
out any  considerable  amount  of  emphysema. 

Another  point  to  bear  in  mind  is,  that  no  patient  should  attempt  high 
altitude  climates  who  cannot  take  exercise,  and  abundant  exercise,  and 
therefore  the  aged  and  very  feeble  are  clearly  debarred. 

Though  among  the  mountain  ranges  of  the  globe  we  have  plenty  of  choice 
of  elevation,  the  number  of  stations  suitable  in  the  way  of  height,  shelter, 
latitude,  and  accommodation  is  limited,  and  they  are  the  following : 

1.  The  Alpine,  varying  in  height  from  4,771  feet  to  6,000  feet,  with  a 
winter  mean  temperature  of  about  28' 1°  F.,  great  extremes  of  climate,  and 
fifty-two  rainy  or  snowy  days ;  the  principal  stations  being  St.  Moritz 
(6,090  feet),  Davos  (5,200  feet),  Maloja  (5,941  feet),  Wiesen  (4,770  feet),  and 
Andermatt  (4,738  feet),  in  Switzerland.     The  winter  climate  is  very  cold, 


222  HYGIENE 

dry,  and  calm,  but  the  sun's  rays  are  most  powerful,  as  sllO^\1lby  the  tamiing 
of  the  skiu. 

2.  The  Rocliy  Mountains  sanitaria  of  North  America,  varying  in  altitude 
from  5,200  to  9,000  feet,  the  climate  resembling  that  of  the  Alpine  resorts, 
but  warmer,  drier,  and  with  less  snow,  but  more  dust.  The  stations  in 
Colorado  are  Denver  (5,200  feet),  Colorado  Springs  (0,000  feet),  Manitou 
Springs  (6,370  feet)  Poncha  Springs  (9,000  feet),  Waggon  Wheel  Gap 
(9,000  feet),  Elkhorn  (7,500  feet).  Palmer  Lake  (7,2R8  feet),  Yellowstone 
National  Park  (0,000  feet),  and  Santa  Fe  (7,013  feet),  Silver  City  (5,890  feet), 
and  Mesilla  Valley  (4,000  to  7,000  feet),  in  New  ]\Iexico. 

3.  The  sanitaria  of  the  Andes,  of  altitudes  varying  from  8,000  to  13,500 
feet,  and  owing  to  more  southern  latitude  enjoying  warmer  and  more  equable 
climates  than  the  above  and  in  many  cases  a  mean  temperature  of  00''  F.  at  all 
seasons  :  Santa  Fe  di  Bogota  (9,000  feet),  in  New  Granada  ;  Quito  (10,000 
feet),  Equador  ;  Jauja  (18,000  feet),  Tarma  (10,028  feet),  and  Huancayo 
(10,718  feet),  in  Peru  ;  La  Paz  (18,500  feet),  in  Bolivia.  Chmate  generally 
dry,  warm,  and  bracing,  except  at  La  Paz,  where  the  winter  is  cold. 

4.  Himalaya  and  other  mountain  stations,  of  altitudes  varying  from  3,000 
feet  to  8,000  feet.  Himalayan  4,000  feet  to  8,000  feet.  Eainfall  70  to  132 
inches.  Mean  temperature  00°  to  70°  F.  Darjeehng,  Simla,  Landour,  and 
Nynee  Tal,  Nilghiri  sanitaria,  with  an  altitude  of  from  5,000  to  7,000  feet, 
mean  temperature  from  54°  to  70°  F.,  and  rainfall  from  50  to  60  inches. 
The  climate  is  cool,  but  subject  to  considerable  extremes,  and  damp  owing  to 
the  excessive  rainfall. 

5.  The  South  African  Highlands  of  Cape  Colony,  Orange  Free  State,  and 
Transvaal,  containing  various  stations  of  altitudes  from  4,000  to  6,000  feet. 
Taking  Bloemfontein  as  a  type,  the  climate  is  warm,  with  seldom  any  extreme 
of  cold  even  in  winter,  and  delicate  persons  sleep  in  the  open  all  the  year 
round,  except  during  the  rainy  season  and  a  few  days  of  winter.  The  average 
minimum  is  55°  F.,  the  average  maximum  for  the  six  hot  months  82°  F., 
the  humidity  55  per  cent.,  the  rainfall  seventeen  inches,  and  the  number  of 
rainy  days  seventy.  Li  the  Karoo  districts  of  the  Cape  we  have  as  suitable 
stations  for  invalids  Aliwal  North  (4,848  feet),  Turkestan  (4,280  feet), 
Dordrecht  (5,200  feet),  and  Burghersdorft  (4,650  feet)  ;  in  the  Orange  Free 
State,  Bloemfontein  (4,540  feet) ;  and  in  the  Transvaal,  Pretoria  (4,007  feet), 
and  Johannesburg  (5,000  feet).  In  South  Africa  it  is  not  only  the  splendid 
chmate  which  benefits  the  visitors,  but  the  mode  of  life  pursued  by  most 
of  them  :  i.e.  living  on  the  trek  in  a  waggon,  shooting  their  food-supply  by 
day,  and  sleeping  in  the  open  at  night. 

Though  these  groups  vary  considerably  in  climate  as  regards  temperature 
and  moisture,  they  all  agree  in  the  reduction  of  the  barometric  pressure,  and 
this  is  the  essential  feature  of  the  whole  series,  and  the  use  of  them  in  the 
treatment  of  different  forms  of  chronic  disease  has  produced  most  astonishing 
and  beneficial  results,  which  will  probably  increase  as  the  number  of  high 
altitude  sanitaria  are  multiplied.  In  the  treatment  of  consumption,  the  writer 
has  shoAvn  from  his  statistics  that  out  of  141  cases  of  phthisis  thus  treated 
74-82  per  cent,  improved,  and  among  these  arrest  of  the  disease  took  place 
in  44  per  cent.,  and  deterioration  in  only  21^  per  cent. 

The  statistics  of  Dr.  Hermann  Weber  and  Dr.  Denison  (of  Colorado) 
confirm  this  conclusion. 


WATER 


BY 


THOMAS    STEVENSON,  M.D.,  and  F.R.C.P.  (Loxd.) 


WATEE 

Water  is  one  of  the  prime  necessaries  of  life,  and  ranlcs  next  to  air  in  the 
influence  which  it  exercises  upon  the  processes  of  animal  life.  Some 
physicians  would,  indeed,  contend  that  morbific  influences  are  more  often 
conveyed  through  the  instrumentality  of  water  than  by  the  atmosphere.  An 
adequate  knowledge  of  the  properties  of  water  in  its  various  physical  states 
of  solid,  liquid,  and  vapour,  and  especially  of  its  solvent  action  on  gases  and 
on  saline  bodies,  is  all-important  to  the  health  officer ;  to  whom  also  the 
impurities  present  in  natural  water-supplies  are  matters  of  the  greatest  prac- 
tical interest.  Our  existing  knowledge  of  the  eflects  of  these  impurities 
upon  human  beings  is  considerable,  though  still  very  imperfect ;  but  the 
means  at  our  disposal  for  detecting,  quantitatively  estimating,  and  appraising 
at  their  proper  value  such  impurities,  in  spite  of  the  numerous  and  extended 
published  researches  of  chemists  and  biologists,  are  comparatively  limited. 
Yet  when  we  contrast  the  knowledge  which  we  possess,  in  this  respect,  of 
water  with  that  of  the  atmosphere  and  the  soil,  it  may  safely  be  asserted  that 
we  have  as  complete  information  respecting  the  composition  and  properties 
of  the  constituents  of  our  domestic  water-supplies  as  we  have  of  the  air  we 
breathe,  and  of  the  soil  on  which  we  dwell.  We  may  soon  expect,  moreover, 
to  be  in  the  possession  of  fuller  knowledge  of  the  bacteriology  of  water- 
supplies — a  branch  of  science  inseparably  associated  with  the  bacteriology  of 
the  atmosphere  and  the  soil.  From  the  study  of  the  minute  organisms 
habitually  and  occasionally  present  in  air,  water,  and  soil,  it  may  be  expected 
that  great  advances  in  sanitary  science  will  accrue. 

To  the  chemist,  water,  long  believed  to  be  an  element  or  simple  substance, 
is  now  known  to  be  a  compound  of  oxygen  and  hydrogen,  in  the  proportions 
of  eight  parts  by  weight  of  oxygen  to  one  part  of  hydrogen.  Below  0°  C. 
(32°  F.)  it  forms  a  sohd  body  (ice) ;  above  100°  C.  (212°  F.),  under  the  ordi- 
nary barometric  pressure  of  30  inches,  or  760  millimetres  nearly,  it  exists  as 
a  gas  (steam) ;  whilst  at  all  intermediate  temperatures  it  forms  the  liquid, 
water,  ^ar  excellence.  During  its  passage  from  the  hquid  to  the  sohd  state — 
i.e.  during  the  act  of  freezing,  at  32°  F. — water  suddenly  expands  to  the  extent 
of  8^  per  cent,  of  its  hquid  volume,  so  that  ice  at  its  melting  point  is  specifi- 
cally lighter  than  water  at  the  same  temperature  (water  at  its  freezing 
point),  floats  upon  it,  and  has  the  specific  gravity  0'9168  when  compared  with 
water  at  the  same  temperature.  Water  in  freezing  gives  off  a  large  amount 
of  heat,  which  is  again  absorbed  or  becomes  '  latent '  during  the  subsequent 
liquefaction  of  ice  ;  and  these  absorptions  and  emissions  of  heat  durmg  thaw- 
ing and  freezing  play  a  great  part  in  tempering  the  severities  of  climate,  and 
in  preventing  the  otherwise  sudden  destructive  changes  in  the  temperature  of 
the  atmosphere  which  would  otherwise  ensue. 

Another  important  physical  property  of  water  is  its  anomalous  expansion 

whilst  undergoing  changes  of  temperature.     Water  whilst  passing  from  its 

freezing  to  its  boiling  temperature  at  first  contracts  until  the  temperature 

of  4°C.  (39°*2  Fahr.)  is  reached;  and  this  is  the  temperatm'e  at  which  the 

VOL.   I.  Q 


226  HYGIENE 

liquid  attains  its  maximum  density.  Above  4°  C,  it  expands  with  rise  of 
temperature  until  its  boiling  point  is  reached.  The  important  bearing  of  this 
anomalous  expansion  is,  that  when  a  mass  of  water — e.g.  that  in  a  pond — is 
cooled  by  radiation  at  its  surface,  the  cooler  surface  water  becomes  denser 
than  the  warmer  water  beneath,  and  hence  sinks  until  the  whole  mass  of  water 
is  cooled  down  to  4°  C.  (39°-2  Fahr.)  nadiation  still  going  on,  the  surface 
water  now  cooled  below  4°,  no  longer  sinks,  but  being  specifically  lighter 
than  the  warmer  water  beneath  remains  on  the  surface,  till,  the  freezing 
point  being  attained,  the  liquid  freezes,  and  the  solid  crust  of  ice  formed  in 
a  measure  protects  the  water  beneath  from  the  influence  of  cooling  currents 
of  air.  This  fi-eezing  of  deep  masses  of  water  at  the  surface,  and  the  main- 
tenance of  the  subjacent  water  in  winter  at  a  temperature  approxunating 
lo  39°  Fahr.,  serves  to  maintain  the  processes  of  animal  life  in  the  aquatic 
organisms  met  with  in  ponds,  lakes,  and  reservoirs  of  water  generally. 

The  disintegrating  action  of  water  upon  rocks  and  soils  is  largely  due  to 
the  irresistible  expansive  force  exerted  by  water  during  its  solidification  ;  for 
in  this  process,  as  has  been  already  stated,  water  expands  by  about  one 
twelfth  of  its  bulk,  and  the  ice  formed  is  practically  incompressible.  Hence 
the  hardest  rocks  are  rent  asunder  by  freezing  water.  A  familiar  instance 
of  the  force  exerted  by  water  during  its  solidification  is  seen  in  the  bursting 
durmg  a  frost  of  the  leaden  pipes  ordinarily  used  for  the  distribution  of 
domestic  water-supplies.  Thick  leaden  pipes  may  be  thus  ruptured  when 
the  freezing  water  lies  stagnant  withm  them  ;  and  when  a  thaw  sets  in,  the- 
plug  of  ice  which  has  filled  in  and  closed  the  rent  during  the  frost,  liquefies, 
and  the  resulting  leakage  at  once  reveals  what  has  happened. 

Water  boils  at  a  temperature  varying  with  the  atmospheric  pressure. 
When  tliis  is  normal,  i.e.  equal  to  the  pressure  of  a  column  of  mercury  of  30 
inches,  or  nearly  760  millimetres  in  height,  the  boiling  point  is  100°  C.  or 
212°  Fahr.  On  the  tops  of  mountains  where  the  pressure  is  less  than  30 
inches  of  mercury  the  boihng  point  is  lowered  ;  and  conversely  at  the  bottom 
of  deep  mines  the  boiling  point  is  appreciably  higher  than  100°  0. 

At  all  temperatures  above  its  boiling  point  water  forms  a  transparent,  colour- 
less, invisible  gas.  In  passing  from  the  liquid  to  the  gaseous  state,  it  absorbs 
a  large  amount  of  heat  without  becoming  hotter  (latent  heat  of  vaporisation) ; 
and  it  is  this  absorption  of  heat  which  causes  the  coohng  effect  of  the  evapor- 
ation of  surface  water  to  exert  an  important  influence  in  meteorology  and  in 
the  modification  of  climate.  The  great  specific  heat  of  water  as  compared 
with  other  liquids — i.e.  the  relatively  large  amount  of  heat  required  to  change 
its  temperature — has  also  a  most  beneficent  effect  in  preventing  sudden 
changes  of  temperature. 

Water  evaporates  at  all  temperatures,  and  the  evaporation  of  solid  water 
in  the  form  of  ice  and  snow  is  an  obvious  and  famihar  phenomenon.  The 
tension  of  water- vapour,  or  its  tendency  to  evaporate  at  any  given  tempera- 
ture is  treated  of  elsewhere  (see  Meteoeologt,  p.  164).  The  relative  satura- 
tion of  air  with  aqueous  vapour  is  termed  '  humidity  '  of  the  atmosphere,  and 
bears  no  direct  relation  to  the  quantity  of  aqueous  vapour  therein. 

The  atmosphere  forms  a  vast  storehouse  or  reservoir  for  water,  where  it 
for  the  most  part  exists  in  the  form  of  invisible  gas  or  vapour  ;  and  a  never 
ceasing  silent  process  of  distillation  is  going  on  around  us.  This  process^ 
effected  by  the  heat  of  the  sun's  rays,  is  unceasingly  providing  the  surface  of 
our  globe  with  fresh  and  pure  water,  which  again  is  as  constantly  becoming 
polluted  by  its  passage  over  and  through  organically  polluted  soils.  It  is 
commonly  stated  that  the  atmosphere  contains  a  variable  amount  of  aqueous 
vapour  '  dissolved '  in  it ;  but  it  would  perhaps  be  more  correct  to  say  that  the 


WATEB  227 

atmosphere  is  a  variable  mixture  of  the  gases,  oxygen,  nitrogen,  carbon  dioxide, 
and  water.  When  such  a  gaseous  mixture  is  cooled,  its  capacity  to  retain 
water  in  the  gaseous  state  is  diminished,  and  droplets  of  liquid  water  are 
deposited  on  cold  solid  bodies  in  the  form  of  dew.  In  other  words,  the 
vapour-tension  of  water  rises  with  increase  of  temperature. 

In  the  British  Isles  the  amount  of  aqueous  vapour  in  the  atmosphere  ranges 
from  two  grains  per  cubic  foot  of  air  in  winter  to  twelve  grains  in  summer,  or 
from  one  third  per  cent,  to  two  per  cent,  by  weight.  Our  atmosphere  is 
therefore,  as  has  been  already  stated,  a  huge  storehouse  into  which  pure  gaseous 
water  evaporates  under  the  heating  influence  of  the  sun's  rays,  to  be  again 
precipitated  as  rain,  hail,  or  snow  ;  and  thus  in  the  vast  laboratory  of  nature 
there  is  provision  for  a  constant  supply  of  pure  water.  Were  it  not  for  this 
unceasing  process  of  distillation,  our  water-supplies  would  speedily  become 
so  highly  charged  with  impurities  as  to  become  unfitted  for  the  maintenance 
of  animal  life. 

Water  is  the  most  universal  known  solvent.  It  dissolves,  or  retains,  all 
the  known  gases  ;  and  it  also  dissolves  or  takes  up  all  known  solid  bodies, 
except  perhaps  the' diamond  and  some  of  the  noble  metals.  Even  the  most 
refractory  minerals — commonly  termed  '  insoluble  ' — gradually  yield  to  the 
solvent  action  of  water,  an  action  often  greatly  aided  by  the  gases  dissolved 
in  all  natural  waters.  Thus,  for  example,  sulphate  of  barium  or  heavy  spar, 
one  of  the  most  insoluble  known  chemical  substances,  dissolves  in  water  to  the 
extent  of  one  part  in  four  hundred  thousand  parts  by  weight,  or  one  sixth  of 
a  grain  per  gallon.  It  is  in  this  way  that  rain-water  becomes  charged  with  the 
gaseous  constituents  of  the  atmosphere,  viz.  oxygen,  nitrogen,  and  carbon 
dioxide  gases  ;  and  to  a  less  extent  with  ammonium  nitrate  and  other  so- 
called  sohd  impurities.  Thus  also  water  in  flowing  over  and  percolating 
through  the  soil  takes  up  from  this,  or  dissolves,  additional  quantities  of  car- 
bonic acid,  since  the  soil  is  always  richer  in  this  gas  than  the  air  above  it : 
also  the  more  or  less  soluble  mineral  constituents  of  the  soil — notably  the 
carbonates  of  calcium  and  magnesium,  sulphates,  chloride  of  sodium,  and 
other  saline  matters.  Thus,  again,  streams  and  rivers  are  the  silent  conduits 
by  which  the  solid  crust  of  the  earth,  partly  dissolved  and  partly  in  a  state  of 
mechanical  suspension,  is  carried  seawards  and  there  deposited  in  the  form  of 
new  rocks,  or  retained  in  solution. 

Absolutely  pure  water,  in  the  chemical  sense  of  the  term,  is  a  substance 
of  extreme  rarity,  and  has  only  been  obtained  by  repeated  distillations  of 
fairly  pure  water  in  vessels  constructed  of  silver.  Water,  when  retained  in 
contact  with  surfaces  of  porcelain  or  glass,  quickly  takes  up  small  quantities 
of  solid  impurities  owing  to  its  solvent  action  upon  the  silicates  of  which  such 
vessels  are  constructed. 

In  the  following  pages  we  shall  have  to  treat  of  water,  not  in  its  che- 
mically pure,  but  in  its  natural  state  ;  and  in  speaking  of  a  pure  water,  the 
sanitarian  means  a  water  practically  free  from  noxious  gases,  from  injurious 
organic  matters,  from  injurious  metallic  constituents,  and  containing  no 
excess  of  mineral  ingredients,  albeit  charged  with  moderate  quantities  of 
ordinary  innocent  saline  matters,  and  well  aerated.  We  shall  consider  the 
sources  of  our  water-supplies ;  the  collection,  storage,  and  distribution  of 
water ;  its  impurities,  their  influence  on  health,  and  their  removal ;  the 
quantity  of  water  requisite  for  domestic  and  other  purposes  ;  the  means  at 
our  disposal  for  determining  its  purity  or  impurity ;  and  the  constituents 
generally  present  in  water.  The  permissible  limits  of  the  various  constituents 
and  impurities  of  potable  water-supplies  will  also  have  to  be  stated,  so  far 
as  existing  knowledge  permits  us  to  do  so . 

q2 


228  HYGIENE 


SOURCES   OF  WATER-SUPPLY 

The  sources  of  water-supply  are  very  varied  ;  but  they  may  be  classified 
as  follows,  each  clasi  of  water  having  its  own  special  characteristics.  All 
waters  are,  however,  as  has  been  already  stated,  idtimately  derived  from  that 
vast  mass  of  naturally  distilled  water  which  descends  through  the  atmo- 
sphere in  the  forms  of  mist,  dew,  rain,  hail,  and  snow.  In  addition  there  is 
water  artificially  distilled,  as  on  ship-board  and  in  tropical  regions,  ap- 
proximating in  its  characters  more  to  rain-water  than  to  any  other  natural 
water, 

I.  Bain-%oater,  which,  after  being  collected  on  the  roofs  of  buildings  and 
other  more  or  less  flat  surfaces,  is  stored  in  appropriate  receptacles.  This 
when  collected,  with  due  care,  on  clean  surfaces  in  country  districts,  is  in  one 
sense  the  purest  natural  water.  That  collected  in  and  near  towns  and 
factories  is  generally  too  impure  to  be  fit  for  drinking  purposes. 

II.  Upland  water,  or  surface  water,  which  having  fallen  on  a  sparsely 
populated  and  but  little  cultivated  soil  is  collected  in  ponds,  lakes,  or 
artificial  reservoirs,  and  stored  for  use.  Such  waters,  as  a  rule,  contain 
very  little  dissolved  saline  matter  ;  though  they  may  contain  a  good  deal 
of  dissolved  peaty  matter,  rendering  them  brown  in  colour  and  bitter  in 
taste. 

III.  Spring  and  ivell-zvaters.  Here  the  rain-water  has  percolated  to  a 
greater  or  less  depth  into  the  soil  and  subsoil,  and  is  by  the  pressure  or  '  head ' 
of  superjacent  water  in  the  soil  forced  to  the  surface  through  holes  and  fissures 
(spring- water)  or  into  holes  sunk  into  the  earth  (well-water).  Spring  and  well- 
waters  belong  practically  to  the  same  class.  They  vary  very  greatly  in  their 
composition,  according  to  the  nature  of  the  subsoil  whence  they  are  derived. 
Springs  and  deep  wells  usually  afford  hard,  sparkling  waters  ;  whilst  shallow 
wells  commonly  afford  bad  and  organically  impure  waters. 

IV.  Bivers  are  fed  by  surface  water,  waters  from  land  drainage,  and  by 
the  overflow  of  springs  :  hence  they  vary  greatly  in  composition  and  purity. 
Often  they  are  largely  contaminated  by  sewage.  As  a  rule  they  furnish 
waters  less  hard  and  saHne  than  the  average  of  spring  waters  feeding  them, 
part  of  the  chalk  of  the  springs  having  been  deposited  on  exposure  to  the 
air,  by  loss  of  carbonic  acid.  When  a  river  is  large,  its  water  generally  has 
a  pretty  uniform  composition,  except  during  times  of  flood.  This  is  well 
sho"ttm  in  the  water  of  the  Thames  at  the  intake  of  the  London  water  com- 
panies. This  water  does  not  materially  vary  in  the  amount  and  proportions 
of  its  various  saline  constituents  at  different  seasons  of  the  year.  But  it 
must  be  admitted  that  the  Thames  is  more  largely  derived  from  springs 
discharging  into  the  bed  of  the  river  than  is  the  case  with  the  majority 
of  British  rivers. 

RAIN-WATER 

Eain-water  varies  in  composition  according  as  it  is  collected  in  the  country 
or  in  towns,  but  is  never  pure  water.  It  invariably  contains,  besides  the 
gases  of  the  atmosphere,  nitrate  and  nitrite  of  ammonium,  solid  amorphous 
and  crystalline  particles  in  suspension,  and  minute  organisms.  That  of 
towns  contains  the  acids  generated  by  the  combustion  of  coal,  and  notably 
sulphuric  and  hydrochloric  acids.  The  aggregate  amount  of  these  two  acids, 
in  the  free  state,  may  reach  as  much  as  seven  grains  per  gallon  or  ten  parts 
per  100,000.  Eain-water  collected  near  the  sea,  and  even  many  miles  inland, 
contains  small  quantities  of  the  salts  present  in  sea-water.     Even  the  rain- 


WATEB  229' 

water  collected  in  Florence  was  found  by  Beclii  to  contain  0*28  grain  per 
gallon,  or  0-4  part  per  100,000,  of  solid  matter,  about  half  of  which  was 
organic  and  half  inorganic,  the  chief  portion  of  the  latter  being  sulphate  of 
calcium  and  choride  of  sodium.  (' Deutsch.  Chem.  Ges.  Ber.'  viii.  p.  103.) 
Bechi  also  determined  the  amount  of  ammonia  and  of  nitric  acid  in  the  rain- 
water falling  respectively  in  Florence,  and  at  Vallombrosa  in  the  Apennines, 
more  than  8,000  feet  above  the  sea-level.  At  Vallombrosa  the  ammonia 
was,  on  the  average,  0-03G  grain  per  gallon,  or  0*51  part  per  million  ;  whilst 
in  Florence  there  was  0'078  grain,  or  I'll  part  per  million.  In  Vallombrosa 
the  nitric  acid  was  0*041  grain  per  gallon,  or  0"58  part  per  million,  and  in 
Florence  0'083  grain  per  gallon  or  1-18  part  per  million.  Lawes  and 
Gilbert  found  the  average  aggregate  amount  of  combined  nitrogen  in  country 
rain-water,  as  ammonia,  nitrates,  and  nitrites,  to  be  nearly  0*07  grain  per 
gallon,  or  one  part  per  million. 

Eain-vpater  dissolves  at  the  ordinary  temperature  of  our  country  about 
20  c.c,  per  litre,  or  5*5  c.i.  per  gallon,  of  the  atmospheric  gases,  of  which 
about  7  c.c.  per  litre,  or  nearly  2  c.i.  per  gallon,  is  oxygen  ;  12*5  c.c.  per  litre, 
or  8*5  c.i.  per  gallon,  is  nitrogen  ;  and  0'5  c.c.  per  litre,  or  0*14  c.i.  per  gallon, 
is  carbon  dioxide  gas.  But  rain-water  is  rarely,  if  ever,  fully  saturated  with 
oxygen,  this  gas  being  in  part  appropriated  by  the  organic  matters  present 
in  the  water ;  so  that  the  oxygen  rarely  exceeds  1"75  c.i.  per  gallon  or  6*3 
c.c.  per  litre. 

The  following  may  be  taken  as  the  average  composition  of  rain-water 
collected  in  inland  districts  remote  from  towns  : — 

Grains  Parts 

per  gall.         per  100,000 

Saline  constituents 2-1  3"0 

Combined  nitrogen 0"07  O'l 

The  Eiver  Pollution  Commissioners  in  their  sixth  report,  issued  in  1874, 
give  the  following  as  the  gaseous  constituents  of  rain-water  : — 

c.i.  per  gall.  C.c.  per  litre 

Nitrogen 3-63  lB-08 

Oxygen 1-77  6-37 

Carbonic  acid 0^35  1-28 

Total  gases         .        .         .     5-75  20-73 

When  rain-water  has  to  be  collected  from  buildings  and  stored  for  drink- 
ing purposes,  special  precautions  must  be  taken  to  ensure  its  cleanliness  and 
freedom  from  metallic  compounds  and  from  organic  impurities.  For  this 
purpose  it  should  never  be  collected  from  surfaces  of  lead,  and  even  roofs 
covered  with  sheet  zinc  or  galvanised  iron  commmiicate  some  zinc  to  the 
water  collected  on  them.  Eoofs  covered  with  slate  afford  the  best  collect- 
ing surfaces  for  rain-water.  The  first  water  collected  after  dry  weather  is 
always  dirty,  polluted  with  the  excrement  of  birds,  and  contains  vegetable 
spores. 

Mr.  Charles  Gay  Eoberts  has  designed  a  very  ingenious  and  effective  sepa- 
rator (figs.  82  and  83)  (p.  280)  for  automatically  getting  rid  of  the  first  and 
dirty  rain-water  falling  after  drought. 

A  vertical  separator  is  used  where  a  single  stack  pipe  carries  the  water 
from  the  roof  to  the  tank. 

In  figs.  82  and  83,  the  front  of  the  vertical  separator  has  been  removed  to 
show  the  interior.  Fig.  82  shows  it  in  the  position  that  it  retains  when 
running  foul  water  into  the  waste  pipe  during  the  first  part  of  a  shower,  while 
the  roof  is  yet  dirty.  Fig.  83  represents  it  when  it  has  canted  and  has 
begun  to  run  pure  water  into  the  storage  tank,  after  the  roof  has  become 


230 


HYGIENE 


clean.  The  change  of  position  is  effected  by  the  gradual  accumulation  of  a 
small  portion  of  the  water  in  the  chamber  J  of  the  canter ;  when  the  water 
reaches  a  certain  height,  it  makes  the  left  side  heavier  than  the  right,  and 
the  canter  turns  a  little  on  the  pivot  m  that  supports  it,  so  that  the  water  is 
delivered  two  inches  further  to  the  right  than  it  was  before  ;  and  whereas  it 
at  first  ran  through  n  into  the  waste  pipe,  it  now  runs  through  o  into  the 
storage  tank. 

In  figs.  82  and  83,  A  A  are  strainers  removable  for  washing,  b  is  a  remov- 
able slide,  with  two  small  holes  to  regulate  the  fiow  of  sufficient  water  to  work 
the  canter,   c  is  a  sluice  to  be  adjusted  to  the  area  of  the  roof,    d  is  the  outlet 


FOUL 


Fk;.  82. — Section  of  vertical  separator 
iini^ure  water  passing  to  waste. 


FOUL. 

FiG.  83. — Section  of  vertical  separator: 
pure  water  passing  to  storage. 


for  surplus  water.  In  moderately  heavy  rain  the  main  volume  of  the  water 
flows  through  this  spout  d  into  the  deli-s^ry  pipe  e,  rumiing  round  the  right 
hand  of  the  canter  ;  a  small  proportion  only  passes  through  the  strainer  and 
out  of  the  small  holes  b  into  the  funnel  f  that  terminates  in  the  small 
hole  G. 

In  a  very  slight  rain  the  whole  of  the  water  passes  through  the  strainers 
and  the  hole  at  b  into  f,  and  when  it  is  not  enough  to  effectually  wash  the 
roof  it  all  escapes  through  g  without  making  the  canter  move.  When  there 
is  more  rain  than  can  pass  through  the  hole  G,  it  rises  in  f  and  L,  and  a  small 
quantity  runs  over  the  side  of  the  funnel,  slowly  filling  the  chamber  j.  When 
J  is  filled  to  a  certain  height,  it  overbalances  the  canter  and  makes  the  water 
rmi  to  storage  through  o,  as  shown  in  fig.  83.   This  change  in  position  causes 


WATER  231 

the  water  from  b  to  run  into  t,  and  cease  to  run  into  f.  As  the  water  sinks 
in  F  it  also  sinks  in  l,  causing  the  siphon  k  to  act  and  empty  the  chamber  j. 
Meanwhile  some  of  the  water  from  t  will  have  been  running  through  the 
pipe  V  into  the  little  chamber  w,  and  the  weight  of  this  water  will  prevent 
the  canter  recanting  until  the  water  ceases  to  run  from  the  roof. 

As  soon  as  w  is  empty,  the  canter  rights  itself,  ready  for  the  next  rainfall, 
the  right-hand  side  of  the  canter  being  heavier  than  the  left  when  it  is  empty. 
By  means  of  the  joint  action  of  the  sluice  c  and  the  holes  at  B  and  g,  the 
flow  of  water  in  the  working  part  of  the  separator  is  so  regulated  that  the 
■chamber  j  is  filled  to  the  canting  point  as  soon  as  a  certain  quantity  of  rain 
has  fallen. 

One  of  the  chief  defects  of  a  rain-water  supply  is  its  scantiness  and  uncer- 
tainty. A  rainfall  of  25  inches  per  annum  is  equal  to  2,523  tons  per  acre,  or 
665,380  gallons  yearly ;  and  even  if  this  were  all  collected  and  stored  without 
loss,  it  would  suffice  for  62  persons  only,  each  person  being  allowed  25  gallons 
per  diem.  During  times  of  drought,  when  evaporation  is  usually  great,  it  is 
manifest  that  a  rain-water  supply  must  be  deficient,  except  where  only  a  small 
number  of  persons  has  to  be  supplied. 

In  Venice,  where  there  is  a  considerable  rainfall,  where  ordinary  wells  are 
impossible,  and  where  there  are  neither  roads,  nor  horses  or  other  draught 
animals,  and  where  all  the  circumstances  are  apparently  favourable,  the 
water-supply  for  drinking  purposes  was  until  recently  derived  from  rainfall. 
The  water  was  collected  from  all  available  gathering  areas  and  discharged 
into  underground  tanks  filled  with  sand.  The  water  was  thus  filtered  during 
its  passage  through  the  sand,  into  which  tubes  or  little  wells  with  impervious 
sides  are  sunk,  and  reach  nearly  to  the  bottom  of  the  sand.  The  water  was 
pumped  through  the  tubes  in  a  clear  condition.  This  system  is  one  of  down- 
ward filtration  of  a  simple,  and  it  is  said  of  effective  character. 

If  rain-water  is  to  be  used  for  drinking  purposes,  it  should  always  after 
collection  be  filtered  through  sand  and  charcoal,  or  other  equivalent  material, 
so  as  to  remove  suspended  matters,  before  storage  ;  and  should  then  be  kept 
for  some  time  in  carefully  covered  and  well-aired  tanks  or  cisterns,  lined  with 
slate  or  other  impervious  non-metallic  material.  A  good  plan  is  to  pass  the 
water  from  a  Eoberts'  separator  through  a  conduit  sufficiently  wide  to  con- 
siderably diminish  the  velocity  of  the  current,  and  over  a  catch-pit  which 
will  retain  the  grosser  suspended  particles.  The  conduit  should  then  make 
a  considerable  dip,  so  as  to  deliver  the  water  at  the  bottom  of  the  filter,  though 
it  should  pass  in  an  upward  direction  to  an  effluent  pipe  conveying  the  filtered 
water  into  a  covered  slate-lined  tank.  The  filter  may  consist  of  successive 
layers  of  coarse  sand ;  charcoal,  magnetic  carbide,  or  other  equivalent  puri- 
fying material ;  coarse  gravel ;  and  sand. 

"When  iron  tanks  and  pipes  are  used  for  the  storage  and  distribution  of 
xain-water,  the  metal  becomes  rapidly  corroded  ;  and  no  useful  purpose  appears 
to  be  served  by  coating  the  iron  with  zinc  (galvanising) ;  for  the  zinc  is  quickly 
removed,  and  the  water  becomes  turbid  with  zinc  compounds,  and  even 
contains  this  metal  in  solution.  This  zinc-caused  turbidity  persists  until  all 
the  coating  of  zinc  has  been  removed. 

The  following  approximately  correct  rules  are  useful  as  to  rainfaU,  and 
yield  of  rain  water  : — 

The  rainfall  in  the  wettest  year  is  double  that  of  the  driest  year. 

The  fall  in  the  wettest  year  is  one-third  more  than  the  average  rainfall. 

The  fall  in  the  driest  year  is  one-third  less  than  the  average  rainfaU. 


2^2  HYGIENE 


Upland  Waters 

Many  of  the  largo  nortlievn  manufacturing  towns  of  tliis  country,  such  as 
Glasgow,  Liverpool.  ^Manchester,  Leeds,  Sheffield,  and  Keighley,  are  supplied 
with  upland  water.  Glasgow  is  supplied  from  a  natural  reservoir — IjocIi 
Katrine.  The  new  Liverpool  supply  is  derived  from  a  gathering  ground  in 
Wales,  artificial  reservoirs  being  formed  for  its  storage.  The  usual  method  of 
obtaining  such  a  supply  is  to  impound  the  water  flowing  off  from  the  surface 
of  a  large,  barren,  uninhabited  area  of  land,  where  commonly  the  rainfall  is 
high,  and  the  amount  of  water  that  percolates  through  the  soil  small  as 
compared  with  that  which  flows  oft'  the  surface.  The  water  is  collected 
into  streamlets,  w^hich  combine  to  form  one  large  brook  at  the  bottom  of  a 
valley.  A  dam  is  built  across  this  at  a  convenient  spot,  and  the  water  is 
headed  back  into  the  reservoir  thus  formed.  Loch  Katrine  is  a  similar 
natural  reservoir  or  lake,  and  Lake  Thirlmere,  from  which  Manchester  is  to 
receive  its  new  water-supply,  is  also  a  similar  lake,  which  is  to  be  increased 
in  capacity,  and  its  level  raised  fifty  feet,  by  a  dam  built  across  one  end  of  it. 
The  natural  outlet  of  Lake  Thirlmere  is  to  the  north,  but  the  water  for 
]\Ianchester  is  to  be  obtained  by  tapping  the  southern  end  of  the  lake,  and 
drawing  oft'  the  necessary  quantity  of  water  by  means  of  a  tunnel  through 
Kirkdale  Pass.  In  dry  seasons  the  reservoirs  will  not  be  full.  In  flood- 
time  the  excess  of  water  flows  over  a  weir  at  a  fixed  height  into  a  '  bye  wash  ' 
or  side  channel,  and  thence  into  the  main  stream. 

The  probable  yield  of  a  gathering  ground  is  a  very  important  considera- 
tion, and  the  estimation  of  the  available  yield  of  water  from  a  given  area  is 
by  no  means  a  matter  of  easy  solution.  Mr.  Bateman's  views  as  to  the 
quantity  of  rainfall  available  for  water-supply  are  set  out  in  the  '  Report  of 
the  Eoyal  Commission  on  Water-Supply  (1809).'  Where  the  average  rainfall 
in  a  mountainous  district  is  75  inches,  he  estimates  that  80  per  cent,  of  that 
amount,  or  GO  inches,  may  be  taken  as  the  average  fall  of  two  or  three  con- 
secutive dry  years.  In  such  rainy  districts  the  loss  from  evaporation  and 
absorption  averages  from  9  to  16  inches,  and  he  adopts  12  inches  as  the 
mean  for  North  Wales.  This  12  inches  deducted  from  the  60  inches  above 
leaves  48  inches,  or  64  per  cent,  of  the  total  average  rainfall,_  as  the  net 
available  rainfall  Avlien  the  total  average  rainfall  is  75  inches.  But  for 
greater  security,  Mr.  Bateman  diminishes  again  the  last  result  by  25  per  cent, 
and  takes  36  inches  as  the  estimated  available  proportion  of  the  rainfall  of 
75  inches — i.e.  48  per  cent,  (or  practically  one-half),  on  which  to  base  his 
calculations.  In  the  old  Manchester  waterworks,  wdth  an  estimated  rainfall 
of  a  little  more  than  half  75  inches,  he  states  that  he  collected  32  inches 
of  rainfall. 

Other  eminent  authorities  think  Mr.  Bateman's  estimate  of  the  pro- 
portion of  available  supply  too  high.  Mr.  Thomas  Hawksley  says  it  is- 
kno^vn  to  be  impossible,  by  any  system  of  reservoirs  that  can  be  constructed, 
to  deal  with  more  than  the  average  of  three  consecutive  years  of  minimum 
fall.  The  minimum  year  has  about  one-third  less  than  the  general 
average  rainfall ;  and  in  the  three  consecutive  driest  years  the  average 
fall  is  almost  precisely  one-sixth  less.  Thus,  with  an  average  rainfall  of  45 
inches,  he  would  deduct  one -sixth,  leaving  37^  inches  as  the  average  quantity 
of  the  three  minimum  years,  and  in  a  district  partly  lowland  and  partly 
highland,  as,  e.g.,  in  North  Wales,  he  would  deduct  13  J,  inches  from  the  above 
37h  inches  for  loss  by  evaporation,  &c.,  leaving  24  inches  only  as  the  net 
available  rainfall,  where  45  inches  is  the  average  annual  fall — or  about  55 


WATER  235 

per  cent,  of  the  whole  rainfall  (op.  cii.).  The  experience  of  recent  years  has 
shoAvn  that  even  this  estimate  of  Mr.  Ilawksley's  of  net  available  rainfall  may 
sometimes  be  excessive. 

Sir  Eobert  Rawlinson  [op.  cit.)  considers  that  a  deduction  of  one-third 
should  be  made  from  the  average  to  arrive  at  the  minimum  rainfall  of  any 
one  year.  Mr.  J.  Gr.  Symons,  taking  the  true  mean  rainfall  of  a  wet  district 
(the  Lake  District)  as  77  inches,  infers  that  the  mean  of  three  dry  years 
would  be  80  per  cent,  of  this  amount,  or  61^  inches  ;  but  in  the  driest  years 
he  would  take  only  something  like  GG  to  G8  per  cent. — say  two-thirds — of  the 
average  as  the  true  dry  season  rainfall. 

In  this  connection  it  may  be  remarked  that  the  proportion  of  evaporation 
to  rainfall  is  very  variable,  and  that  the  data  afforded  by  observation  in  one 
country  or  locality  are  inapplicable  to  another  dissimilar  district,  or  to  a 
country  with  a  widely  different  climate.  Hence  the  recorded  results  of 
observations  made  are  widely  discrepant  and  irreconcilable.  Formerly  it  was 
held  by  French  hydraulic  engineers  that  evaporation  always  exceeds  rainfall 
(Geikie's  '  Text  Book  of  Geology,'  p.  3G0),  but  it  has  been  since  shown 
that,  except  in  unusually  dry  years,  rainfall  invariably  exceeds  evaporation. 
At  Lea  Bridge,  near  London,  the  average  recorded  rainfall  of  ten  years  was 
25*5  inches,  and  the  evaporation  from  the  surface  was  21  inches  per  annum 
(Symons's  *  Brit.  Eainfall  for  18G9,'  p.  162).  The  discharge  of  rivers,  as 
compared  with  rainfall,  varies,  of  course,  to  a  still  greater  extent  than  the 
proportion  of  evaporation  to  rainfall.  In  the  Thames  basin,  and  in  most  of 
the  river  basins  of  Great  Britain,  it  is  said  that  from  one-fourth  to  one-third 
of  the  rainfall  is  discharged  by  rivers.  The  Seine  at  Paris  is  stated  to  carry 
down  one-third  of  the  rainfall  of  its  basin,  and  the  Mississippi  is  also  stated 
to  discharge  one-fourth  of  the  rainfall  of  its  collecting  area,  whilst  the  Mis- 
souri discharges  only  one-sixth  of  the  rainfall  of  its  basin.  But  some 
American  rivers  are  computed  to  discharge  nine -tenths  of  the  rainfall  of  their 
respective  basins. 

Mr.  Symons  has  deduced  from  meteorological  returns  the  general  result 
that  in  any  given  district  the  wettest  year  of  a  series  will  have  in  the  British 
Isles  a  rainfall  nearly  half  as  much  again  as  the  mean  ;  that  the  driest  year 
will  have  one-third  less  fall  than  the  mean,  and  that  the  driest  three  consecu- 
tive years  will  each  have  one-fifth  less  than  the  mean  rauifall  of  a  long  series- 
of  years.     Now  let  R.m.  be  the  mean  average  rainfall,  then  we  have  : 

Eainfall  in  the  wettest  year     .....    1"5  E.m. 

,,  ,,       driest      ,, f  R.m. 

Mean  of  the  driest  three  consecutive  years       .         .     0-8  E.m. 

Thus,  if  Q  =  daily  quantity  in  gallons  for  all  purposes  required  to  be 
supplied  from  the  reservoir,  then,  E  being  inches  of  rainfall  evaporated, 
Q  =  62  A  (0-8  E.m.  -  E).' 

Which  gives  the  relation  between  the  area  of  the  gathering  ground  (A),  and 
the  quantity  it  will  supply  (Q),  and  by  substituting  150  Q  for  Q  in  wet,  and 
200  Q  for  Q  in  dry  districts,  we  arrive  at  the  storage  capacity  of  the  reser- 
voirs required  ('  Pole  on  Water-Supply,'  p.  24). 

Characteristics  of  Upland  Surface  Waters 
Upland  surface  waters  may  be  derived  from  either  igneous  or  metamorphic 
rocks  ;  but  the  analyses  made  for  the  Eiyers  Pollution  Commissioners  (6th 

'  Mr.  Pole's  factor  is  62-15.  According  to  the  new  deteiinination  (recently  legalised^ 
of  the  weight  of  a  cubic  inch  of  water  at  62°  F.  (252-286  grains)  the  factor  should  be  61-89.. 
I  have  adopted  62  as  sufficiently  exact.  [T.  S.] 


234  HYGIENE 

Eep.  1869)  show  that  the  upland  surface  waters  from  the  exposed  Metamor- 
phic,  Cambrian,  Sihirian,  and  Devonian  rocks  in  Great  Britain  do  not  differ 
materially  in  composition — except,  perhaps,  as  to  their  minuter  mineral 
constituents — from  those  derived  from  the  harder  igneous  rocks.  Their 
total  solid  constituents  were  found  to  range  from  about  1  to  9  grains  per 
gallon,  the  average  amount  being  3'5  grains.  They  are  pure,  soft  waters, 
not  infrequently  destitute  of  chalk  ;  and  they  sometimes  contain  free  acid  or 
acid  salts.  Organic  substances  are  present  in  small  quantity,  and  are  chiefly 
of  vegetable  origin.  These  waters  are,  however,  often  peaty,  bitter,  and 
highly  coloured ;  and  peaty  waters  are  prone  to  cause  temporary  diarrhoea 
Avhen  drunk  by  persons  unaccustomed  to  their  use.  They  also  dissolve  lead 
freely. 

The  upland  surface  waters  from  the  Yoredale  and  Millstone  Grits  and  the 
non-calcareous  portions  of  the  Coal  Measures  contain  rather  more  saline  con- 
stituents than  the  above-named  waters  ;  these  varying  from  about  3  to  10  or 
11  grains  per  gallon,  according  to  the  analyses  made  for  the  Eivers  Pollution 
Commissioners  ;  the  average  being,  however,  little  more  than  six  grains  per 
gallon.  Those  from  the  Lower  London  Tertiaries  and  Bagshot  beds  are 
still  more  saline  ;  whilst  those  from  the  calcareous  portions  of  the  Silurian 
and  Devonian  rocks  contain  from  8'5  to  10  grains  per  gallon  of  saline  solids. 
Those  from  the  calcareous  portions  of  the  Mountain  Limestone  contain  from 
8'o  to  16  grains  per  gallon  of  solid  matter,  and  are  of  moderate  hardness. 
The  surface  waters  from  the  calcareous  portions  of  the  Coal  Measures  may 
contain  as  much  as  38  grains  per  gallon  of  saline  matter,  with  an  average 
of  about  16  grains,  according  to  the  Eivers  Pollution  Commissioners  (op.  cit.), 
and  their  hardness  may  be  considerable.  The  upland  surface  waters  from 
the  Lias,  New  Eed  Sandstone,  Conglomerate  Sandstone,  Magnesian  Lime- 
stone, and  Oolite  formations  approximate  in  composition  to  those  from  the 
Mountain  Limestone. 

The  surface  waters  from  cultivated  land,  when  this  is  not  calcareous,  do 
not  appear  to  contain  much  more  solid  matter  than  those  from  upland  uncul- 
tivated soils,  according  to  the  Eivers  Pollution  Commissioners,  who  give  the 
average  amounts  as  4*5  and  6'5  grains  per  gallon  respectively.  It  is  chiefly 
the  organic  impurity  which,  as  might  be  expected,  is  increased  by  the  culti- 
vation and  manuring  of  the  soil.  Where,  however,  the  soil  under  cultiva- 
tion is  calcareous,  the  saline  constituents  of  the  surface  water  rarely  fall  below 
14  grains,  and  may  rise  to  nearly  80  grains  per  gallon. 

The  land  drainage  from  a  highly  manured  soil  usually  yields  an  im- 
pure water.  The  carbonic  acid  formed  during  the  decomposition  of  organic 
matters,  whether  animal  or  vegetable,  greatly  increases  the  solvent  action 
of  these  waters  upon  calcareous  matter. 

Water  stored  in  large  lakes  is,  as  a  rule,  potable,  safe,  and  little  liable 
to  serious  pollution  from  animal  matters  ;  but  that  from  very  small  lakes 
and  ponds  is  often  more  largely  contaminated,  since  the  proportion  of 
sewage  and  drainage  from  manured  land  is  great  in  proportion  to  the  volume 
of  the  effluent  water.  A  vexed  question  relates  to  the  decomposing 
vegetable  matter  and  the  organisms  of  pond  life  both  of  animal  and  vegetable 
nature,  usually  present.  The  minute  vegetable  organisms — often  invisible 
to  the  eye — present  in  such  waters  often  render  it  difficult  to  store  such 
waters  without  offence  ;  and  under  these  circumstances  such  waters  cannot 
be  considered  to  furnish  satisfactory  supplies.  These  waters  are  generally 
satisfactory  when  carefully  filtered ;  but  they  are  apt  to  clog  the  filters, 
which  require  careful  management  and  frequent  renewal  of  the  filtering 
medium. 


WATER  235 

It  has  been  stated  that  water  abounding  in  certain  forms  of  algfe  has 
proved  fatal  to  the  animals  which  drank  of  it. 

It  may  be  useful  to  summarise  what  has  been  stated  as  to  upland  surface 
waters  from  various  geological  formations  and  soils  as  follows  : 

The  Kivers  Pollution  Commissioners,  1868  {op.  ciL),  ascertained  that 
waters  from  the  various  geological  formations  of  the  British  Islands  had  the 
following  composition : — 

1.  Upland  Surface  Waters  from  Igneous  i^oc/bs.— SoUds  1-1  to  8*9  grains 
per  gallon ;  average  3-6  grains.     Hardness  0°-6  to  4°-l  ;  average  l°-5. 

2.  Upland  Surface  Waters  from  Metamorphic,  Cambrian,  Silurian,  and 
Devonian  i?oc/ts.— Solids  1-5  to  8*7  grains  per  gallon;  average  3-6  grains. 
Hardness  0°-3  to  4°-8  ;  average  l°-8. 

3.  Upland  Surface  Waters  from  the  Yoredale  and  Millstone  Grits,  and 
the  Non-Calcareous  portion  of  the  Coal  Meastires. — Solids  3-2  to  10*5  grains 
per  gallon  ;  average  6-1  grains.     Hardness  0°-6  to  6°-3  ;  average  3°-3. 

4.  Upland  Surface  Water  from  Lower  London  Tertiaries  and  Bagshot 
Beds. — Sohds  4-1  to  9-2  grains  per  gallon ;  average  5*9  grains.  Hardness 
l°-8  to  3°-9  ;  average  2°-7. 

5.  Upland  Surface  Water  from  the  Calcareous  portions  of  Silurian  and 
Devonian  Eoc^s.— Solids  8-6  to  10-1  grains  ;  average  9-6  grains.  Hardness 
5°-2  to  6°-7  ;  average  6°. 

6.  Upland  Surface  Water  from  Mountain  Limestotie. — Solids  8*7  to  16*4 
grains  per  gallon  ;  average  11-9  grains.    Hardness  6°-9  to  10°-2  ;  average  8°-9. 

7.  Upland  Surface  Waters  from,  the  Calcareous  portion  of  the  Coal 
Measures. — Solids  7"1  to  54-1  grains  per  gallon ;  average  16  grains.  Hardness 
4°'3  to  17°-5  ;  average  8°-6. 

8.  Upland  Surface  Waters  from  the  Lias,  New  Bed  Sandstone,  Conglo- 
merate Sandstone,  and  Magnesian  Limestone. — Solids  7*8  to  18"4  grains  per 
gallon  ;  average  13-2  grains.     Hardness  4°-2  to  17°'4  ;  average  9°-9. 

9.  Upland  Surface  Waterfront,  Oolites. — Solids  12-2  grains  per  gallon; 
hardness  8°'7 — in  the  one  sample  analysed. 

10.  Surface  Waters  from  Cultivated  Land  in  Non- Calcareous  Districts.^ 
Solids  3'7  to  12-7  grains  per  gallon ;  average  6*7  grains.  Hardness  1°'5  to 
7°-l ;  average  3°-4. 

11.  Surface  Waters  from  Cultivated  Land  in  Calcareous  Districts. — 
Solids  9"3  to  77'3  grains  per  gallon  ;  average  20*7  grains.  The  solids  rarely 
fell  below  14  grains  per  gallon.  Hardness  5°*5  to  47°'l  ;  average  14°"4.  The 
hardness  rarely  fell  below  14°. 

Spring  Watebs 

Springs  yield  water-supplies  of  a  varied  character.  They  may  be  classi- 
fied under  three  heads  :  land  springs,  main  springs,  and  intermittent  springs 
or  bournes. 

Land  springs  are  springs  of  water  formed  by  the  percolation  of  water 
through  superficial  porous  soils,  such  as  sand,  gravel,  or  alluvial  earth,  over- 
lying impervious  strata,  such  as  clay.  Where  the  two  strata  —the  impervious 
and  the  pervious — crop  out  to  the  surface,  or  when  the  line  of  junction  of 
the  two  strata  is  tapped,  aland  spring  appears.  Such  springs  are  frequently 
met  with  in  the  carrying  out  of  drainage  and  sewerage  works,  and  during  the 
sinking  of  wells.  Their  yield  of  water  is  uncertain  and  precarious,  depend- 
ing upon  the  extent  of  available  porous  collecting  area,  which  may  be  small. 
They  are,  however,  frequently  replenished  by  the  percolation  from  heavy 
summer  showers  which  do  not  affect  deeper  springs  and  wells  ;  but  they 


230  HYGIENE 

are  also  affected  by  season,  the  yield  of  water  increasing  durinp:  the  winter 
months,  October  to  March,  and  decreasing  during  the  summer  months, 
April  to  September. 

In  adopting  a  land  spring  as  a  som-ce  of  water-supply  for  a  house,  the 
yield  of  water  at  one  particular  period  of  the  year — especially  the  yield  in 
the  spring — cannot  be  relied  on  as  to  quantity.  The  autumn  yield  is  a 
safer  guide  to  the  abundance  of  the  available  supply.  It  is  always  safest  to 
gauge  the  spring  several  times  during  the  year,  and  more  especially  during 
the  summer  and  autumn  seasons. 

Main  springs  are  those  deep-seated  springs  whose  source  is  the  main 
water  percolating  through  great  thiclmesses  of  porous  rock  overlying  an 
impervious  stratum  ;  and  frequently  the  collecting  area  is  remote  from  the 
spring  itself.  These  springs  are  chiefly  met  with  in  regular  geological 
formations,  such  as  the  chalk  and  green  sand.  When  the  stored-up  water 
is  confined  by  an  overlying  stratum  of  impervious  material,  we  have  the 
conditions  requisite  for  the  formation  of  an  artesian  well.  On  boring 
through  such  an  upper  impervious  stratum  of  rock  till  the  water-bearing 
stratum  is  penetrated,  the  head  or  pressure  of  water  in  the  water-bearing 
layers  of  rock  may  force  the  water  up  the  bore-hole  to  a  considerable  height. 
The  latent  spring  is,  in  fact,  tapped  and  made  available  for  use.  Good  examples 


^^^^^^^  BOURNE 

RIVER 

Pig.  84. 

of  artesian  wells  are  met  with  in  the  Thames  Valley,  and  furnish  excellent 
water-supplies.  On  the  banks  of  the  river  Wandle,  near  Merton  in  Surrey, 
the  water  in  such  wells  riges  to  the  level  of  a  few  feet  above  the  surface  of 
the  soil,  and  by  means  of  inverted  J -shaped  pipes  is  discharged  in  such  a 
manner  as  turn  water-wheels. 

Intermittent  springs,  or  '  bournes,'  as  they  are  technically  termed,  were 
formerly  supposed  to  be  formed  by  natural  syphons,  emptying  from  time  to 
time  underground  reservoirs  of  water ;  but  no  such  syphon  emptying  an 
underground  reservoir  has  ever,  in  fact,  been  discovered ;  and  all  the 
phenomena  connected  with  these  springs  can  be  satisfactorily  accounted  for 
on  simpler  principles.  Such  springs  are  usually  found  irear  the  chalk,  as 
e.q.  near  Croydon,  and  at  Assendon. 

In  fig.  81  the  dotted  line  represents  the  level  of  the  underground  water 
in  the  neighbourhood  of  a  valley  traversed  by  a  river  and  bounded  on  one 
side  by  hills.  This  line  of  level  rises  from  the  river  to  the  hills,  in  which 
the  water  will  stand  at  a  much  higher  level  than  at  the  river ;  this  being 
invariably  the  case  with  underground  water.  In  winter  the  declivity  of  the 
underground  water-level  will  be  much  steeper  than  in  summer.  The 
appearance  and  disappearance  of  the  bourne  will  depend  upon  whether  the 
water-level  at  the  spot  marked  '  Bourne  '  comes  to  the  level  of  the  surface,  or 


WATEB  237 

remains  beneath  the  hnpervious  strata.  Bournes  nearly  invariably  make 
their  appearance  in  winter,  when  the  level  of  the  under j,f round  water  is 
highest,  and  disappear  in  summer,  when  this  is  lowest.  In  1870  there  was, 
however,  a  remarkable  exception  to  this  uniformity,  for  in  that  year  the 
Assenton  Spring  broke  out  in  June.  In  1879  the  spring  rains  were  excessive, 
and  percolation  into  the  deeper  strata  of  rock,  which  in  summer  is  usually 
nil,  took  place  to  large  extent ;  and  thus  the  appearance  of  the  spring  in  the 
unusual  month  of  June  is  readily  explained.  Spring-  and  well-waters  may  bo 
classed  together  ;  and  it  is  among  these  waters  that  the  widest  differences,  as 
to  the  quality  and  quantity  of  their  saline  constituents,  is  encountered. 
Waters  drawn  from  shallow  surface  wells  may  exhibit  all  the  characteristics 
of  surface  waters  from  the  same  locality  ;  or,  more  commonly,  they  are 
charged  with  the  washings  of,  and  percolations  of  surface  water  through,  a 
shallow  soil  loaded  with  animal  and  vegetable  organic  impurities.  Waters 
from  deep  springs  and  wells,  on  the  other  hand,  are  usually  of  practically 
uniform  temperature,  whatever  be  the  variations  in  the  temperature  of  the 
atmosphere,  and  when  from  similar  soils  show  but  little  variation  m  their 
saline  and  other  constituents.  With  respect  to  their  saline  constituents, 
there  is  the  utmost  variation  in  their  composition  ;  and  these  waters  may 
vary  from  a  fairly  soft,  palatable  Avater,  to  that  of  a  saline,  chalybeate, 
arsenical,  or  purgative  fluid.  Their  freedom  from  organic  contamination  is 
usually  almost  complete  ;  and  hence,  if  their  salinity  be  not  too  great,  and  if 
they  are  free  from  more  than  mere  traces  of  potent  medicinal  substances, 
such  waters  are  agreeable  refreshing  beverages,  and  are  well  adapted  for 
drinking  purposes  and  for  town  water-supplies.  Deep  weU-waters,  indeed, 
yield  the  best  water-supplies,  and  those  to  which  the  fewest  exceptions  can 
be  taken,  save  on  the  score  of  hardness  or  the  cost  involved  in  pumping. 
The  water-supply,  on  the  contrary,  from  shalloAv  wells  is,  as  a  rule,  bad, 
and  always  dangerous  if  the  well  be  in  the  proximity  of  dwelling-houses, 
middens,  privies,  ashpits,  stables,  and  the  like  sources  of  contamination  ; 
for  the  purity  of  such  waters  is  at  any  moment  liable  to  be  impaired  by  the 
sudden  irruption  of  organic  filth  and  the  soakage  of  liquids.  The  writer 
has  found  the  shallow  wells  of  London  to  yield  water  containing  as  much 
as  200  and  even  300  grains  per  gallon  of  solids — hard,  abounding  in 
sulphate  of  calcium — and  yet  withal  clear,  sparkling,  and  pleasant  to  the 
taste.  A  memorable  instance  of  an  outbreak  of  Asiatic  cholera  followmg 
the  use  of  such  a  water  is  recorded  in  the  classical  instance  of  the  Golden 
Square  pump,  by  Dr.  Snow.     This  case  will  be  again  adverted  to. 

When  shallow  wells  are  sunk  into  an  alluvial,  gravelly  soil,  in  the 
immediate  proximity  of  a  river,  they  may  become  contaminated  with  filth 
carried  laterally  to  great  distances,  owing  to  the  '  set '  of  the  ground-water 
in  a  particular  direction,  generally  towards  the  bed  of  a  river.  Such  under- 
ground streams  are  by  no  means  uncommon,  and,  when  pure,  form  uniform 
and  excellent  supplies,  such  as  those  which  have  furnished  water  to  Dresden. 

Under  other  conditions,  shallow  wells  should,  if  possible,  be  avoided  as 
sources  of  water-supply.  They  are  very  prone  to  be  contaminated  with 
organic  filth,  derived  from  the  soakage  of  sewage  and  slop-water  into  a  porous 
soil.  It  was  formerly  supposed  that  a  well  drains  an  area  extending  over 
a  distance  in  radius  twice  the  depth  of  the  well.  No  general  rule  can, 
however,  be  laid  down,  and  often  the  distance  is  much  greater  than  this. 
Such  wells  can  never  be  considered  safe,  unless  they  are  sunk  through  an 
impervious  bed  of  soil  into  a  porous  stratum  beneath,  and  are  well  cemented 
down  to  the  clayey  stratum.  Wells  which  do  not  conform  to  this  rule  are 
too  abundant  in  most  rural  districts,  and  are  fertile  sources  of  mischief. 


238  HYGIENE 

Aroimd  a  well,  tlie  surface  of  the  ground- water  in  the  soil  will  be  found  to 
lake  the  form  of  a  hollow  inverted  cone,  with  its  apex  at  the  level  of  the 
■water  in  the  well,  the  base  of  the  cone  merging  imperceptibly  in  the  general 
level  of  the  adjacent  ground-water.  When  the  well  is  pumped,  the  apex  of 
the  cone  will  be  depressed,  and  its  area  will  be  extended — the  cone  becom- 
ing flattened  out.  The  drainage  area  of  the  well  will  thus  be  increased,  and 
if  there  be  any  cesspool,  pervious  sewer,  or  leaky  drain  within  the  area  of  the 
cone,  the  polluting  liquids  will  be  drawn  into  the  well  by  suction.  Hence 
the  great  danger  attendant  on  the  use  of  shallow  wells,  and  all  wells  sunk 
into  pervious  soils  only. 

Some  years  a<,^o  the  town  of  Croydon  in  Surrey  was  visited  by  an' 
epidemic  of  typhoid  fever,  which  was  traced  to  the  water  derived  from  deep 
wells.  Mr.  Baldwin  Latham  made  observations  which  showed  that  when 
the  pumps  were  worked  the  level  of  the  ground-water  was  lowered,  and 
sewage  was  sucked  out  of  the  seAvers,  passing,  as  he  alleged,  into  the  wells 
supplying  Croydon. 

Wells  in  proximity  to  the  sea  generally  afford  a  saline  and  somewhat 
brackish  water,  containing  excess  of  magnesium  and  sodium  salts,  without 
doubt  derived  from  the  presence  of  the  salts  of  sea-water.  Even  when  the 
wells  are  sunk  to  a  considerable  depth  below  the  level  of  the  sea,  it  must  not 
be  supposed  that  there  is  any  appreciable  direct  percolation  of  sea-water  into 
them,  for  it  will  be  found  that  the  '  set '  of  the  underground  water  around  the 
well  is  towards  the  sea.  It  is  more  probable  that  the  advent  of  sea-salts  is  due 
to  liquid  diffusion,  the  salts  diffusing  backwards  into  the  w^ell.  If  it  were 
otherwise,  the  water  in  the  wells  would  be  more  than  brackish,  and  would  be 
salt  water.  That  sea-salts  will  find  their  way  into  wells  situated  at  a  great 
distance  from  the  sea  or  a  tidal  river,  is  shown  by  the  observation  of  the 
late  Dr.  de  Cliaumont,  who  found  in  a  place  near  the  Humble  Eiver  in 
Hampshire,  that  the  tide  affected  the  water  at  a  distance  of  2,240  feet,  or 
nearly  half  a  mile  ;  the  well  itself  being  83  feet  deep,  and  140  feet  above 
mean  water-level.     ('  Lect.  on  State  Med.  1875,'  p.  91.) 

Driven  Wells  or  Tube  Wells. — These  are  also  termed  Abyssinian  wells, 
in  consequence  of  their  having  been  used  during  the  Abyssinian  war  to 
supply  water  to  the  British  troops.  They  are  very  serviceable  in  country 
districts  where  the  shallow  surface  wells  afford  polluted  supplies,  and  where 
a  better  and  purer  water  can  be  obtained  by  penetrating  through  an  imper- 
vious clay  into  the  more  porous  water-bearing  strata  beneath.  Their  con- 
struction is  very  simple.  An  iron  pipe,  1^  to  2  inches  in  diameter,  is  furnished 
at  its  lower  end  with  a  hard  steel  point,  above  which  the  pipe  is  pierced  with 
holes  to  admit  of  the  inflow  of  water.  The  pipe  is  driven  perpendicularly 
into  the  soil  by  means  of  a  mallet  or  falling  weight ;  a  second  length  is 
attached  by  means  of  a  joint  or  coupling,  and  the  lengthened  pipe  is  again 
driven  into  the  ground.  The  addition  of  successive  lengths  of  pipe  is  con- 
tinued until  water  is  reached.  Finally  a  small  pump  is  attached  to  the 
uppermost  length  of  pipe,  and  the  well  is  complete. 

Leakage  of  sewage  into  tube-wells  is  much  less  likely  to  occur  than 
into  ordinary  shallow  wells.  Nevertheless,  when  the  pump  is  vigorously 
worked,  sewage  may  be  drawn  into  the  tube  from  a  considerable  distance. 
Of  course,  tube-wells  are  not  adopted  for  any  but  limited  supplies  of  water. 

Besides  imderground  springs  on  the  continent  of  Europe,  and  also  in 
America,  it  is  not  uncommon  to  obtain  supplies  of  drinking  water  from 
underground  tanks,  tunnels,  and  galleries  sunk  parallel  to  the  bed  of  a 
river,  and  in  the  proximity  of  this.  The  theory  of  these  constructions 
was   that  water  would  percolate  or  filter  from  the  bed  of  the  river  into 


WATER  239 

the  reservoir  constructed  for  its  reception.  This  supposed  percolation  can, 
however,  occur  but  rarely ;  and  nearly  invariably  it  is  the  underground 
water,  intercepted  in  its  passage  to  the  river,  that  furnishes  the  water  for 
use.  Should  the  underground  water  be  not  intercepted  it  gradually  finds  its 
way  to  the  river,  into  and  not  out  of  which  percolation  almost  invariably 
takes  place.  It  is  well  known,  for  instance,  that  the  river  Thames  is  in 
this  way  largely  fed  by  springs  of  such  ground-water  at  various  points  in 
its  course. 

That  the  above  is  the  true  explanation  of  the  source  of  water-supply  where 
such  underground  tanks  are  constructed  is  proved  by  the  experience  of  Toulouse, 
where  the  supply  of  water  was  largely  increased  by  removing  such  a  tank  to 
a  greater  distance  from  the  river  Garonne,  and  intercepting  the  ground- 
water at  a  higher  level ;  for,  as  is  elsewhere  stated,  the  level  of  the  ground- 
water invariably  rises  as  we  recede  from  a  river.  The  experience  of  Dresden 
is  also  significant,  and  to  the  same  effect.  The  relative  temperatures  of  the 
river,  the  ground- water  generally,  and  the  water  in  the  tanks  in  summer — 
and,  further,  the  hardness  of  the  water  in  wells  near  the  river^ — all  support  the 
same  view  as  to  origin.  Lastly,  it  is  known  that  by  pumping  from  a  well 
near  the  banks  of  a  river,  as  e.g.  the  Elbe,  the  level  of  the  ground-water 
is  depressed  over  a  wide  area.  It  is  manifest,  too,  that  were  the  water  of 
a  river  to  percolate  outwards  through  its  bed,  this  would  soon  be  so  silted 
up  by  the  finely  divided  suspended  particles  in  the  water  as  to  put  a  speedy 
stop  to  the  percolation.  On  the  other  hand,  the  groimd- water  having  no  such 
suspended  particles,  when  filtering  from  a  coarser  into  a  more  finely  divided 
stratum,  will  not  clog  the  pores  of  the  river  bed,  but  rather  will  tend  to  keep 
these  open.  It  is  remarkable  that  the  underground  tanks  and  galleries 
referred  to,  though  constructed  on  a  false  theory,  have  been  so  successful  as 
they  have  generally  proved  to  be. 

Occasionally  the  flow  of  underground  water  through  fissures  in  the  chalk 
is  utilised,  and  made  to  furnish  an  abundant  water-supply,  which  may  be  of 
considerable  organic  purity,  as,  for  example,  at  Brighton,  where  the  necessary 
works  were  devised  by  Mr.  Easton.  This  is  done  in  the  following  manner. 
At  Brighton,  and  other  places  on  the  sea-coast,  little  streams  of  water  may 
be  seen  flowing  seawards  from  the  higher  part  of  the  foreshore.  These  are 
commonly  but  erroneously  supposed  to  be  formed  by  sea- water  which  has 
been  dammed  back  into  the  porous  strata  at  high-water.  But  when  tested 
these  streamlets  are  found  to  be  composed  of  fresh  water.  Further  exami- 
nation shows  that  where  the  coast  is  formed  of  pervious  strata,  as,  for 
example,  cbalk,  the  level  of  the  underground  water  forms  a  curve,  beginning 
at  a  point  between  high  and  low-water  level,  and  rising  as  the  sea  is  receded 
from.  The  head  or  pressure  of  the  underground  water  is  always  forcing,  or 
tending  to  force,  the  underground  water  out  of  the  rock  at  the  point  where 
the  level  of  this  comes  out  on  the  foreshore,  whence  at  low  water  the  issuing 
water  becomes  visible.  In  winter  the  water-level  in  the  soil  forms  a  steeper 
declivity  than  in  summer,  when  the  underground  water  stands  at  a  lower 
level  in  the  subsoil.  By  sinking  galleries  into  the  chalk  behind  Brighton, 
and  parallel  with  the  line  of  sea-coast,  down  to  a  level  with  the  low  or  summer 
level  of  the  underground  water,  the  riUs  of  this  constantly  passuig  seawards 
through  the  fissures  in  the  chalk  rock  are  tapped,  and  utilised  for  water-supply. 

In  adopting  such  a  source  of  water  as  has  been  described,  great  care  is 
previously  necessary  to  ascertain  that  the  water  is  uncontaminated,  since 
fissures  in  the  chalk  are  liable  to  serve  as  conduits  for  sewage  from  great 
distances  ;  and  it  is  these  chalk  fissures  which  often  render  a  water-supply 
drawn  direct  from  the  chalk  a  polluted  or  suspicious  one. 


240  HYGIENE 

The  water  derived  from  deep  artesian  wells  in  the  British  Isles  is  usually 
of  excellent  quality,  and  remarkably  free  from  oi'ganic  matter.  Exceptionally 
such  wells  yield  a  brackish  water.  In  England,  artesian  wells  are  often  of 
great  depth,  being  sunk  through  the  chalk  and  into  the  lower  greensand 
formation  where  this  is  covered  by  the  gault.  But  artesian  wells  are  not 
always  or  necessarily  sunk  in  the  above-named  geological  strata.  What  is 
required  for  their  formation  is  that  a  well  be  sunk  through  an  upper  imper- 
vious stratum  into  a  subjacent  pervious  and  water-bearing  stratum,  in  which 
the  water  is  confined  under  such  ahead  or  pressure  that  when  tapped  it  rises 
in  the  well-tube  or  bore-hole  to  a  considerable  height,  or  even  to  the  surface. 
Unfortunately  the  water  from  artesian  wells  is  often  saline,  and  is  the  water 
holding  in  solution  the  salts  of  saline  beds  of  remote  geological  formation, 
probably  from  lakes  and  inland  seas.  But  when  not  unduly  saline,  these 
waters  are  of  excellent  quality,  clear,  colourless,  of  uniform  temperature 
throughout  the  year,  and  pleasant  to  the  taste.  These  are,  however,  some- 
times rather  hard ;  but  those  in  and  about  London  are  decidedly  alkaline 
from  the  presence  of  several  grains  of  bicarbonate  of  sodium  in  each  gallon 
of  water,  and  are  hence  somewhat  soft.  Some  deep  weU-waters  are  warm, 
as,  e.g.  those  of  Bath  ;  and  then  are  unfitted  for  ordinary  drinking  purposes. 
Others,  again,  have  a  slight  odour  of  sulphuretted  hydrogen,  speedily  lost  on 
free  exposure  to  the  air.  These  feebly  sulphuretted  waters  may  be  trouble- 
some when  stored  in  cisterns,  in  consequence  of  the  readiness  with  which 
they  become  filled  with  filamentous  vegetable  growths. 

Sometimes  water  is  obtained  from  wells  and  borings  made  direct  into  the 
solid  chalk,  which  is  not  usually  a  water-bearing  rock.  In  such  cases  a  bore- 
hole is  driven  into  a  fissure  or  fault  in  the  rock,  such  fissures  being  common 
in  the  chalk,  and  acting  when  filled  with  water  as  underground  streams. 
"Where  the  fissures  have  one  general  direction,  an  adit  or  channel  may  be 
made  at  right  angles  to  their  course — as  at  Brighton,  where,  as  has  been  already 
stated,  the  water  is  systematically  abstracted  to  form  the  town  water-supply. 

The  proposals  that  have  been  made  in  the  instances  of  London  and  other 
large  cities  to  substitute  a  supply  from  deep  wells  for  a  river-supply  have 
generally  been  viewed  with  doubt  by  the  majority  of  engineering  authorities. 
Deep  wells  may  yield  a  tolerably  constant  and  copious  supply  of  water,  if  not 
unduly  taxed  ;  but  it  by  no  means  follows  that  were  a  much  larger  supply 
attempted  to  be  obtained  from  these  strata,  which  yield  a  moderate  supply,  the 
yield  would  be  commensurate  with  anticipations.  The  quantity  of  water 
present  in  strata  at  any  one  time  is  limited  ;  and  the  experience  derived  from 
the  artesian  wells  in  a  London  district  is  that  the  level  of  the  deep  water,  and 
hence  its  head  or  pressure,  is  steadily  falling  year  by  year,  and  that  the 
underground  supply  from  such  wells  is  by  no  means  an  unlimited  one.  At 
Guy's  Hospital,  the  artesian  well  formerly  yielded  a  supply  adequate  to  the 
needs  of  the  institution  ;  whereas  now  it  affords  only  one  half  of  the  requisite 
quantity,  and  the  well  is  pumped  on  alternate  days,  and  not  every  day  as 
formerly. 

Exceptionally,  an  artesian  well  may  furnish  a  polluted  water-supply : 
and  some  have  furnished  mimistakable  evidence  of  the  sources  of  their 
impurities  in  the  shape  of  dead  fish,  marsh  plants,  roots,  seeds,  &c.  It  is 
supposed  that  in  some  of  these  cases  these  materials  have  been  conveyed 
in  subterranean  conduits  from  great  distances. 

Generally,  it  may  be  said  that  spring  waters,  if  not  of  a  thermal,  medicinal, 
.aperient,  or  chalybeate  character  from  the  too  great  or  unusual  nature  of  their 
constituents,  furnish  pure  and  excellent  supplies  of  water.  Indeed,  the 
German  Public  Health  Association  some  years  ago  arrived  at  the  conclusion 


WATER  241 

that  spring  waters  alone — either  those  coming  naturally  to  the  surface,  or  ob- 
tained from  wells— are  the  only  admissible  sources  of  water-supply.  This 
too  sweeping  resolution  was,  however,  subsequently  rescinded.  Nevertheless, 
it  shows  what  a  high  value  German  hygienists  very  properly  attach  to  springs 
as  sources  of  the  very  best  water-supply. 

The  advantages  of  spring  waters  have  been  thus  summarised  by  the 
Rivers  Pollution  Commissioners  :— 'That  preference  should  always  be  given 
to  spring  and  deep-well  water  for  purely  domestic  purposes,  over  even  upland 
surface  water,  not  only  on  account  of  the  much  greater  intrinsic  chemical 
purity  and  palatability  of  these  waters,  but  also  because  their  physical  pro- 
perties render  them  peculiarly  valuable  for  domestic  supply.  They  are 
almost  invariably  clear,  colourless,  transparent,  and  brilliant,  qualities  which 
add  greatly  to  their  acceptability  as  beverages  :  whilst  their  uniformity  of 
temperature  throughout  the  year  renders  them  cool  and  refreshing  in  summer, 
and  prevents  them  from  freezing  readily  in  winter.  Such  waters  are  of 
inestimable  value  to  communities,  and  their  conservation  and  utilisation  are 
worthy  of  the  greatest  efforts  of  those  who  have  the  pubhc  health  under 
their  charge.' 

The  Eivers  Pollution  Commissioners,  1868,  analysed  a  large  number  of 
well  waters  from  shallow  wells  with  the  following  results  : — 

1.  Waters  from  shallow  wells  in  or  tcpon  Silurian  Bocks  and  Gneiss. — 
Solids  2-4  to  70-1  grains  per  gallon  ;  average  16-7  grains.  Hardness  2°-4  to 
29°'l ;  average  7°-6. 

2.  Waters  from  shallow  wells  on  Devojiian  Bocks. — Solids  8"5  to  73'6 
grains  ;  average  27*5  grains.     Hardness  3°*5  to  39°  ;  average  14°-6. 

3.  Waters  frofii  shalloio  ivells  on  the  Yoredale  and  Millstone  Grits. — 
Solids  4*1  to  93-5  grains  per  gallon  ;  average  35-1  grains.  Hardness  2°  to 
63° ;  average  22°'l. 

4.  Waters  from  shalloio  tvells  on  the  Goal  Measiires. — Solids  6*6  to  154*6 
grains  per  gallon  ;  average  48  grains.    Hardness  2°-4  to  98°-6  ;  average  24°-4. 

5.  Waters  from  shalloiv  tvells  in  or  on  Mountain  Limestone  and  Mag- 
nesian  Limestone. — Solids  32*1  to  76*2  grains  per  gallon  ;  average  50*4 
grains.     Hardness  28°-5  to  62°  ;  average  40°*9. 

6.  Water  from  shallow  wells  in  or  on  Neiv  Bed  Sandstone. — Sohds  14-4 
to  168*1  grains  per  gallon  ;  average  71*1  grains.  Hardness  12°  to  89° ; 
average  34°*5. 

7.  Water  from  shalloiv  wells  in  or  upon  the  Lias. — Solids  26  to  214*8' 
grains  per  gallon  ;  average  77*8  grains.  Hardness  1°*9  to  81°*8  ;  average 
35°*8. 

8.  Waters  from  shallow  wells  in  or  on  the  Oolite. — Solids  21*7  to  188*7 
grains  per  gallon;  average  64  grains.  Hardness  16° *1  to  55°*2  ;  average 
82°-4. 

9.  Waters  from  shallow  wells  in  or  on  the  Upper  and  Lower  Greensand 
and  Wealden  Beds. — Solids  7*4  to  266*8  grains ;  average  50  grains. 
Hardness  2°*7  to  56°*4  ;  average  19°*7. 

10.  Waters  from  shallow  wells  in  or  on  the  Chalk. — Solids  22*7  to  111*4 
grains  per  gallon  ;  average  55*6  grains.   Hardness  16°*7  to  50°  ;  average  30°*5. 

11.  Waters  from  shallow  wells  in  Gravel  on  the  London  C/a?/.— Sohds 
22*3  to  277*5  grains  per  gallon ;  average  71*2  grains.  Hardness  10°  to 
133°*7 ;  average  35°*6. 

12.  Waters  from  shallow  wells  in  Bagshot  Beds. — Solids  16*2  to  200*8 
grains  per  gallon  ;  average  82*2  grains.  Hardness  9°*2  to  92°*2  ;  average 
38°*5. 

13.  Water  from  shallow  ivells  in  Fluvio-Marine  Series. — Sohds  5*7  to 

VOL.    I.  K 


242  HYGIENE 

■JtG-3  grains   per  gallon  ;    average  19-1    grains.      Hardness  3°-2   to  25°-5 ; 
average  10°'8. 

14.  Waters  from  shallow  wells  in  AlUivium  and  Gravel. —  Solids  20 
to  224-5  grains  per  gallon ;  average  69-6  grains.  Hardness  o°'2  to  10G°-7  ; 
average  83°*3. 

ElVER-WATER 

Eiver-water  varies  greatly  in  quality,  and  also  as  to  its  organic  purity. 
Some  rivers  yield  water  of  unimpeachable  quality  :  whilst  others,  as  e.g.  the 
Irwell  at  Manchester,  afford  only  a  filthy,  disgusting  liquid.  The  saline 
constituents  of  river- water  vary  according  to  the  kinds  of  soil  through  which 
the  tributary  streams  flow,  the  springs  or  ground-water  which  find  then- 
outlet  in  the  bed  of  the  river,  and  the  nature  of  the  soil  through  which  the 
river  itself  flows.  Generally,  it  may  be  stated  that  a  river- water  is  less  hard 
and  saline  than  the  water  of  its  tributary  streams  in  the  lower  part  of  its 
■course  ;  but  it  may  be  much  harder  and  more  saline  than  the  waters  of  the 
upper  tributaries,  if  these  flow  from  a  country  abounding  in  igneous  rocks. 
The  chalk  held  in  solution  by  carbonic  acid  in  the  contributory  springs 
becomes  in  part  thrown  out  of  solution  by  the  escape  of  carbonic  acid  on 
exposure  to  the  atmosphere  during  flow  in  the  river,  and  this  tends  to 
diminish  the  hardness  of  the  water. 

The  liability  to  contamination  of  the  water  of  rivers  in  agricultural,  and 
still  more  in  manufactuiiug  districts,  is  a  great  drawback  to  the  use  of  such 
waters  as  sources  of  domestic  supply.  Fortunately,  the  self-purifying  action 
going  on  in  rivers  is  very  great,  and  there  is  the  compensating  advantage 
that  in  large  rivers  of  considerable  length  the  supply,  as  in  the  case  of  the 
Thames,  is  fairly  constant  and  abundant ;  and  it  must  be  admitted  that 
river- waters,  even  after  a  few  miles'  flow  and  efficient  filtration,  so  as  to 
remove  all  suspended  matters,  sometimes  form  a  fairly  safe  source  of  supply ; 
and  in  proof  of  this  the  supply  of  London  with  drinking  water  taken  from  the 
Thames  above  the  tidal  lock  at  Teddington  may  be  adduced  as  a  signal 
instance.  Before  the  chief  water-supply  of  the  metropolis  was  by  statute 
compelled  to  be  taken  exclusively  from  the  river  above  the  unpolluted 
reaches,  cholera  and  perhaps  other  diseases  were  produced  among  the 
inhabitants  of  London  by  the  drinking  of  polluted  river- water ;  but  since 
about  18G6,  when  the  change  was  effected,  no  appreciable  amount  of  disease 
has  ever  been  proved  to  have  been  caused  in  the  metropolis  of  England  by 
means  of  the  filtered  water  as  delivered  to  the  consumers.  This,  coupled 
with  the  fact  that  no  source  of  supply  so  abundant,  sure,  and  uniform  exists 
Avithin  a  reasonable  distance  of  the  metropolis,  has  hitherto  effectually  stood 
in  the  way  of  the  adoption  of  any  other  water-supply  for  London. 

What  has  just  been  said  must  not  be  taken  to  indicate  that  the  pollution 
■of  a  river-water  by  filth  is  of  no  consequence,  provided  there  be  a  good  flow 
of  a  few  miles  before  the  intake  of  a  drinking  water-supply  is  reached.  The 
writer  merely  wishes  to  indicate  that  the  danger  attending  the  use  of  river- 
water  which  has  been  antecedently  polluted  has  been  exaggerated.  The 
late  Professor  Rolleston  expressed  an  opinion  that  the  introduction  of 
-cholera  germs  into  the  Thames  at  Oxford  might  result  in  an  outbreak  of 
that  disease  in  London,  but  these  anticipations  have  not  been  reahsed.  Dr. 
Frankland  has  also  stated  that  '  there  is  no  river  in  the  United  Kingdom 
long  enough  to  purify  its  waters  spontaneously  if  they  have  once  become 
contaminated  with  sewage  ('  Applied  Chemistry,'  p.  552),  a  statement  to 
which  few  would  venture  to  subscribe  in  the  present  day.  The  truth 
appears   to   be  that   rivers   are  able  to   get   rid  of  their  sewage  pollution 


WATEB  243 

hy  the  combined  agencies  of  oxidation,  growth  of  vegetation,  and  the 
activities  of  organisms  such  as  bacteria  and  the  lower  forms  of  vegetable 
growth  ;  and  there  is  practical  but  not  absolute  safety  if  the  polluting 
material  be  not  introduced  in  excessive  proportion,  and  the  river  have  a  free 
flow  of  several  miles,  especially  over  a  rocky  bed  and  weirs,  so  as  to  subject 
the  water  to  agitation  and  consequent  abundant  aeration.  The  late  Dr. 
Letheby  and  Dr.  Tidy  have  been  the  strongest  supporters  of  this  hypothesis, 
which  has  also  received  the  support  of  Dr.  Odling.  Nevertheless,  it  must  be 
admitted  that  the  experience  of  1806  with  respect  to  cholera — the  last 
visitation  of  that  disease — is  insufficient  to  enable  a  satisfactory  conclusion 
to  be  drawn,  affirmatively  or  negatively  ;  and  more  recent  experience  appears 
to  show  that  a  flow  of  several  miles  in  a  river  is  insufficient  to  destroy  the 
activity  of  the  poison  of  typhoid  fever. 

Some  rivers  afford  a  highly  polluted  and  dangerous  water,  though 
directly  they  may  receive  no  great  quantity  of  sewage,  or  even  none  what- 
ever. These  rivers  are  derived  from  a  peaty  soil,  or  from  ground-water  and 
springs  in  a  highly  porous  polluted  soil.  A  signal  example  is  the  river 
Blackwater  in  Surrey,  which  comes  from  the  Bagshot  Sands,  a  sandy  porous 
soil,  the  springs  in  which  are  highly  impure.  It  is  stated  that  the  Upper 
Bagshot  Sand  yields  a  pure  water,  whilst  the  Middle  Bagshot  Sand  yields  a 
highly  polluted  water-supply. 

Eiver-waters  in  mining  and  manufacturing  districts  may  become  specifi- 
cally polluted,  so  as  to  render  them  entirely  unfit  to  serve  as  sources  of 
water-supply.  The  Fifth  Eeport  of  the  Elvers  Pollution  Commissioners  deals 
fully  with  these  sources  of  pollution,  in  mining  districts  arising  from 
collieries  and  coal-washing — iron,  copper,  lead,  tin,  arsenic,  manganese,  and 
baryta  mines  ;  from  china-clay  works,  and  from  metal  manufactures.  Their 
First  and  Third  Eeports  treat  of  pollution  by  manufacturing  refuse.  The 
Commissioners  (Sixth  Eeport,  p.  418),  while  admitting  that  the  drainage- 
water  from  arable  lands  is  preferable  to  that  from  polluted  shallow  wells, 
apparently  were  of  opinion  that  river-water  is  inadmissible  as  a  somxe  of 
town  supplies,  a  conclusion  which  the  writer  considers  far  too  sweeping. 


QUANTITY   OF  WATEE  FOE  DOMESTIC   AND   OTHER   SUPPLIES 

The  amount  of  water  needed  for  domestic  and  other  uses  is  a  matter  of 
important  consideration  to  Medical  Officers  of  Health.  In  making  ar- 
rangements for  a  town  supply,  he  will  of  course  have  the  aid  of  the  engi- 
neer to  guide  him  as  to  the  quantity  of  water  available  from  a  given  source  ; 
but  in  rural  districts  he  may  have  no  such  assistance.  In  all  cases  his 
advice  will  be  sought  as  to  the  requirements  for  domestic  use,  both  as  regards 
quality  and  quantity.  The  adequacy  of  storage  reservoirs  is  also  a  matter 
to  which  he  cannot  be  indifferent,  though  advice  as  to  the  sufficiency  of  these 
to  supply  the  needs  of  a  community  during  long  periods  of  drought  should 
be  obtained  from  the  meteorologist  and  engineer. 

Different  estimates  have  been  put  forth  as  to  the  minimum  quantity  of 
water  required  for  domestic  purposes,  and  these  vary  greatly,  and  must 
necessarily  vary  according  to  the  habits  of  the  community  to  be  dealt  with  ; 
the  social  class  to  which  the  majority  of  them  belong  ;  the  general  or  partial 
use  of  water-closets  ;  and  the  proportion  of  the  population  using  household 
baths.  A  water-supply  that  would  be  ample  for  a  population  mostly  com- 
posed of  agricultural  labourers  would  be  quite  inadequate  for  the  ordinary 


244  HYGIENE 

needs  of  a  wealtljy  or  even  a  middle-class  town  community.  Happily,  sani- 
tary authorities  are  becoming  alive  to  the  necessity  of  increasing  their  water- 
supplies,  and  such  supplies  as  would  a  few  years  ago  have  been  deemed 
ample,  are  now  admitted  to  be  insuilicient  for  the  maintenance  of  health  and 
comfort.  Yet  it  must  be  admitted  that  greater  economy  in  the  use  of  water 
is  frequently  called  for,  and  that  enormous  quantities  of  water  under  our 
present  systems  of  distribution  in  towns  are  simply  wasted.  The  supply 
should,  nevertheless,  be  liberal,  and  not  niggardly,  lest  health  be  imperilled  ; 
and  it  is  better  to  err  on  the  side  of  excess  than  to  run  the  risk  of  want  of 
water  and  its  consequences — impaired  health,  and  disease.  On  the  average 
of  a  community,  about  one-fourth  of  a  gallon  per  head  per  day  is  the  quantity 
of  water  necessary  for  drinking  purposes.  But  this  is  only  a  small  fraction 
of  that  required  for  domestic  use.  Dr.  Parkes  measured  the  water  actually 
used  in  several  houses,  and  gave  the  following  as  the  amount  used  by  a  man 
of  the  middle  class,  who,  he,  says,  might  be  taken  as  a  fair  type  of  a  cleanly 
man  belonging  to  a  fairly  clean  household : 

Gallons  daily 
per  one  person 

Cooking 0-75 

Fluids  as  drink  (water,  tea,  coffee) 0*33 

Ablution,  including  a  daily  sponge  bath,  which  took  2\  to  3  gallons  .         .  5"0 

Share  of  utensil  and  house  washing     ........  3'0 

Share  of  clothes  (laundry)  washing,  estimated     ......  3"0 

Total 12-08 

This  quantity  is,  perhaps,  not  quite  adequate  for  the  needs  of  the 
average  person  in  most  towns  or  villages,  and  it  is  generally  thought  that  a 
minimum  supply  of  12  gallons  per  head  per  day  is  not  excessive  where  no 
baths  are  used.  A  good  bath  requires  50  gallons  of  water  ;  and  if  general 
baths  are  used  once  a  week,  5  or  6  gallons  per  head  should  be  added  to  the 
daily  consumption  (Parkes).  Where  water-closets  are  used,  an  additional 
allowance  of  6  gallons  per  head  per  day  should  be  further  added  ;  and  2  or 
3  gallons  should  be  allowed  for  waste.  Thus  we  arrive  at  the  following 
figures,  stating  the  quantity  of  water  required  per  head  per  day  for  purely 
domestic  purposes : 

Gallons 

Drinking  and  cooking 1 

Ablutions  and  general  weekly  baths 7 

Washing  and  laundry 6 

Water-closets       .........     6 

Flushing  and  waste 5 

Total 25 

A  further  quantity  must  be  allowed  for  manufacturing  towns  and  for  trade 
purposes,  flusliing  of  sewers,  street  watering,  and  the  washing  of  horses  and 
other  domestic  animals.  An  allowance  of  35  gallons  is  not  too  much  for 
a  town  supply.  London  has  a  supply  of  about  40  gallons,  and  Glasgow  of 
50  gallons  per  head  per  diem,  and  these  are  thought  by  many  sanitarians  to 
be  too  little. 

Dr.  Pole,  a  high  autliority  on  all  matters  relating  to  water-supply, 
states,  nevertheless  ('  On  Water-Supply,'  pp.  13, 14),  that  the  quantity  actually 
required  for  domestic  consumption,  including  a  fair  allowance  for  household 
purposes,  for  water-closets,  and  for  ordinary  ablutions,  is  probably  not  more 
than  about  10  gallons  per  head  per  day.  But,  in  addition  to  domestic  con- 
sumption, supplies  have  to  be  provided  for  gardens  and  stables,  manufactur- 
ing and  trade  purposes  of  many  kinds,  baths  and  wash-houses,  public  fountains, 


WATER  245 

■watering  streets,  flushing  sewers,  and  extinguisliing  fires  ;  and  he  says  that 
the  quantity  for  these  purposes  will  vary  from  5  to  10  or  more  gallons  per 
head  per  day.  It  is  usual,  he  states,  to  estimate  the  normal  consumption  of 
a  town  at  25  gallons  per  head  per  day,  and  he  thinks  that  this  quantity  will 
be,  or,  at  all  events,  ought  to  be,  a  sufficient  supply  for  all  purposes.  Sani- 
tarians will,  perhaps,  not  be  inclined  to  agree  with  him,  and  may  consider 
25  gallons  per  head  per  day  a  sparse  supply.  With  little  waste  there  is  no 
doubt  that  25  gallons  is  a  better  supply  than  .85  gallons  with  no  adequate 
care  to  prevent  avoidable  waste.  Further,  as  the  above  eminent  engineering 
authority  insists,  water  is  not  only  a  very  expensive  thing  to  provide,  and  its 
excessive  use  not  only  wastes  money,  but  does  positive  mischief  by  increasing 
the  difficulty  of  carrying  it  away.  There  is  certainly  balance  to  be  struck 
between  the  evils  of  a  too  abundant,  i.e.  wasteful,  and  a  too  sparing  supply 
of  water ;  but  of  the  two  evils  the  sanitarian  will  undoubtedly  consider  the 
too  abundant  supply  the  least.  The  advantages  to  a  community  of  an  at  all 
times  ample  supply  of  water  are  incalculable  ;  whilst  the  inconveniences  of 
Sb  too  abundant  supply — if  such  be  possible — are  remediable,  and  by  com- 
parison small. 

In  hospitals  and  infirmaries  an  abundant  supply  of  water  is  a  prime 
necessity,  and  a  copious  extra  supply  should  be  stored  in  tanks  in  case  of 
fire.  In  a  large  London  hospital  (Guy's),  the  daily  quantity  used  is  45 
gallons  per  patient,  or  35  gallons  per  head,  including  resident  staff.  This 
includes  laundry  water,  and  that  used  in  the  Medical  School  and  Laboratories. 
But  provision  should  be  made  for  a  larger  supply  than  this  in  case  of  need. 
In  towns,  where  possible,  the  supply  for  large  establishments  is  economised 
when  supplied  by  meter.  It  is  a  regrettable  fact  that  no  efficient  water-meter 
has  as  yet  been  generally  introduced  for  the  registration  of  small  supplies ;  if 
it  were  otherwise,  there  is  little  doubt  that  great  waste  of  water  would  be 
avoided,  and  that  smaller  supplies  would  suffice,  if  every  householder  had 
his  water  supplied  by  meter. 

The  following  miscellaneous  data  relative  to  the  quantity  of  water 
xequisite  for  water-supplies  are  useful : 

Waste-preventers  of  w.c.'s  require  f  to  2  gallons  for  each  flush  of  the 
•closet ;  even  one  flush  of  2  gallons  is  usually  insufficient  to  keep  the  pan 
clean. 

A  horse  drinks  6  to  10  gallons,  a  cow  6  to  8  gallons,  a  sheep  or  pig  ^  to 
1  gallon  daily  (Parkes).  Where  horses  and  carriages  are  kept,  at  least  16 
gallons  per  horse  per  day  should  be  allowed  for  all  purposes. 

In  non-manufacturing  towns  5  gallons  per  head  per  day  should  be  allowed 
for  trade  purposes  ;  and  in  manufacturing  towns  double  that  amount,  viz. 
10  gallons. 

On  the  strictly  constant  system  of  supply,  with  due  supervision  so  as  to 
prevent  waste,  15  gallons  per  head  per  day  may  suffice  for  a  non-manufactur- 
ing town,  or  not  much  more  than  half  that  required  under  the  wasteful 
intermittent  system. 


INSUFFICIENT   WATEE-SUPPLY 

The  immediate  effect  on  the  human  body  of  an  insufficiency  of  drinking 
-water  is  very  manifest  in  the  form  of  excessive  thirst,  and  an  irresistible 
craving  for  fluids  ;  and  if  no  other  means  of  gratifying  this  craving  is  at  hand, 
the  most  filthy  and  disgusting  liquids  will  be  eagerly  drunk.    There  is,  indeed, 


24G  HYGIENE 

no  need  of  the  body  so  imperative  as  that  for  drink.  But  tLis  condition  is 
not  one  that  often  comes  under  the  notice  of  the  sanitarian  :  rather  it  is  the 
less  immediate  results  of  an  insufficient  water-supply  that  he  has  to  deal  with 
and  combat,  such  as  want  of  personal  cleanliness,  dirty  clothing,  defective 
cooking,  filthy  habitations,  accumulations  of  excreta,  iincleansed  streets, 
courts,  and  alleys,  choked  drains,  and  unflushed  sewers.  The  result  of 
these  defects  is  well  recognised  in  the  general  lowering  of  the  health  of  the 
community,  the  prevalence  of  typhus  and  occasionally  of  typhoid  fevers,  skin 
diseases,  ophthalmia,  and  pcn'liaps  many  other  diseases.  Other,  and  generally 
alcoholic,  fluids  will  be  drunk,  and  thus  the  degradation  of  a  people  having  a 
deficient  water-supply  ^N-ill  be  aggravated.  The  results  are  far-reaching. 
Some  half-century  ago  deficient  water-supplies  were  more  common  than  in 
the  present  day,  and  the  First  and  Second  Reports  of  the  Health  of  Towns 
Commission  for  1844-5  contain  abundant  evidence  of  this. 

It  is  difficult  to  ascertain  how  far  the  health  of  a  town  suffers  from  a 
temporary  scarcity  of  water  during  a  water-famine ;  but  inferentially  we 
should  expect  the  efiects  to  be  considerable.  Generally,  however,  in  the 
'  water-famines '  of  our  British  towns,  the  term  water-famine  is  a  very  relative 
one  ;  and  the  supply  of  water  in  such  times  of  scarcity  of  the  fluid  would  not 
very  many  years  ago  have  been  considered  sufficient  for  domestic  use. 


STOEAGE 

The  storage  of  water  may  be  considered  under  two  heads — 

A.  Storage  of  public  water-supplies. 

B.  Storage  in  and  about  dwelling-houses,  &c. 

A.  Storage  of  Public  Water-Supplies 

The  amount  of  storage  required  for  the  water-supply  of  a  town  necessarily 
varies,  not  only  with  the  numbers  of  the  community  to  be  supplied,  but  also 
according  to  their  habits,  and  the  industrial  occupations  carried  on  ;  and  in 
manufacturing  towns  the  amount  of  water  required  for  industrial  purposes 
may  exceed  that  required  for  domestic  use.  Whatever  be  the  required  daily 
supply,  the  storage  capacity  of  the  reservoirs  in  rainy  districts  should  equal 
150  days'  dry  weather  supply  (Pole) ;  and  in  dry  districts  200  days'  supply. 
These  estimates  apply  to  the  British  Isles  only  ;  and  in  drier  countries  a  much 
larger  storage  must  be  provided.  Dr.  Pole  ('  Water  Supply,'  p.  21)  has 
given  some  simple  and  useful  formulae  for  calculating  the  collecting  area 
requisite,  where  the  rainfall  is  known,  and  the  loss  from  evaporation  fairly 
established. 

If  R  =  the  mean  rainfall  in  a  given  year,  in  inches, 
E  =  the  estimated  loss  by  evaporation,  &c.,  in  inches, 
A  =  the  area  of  gathering  ground  in  acres, 


then 
and 


Gallons  of  water  per  day  =  62  A  (R — E)  ' 

Cubic  feet  of  water  per  year  =  3630  A  (R — Ej 

Mr.  Hawksley's  formula   for  calculating  the  number  of   days'    storage 
requisite  is  to  divide  1000  by  the  square  root  of  the  annual  rainfall  in  inches.. 

'  See  note,  p.  233. 


WATER  247 

1000     1000 


Thus,  with  a  rainfall  of  36  inches,  the  clay's  storage  required  is 


n/3G       6 


=  167  days  ;  and  with  a  rainfall  of  64  inches  is  _--=—-— =  125  days. 

V  64        8 

In  rural  districts,  where  the  wells  supply  a  too  scanty  or  a  polluted  water, 
it  is  often  advantageous  to  combine  a  group  of  villages,  introduce  water  from 
one  source,  and  thus  economise  cost.  It  is  a  misfortune  that  in  England 
there  is  no  officer  corresponding  to  the  Public  Engineer  for  water-supply  who 
in  at  least  one  Continental  kingdom  (Wlirtemberg)  advises  local  authorities 
gratuitously  on  questions  of  water-supply,  and  who,  having  an  intimate 
knowledge  of  the  whole  water-supply  of  the  kingdom,  is  able  to  give  invalu- 
able information  and  advice,  and  whose  duty  it  is  to  see  that  economy  of  cost 
is  exercised.  In  all  schemes  for  the  furnishing  of  water  to  villages— and 
much  more  when  districts  or  towns  have  to  be  supplied — it  is  important  to 
have  regard  to  the  natural  water-sheds,  the  available  percentages  of  rainfall. 
and  the  quantity  of  the  movements  of  the  ground-water ;  and  these  data  can 
only  be  furnished  by  a  technically  skilled  officer,  whose  knowledge  extends 
much  beyond  the  requirements  of  one  particular  district. 

All  storage  reservoirs  should  be  well  protected  from  contamination  by 
cattle,  and  by  excreta  of  human  beings.  They  should  be  kept  free  from 
weeds,  some  of  which  may  communicate  an  unpleasant  taste  to  the  water  ; 
and  all  dead  and  decaying  vegetable  matter  is  more  or  less  injurious.  When 
in  the  neighbourhood  of  towns  and  factories,  the  reservoirs  should  be  covered, 
so  as  far  as  possible,  to  exclude  contamination  by  solid  particles  floating  in  the 
atmosphere.  The  strength  and  stability  of  reservoirs  are  matters  foreign  to 
the  scope  of  this  article. 

But  in  all  cases  before  a  public  supply  is  stored  in  covered  reservoirs  the 
water  should  be  subjected  to  a  process  of  clarification,  which  may  sometimes 
be  effected  by  simple  subsidence.  This  process  needs  in  the  great  majority 
of  cases,  however,  to  be  supplemented  by  filtration,  and  occasionally  by  a 
softening  process,  of  which  the  Porter- Clark  process  is  the  best.  These 
matters  will  be  again  touched  upon  hereafter. 

B.  Storage  of  Water  in  and  about  Habitations 

The  storage  of  Avater  in  and  about  a  dwelling-house  is  a  necessary  evil.  In 
rural  districts,  where  the  supply  is  from  wells,  such  storage  in  tanks  and 
cisterns  is  often  indispensable.  Such  tanks  and  cisterns  should  be  of  slate 
by  preference,  or,  failing  this,  of  iron  or  galvanised  iron.  The  zinc  of  gal- 
vanised iron  is,  however,  apt  to  become  detached,  or  even  dissolved  if  the 
water  is  soft.  A  non-corrodible  cement  may  be  used  for  coating  the  interiors 
of  iron  cisterns.  Zinc  cisterns  have  all  the  disadvantages  of  galvanised  iron, 
and  are  deficient  in  strength,  so  that  they  are  not  easily  cleaned  out  without 
damage  being  done  to  the  cistern.  Leaden  cisterns  are  permissible  only 
when  it  has  been  ascertained  that  the  water  to  be  stored  exerts  practically  no 
solvent  action  on  lead.  Cisterns  should  not  be  larger  than  is  necessary  ;  their 
contents  should,  if  possible,  be  renewed  daily,  and  at  all  events  frequently. 
They  should  be  covered  and  protected  from  all  sources  of  contamination  ;  they 
should  have  no  direct  communication  wdth  any  cesspool,  drain,  sink,  pri\y, 
or  water-closet.  All  storage  reservoirs  for  water  should  be  thoroughly 
cleansed  at  least  once  every  three  months. 

For  towns  the  question  of  the  relative  values  of  the  constant  and  inter- 
mittent systems  of  supply  is  most  important ;  but  the  preponderance  of  opinion 
is  undoubtedly  in  favour  of  the  constant  syst<em  as  best  securing  economy  of 


248  HYGIENE 

water,  purity,  palatability  and  coolness,  and  personal  and  domestic  cleanliness. 
In  a  no  distant  future  an  intermittent  supply  will,  it  may  be  hoped,  be 
regarded  as  an  anomaly. 

DISTRIBUTION 

Water,  in  whatever  manner  it  has  been  stored,  has  pjenerally  to  be  dis- 
tributed to  houses  by  means  of  closed  conduits  or  pipes  ;  and  usually  the 
'  head  '  or  pressure  requisite  for  its  distribution  is  obtained  by  gravitation, 
although  a  preliminary  pumping  into  special  storage  reservoirs  may  be 
requisite,  where  the  usual  storage  reservoir  is  situated  at  too  low  an  eleva- 
tion to  secure  the  pressure  necessary  to  raise  the  water  to  the  level  of  the 
highest  houses  in  the  district  to  be  supplied.  Wherever  possible,  this 
pumping  should  be  avoided  on  account  of  its  cost.  Pipes  used  for  conveying 
the  water  fi-om  the  reservoirs  to  streets  are  called  mains,  and  are  nowadays 
mostly  constructed  of  cast  iron,  which  is  sometimes  lined  with  cement  or 
some  kind  of  varnish-hke  material,  such  as  Angus  Smith's  bituminous 
varnish,  in  order  to  protect  the  pipes  from  corrosion.  From  the  street 
mains  the  water  is  conveyed  into  the  houses  by  means  of  subsidiary  and 
smaller  pipes,  termed  supply-pipes,  which  are  usually  of  lead.  Lead  is  the 
most  convenient  and  useful,  though  by  no  means  the  safest  metal  for  the 
construction  of  these  pipes,  and  generally  for  distributing  water  through 
houses  ;  and  in  the  end  it  is  perhaps  cheapest.  All  the  efforts  made  to  bring 
about  the  substitution  of  other  materials  for  lead  in  distributing  pipes  have 
met  with  only  very  partial  success.  The  strength  and  flexibiUty  of  leaden 
pipes,  the  ease  with  which  they  may  be  bent  and  adapted  to  recesses, 
and  soldered  together,  with  their  small  liability  to  leakage,  are  invaluable, 
and  go  far  to  counterbalance  its  liability  to  corrosion  in  the  vast  majority 
of  cases.  They  are,  however,  liable  to  corrosion  and  consequent  contamina- 
tion of  the  water  by  the  poisonous  metal  lead.  This  action  of  water  upon 
lead  will  be  again  adverted  to,  and  discussed  in  detail. 

The  only  kind  of  pipe  that  has  entered  into  serious  competition  with  the 
leaden  pipe  is  the  iron  pipe ;  although  a  variety  of  materials  have  been 
used,  such  as  tin,  lead  lined  with  tin,  tinned  copper,  galvanised  iron,  earth- 
enware, gutta-percha,  bituminised  paper,  &c.  All  these  have,  however, 
proved  to  be  more  or  less  failures.  Leaden  pipes  lined  with  tin  would  at 
first  sight  appear  to  be  the  most  promising  substitute  for  lead,  since  they 
combine  in  a  high  degree  the  flexibility  and  adaptability  of  this  metal,  and,  as 
has  been  supposed,  with  freedom  from  corrosion  of  tin.  Their  safety  as 
regards  protection  of  the  lead  from  the  influence  of  water  is  nevertheless 
illusory,  and  they  are  costly.  The  tin  is  hable  to  crack  when  the  pipe  is  bent, 
and  thus  the  lead  becomes  exposed,  and  being  in  contact  with  the  less  cor- 
rodible  metal  tin,  and  both  in  contact  with  a  saline  Uquid,  a  galvanic  couple  is 
established  ;  and  the  more  oxidisable  metal  (lead)  undergoes  solution.  Thus 
the  contact  with  tin  actually  hastens  the  corrosion  of  the  lead.  The  joints 
also,  when  made  with  lead  solder,  are  also  liable  to  corrosion,  and  the  pro- 
tective influence  is  thus  illusory.  Finally,  though  less  corrodible  than  lead, 
tin  is  acted  upon  by  ordinary  natural  waters  ;  and  pipes  of  block  tin,  when 
used  for  the  conveyance  of  water,  have  been  found  deeply  pitted  from  corrosion. 
But  it  is  generally  thought  that  tin- contaminated  water  is  less  harmful  than 
that  which  contains  lead,  though  accurate  observation  as  to  this  is  wanting. 
On  the  whole,  when  iron  pipes  can  be  used,  they  are  the  safest  from  a 
sanitary  point  of  view.  The  hning  of  them  with  zinc  (galvanising)  is  not 
often  of  much  use,  as  the  zinc  coating  is  generally  rather  quickly  removed 
by  soft  waters. 


WATER  249 


DOUBLE   SUPrLT 


It  is  sometimes  difficult  to  obtain  an  adequate  supply  of  water  sufficiently 
pure  to  meet  the  needs  of  a  community  for  all  puiposes  ;  and  under  such 
adverse  circumstances  it  has  been  proposed  to  have  a  double  supply,  one  of 
pure  water  for  drinking  and  cooking,  &c.,  and  another,  less  pure,  for  closets, 
■drains,  and  sewers.  So  long  as  the  impure  supply  is  under  control,  and  in 
limited  to  public  and  trade  purposes,  no  objections  can  be  raised,  except  on 
the  score  of  the  cost  of  distributing  a  double  supply.  But  for  household  use 
a  double  supply  must  be  deprecated.  In  a  house  the  supply  which  is  most 
copious  and  easily  accessible  will  generally  be  used  by  preference,  except  the 
impure  supply  be  foul  to  the  senses.  Common  household  experience  shows 
that  servants,  even  of  the  better  class,  will,  when  two  taps  are  side  by  side, 
draw  water  from  that  which  delivers  water  most  freely  (generally  that  from 
a  cistern,  where  one  tap  delivers  from  the  main  and  the  other  from  a  cistern). 
In  this  respect  the  majority  of  people  cannot  be  trusted  to  make  a  choice. 
A  double  supply  for  household  use  ought  not  to  be  adopted,  except  for  very 
cogent  reasons. 

PKEVENTION   OF   WASTE 

There  has  been  much  difference  of  opinion  as  to  the  respective  amounts 
of  waste  attending  the  adoption  of  the  two  opposing  systems  of  public  water- 
supply,  the  intermittent  and  the  constant  systems.  It  has  been  urged  as  an 
objection  to  the  general  adoption  of  the  constant  system  of  supply,  that 
where  an  unlimited  supply  of  water  is  at  all  times  obtainable  there  will  be 
.an  undue  use  of  water,  a  large  portion  of  the  water  taken  being  allow^ed  to 
run  to  waste.  Experience  under  the  intermittent  system  of  supply  has, 
singularly  enough,  furnished  fallacious  argum^ents  for  this  contention. 
Experience  under  the  constant  system  has  belied  the  above  unfounded 
conclusion.  It  is  not  found,  with  a  constant  supply,  that  it  is  altogether 
impossible  to  limit  the  consumption — or  rather  consumption  plus  waste — 
to  a  reasonable  amount.  On  the  contrary,  with  good  regulations,  vigilant 
inspection  of  cisterns,  waste-pipes,  and  taps,  waste  is  brought  within  reason- 
.able  limits,  and  the  undue  use  of  water  may  be  limited  in  other  direc- 
tions. To  large  water-consumers  the  supply  may  be  by  meter  ;  but  it  has 
not  hitherto  been  found  possible  to  supply  water  by  meter  in  all  cases. 
The  small  meters  sometimes  used  do  not  act  well,  and,  in  fact,  they  are  said 
to  allow  the  liquid  to  pass  through  them  unregistered.  The  same  cannot  be 
;said  of  large  meters.  At  all  events.  Water  Companies,  charging  rates,  appear 
to  have  an  invincible  repugnance  to  supplying  water  on  any  but  a  very  large 
scale  by  meter.  For  towns  the  preponderance  of  opinion  is  undoubtedly  in 
favour  of  the  constant  system,  as  best  securing  economy  of  water,  purity, 
palatability,  coolness,  and  personal  and  domestic  cleanliness.  A  prejudice 
was  created  against  the  constant  system  by  the  absurd  regulations  attempted 
to  be  introduced  so  as  to  prevent  waste,  such  as  the  dehvery  of  water  through 
minutely  constricted  pipes  so  that  the  water  would  issue  only  in  a  dribble. 
Such  regulations  are  impracticable,  and  dangerous  in  case  of  fire ;  and 
with  proper  supervision  it  is  found  that  the  substitution  of  a  constant 
for  an  intermittent  system  has  actually  resulted  in  the  saving  of  water. 
Indeed,  in  the  present  day,  the  relative  values  of  the  two  systems  can  hardly 
be  a  matter  of  dispute  ;  and  no  householder  who  has  experienced  the  comfort 
and  benefits  of  a  constant  supply  would  willingly  have  a  reversion  to  the 


2.:0  HYGIENE 

intermittent  system.  Even  for  villages — and  oftcner  for  groups  of  villages — 
a  constant  supply  is  nowadays  frequently  laid  on,  to  the  great  comfort  and 
advantages  of  rural  populations. 

The  recent  experience  of  London — now  in  part  having  a  constant 
supply — is  altogether  in  favour  of  the  constant  system,  and  shows  that  with 
moderate  inspection  no  midue  waste  or  cost  is  incurred.  Moreover,  meters 
have  been  devised  which  enable  the  water  companies  to  ascertain,  in  case  of 
need,  in  what  particular  districts  waste  or  consumption  is  going  on,  and 
thus  to  arrive  at  a  loiowledge  as  to  where  more  supervision  is  required.  Nor 
need  this  supervision  and  inspection  be  unduly  inquisitorial.  The  experience 
of  the  town  of  Blackburn  is,  in  this  respect,  instructive. 

In  the  New  World  the  intermittent  system  has  never  been  largely  intro- 
duced. But  it  nmst  be  admitted  that  the  figures  given  by  the  Boston 
(U.S.)  Water  Board  (Buck's  '  Hygiene,'  vol.  i.  p.  212)  of  the  several 
supplies  in  1879  of  water  to  eighteen  cities  of  the  United  States  show  that 
the  town  supplies  in  the  States  are  larger  than  in  England.  The  supplies 
there  stated  range  from  22  to  100  imperial  gallons  per  head  per  day,  with  an 
average  of  50  gallons,  or  about  50  per  cent.,  more  than  is  supplied  to  London. 
lUit  the  strict  comparison  of  places,  widely  differing  in  climate  and  the  habits 
of  the  peoples  inhabiting  them,  cannot  in  fairness  be  insisted  on. 


CLARIFICATION   OF  DEIXKING  WATER 

Spring-waters  and  well-waters  are  usually  sufficiently  clear  and  free  from 
deposit  to  need  no  adventitious  aid  to  render  them  acceptable  to  the  eye,, 
and  palatable.  Indeed,  such  waters,  when  clear,  are  best  delivered  direct  to 
the  consumers,  so  as  to  avoid  contamination  by  exposure  and  manipulation. 
It  is  otherwise  with  waters  collected  from  large  gathering  areas,  and  with 
river-waters.  These  both  commonly  contain  so  much  suspended  matter, 
and  are  so  much  discoloured,  as  to  necessitate  a  preliminary  treatment  in  order 
to  render  them  clear,  pellucid,  colourless,  and  free  from  objectionable  deposits. 
Hard  waters,  especially  those  from  springs,  and  less  often  river-waters,  may 
also  be  improved  in  appearance  and  better  fitted  for  domestic  and  manufac- 
turing purposes,  by  being  deprived  of  a  portion  of  their  mineral  constituents 
before  distribution  to  the  consumers.  This  is  best  done  by  the  Porter-Clark 
process. 

Claeification  by  Subsidence 

The  grosser  sohd  particles  suspended  in  upland  surface  waters,  and  in 
those  taken  from  rivers  and  lakes  during  times  of  flood,  are  often  readily, 
expeditiously,  and  cheaply  got  rid  of  by  simply  allowing  the  water  to  come 
to  rest  in  storage  reservoirs  for  a  variable  period  ;  but  finely  divided  clayey 
matter  is  not  thus  easily  removed,  and  may  remain  suspended  in  the  water 
for  days,  or  even  weeks.  A  signal  instance  of  the  self-clarification  of  a 
turbid  river  is  seen  in  the  case  of  the  water  of  the  river  Khone  during  its 
passage  through  the  Lake  of  Geneva,  which  acts  as  a  huge  subsidence  reser- 
voir in  which  the  highly  turbid  water  comes  to  comparative  rest.  Thus  the 
water  is  allowed  to  deposit  the  solid  suspended  matters  with  which  it  is  con- 
taminated on  its  entrance  into  the  lake  (see  p.  263,  _posi). 

In  the  waterworks  of  all  large  towns,  when  the  water  is  taken  from 
upland  collecting  grounds  or  from  streams — natural,  or,  failing  these,, 
artificial  reservoirs,  are  made  use  of,  so  as  to  at  least  partially  clarify  the 
water  before  it  is  subjected  to  subsequent  filtration.      When  discoloured 


WATER  251" 

peaty  upland  waters  are  stored  in  this  manner,  much  of  the  brown  discolora- 
tion is  got  rid  of,  and  it  is  said  that  the  deeper  the  reservoirs  the  more 
effectually  is  the  colour  removed.  Thus,  in  Loch  Katrine,  the  lake  which 
supplies  Glasgow  with  water,  the  brown  peaty  water  discharged  into  the  lake 
from  its  contributory  streams  loses  most  of  its  colour,  and  is  delivered  in 
Glasgow  in  a  practically  colourless  state.  It  has  been  supposed  that  the 
loss  of  colour  thus  undergone  on  storage  is  due  to  the  oxidation  which  peaty 
matter  undergoes  under  the  influence  of  light — oxidation  being  much  more 
active  under  the  influence  of  light  than  in  the  dark.  But  it  is  more  probaljle 
that,  although  oxidation  is  undeniable,  much  of  the  peaty  matter  in  water  is^ 
not  truly  dissolved,  but  is  in  a  minute  state  of  subdivision  which  enables  it 
to  remain  suspended,  and  that  these  fine  suspended  particles  subside  on 
standing.  The  fact  that  deep  reservoirs,  which  are  less  readily  aerated  with 
oxygen  than  shallow  ones,  are  more  efi'ective  than  the  latter  in  removing 
peaty  discoloration  is  against  the  oxidation  theory.  It  is  known  that 
during  the  bleaching  of  a  peaty  water  by  natural  processes,  a  brown  deposit 
subsides ;  but  whether  this  is  the  actual  discolouring  agent  in  the  water  or- 
an  oxidation  product  thereof,  is  undetermined. 

Deep  lakes  and  artificial  reservoirs  have  the  great  advantage  over 
shallow  ones  of  preserving  the  water  at  a  more  uniform  temperature,  neither- 
too  warm  in  summer  nor  too  low  in  winter  as  to  permit  of  freezing. 

Clarification  and  limited  purification  of  water  by  subsidence  appear  to 
have  been  known  to  and  practised  by  the  Eomans;  indeed  the  piscinae 
which  have  been  described  by  archaeologists  as  filtering  places,  appear  to- 
have  been  subsidence  tanks  of  special  and  ingenious  construction ;  and  we 
learn  that  they  were  not  always  successful,  but  that  turbid  water  was 
delivered  in  the  Imperial  City  during  times  of  flood. 

At  St.  Petersburg  the  waters  of  the  river  Neva  are  clarified,  and  ren- 
dered purer,  by  a  special  process,  the  water  being  caused  to  fall  in  successive 
cascades  each  of  a  couple  of  feet,  on  to  wire  gauze.  The  gauze  soon 
becomes  covered  with  a  black  scum,  although  the  water  before  this  treatment 
is  apparently  clear.  The  water  of  the  Neva  is  a  marsh-land  water  ;  and  the 
scum  is  supposed  to  be  formed  by  the  combined  effects  of  '  flocculation '  and 
oxidation  of  the  organic  constituents  of  the  river-water  ('  Proc.  Inst.  Civ.. 
Engineers,'  xxvii.  p.  46). 

FILTRATION 

The  clarification  of  a  town  water-supply  is  usually  supplemented  by 
filtration  ;  and  its  purification  is  also  to  a  certain  extent  effected  by  the  same 
means.  We  shall  consider  filtration  on  a  large  scale  as  carried  out  with 
large  supplies,  and  domestic  filtration,  i.e.  the  local  filtration  of  relatively 
small  quantities  of  water  in  habitations. 

On  a  large  scale,  water,  after  treatment  in  subsidence  reservoirs,  is  nearly 
always,  in  this  country  at  least,  filtered  through  sand  and  gravel.  No  great 
success  has  attended  the  attempts  to  substitute  other  materials  for  these,  or 
as  a  supplement  to  sand  and  gravel.  It  must  not  be  supposed  that  sand  acts- 
solely  as  a  mechanical  strainer ;  for  it  is  also  an  agent  in  achie-ving  the 
oxidation  of  organic  matter,  either  by  the  air  contained  within  its  pores,  or- 
more  probably  by  the  condensation  of  oxygen  on  its  surface  ;  for  all  finely- 
divided  solid  substances  have  this  power  of  condensing  oxygen.  In  this 
condensed  state,  oxygen  is  well  kno-wn  to  be  peculiarly  active  in  bringing^ 
about  oxidation.  Of  this  power  charcoal  in  a  minute  state  of  di-vision  is  & 
striking  instance.     Vegetable   charcoal   has  the  power,  when  ignited   and 


252  HYGIENE 

plunged  into  oxygen,  or  even  into  air,  of  absorbing  several  hundred  times  its 
volume  of  the  gas,  and  then  becomes  an  intense  oxygenant. 

As  ordinarily  constructed,  a  filter-bed  may  be  regarded  as  a  (J  -shaped 
tube,  with  a  long  and  a  short  limb,  the  longer  limb,  some  ten  feet  in  length, 
being  represented  by  the  bed  of  filtering  material  plus  the  superposed  unfil- 
tered  water.  The  filtered  water  (effluent  water)  collects  in  what  may  be  re- 
garded as  the  shorter  limb  of  the  tube.  The  water  is  forced  downwards 
through  the  filtering  material  by  a  head  or  pressure  of  water  represented  by 
the  difference  in  level  of  the  water  in  the  two  limbs  of  the  apparatus.  The 
filtering  medium  may  consist  of  a  stratum  of  fine  clean  sand,  two  feet  in  depth, 
followed  by  eighteen  inches  of  screened  gravel  of  various  sizes,  the  finest  being 
at  the  top  and  the  coarsest  at  the  bottom ;  and  below  this  there  may  be 
thirty  inches  of  broken  stones  of  two  sizes,  the  smallest  size  at  the  top. 
Thus  the  water  in  its  passage  downwards  meets  successively  with  filtering 
material  of  progressively  increasing  size  as  to  its  particles  and  the  magnitude 
of  the  interspaces.  The  topmost  layer  of  fine  sand  is  the  real  filtering 
medium. 

The  New  Eiver  Company's  filter-beds  are  constructed,  from  below  up- 
Avards,  of  six  inches  of  bricks,  followed  by  a  similar  thickness  of  gravel,  and 
on  the  top  of  this  a  layer  of  sand  thirty  inches  deep  ;  and  the  water  is  usually 
allowed  to  stand  to  a  depth  of  five  feet  on  the  top  of  the  filter-beds.  The 
water  percolates  downwards  at  about  the  rate  of  six  inches  per  hour  ;  or  half 
a  cubic  foot,  equal  to  'd}j  gallons,  passes  through  each  square  foot  of  surface  per 
hour,  or  14:  gallons  per  diem,  equivalent  to  180,000  gallons  nearly  per  acre  per 
hour.  This  rate  is  thought  by  some  authorities  to  be  excessive,  and  they 
would  put  the  maximum  permissible  rate  at  60,000  to  100,000  gallons  per 
acre  per  hour,  or  from  three  to  four  and  a  half  inches  of  downward  progres- 
sion per  hour. 

As  has  been  already  stated,  it  is  the  uppermost  layer  of  sand  which  is  the 
effective  purifying  material ;  and  this  layer  in  contact  with  the  main  body  of 
water  to  be  filtered  soon  becomes  foul  and  clogged,  so  that  the  filter-bed  has 
to  be  run  dry  and  its  upper  surface  scraped  pretty  frequently,  when  a  fresh  sur- 
face being  exposed  the  filter  is  again  set  in  action.  Thus  the  filter-beds  are 
worked  intermittently,  some  of  the  beds  being  always  undergoing  renovation. 
After  a  certain  quantity  of  the  sand  has  in  this  way  been  removed  by  succes- 
sive scrapings,  fresh  sand  must  be  placed  on  the  filter. 

Such  filters  as  have  been  described,  are  effectual  in  removing  all  suspended 
matters  from  the  water,  if  this  be  not  forced  through  the  filter-beds  too 
rapidly  by  excess  of  pressure.  The  rate  will  vary  according  to  the  character 
of  the  water  to  be  operated  on.  It  is  obvious  that  a  slightly  turbid  Avater  may 
be  filtered  with  safety  at  a  much  greater  rate  than  a  highly  turbid  water. 
Filtering  beds  vary  in  size  from  half  an  acre,  or  even  less,  up  to  four  acres. 
The  depth  of  water  over  the  filtering  material  may  be  four  or  five  feet ;  but 
the  actual  head  or  pressure  of  water — the  difference  of  level  between  the 
height  of  the  water  in  the  two  limbs  of  the  U-^ube — must  be  made  to  vary  : 
when  the  filter  is  clean  a  foot  or  less  of  head  or  pressure  will  suffice  ;  but  as 
the  filter  becomes  clogged  by  use,  a  greater  pressure  must  be  used,  else  the 
water  will  not  pass  through  the  filter  with  sufficient  rapidity.  It  must 
be  borne  in  mind  that  the  slower  the  filtration  the  more  effective  will  it  be 
in  purifying  the  water.  The  aim  of  the  engineer  is  of  course  to  filter  just  so 
much  water  per  hour  as  is  consistent  with  the  desired  degree  of  purity.  The 
rule  is  that  each  vertical  inch  of  water  passing  represents  half  a  gallon  nearly 
per  square  foot  of  surface,  or  22,700  gallons  per  acre  per  hour,  approxi- 
jmately — the  requisite  supply  for  about  UOO  people. 


WATEE  25a 

In  variable  climates  deep  filter-beds  are  best,  so  as  in  winter  to  Lave  a 
large  body  of  water  so  as  to  avoid  freezing ;  and  tlie  edge  of  the  water  must 
be  kept  free  from  ice,  in  order  to  obviate  the  outward  thrust  of  this  if  it 
forms,  else  the  masonry  of  the  walls  of  the  filter-beds  would  be  endangered. 
Deep  filter-beds  have  the  additional  advantage  of  keeping  the  water  cool  in 
summer  ;  but  they  have  also  the  disadvantage  of  greater  liability  to  stagna- 
tion than  those  which  are  shallower. 

The  filtered  water  should  be  stored  in  covered  reservoirs,  so  as  to  avoid 
contammation  with  dust ;  and  reservoirs  near  towns  are  usually  required  by 
statute  to  be  effectively  covered.  It  is  desirable  also  to  distribute  the  water 
from  the  reservoirs  through  closed  pipes  rather  than  through  open  conduits. 

Filtration  through  sand  alone  undoubtedly  does  more  than  simply  remove 
suspended  matters  and  living  organisms  :  organic  matters  are  oxidised,  and 
the  water  is  thus  much  improved  not  only  in  appearance  but  also  as  to  its 
purity.  Attempts  have  been  made  to  further  purify  waters  by  using  filter- 
beds  charged  with  charcoal,  spongy  iron,  partially  oxidised  scrap  iron,  &c. ; 
but  all  these  have  in  this  country  been  abandoned  in  practice.  They  are  too 
costly,  and  require  too  frequent  renewal  to  admit  of  their  profitable  adoption ; 
and  moreover  if  a  fairly  pure  v/ater- supply  be  adopted  (and  none  other  should 
be  used)  the  use  of  any  better  filtering  material  than  clean,  well-washed  sand 
is  not  called  for.  The  attempted  purification  for  drinking  purposes  of  organi- 
cally polluted  water  ought  to  be  deprecated.  An  essentially  bad  water  cannot 
be  turned  into  a  good  water  by  any  practically  available  process  of  simple 
filtration. 

The  Porter-Clark  process  is  an  admirable  one  for  removing  excess  of 
temporary  hardness,  and  the  carbonate  of  calcium  deposited  in  the  process 
carries  down  with  it  organic  matters,  so  that  the  filtered  water  is  fairly  soft, 
clear,  and  of  a  fine  blue  tint  when  viewed  in  thick  layers. 

Household  Filtbation 

Under  the  head  of  household  filters  may  be  placed  the  innumerable  filters 
which  have  been  introduced  for  filtering  water  immediately  before  its  use  in 
houses,  factories,  and  like  establishments. 

Where  water,  efficiently  filtered  on  a  large  scale,  is  distributed  direct  from 
the  storage  reservoirs  on  the  constant  system,  the  writer  is  of  opinion  that  it 
is  as  a  rule  best  to  draw  the  water  direct  from  the  main  supply-pipe,  and  to 
use  it  without  further  filtration.  But  where  the  water  is  supplied  on  the 
intermittent  system,  and  is  consequently  stored  in  household  cisterns,  it  is 
often  desirable  to  filter  it  before  use.  Also  in  times  of  epidemics  it  is  desir- 
able for  safety  to  boil  drinking  water  and  filter  it  before  use.  More  often  than 
not,  perhaps,  a  drinking  water  is  rendered  less  pure  by  ordinary  filtration  ; 
and  nearly  always  household  filters  are  placed  inmost  undesirable  situations, 
such  as  near  sinks,  in  pantries,  near  kitchens,  &c.  i.e.  in  impure  atmospheres. 
Under  these  conditions  the  water  is  apt  to  absorb  gases  and  vapours  which  give 
it  an  unpleasant  flavour ;  and  this  is  more  particularly  the  case  when  the 
water  is  boiled.  Boiling  water  when  cooled  in  an  impure  atmosphere  very 
quickly  absorbs  gases  and  vapours  ;  and  thus  it  is  notorious  that  water  which 
has  been  boiled  is  not  only  very  often  vapid  but  positively  nauseous  in  flavour. 

Notwithstanding  these  disparaging  remarks  as  to  domestic  filtration,  it 
must  be  admitted  that  there  are  circumstances  under  which  a  water  must  be 
filtered  in  order  to  render  it  wholesome.  Marshy  water,  taken  by  the  soldier 
on  the  march  from  doubtful  or  obviously  impure  sources,  and  soft  peaty 
waters  which  have  passed  through  leaden  pipes,  must  be  filtered. 


254  HYGIENE 

The  varieties  of  filtering  media  whicli  have  been  vised  are  innumerable  ; 
but  it  may  be  stated  generally  that  these  display  the  skill  of  the  inventor 
and  patentee  to  excess,  and  that  most  of  them  are  of  comparatively  httle  use 
with  regard  to  real  effective  purification. 

Fresh  burnt  animal  charcoal  is  perhaps  the  best  of  all  filtering  media, 
and  filters  chiefly  constructed  of  this  material  should  always  be  used  for 
lead-polluted  water-supplies.  The  experience  of  Mr.  A.  H.  Allen  with  the 
Shefiield  waters  is  to  the  effect  that  no  other  substance  is  nearly  so  efficacious 
as  animal  charcoal  for  removing  lead  from  water.  In  jMaignen's  '  Filtre 
Eapide,'  animal  charcoal  and  asbestos  cloth  are  used.  Vegetable  charcoal  is 
far  less  efficacious  than  animal  charcoal  as  a  purifying  agent.  Seaiveed 
charcoal  is  said  to  be  superior  to  ordinary  vegetable  charcoal  in  this  respect. 
The  great  defect  of  all  forms  of  charcoal  filters  is  that  they  speedily  become 
inefficacious,  and  the  charcoal  must  be  frequently  renewed  or  re-burnt,  else 
the  fouled  charcoal  will,  as  Dr.  Franklaud  has  shown,  actually  increase  the 
amount  of  organic  impurity  in  the  water.  Block-carbon  filters  (moulded 
•  carbon  blocks)  do  httle  more  than  remove  gross  suspended  particles,  are 
)nostly  useless,  and  should  not  be  used  except  when  no  better  filter  can  be  found, 
as  by  the  soldier  on  the  march,  to  whom  a  small  suction  filter  is  invaluable. 
Sponge  is  now  not  often  used.  It  merely  removes  suspended  particles, 
and  soon  clogs  and  becomes  foul.  Sponge  filters  require  constant  attention, 
and  frequent  cleaning  and  renewal.  Asbestos  is  a  much  better  material,  and 
•can  easily  be  re-burnt.     It  acts  only  mechanically. 

Porous  stone,  pumice,  and  ground  slag  (Chamois  Filter)  act  merely  as 
mechanical  filtering  media  ;  and  filters  constructed  of  these  materials  are 
not  very  serviceable. 

Spongy  iron  (Bischoff's  filter),  magnetic  carbide,  silicated  carbon,  and  car- 
bonised  ironstone  are  useful  filtering  materials,  which  act  mechanically  as 
strainers,  as  oxidisers  by  surface  condensation  of  oxygen,  and  also  perhaps  by 
electrolytic  action. 

Carferal  or  carbolite  (Creuse's  Service  Filter)  is  an  efficacious  filtering 
medium.  It  appears  to  be  made  from  clay  with  some  iron  and  carbon.  Its 
preparation  is  somewhat  of  a  secret.  Creuse's  filter  is  a  good  simple  one, 
and  easily  cleaned. 

The  Chamberland-Pasteur  Filter  is  perhaps  the  best  of  all  domestic 
filters.  Its  construction  is  very  simple,  for  it  merely  consists  of  a  tube  of 
fine  unglazed  biscuit  porcelain,  which  may  be  screwed  on  to  the  service 
tap,  when  the  pressure  of  the  water  will  force  the  fluid  through  the  pores 
of  the  porcelain,  and  a  fairly  rapid  rate  of  filtration  results.  It  is  most 
efficacious  m  removing  even  the  finest  suspended  particles,  for  even  the 
bacilh  of  anthrax  are  by  it  effectually  removed  from  water.  This  filter  acts 
purely  mechanically.  It  appears  to  be  inefficacious  for  the  removal  of  lead 
from  waters.  The  surface  of  the  porcelain  tube  in  a  short  time  becomes 
covered  with  a  slimy  coating,  even  when  an  apparently  clean  water  is  filtered. 
This  coating  is,  however,  readily  and  quickly  removed  by  removing  the  tube 
.and  brushing  it,  or  by  washing  it  with  hydrocliloric  acid. 


QUALITY   OF   WATEE 

In  their  Sixth  Eeport  the  Elvers  Pollution  Commissioners,  1868,  remarked 
that  in  respect  of  wholesomeness  and  general  fitness  for  drinking  and  cooking 
their  researches  led  them  to  the  following  classification  of  waters  in  the 
-order  of  their  excellence,  and  founded  upon  their  respective  sources  : 


"Wholesome   . 

.-2. 
3. 

Suspicious     . 

(5. 

Dangerous     . 

J6. 
17. 

WATER  255 

Spring- water \        Very 

Deep  well-water I    palatable. 

Upland  surface  water         .         .         .         .\  Moderately 

Stored  rain-water j    palatable. 

Surface  water  from  cultivated  land    .         . , 
Eiver-water  to  which  sew;i'j;G  gains  access.  [-  Palatable. 
Shallow  well-water  .         .         .         .         .j 

And  they  urged  that  preference  should  always  be  given  to  spring  and  deep 
"well-water  for  purely  domestic  purposes,  over  even  upland  surface  water,  not 
only  on  account  of  the  much  greater  intrinsic  purity  and  palatability  of 
these  waters,  but  also  because  their  physical  qualities  render  them  peculiarly 
valuable  for  domestic  supply,  since  they  are  almost  invariably  clear,  colourless, 
transparent,  and  brilliant ;  qualities  which  add  greatly  to  their  acceptability  as 
beverages,  whilst  their  uniformity  of  temperature  throughout  the  year  renders 
them  cool  and  refreshing  in  summer,  and  prevents  them  from  freezing  readily 
in  winter.  Their  inestimable  value  to  communities  in  these  respects  is, 
however,  in  some  degree  neutralised,  as  regards  temperature,  when  they  have 
to  be  stored,  and  too  often  the  qaantities  available  are  inadequate  to  supply  the 
needs  of  large  communities,  and  too  costly.  Hence  we  find  that  for  large  towns 
■upland  surface  water-supplies  are  now  being  largely  adopted  ;  as  witness 
Glasgow  from  Loch  Katrine,  Manchester  from  Lake  Thirlmere,  and  Liver- 
pool from  Lake  Vyrnwy.  Often,  too,  it  is  desirable,  and  more  especially 
in  the  case  of  a  manufacturing  population,  to  have  not  only  an  organically 
pure,  and  a  palatable,  but  also  a  soft  water-supply ;  and  here  the  advantage 
of  an  upland  surface  water  becomes  manifest,  as  appears  from  the  following 
classification,  according  to  the  Eivers  Pollution  Commissioners,  of  natural 
waters,  in  the  order,  of  their  softness  : 

1.  Eain- water. 

2.  Upland  surface  water. 

8.  Surface  water  from  cultivated  land. 

4.  Polluted  river-water. 

6.  Spring-water. 

6.  Deep  well-water. 

7.  Shallow  well-water. 

The  geological  strata  through  which  a  spring  or  deep  well-water  has  per- 
colated will  greatly  influence  its  palatability.  "Whilst  surface  waters  are 
often  vapid  and  tasteless  from  a  deficiency  of  carbon  dioxide,  or  have  a 
peaty  bitter  flavour,  in  percolating  through  deep  rocky  strata  organic 
matters  are  oxidised,  and  such  waters  are  often  highly  charged  with  carbon 
dioxide  gas,  which  renders  them  brisk  and  palatable.  The  waters  drawn  from 
deep  artesian  wells  in  the  Thames  basin  are  often  deficient  in  oxygen  and 
faintly  opalescent.  Some  also  contain  traces  of  sulphuretted  hydrogen,  and 
need  exposure  to  the  air  to  render  them  palatable  ;  whilst  others,  again,  when 
stored,  become  impregnated  with  confervoid  growths.  The  spring  waters  of 
the  magnesian  limestone  formation  are  not  only  excessively  hard,  but  con- 
tain such  a  proportion  of  magnesian  salts  as,  in  the  opinion  of  most  sanitary 
authorities,  renders  them  unfit  for  drinking  purposes.  A  pure  magnesian 
water  may,  nevertheless,  it  is  thought  by  many  sanitarians,  form  a  good 
water  for  domestic  use.  The  experiences  of  Sunderland  and  of  Bristol  are 
not  unfavourable  to  the  use  for  drinking  purposes  of  magnesian  waters. 

The  deep  well-waters  of  some  of  the  beds  of  the  New  Eed  Sandstone  are 
rich  in  sulphate  of  calcium,  as  well  as  in  chalk,  and,  though  palatable,  are 
excessively  hard. 


256  HYGIENE 

Of  far  more  importance  tlian  its  salinity  and  hardness  is  the  freedom  of 
a  drinking-water  from  contaminating  injurious  metals,  such  as  lead,  copper, 
and  chromium.  Salts  of  barium,  which  in  excess  are  i)oisonous,  and  in  small 
quantities  medicinal,  are  found  in  some  mineral  waters — e.g.  those  of  Har- 
rogate. The  influence  of  barium  compounds  in  minute  quantities  is  but 
little  known,  and  of  but  little  interest  to  the  sanitarian. 

Copper  compounds  are  injurious  when  habitually  ingested,  and  hence 
waters  containing  this  metal  ought  to  be  rejected. 

Chromium  salts,  especially  chromates,  act  as  virulent  poisons  even  when 
taken  in  small  quantities.  These  compounds  are  but  rarely  met  with  in 
waters,  and  exclusively  in  mining  districts. 

Chalybeate  waters — those  containing  iron  salts — are  nauseous,  stain 
linen,  and  are  unfitted  for  drinking  and  washing  purposes.  All  natural  waters, 
perhaps,  contain  some  small  trace  of  iron  compounds,  but  not  sufficient  to 
communicate  a  perceptible  flavour  to  the  water.  Chalybeate  waters  should, 
if  better  water  is  procurable,  be  rejected  as  unfitted  for  domestic  supplies. 

Of  vastly  more  importance  is  the  contamination  of  waters  by  lead.  Though 
the  corrosive  action  of  certain  w^aters  upon  lead  has  long  been  known,  and 
its  influence  recognised,  and  although  many  experimental  researches  have 
been  instituted  with  the  view  of  elucidating  this  action,  our  knowledge  of  the 
matter  is  still  confessedly  incomplete.  Pure  water,  deprived  of  gases,  has 
little  or  no  action  on  lead ;  when,  however,  tlic  water  contains  oxygen  the 
lead  is  rapidly  corroded  and  dissolved  ;  the  solvent  action  being  hastened,  if 
not  even  started,  by  the  presence  of  traces  of  carbonic  or  other  acid.  The 
lead  dissolved  appears  to  be  in  the  form  of  a  hydrate  (hydrated  oxide  of  lead). 
On  exposure  to  air,  the  dissolved  lead  is  soon  thrown  down  in  the  foi'm  of 
the  almost  insoluble  hydrocarbonate  (basic  carbonate  of  lead,  or  white  lead). 
The  deposit  is  very  finely  divided  and  has  very  little  coherence,  and  hence 
when  the  deposit  forms  on  the  surface  of  the  metal — as,  for  instance,  when 
there  is  simultaneous  oxidation  and  precipitation  of  the  lead  on  the  surface 
of  a  leaden  pipe — the  hydrocarbonate  does  not  protect  the  metal  beneath 
from  the  further  corroding  action  of  the  aerated  water.  Hence  pure  rain- 
water and  distilled  Avater  corrode  lead  with  great  rapidity.  If  a  few  grains 
per  gallon  of  sulphate  of  calcium  be  introduced  into  such  a  water,  an 
adherent  and  coherent  thin  grey  film  of  a  lead  compound  quickly  forms  on 
the  surface  of  the  metal,  and  the  water  subsequently  takes  up  a  quite  incon- 
siderable amount  of  lead  ;  and  thus  the  metal  is  preserved  from  further  cor- 
rosion. Other  earthy  salts  have  a  similar  effect.  Some  saline  bodies,  such  as 
nitrate  of  ammonium — a  constituent  of  ordinary  rain-water — increase  the 
solvent  action  of  water  upon  lead.  Carbonic  acid  diminishes  the  corrosive 
action  of  waters  on  lead,  probably  by  forming  the  insoluble  hydrocarbonate  ; 
but  an  excess  of  carbonic  acid,  under  increased  pressure,  increases  the  solvent 
action  of  the  water  ( Muir).  Hence  aerated  water  ( '  soda  water  ' )  is  exceedingly 
liable  to  become  contaminated  with  lead. 

It  has  been  asserted  that  carbonate  of  lead,  like  the  carbonates  of  calcium 
and  magnesium,  is  more  soluble  in  excess  of  carbonic  acid  than  in  water,  and 
that  a  bicarbonate  of  lead  is  formed  when  lead  is  present  in  solution  in  a 
water  containing  excess  of  carbonic  acid,  and  experimental  proof  of  this 
action  has  been  furnished. 

Among  the  many  substances  that  have  been  credited  with  increasing  the 
solvent  action  of  Avater  upon  lead  are — carbonic  acid  ;  free  mineral  acids  ; 
carbon  acids,  the  product  of  the  decay  of  vegetable  matters,  and  especially 
peat ;  organic  matters  ;  nitrates  and  nitrites  ;  and  chlorides — a  sufficiently 
extended  hst.     Among  the  substances  which  have  been  stated,  on  the  other 


WATER  257 

hand,  to  retard  corrosion  and  solution  are  carbonic  acid,  carbonate  of  calcium, 
sulphate  of  calcium,  phosphates,  and  silica,  or  rather  dissolved  silicic  acid 
(Odling,  Crookes,  and  Tidy).  Dr.  Tidy  asserts  that  waters  which  contain  less 
than  half  a  grain  per  gallon  of  dissolved  silica  act  freely  upon  lead,  whilst 
those  which  contain  more  than  half  a  grain  of  silica  per  gallon  do  not — except, 
perhaps,  under  exceptional  circumstances — dissolve  lead  to  any  appreciable 
or  injurious  degree  ;  and  he,  together  with  Drs.  Odling  and  Crookes,  have 
proposed  to  artificially  impregnate  waters  with  silica  when  they  contain  such 
a  deficient  quantity  as  to  render  them  operative.  They  advise  that  such 
deficiently  silicated  waters  should  be  run  over  broken  flints,  or  a  mixture  of 
flints  and  chalk,  or  limestone,  and  it  has  been  asserted  that  the  flints  are 
obviously  dissolved  during  the  process.  In  opposition  to  this,  the  writer, 
Dr.  Dupr6,  and  Mr.  A.  H.  Allen,  have  found  that  the  soft  waters  (e.g.  those 
of  Sheffield),  which  act  freely  and  injuriously  on  lead  are,  in  many  instances 
at  least  acid  in  reaction ;  and  that  the  acidity  may  be  due  to  the  presence 
of  fixed  organic  and  inorganic  acids,  or  both.  The  organic  acids  are  due  to 
the  oxidation  of  peat.  The  inorganic  acid  may  be  sulphuric,  arising  from 
the  influx  of  a  ferruginous  water  containing  a  ferrous  salt.  On  exposure  the 
ferrous  salt  oxidises  and  splits  up  into  an  insoluble  basic  ferric  salt,  and  free 
sulphuric  acid  or  an  acid  sulphate.  Such  waters,  when  run  over  a  weir  or 
along  a  conduit,  composed  of  broken  soft  limestone  or  chalk,  have  their 
acidity  neutralised  ;  they  take  up  a  small  quantity  of  carbonate  of  calcium, 
and  acquire  additional  hardness,  corresponding  to  the  excess  of  chalk  dis- 
solved beyond  that  consumed  in  neutralising  the  free  acid.  This  extra  hard- 
ness may  amount  to  a  degree  or  two  per  gallon.  The  soap-destroying  power 
of  the  salts  of  calcium,  formed  by  the  action  of  the  fixed  acids,  is  not  greater 
than  that  of  the  free  acids  neutralised. 

It  must  be  admitted  that  the  whole  subject  of  the  action  of  waters  upon 
lead,  and  its  prevention,  stands  in  need  of  further  elucidation  and  research ; 
and  although  we  may  in  some  particular  instances  be  able  to  account  for 
the  action  of  water  upon  this  metal,  the  same  explanation  entirely  fails  in 
other  cases.  Thus  the  writer  of  this  article  has  found  that  whilst  the 
addition  of  an  alkaline  sihcate  of  sodium  to  distilled  water  will  prevent  the 
corrosion  of  lead  by  the  water,  the  same  addition  in  other  cases,  under  other 
conditions,  may  fail  as  a  preventive.  Again,  it  is  not  only  soft  waters 
exclusively  that  act  on  lead,  for  many  hard  waters  will  have  the  same  effect. 
Neither  the  silica  theory,  nor  the  acid  theory,  of  the  action  of  waters  upon 
lead,  accounts  for  the  whole  facts  known ;  and  of  two  apparently  similar 
waters  as  to  constituents,  one  will  act  vigorously  upon  lead,  whilst  the  other 
may  have  little  or  no  effect  in  dissolving  the  metal. 

Mr.  W.  H.  Power,  having  regard  to  the  observed  influence  of  acidity  on 
the  solvent  actions  of  soft  moorland  waters  on  lead,  offers  the  suggestion  that 
the  '  inscrutable  behaviour '  of  these  waters  in  regard  to  plumbo-solvent 
ability  may  be  related  to  the  agency,  direct  or  indirect,  of  low  forms  of 
organic  life.  This  suggestion,  no  doubt,  has  as  its  basis  the  circumstance 
that  certain  bacteria  have  been  found  experimentally  to  produce  acid  changes 
in  the  culture  media  in  which  they  have  been  grown  ;  but  the  results  hitherto 
obtained  with  the  Sheffield  plumbo-solvent  waters  are  mostly  negative 
(Eeports  of  the  Medical  Officer  of  the  Local  Government  Board  for  1887  and 
1888,  pp.  280  and  453  respectively). 

The  experience  of  Sheffield,  Keighley,  and  other  English  towns  has  been 

repeated  at  Dessau  in  Germany.     The  water-supply  of  this  town  was  free 

from  lead  before  distribution,  yet  92  cases  of  lead-poisoning  occurred  within 

a  short  time,  and  it  was  then  found  that  the  water  took  up  lead  from  the 

VOL.  I.  s 


258  HYGIENE 

house-pipes ;  and  the  water  first  drawn  after  standing  in  these  was  found 
to  contain  0-3  grain  of  lead  per  gallon.  It  was  also  found  that  when  tin 
was  introduced  into  the  pipes,  the  solvent  action  of  the  water  on  the  lead 
was  increased.  It  was  finally  concluded  that  the  mischief  was  due  to  the  want 
of  hardness  in  the  water  itself,  which  was  only  equal  to  3°  to  3"-4  of  Clark's 
scale.  By  increasing  the  hardness  to  0°  or  7°-2,  by  the  use  of  powdered 
limestone,  the  mischief  was  remedied.  It  is  stated  that  this  result  was  due, 
not  to  the  increase  of  hardness,  but  to  the  removal  of  carbonic  acid,  the 
absence  of  which  rendered  the  water  incapable  of  acting  on  lead. 

The  processes  for  preventing  access  of  lead  to  the  stomach  through  the 
xuedium  of  drinking  water  may  be  divided  into  three  groups,  namely  :  (1) 
processes  for  preventing  the  water  from  dissolving  lead  ;  as  an  example  of 
such  treatment,  we  may  mention  the  addition  of  lime  to  the  water,  whereby 
free  acids  are  neutrahsed,  and  their  solveut  action  upon  lead  avoided;  (2) 
processes  for  avoiding  contact  of  the  water  with  lead  ;  for  example,  by  using 
slate  or  galvanised  iron  cisterns,  and  glass-lined  or  tin-lined  pipes;  and 
(3)  processes  for  removing  lead  from  the  water  after  it  has  been  dissolved 
thereby ;  as  examples  of  which  filtration  through  compressed  carbon,  sand, 
.&c.  may  be  instanced.  Mr.  Eaton  estimated  the  cost  of  treating  the 
Sheffield  water  so  as  to  avoid  any  solvent  action  upon  lead  at  20,000Z.,  with 
an  annual  expenditure  of  350Z.  to  maintain  efficiency.  The  Sheffield  water 
contains  free  acid,  and  limestone  has  been  found  a  preventive.  Clearly  it  is 
more  satisfactory  to  strike  the  evil  at  its  root  by  treating  the  water  in  such 
a  way  before  it  gains  access  to  the  poisonous  metal  as  to  prevent  it  from 
being  contaminated  thereby,  than  to  trust  to  measures  for  preventing  contact 
ivith  the  metal,  or  for  removing  it  after  it  has  been  dissolved  in  the  water. 


EFFECTS   OF   HAEDNESS   OF   WATEE  USED   FOE  DEINKIXG  AND 
OTHEE  DOMESTIC   PUEPOSES. 

Very  different  opinions  are  held  as  to  the  injurious  or  non-injurious 
effects  of  the  use  of  hard  waters  for  domestic  supphes.  Up  to  some  fifty 
years  ago  scarcely  a  suspicion  appears  to  have  been  entertained  that  such 
waters  might  injure  health,  however  unpleasant  their  use  might  be  for 
detergent  purposes.  The  researches  of  the  late  Dr.  Clark,  of  Aberdeen,  on 
the  hardness  of  water,  its  estimation,  and  above  all,  the  introduction  of  his 
now  widely-known  process  for  softening  waters,  drew  attention  to  the 
subject ;  so  that  in  1850  the  General  Board  of  Health  arrived  at  the  sweep- 
ing conclusion  that  whilst  '  Thames  water  (of  about  14°  of  hardness)  taken 
up  beyond  the  influence  of  the  metropolitan  drainage,  and  filtered,  may  be 
used  without  injury  to  the  public  health  and  may  be  employed  temporarily 
until  other  sources  can  be  laid  under  contribution ;  we  advise  that  Thames 
water  and  other  water  of  like  quality  as  to  hardness,  be  as  early  as  practicable 
abandoned '  (quoted  in  '  Eeport :  Eoyal  Commission  on  AVater-supply,'  p.  xxiv. 
1869)  ;  and,  '  that  the  presence  of  lime  and  other  mineral  matter  deteriorates 
the  wholesomeness  and  value  of  the  water  for  the  purpose  of  drinking' 
{ibid.  p.  Ixiii.).  This  Eeport  was,  however,  not  endorsed  by  the  subsequent 
Scientific  Commission  of  1851,  consisting  of  the  three  eminent  chemists, 
Graham,  Miller,  and  Hofmann,  appointed  to  consider  it;  and  they  went  so  far 
as  to  enunciate  an  opposite  view.  They  said  (p.  Ixiii.) :  '  It  may  be  safely 
asserted  that  no  sufficient  grounds  exist  for  believing  that  the  mineral 
contents  of  the  waters  supplied  to  London  are  injurious  to  health.  No 
reasonable  doubt,  indeed,  can  be  entertained  of  their  salubrity.     The  shallow 


WATER  259 

well  waters  of  London  vary  from  32°  to  80°  of  hardness,  yet  these  waters 
have  never  been  pronounced  unwholesome  (i.e.  on  account  of  their  mineral 
constituents. — Ed.).  .  .  .  The  only  observations,  from  which  an  interference 
of  Hme  in  water,  in  deranging  the  processes  of  digestion  and  assimilation  in 
susceptible  constitutions,  has  been  conjecturally  inferred,  have  been  made 
upon  waters  containing  much  sulphate  of  Hme  and  magnesia.' 

Dr.  Letheby  considered  a  moderately  hard  water  best  for  drinking 
purposes,  and  for  the  general  supply  of  cities.  Mr.  Thomas  Ilawksley,  the 
engineer,  states  from  his  vast  personal  experience,  that  there  are  quite  as 
many  fine-raced  people  Hving  in  hard-water  districts  as  there  are  living  in 
soft-water  districts  ;  and  that  quite  80  per  cent,  of  the  whole  surface  of  the 
^lobe  yields  hard  water.  Sir  John  Simon,  Dr.  Miller,  Dr.  Frankland,  Dr. 
Odling,  and  Sir  Benjamin  Brodie,  have  all  expressed  their  opinions  that 
hard  waters — up  to  20°  of  hardness  at  least — are  not  injurious  to  health. 
Dr.  Edward  Parkes  was  of  opinion  that  a  hardness  of  over  10°  or  12°  might 
be  injurious. 

There  is  no  doubt  that  medical  opinion  has  undergone  some  change  as 
to  the  alleged  unwholesomeness  of  hard  waters ;  and  it  is  now  generally 
accepted  that  excessively  hard  waters  are  injurious  to  the  digestive  processes, 
though  proof  of  this  is  difficult ;  and  the  conclusion  has  been  doubted. 
Ooitre  and  glandular  swellings,  as  well  as  the  prevalence  of  urinary  calculi 
in  certain  districts,  are  associated  with  the  use  of  hard  waters.  All  are 
agreed  that  where  the  hardness  of  a  water  is  due  to  the  presence  of  carbonate 
of  calcium,  and  to  a  lesser  degree  of  carbonate  of  magnesium,  i.e.  when  the 
hardness  is  temporary  or  removable,  little  harm  ensues  ;  but  that  when  the 
hardness  is  permanent,  and  due  to  the  presence  of  the  sulphates,  nitrates,  and 
chlorides  of  calcium  and  magnesium,  tlie  dietetic  value  of  a  water  is  greatly 
impaired.  How  far  this  opinion  is  based  upon  a  solid  basis  of  facts  is  at 
least  uncertain.  The  waters  of  the  valley  of  the  Eiver  Trent,  and  very 
many  of  those  derived  from  wells  and  springs  in  the  New  Eed  Sandstone 
formation,  are  intensely  seleniferous,  i.e.  abound  in  sulphate  of  calcium,  and 
yet  are  not  generally  considered  harmful.  Some  of  our  town  supplies,  as 
e.g.  those  of  Bristol  and  Sunderland,  are  very  hard,  the  water  supplied  to 
Sunderland  containing  magnesia  and  sulphates,  the  equivalent  of  14  grains 
anhydrous  and  28  grains  crystallised  sulphate  of  magnesium  per  gallon; 
yet  the  Medical  Officer  of  Health  has  not  been  able  to  trace  any  inconve- 
nience to  health,  much  less  disease,  to  its  use,  and  it  is  believed  to  be  a 
good  wholesome  water,  though  having  a  hardness  of  25°. 

As  has  already  been  stated,  goitre  and  cretinism  have  been  attributed  to 
the  habitual  drinking  of  excessively  hard  water.  Eminent  medical  autho- 
rities have,  however,  dissented  from  this  conclusion  ;  very  hard  waters  are, 
it  is  true,  found  as  a  rule  in  districts  where  goitre  prevails ;  but  the  water- 
supply  is  only  one  among  many  conditions  shared  by  such  localities  in 
common ;  and  it  is  alleged  that  of  the  inhabitants  of  two  sides  of  a  valley 
with  practically  identical  water-supplies  as  to  hardness,  those  on  one  side  of 
the  valley  will  suffer  from  goitre,  whilst  those  on  the  other  side  will  be 
exempt  from  the  disease. 

For  most  culinary  purposes  a  hard  water  is  objectionable,  and  the  presence 
of  calcium  salts  is  said  to  harden  the  fibre  of  meat  during  boiling.  Sulphate 
of  calcium,  too,  when  boiled  with  leguminous  seeds,  is  asserted  to  form  hard 
indigestible  compounds  with  the  legumin  which  they  contain.  But  the  evidence 
as  to  this  is  not  very  conclusive.  Generally  a  chalky  water  is  quickly  and 
greatly  softened  by  boiling,  or  by  heating  it  simply  to  the  boiling  point ;  the 
carbonate  of  calcium  held  in  solution  by  excess  of  carbonic  acid  being  pre- 

s2 


260  HYGIENE 

cipitated  in  consequence  of  the  escape  of  carbon  dioxide  gas  at  the  boiling, 
temperature.  The  Chemical  Commission  of  1851  ('  Quart.  Jour.  Chem.  Soc' 
vol.  iv.  p.  388, 1852)  found  that  the  water  supplied  by  the  New  Eiver  Company 
to  London,  having  a  total  hardness  of  14°  to  15°  and  a  permanent  hardness 
of  about  2°,  when  drawn  on  six  different  occasions  from  the  fixed  boiler  of 
a  kitchen  range,  had  a  hardness  of  5°-4,  4°'9,  4°-l,  4°-l,  4°-9,  and  5°-8  ;  the 
average  being  4°*8,  or  one-third  of  the  original  amount.  In  tea-making,  hard 
water  is  thought  by  connoisseurs  to  yield  a  more  delicate  infusion  than  soft 
water,  and  is  hence  preferred.  A  soft  water,  on  the  other  hand,  yields  with  tea 
a  darker  and  bitter  infusion,  and  is  hence  more  esteemed  for  the  purpose  by 
the  lower  orders,  who  desiderate  '  strength  '  of  tea.  The  chief  difference  in 
this  respect  between  a  hard  and  a  soft  water  is  that  when  a  hard  water  is 
used  a  longer  time  is  required  for  the  infusion  of  the  tea. 

For  washing  and  for  manufacturing  purposes  a  soft  is  undoubtedly  pre- 
ferable to  a  hard  water,  except  in  brewing.  The  relative  values  of  waters 
for  washing  purposes  is  a  much  more  important  consideration  for  a  health 
officer  than  their  utihties  for  the  purposes  of  the  manufacturer.  Never- 
theless, in  towns,  the  latter  cannot,  for  economic  reasons,  be  altogether 
disregarded.  The  Chemical  Commission  of  1851  {ojJ.  cit.)  stated  (and  the 
statement  holds  good  in  the  present  day)  that  the  softer  the  water  the  better 
is  it  adapted  for  washing  with  soap ;  the  earthy  salts  present  causing  a 
definite  and  calculable  loss  of  soap,  which  may  be  taken  as  amounting,  with 
every  gallon  of  water  used  in  washing,  to  10  grains  of  soap  for  each  degree 
of  hardness  of  water.  But  such  data  are  not  alone  sufficient  for  calculating 
the  saving  of  soap  effected  by  the  use  of  a  soft  in  preference  to  a  hard  water ; 
for  soap  is  used  in  washing  not  merely  in  quantity  sufficient  to  soften  the 
water,  but  in  excess  to  act  as  a  detergent.  The  data  to  determine  the  pro- 
blem how  great  is  the  proportion  of  soap  lost  in  softening,  compared  with 
the  proportion  profitably  used  for  washing,  are  not  easily  obtained.  It  has, 
however,  been  ascertained  that  in  the  washing  of  woollens  2  oz.  of  soap 
per  gallon  is  required  ;  and  in  the  soaping  of  dyed  goods— a  process  analogous 
to  common  washmg — 0*45  oz.  only  per  gallon.  "With  boiled  Thames  water 
of  5°  of  hardness,  these  quantities  would  be  increased  to  2'11  and  0'5G  oz. ; 
or  the  quantities  of  soap  required  with  a  soft  water  are  increased  by  6 
and  25  per  cent,  respectively.  When  cold  water  of  16°  of  hardness  is  used, 
the  quantities  of  soap  consumed  in  washing  will  be  0'32  oz.  per  gallon  in 
excess  of  that  used  with  soft  water. 

When  soda  is  used  in  addition  to  soap,  as  in  ordinary  laundry  work,  the 
loss  of  soap  is  much  less,  since  the  soda  (carbonate  of  sodium)  precipitates 
the  calcium  salts  in  a  form  which  prevents  the  destruction  of  soap. 

The  money  loss  involved  in  the  use  of  hard  water  has  been  much  exag- 
gerated. The  difference  between  the  use  of  water  of  2°  and  one  of  14°  of 
hardness  is  about  128  grains  of  yellow  soap  per  gallon,  or  1^  oz.  per  6 
gallons,  6  gallons  being  the  ordinary  consumption  of  water  per  head  per  day 
for  washing  purposes  ;  it  being  assumed  that  the  water  is  used  cold.  The 
money  value  of  this  amount  of  soap  is  O-OAd.  ;  whilst  the  cost  of  softening 
35  gallons  of  water — the  daily  supply  per  head  in  towns — by  the  Porter- 
Clark  process  is  0-012d.  only.  The  difference  is  equal  to  rather  more  than 
lO^d.  per  head  per  annum. 

The  case  against  the  use  of  hard  water  was  ably  put  by  the  Chemical 
Commission  of  1881  {op.  cit.),  who  stated  that  it  is  in  the  more  careful 
washing  for  the  upper  and  middle  classes  that  the  advantages  of  soft  water 
become  fuUy  sensible  ;  for  when  a  hard  water  is  heated  the  carbonate  of 
calcium  is  precipitated  on  the  linen,  carrying  down  with  it  the  colouring 


WATER  261 

matter  of  the  dirty  water,  and  producing  stains  which  there  is  the  greatest 
difficulty  in  afterwards  removing  from  the  Hnen,  The  colouring  matter 
from  the  water  is  thus  indeed  fixed  upon  the  cloth  by  the  precipitated  calcium 
salt  with  the  tenacity  of  a  mordant.  The  evil  of  the  hardness  of  the  water 
is  also  aggravated  by  the  flood  tinge  of  chalky  river  waters.  The  Commis- 
sioners further  stated  that  the  saving  of  soap  by  the  use  of  soft  water  is 
most  obvious  in  the  washing  of  the  person ;  and  for  baths  soft  water  is 
undoubtedly  most  agreeable  and  beneficial.  Its  superior  efficiency  to  hard 
water  in  washing  floors  and  walls  is  calculated  also  to  promote  greater 
cleanliness  in  the  dwellings  of  all  classes,  both  within  doors  and  externally ; 
whilst  in  the  occasional  domestic  washing  of  linen,  the  smaller  preparation 
necessary  for  washing  in  soft  as  compared  with  hard  water,  the  saving  of 
soap,  and  the  more  easy  and  agreeable  nature  of  the  operation,  make  a  supply 
of  soft  water  in  a  high  degree  desirable.  The  saving  of  labour  is  also  con- 
siderable, and  tends  to  promote  cleanliness. 

At  a  later  date  the  Eoyal  Commission  on  Water  Supply,  1869  ('  Eeport,' 
p.  Ixxi.)  thus  fairly  summarised  the  arguments  for  and  against  hard  and 
soft  waters  as  public  supplies  for  London  :— 

'  There  is  no  doubt  that  the  evidence  is  conclusive  and  cogent  as  to  the 
great  advantage  of  soft  water  over  hard  for  washing,  and,  with  some  few 
■exceptions,  for  general  manufacturing  purposes  ;  and  if  we  were  treating  of 
the  supply  of  a  town  like  those  in  the  manufacturing  districts  of  England, 
where  large  quantities  are  required  for  these  purposes,  the  objection  to  the 
present  supply  (to  London)  would  assume  a  more  serious  aspect.  But  the 
amount  of  manufacturing  industry  in  the  metropolis,  of  a  kind  to  demand  a 
large  supply  of  soft  water,  is  exceedingly  small  in  proportion  to  the  popula- 
tion, and  it  must  be  recollected  that  the  softening  influence  of  boiling  largely 
diminishes  the  evil.  To  these  exceptional  cases,  also,  the  softening  process 
of  Dr.  Clark  would  be  easily  applicable. 

'  There  is  no  doubt,  also,  that  in  personal  ablutions  and  washing  generally 
the  use  of  soft  water  is  more  pleasant  and  economical,  but  we  think  the 
latter  advantage  has  been  much  over-estimated.  The  soap  is  usually  applied 
out  of  the  water,  and  therefore  it  is  with  the  small  quantity  of  water  adherent 
to  the  object  washed  that  we  have  to  deal,  and  not  with  the  total  quantity 
used  for  rinsing  to  remove  the  soap.  It  is  certain,  however,  that  when  a 
soft  water  or  rain-water  can  be  obtained  for  these  purposes  it  will  always  be 
preferred. 

'  On  the  whole  we  cannot  see  that  the  advantages  of  soft  water  .... 
are  of  sufficient  importance  to  justify  going  to  a  great  distance  to  obtain  it, 
in  place  of  the  ample  supply  near  at  hand.' 

To  this  the  writer  would  add  that  the  greater  danger  of  lead  contami- 
nation, often  introduced  by  the  adoption  of  a  soft  and  slightly  acid  water- 
supply,  may  far  outweigh,  from  a  hygienic  point  of  view,  the  disadvantages 
resulting  from  the  use  of  a  water  of  moderate  hardness. 

There  is  another  aspect  of  the  question  of  soft  verstis  hard  water  which, 
all-important  to  the  manufacturer,  is  not  without  an  important  bearing  upon 
domestic  supplies  for  a  highly  civilised  and  luxurious  people.  When  a  chalky 
water  is  boiled,  we  have  said  that  carbon  dioxide  is  expelled  and  carbonates 
of  calcium  and  of  magnesium  are  thrown  down.  Sulphate  of  calcium,  how- 
■ever,  remains  in  solution  if  the  water  be  boiled  under  ordinary  atmospheric 
pressure  ;  hence  the  deposit,  or  '  fur,'  which  in  household  boilers  is  mostly 
•composed  of  carbonate  of  calcium,  and  is  soft,  pulverulent,  and  for  the  most 
part  easily  detached.  But  sulphate  of  calcium  has  its  maximum  solu- 
bility at  95°  F.,  at  which  temperature  a  gallon  of  water  is  capable  of  retaining 


262  HYGIENE 

in  solution  178  grains  of  sulphate  of  calcium.  But  as  the  water  becomes 
more  saline  by  evaporation,  the  sulphate  of  calcium  becomes  less  soluble.  The 
same  result  ensues  if  the  water  be  heated  under  pressure  much  above  212°  F. 
(100°  C.)  Sulphate  of  calcium  is  quite  insoluble  in  a  boiling  solution  of  salt 
(brine)  of  sp.  gr,  1-033,  and  in  boilmg  water  at  a  temperature  of  284°- 
302°  F.  (140°-150°  C.)  Hence  the  difiiculties  involved  in  the  distillation  of 
sea-water,  in  the  use  of  sea-water  in  marine  boilers,  and  in  the  use  of  water 
containing  sulphate  of  calcium  in  boilers  under  pressure.  Under  these 
cu'cunistances  the  hard  furs  which  form  on  heating  the  water  consist  chiefly 
of  sulphate  of  calcium. 

The  Rivers'  Pollution  Commissioners,  in  their  sixth  report,  thus  classify 
water  according  to  their  softness  :  1.  Rain-water  ;  2.  Upland  Surface  water; 
3.  Surface  water  from  cultivated  land ;  4.  River-water  ;  5.  Spring-water ; 
6.  Deep  well-water  ;  7.  Shallow  well-water. 

The  following,  according  to  the  Commissioners,  are  the  chief  British  for- 
mations which  yield,  as  a  rule,  soft  waters  :  Ligneous;  2.  Metamorphic  ; 
3.  Cambrian  ;  4.  Silurian  (non-calcareous)  ;  5.  Devonian  (non-calcareous) ;  0. 
Millstone  Grit ;  7.  Non-calcareous  of  the  Coal-measures  ;  8.  Lower  Greensand ; 
9.  London  and  Oxford  Clay ;  10.  Bagshot  Beds ;  11.  Non-calcareous  gravel. 

On  the  other  hand,  the  following  geological  formations  almost  invariably 
yield  hard  Avaters  :  1.  Calcareous  Silurian ;  2.  Calcareous  Devonian  ;  3. 
Mountain  limestone ;  4.  Calcareous  rocks  of  the  Coal-measures  ;  5.  New- 
Red  Sandstone ;  6.  Conglomerate  Sandstone ;  7.  Lias ;  8.  Oolites ;  9. 
Upper  Greensand  ;   10.  Chalk. 


POLLUTION  OF  WATER  BY  ORGANIC  MATTERS 

The  pollution  of  water-supplies  by  solid  and  liquid  refuse,  such  as  sewage,, 
slop- water,  &c.,  is  all-important  from  the  health  point  of  view.  The  facts, 
so  far  as  they  are  known,  relative  to  the  pollution  of  water-supphes  by 
soakage  of  filth  are  as  follows  :  Sewage,  when  deposited  on  the  surface  of 
an  ordinary  cultivated  soil,  percolates  slowly  or  quickly  into  the  subsoil, 
according  to  the  less  or  greater  porosity  of  the  soil.  Whilst  percolating  it 
becomes  nitrified,  through  the  agency  of  organisms  which  have  recently  been 
identified  ('  Trans.  Roy.  Soc'  1890,  p.  107).  According  to  Mr.  Warrington  this 
nitrif}'ing  action  is  chiefly  exercised  m  the  more  superficial  layers  of  the  soil,, 
the  action  practically  ceasing  at  18  inches  below  the  surface.  If  the 
organic  matter  is  in  excess,  or  if  the  soil  be  persistently  swamped  with 
sewage,  nitrification  ceases.  The  nitrifying  process  renders  the  nitrogenous- 
matters  harmless  and  fitted  for  the  needs  of  growing  plants,  which  absorb 
and  utilise  the  nitrates.  When  sewage  is  discharged  in  excessive  quantities 
on  the  surface  of  a  porous  soil,  it  quickly  percolates  through  this  until  it 
meets  with  an  impervious  stratum  which  arrests  its  downward  course.  A 
shallow  or  surface  well  sunk  into  the  porous  soil  will  draw  no  water 
until  it  reaches  the  stratum  of  underground  water.  Into  this  the  liquid 
soaking  from  leaky  sewers,  drains,  and  cesspits  will  find  its  way  more 
readily  than  the  surface  water.  When  water  is  pumped  from  such  a  well 
the  level  of  the  water  in  this  is  depressed,  and  so  also  is  the  level  of  the 
underground  water  in  its  neighbourhood,  and  assumes  the  form  of  a  hollow 
inverted  cone,  so  that  any  soakage  through  the  soil  of  liquid  filth,  or  from  a 
drain  or  cesspool,  -will  inevitably  be  drawn  by  the  afflux  of  fluid,  according  to 
the  laws  of  hydrostatics,  towards  the  bottom  of  the  cone — i.e.  towards  the- 
well.     The  distance  through  which  the  hollow  inverted  cone  will  extend  or 


WATER  2G3 

make  itself  felt  will  vary  according  to  the  greater  or  less  porosity  of  the  soil, 
and  may  extend  to  from  15  to  160  times  the  depth  of  the  cone.  In  other 
words,  if  the  level  of  the  water  in  a  shallow  well  be  reduced  by  pumping, 
say  2  feet,  water  will  be  aspirated  into  the  well  from  a  distance  of 
15  X  2  =:  30  feet  as  a  minimum,  to  IGO  x  2  =  320  feet  as  a  maximum. 
The  set  or  current  of  the  underground  water  in  the  neighbourhood  of  a 
pumped  well  must,  indeed,  always  be  towards  the  well ;  and  it  is  by  the 
suction  exerted  on  cesspools  situated  in  proximity  to  wells  that  they  are 
emptied  when  these  are  pumped.  Hence,  in  one  sense,  the  more  a  well  is 
pumped  the  greater  its  liability  to  contamination  from  neighbouring  sources 
of  pollution.  The  action  of  wells  in  use  may  sometimes  greatly  divert  the 
course  of  underground  water,  which  but  for  the  action  of  wells  would 
always  be  towards  a  lower  level  and  towards  a  stream.  The  course  of  under- 
ground water  is,  indeed,  precisely  like  that  of  surface  water — towards  the 
lowest  available  level ;  only  the  slope  or  declivity  of  underground  is  less 
steep  than  that  of  surface  water,  in  consequence  of  the  greater  retarding 
influence  of  friction  in  its  passage  through  the  subsoil. 

For  the  reasons  just  now  assigned,  a  surface  well  can  never  be  safe,  hoAV- 
ever  well  its  sides  are  cased  and  made  impervious,  if  there  is  any  pollution 
of  the  soil  within  the  distance  to  which  the  inverted  cone  already  described 
extends.  Contaminated  water  will  be  drawn  into  the  bottom  of  the  well. 
The  only  real  protection  is  to  sink  the  well  through  the  first  impervious 
layer  of  soil,  and  to  cement  the  sides  throughout  to  a  point  below  the 
impervious  stratum,  so  as  to  draw  water  from  the  deeper  strata,  and  to 
protect  this  water  from  the  more  superficial  polluted  surface  water.  This 
plan  is  too  commonly  not  adopted  because  an  abundance  of  water  is  reached 
before  the  first  impervious  stratum  of  soil  is  reached,  and  at  a  small  depth. 
It  is  not  infrequently  found,  also,  that  when  the  impervious  stratum  is- 
penetrated  the  water,  previously  abundant,  is  lost ;  and  then  the  only  plan 
is  to  carry  the  well  downwards  till  at  a  greater  depth  water  is  again  found. 
If  such  a  supply  is  reached  it  may  be  expected,  if  not  too  salme,  to  be 
abundant,  little  liable  to  seasonable  variations  as  to  quantity,  quality,  and 
temperature,  and  organically  pure.  Very  deep  well-waters  are,  nevertheless, 
often  deficient  in  aeration,  or  rather  oxygenation,  as  is  well  seen  in  the  deep 
artesian  well-waters  in  and  around  London,  these  being  sometimes  almost 
destitute  of  dissolved  oxygen. 


SELF-PUEIFICATION   OF   WATEE 

The  so-called  self-purification  of  water  is,  strictly  speaking,  a  misnomer, 
for  in  all  instances  where  self-purification  occurs  the  purification  is  efl'ected 
by  some  other  agency,  except  perhaps  in  one  case — that  of  the  purification 
of  a  water  by  subsidence,  or  the  separation  of  solid  suspended  particles  by 
simply  allowing  the  water  to  come  to  rest.  But  in  even  this  case  the 
separation  of  solid  particles  achieves  a  further  result,  for  dissolved  organic 
matters  are  in  some  way  carried  down  ^^nth  the  deposited  mud.  A  striking 
instance  is  the  purification  of  the  waters  of  the  river  Ehone  during  their 
passage  through  the  Lake  of  Geneva.  The  turbid  and  organically  polluted 
water  enters  the  head  of  the  lake,  having  much  the  appearance  of  road- 
washings,  and  the  clarified  and  purified  water  is  seen  to  issue  from  the  lake 
at  Geneva  as  a  beautifully  pellucid  and  magnificently  blue  stream  (see  p.  250, 
ante). 

Waters  are  also  said  to  be  purified  by  dilution.     It  is  doubtful  whether 


264  HYGIENE 

this  purification  ever  takes  place,  except  in  so  far  as  an  impure  water,  by 
admixture  with  a  purer  water  also  well  aerated,  is  furnished  with  the  oxygen 
necessary  for  the  destruction  of  impurities ;  nor  must  it  be  forgotten  that  when 
a  relatively  small  quantity  of  a  polluted  liquid  is  mixed  with  a  large  quantity 
of  water  of  moderate  purity,  the  added  impurity  may  not  increase  the  im- 
purity of  the  latter  to  such  an  extent  as  to  render  its  assured  detection 
possible  to  the  chemist. 

Dr.  Franliland  and  the  Eivers'  Pollution  Commissioners,  in  their 
celebrated  '  Sixth  Eeport,'  have  thrown  doubts  on  the  self-purifying  power  of 
streams  through  the  agency  of  free  atmospheric  and  dissolved  oxygen  ;  but 
this  position  has  been  successfully  contested  by  Odhng,  Letheby,  Tidy,  and 
others  ;  and  Dr.  Frankland  himself  has  apparently  seen  his  way  to  modify 
his  previous  views  as  to  the  oxidising  power  of  dissolved  oxygen. 

It  is  probable  that  the  salts  of  iron  always  present  in  natural  waters  in 
very  minute  quantity  act  in  some  measure  as  carriers  of  oxygen.  Putrescent 
seAvage  reduces  these  salts  to  the  lower  stage  of  oxidation  of  ferrous  salts — 
e.g.  ferrous  sulphide  ;  and  these,  under  the  influence  of  dissolved  oxygen, 
become  converted  into  ferric  or  more  highly  oxygenated  salts,  which  again 
give  up  their  oxygen  to  organic  matter,  and  are  agam  reduced  to  the  state 
of  ferrous  salts.  However  this  may  be,  the  writer  is  convinced  that  free 
oxygen  is  capable  of  effecting  the  rapid  purification  of  streams,  notwith- 
standing the  adverse  laboratory  experiments  of  Dr.  Frankland.  Some 
think  that  iodine  compounds,  also  rarely  entirely  absent  from  terrestrial 
waters,  act  as  carriers  of  oxygen,  by  their  alternate  oxidation  into  iodates 
and  reduction  to  the  state  of  iodides. 

Ordinary  free  oxygen,  and,  still  less,  atmospheric  air,  oxidise  putrescible 
organic  matters  when  in  dilute  solution  only  slowly  in  laboratory  experi- 
ments. Under  natural  conditions,  where  water  is  exposed  to  an  enormous 
and  practically  unlimited  volume  of  atmospheric  air,  the  result  is  apparently 
different ;  and  it  is  probable  that  atmospheric  ozone  and  peroxide  of  hydrogen 
may  have  much  to  do  with  the  effective  oxidation  of  the  nitrogenous  organic 
substance  present  in  the  polluted  waters  of  rivers.  These  oxidising  agents 
can  have,  however,  little  or  nothing  to  do  with  the  oxidation  of  organic 
matters  in  the  soil,  and  in  the  water  percolating  into  the  subsoil.  Here  a 
different  agency  comes  into  play. 

The  changes  which  nitrogenous  organic  matters  undergo  during  their 
downward  passage  through  the  soil  are,  notwithstanding  the  extended 
investigations  bestowed  upon  them  by  Lawes,  Gilbert,  Warrington,  and 
others,  only  imperfectly  understood.  Under  the  ordinary  conditions  of 
cultivation,  nitrogenous  manures — animal  excreta  in  fact — I'apidly  disappear 
as  such,  their  nitrogen  being  converted,  first  into  ammonia,  and  then  into 
nitrates.  Nitrification  depends  upon  the  presence  of  an  organism,  and  takes 
place  chiefly  in  the  superficial  layers  of  the  soil,  and  does  not  extend,  as  a 
rule,  much  below  18  inches  below  the  surface.  In  a  cultivated  soil  most 
of  the  nitrates  are  absorbed  and  utilised  by  growing  crops,  so  that  but  little 
nitrate  flows  away  in  solution  in  the  subsoil  water.  It  is  not  known  that 
the  water  drawn  from  the  subsoil  beneath  such  manured  soils  is  injuriously 
contaminated,  though  it  is  likely  that  Avhere  the  soil  is  excessively  manured 
the  water  may  be  unwholesome.  It  might,  therefore,  be  anticipated,  d  i^riori, 
that  water  taken  from  greater  depths,  such  as  that  from  shallow  wells,  would 
be  still  less  likely  to  contain  injurious  impurities.  But  abundant  experience 
teaches  us  that  the  water  of  shallow  wells  is  peculiarly  liable  to  contain 
disease-producing  impurities,  except  in  those  cases  where  the  water  supply 
is  protected  by  an  impervious  layer  of  soil,  such  as  clay.     Again,  wells  sunk 


WATEB  2G5 

to  no  great  depth  in  a  gravelly  soil  frequently  yield  an  organically  polluted 
water.  These  differences  may  be  reconciled  on  the  supposition  that  a  well 
draws  polluting  liquids  rapidly  through  the  superficial  and  nitrifying  layer 
of  surface  soil,  so  that  the  organic  matters  pass  through  large  pores  and 
fissures  in  the  soil,  and  thus  escape  the  agency  of  those  organisms  which 
would  otherwise  convert  the  nitrogenous  matter  into  harmless  nitrates.  This 
supposition  receives  confirmation  from  the  well-established  fact  that  the  water 
of  shallow  wells  abounding  in  nitrates,  though  usually  not  decidedly  harmful 
to  drink,  occasionally  gives  rise  to  outbreaks  of  disease,  and  that  these  out- 
breaks are  usually  accompanied  by  a  diminution  of  the  nitrates  habitually 
present  in  the  water,  and  a  corresponding  rise  in  the  organic  nitrogen  and 
albuminoid  ammonia. 

The  enormous  extent  of  purification  of  streams  effected  by  aquatic 
animal  and  vegetable  life  has  been  too  little  appreciated.  Where  fresh 
sewage  flows  from  a  sewer  into  a  stream  the  mouth  of  the  sewer  becomes 
the  feeding-place  of  numerous  small  coarse-feeding  fishes,  which  greedily 
devour  and  convert  into  food  for  larger  fishes  the  scraps  of  muscular  fibre 
and  other  d&hris  which  would  otherwise  decompose  and  pollute  the  stream. 
Minute  particles  of  solid  organic  matter  may,  and  probably  do,  serve  as  the 
food  of  minuter  forms  of  aquatic  animal  life,  and  thus  indirectly  serve  as  food 
for  fish.  The  mud  banks  of  the  Thames  estuary  are  the  habitat  of  the  finest 
flat-fish,  eels,  and  molluscs  which  serve  the  London  market.  But  putrid 
sewage-polluted  streams  are  shunned  by  aquatic  animals,  and  it  is  known 
that  stinking  streams  do  not  readily  undergo  self-purification — as  witness 
the  Thames  ;  though  here  the  saltness  of  the  water  below  London  Bridge 
may  cause  the  water  to  have  a  preservative  effect  on  the  molecules  of  un- 
decomposed  and  decomposing  sewage.  To  what  extent  subsidence,  oxida- 
tion, and  the  presence  of  animal  life  are  respectively  potent  in  bringing 
about  the  purification  of  our  rivers  is  at  present  quite  unknown. 

Nor  must  the  beneficent  effects  of  growing  green  plants  be  ignored. 
Such  plants,  even  those  of  a  low  type,  are  capable  under  the  influence  of 
sunlight  of  effecting  vast  changes  in  the  character  of  a  water.  The  cleaning 
out  of  tanks  and  ponds,  so  as  to  free  them  from  weeds,  has  been  known  to 
render  the  water  of  such  reservoirs  more  impure,  by  depriving  them  of  a 
most  active  agent  of  purification.  The  oxygen  given  off  by  growing  green 
chlorophylliferous  plants  is  probably  like  other  forms  of  nascent  or  atomic 
•oxygen,  peculiarly  active  as  an  oxidiser  ;  and  this  furnishing  of  nascent  oxygen 
maybe  one  of  the  most  valuable  agents  for  effecting  the  oxidation  of  dissolved 
and  minutely  divided  solid  forms  of  organic  matter. 

Lastly,  vegetable  matter  deposited  in  the  bed  of  a  stream  undergoes  a 
fermentative  change,  and  one  of  the  products  of  this  change  is  marsh-gas,  so 
abundantly  liberated  on  stirring  the  bed  of  any  muddy  ditch.  This,  then,  is 
another  mode  by  which  organic  matter  may  be  converted  into  harmless  in- 
organic forms  of  matter. 

Nitrification — effected  by  an  organism — is  not  a  very  active  process  in 
running  water,  and  it  is  a  mode  of  changing  organic  into  inorganic  matter, 
more  effectively  going  on  in  soils  than  in  rivers  and  other  water-courses. 

The  probably  enormous  changes  brought  about  by  schizomycetes  (bacilli, 
bacteria,  &c.)  must  also  not  be  forgotten. 

Altogether,  then,  the  natural  purifying  agencies  ordinarily  going  on  in 
streams  are  in  the  aggregate  enormous,  and  generally  effective. 

Dr.  Tidy,  who  is  one  of  the  strongest  defendants  of  the  potability  of  river 
water,  even  after  the  influx  of  sewage,  after  a  review  of  all  the  facts,  thus 
summarises  his  conclusions  : 


2Gr.  HYGIENE 

1.  That  -svLen  sewage  is  discharged  into  running  water,  provided  the 
piimary  dikition  of  the  sewage  with  pure  water  be  sufficient,  after  the  run 
of  a  few  miles,  the  precise  distance  of  travel  being  dependent  on  several 
conditions,  the  removal  of  the  whole  of  the  organic  impurity  will  be  effected. 

2.  That,  whatever  be  the  actual  cause  of  certain  diseases,  i.e.  whether 
germs  or  chemical  poisons,  the  materies  morhi  which  finds  its  way  into  the 
river  at  the  sewage  outfall  is  destroyed,  together  with  the  organic  impurity, 
after  a  certain  flow. 

These  conclusions  were  formulated  before  the  bacteriology  of  specific 
diseases  was  developed  ;  but  observation  appears  to  show  that  a  How  of  20 
miles  in  a  river  is  not  sufficient  to  destroy  the  germs  of  typhoid  fever. 
Dr.  Barry,  m  a  recent  report  to  the  Local  Government  lioard,  expresses  his 
opinion  that  a  flow  of  40  miles  at  least  is  necessary  after  an  irruption  of 
sewage  in  order  to  render  the  river-water  a  desirable  supply  for  drinking 
purposes.  He  bases  his  opinion  on  an  outbreak  of  typhoid  fever  following 
an  irruption  of  lilth  into  the  river  Tees. 


EFFECTS  OF  IMPURE  ^yATER 

No  one  in  the  present  day  doubts  that  epidemics  may  spread  by  means 
of  diinking-water,  and  the  surmises  of  physiologists  that  this  is  brought 
about  by  specific  living  germs  or  spores  have  within  the  last  few  years  been 
confirmed  by  the  actual  discovery  of  the  bacilli  or  bacteria  which  are 
the  active  factors  in  propagating  certain  forms  of  disease.  But  whether 
the  germs  of  disease  present  in  drinking-water  are  the  actual  direct  agents 
in  communicating  disease,  or  whether  the  chemical  products  of  the  active 
changes  involved  in  the  life-history  of  these  germs  are  the  intermediate  fac- 
tors, is  not  yet  altogether  determined.  There  is  evidence,  however,  tending 
to  shoAV  that  it  is  in  some  cases  the  actual  germs  or  living  organisms  in  water 
which  propagate  disease ;  for  waters  specifically  infected  with  dejecta,  con- 
taining minute  traces  only  of  organic  matter,  are  capable  of  spreading  a 
disease.  It  is  highly  probalble  that  when  a  water  receives  typhoid  or  cholera 
germs,  these  do  not  multiply  in  the  water,  but  gradually  perish,  having  no 
appropriate  nidus  in  which  they  may  develop  ;  but  that  if  the  water  still 
containing  any  such  living  germs  be  drunk,  a  sufficiency  of  these  may  be 
taken  into  the  hmnan  body  to  set  up  active  disease,  provided  the  body  be  in 
a  fit  state  for  the  germs  to  midergo  development.  The  well-known  fact  that 
when  typhoid  and  cholera  dejecta  are  very  largely  diluted  with  water  they 
become  incapable  of  spreading  these  diseases  points  apparently  to  the  oppo- 
site conclusion  ;  but  it  may  be  that  the  usual  non-spreading  of  cholera  and 
typhoid  epidemics  where  the  dejecta  have  been  enormously  diluted  is  to  be 
explained  by  the  few  germs  received  by  any  one  individual  on  drinking  the 
excrement-polluted  water.  The  experiments  of  Chauveau  ('  Comp.  Eendus,' 
18G8,  pp.  289,  317,  and  359  ;  '  12th  Eep.  of  Med.  Off.  of  Privy  Council,  1869  ') 
have  shown  clearly  that  it  is  the  solid  particulate  matter  of  vaccine  and 
small-pox  virus,  &c.,  and  not  the  soluble  components  thereof,  which  is  con- 
cerned in  the  propagation  of  these  diseases  by  inoculation.  Brieger's  more 
recent  researches,  and  those  of  Dr.  Sidney  Martin  ('  19tli  Eep.  Med.  Officer 
Loc.  Gov.  Bd.'  p.  235)  show,  on  the  other  hand,  that  bacteria  may  produce 
specifically  toxic  chemical  compounds. 


WATER  ^m 


Cholera 


That  cholera  is  a  disease  which,  in  this  country  at  all  events,  is  or  has 
been  largely  propagated  by  means  of  excrement-polluted  water-supplies,  is 
abundantly  evident.  The  experience  of  London  as  to  cholera  is  most  instruc- 
tive, and  as  strikingly  put  in  the  '  0th  Eeport  of  the  Rivers  Pollution  Commis- 
sioners.' Epidemics  of  cholera  have  prevailed  in  London  in  the  years  1832, 
1849,  1854,  and  1866.  In  1832  a  considerable  part  of  London  was  supplied 
with  water  from  the  rivers  Thames  and  Lea,  and  the  remainder  from  shallow 
wells.  But  at  that  time  the  river  water  could  not  have  been  nearly  so 
polluted  as  subsequently,  in  consequence  of  the  absence  of  sewers  and  the 
comparative  smallness  of  the  population.  The  death-rate  from  cholera  in  1882 
was  3"14  per  1000  of  the  population.  In  1849  the  water  was  drawn  from 
similar  sources,  except  that  more  water  relatively  was  drawn  from  the  river 
than  from  wells.  But  meantime  sewers  had  been  constructed  and  water- 
closets  were  in  general  use.  Hence  the  river  supply  of  water  must  neces- 
sarily have  been  much  more  impure  than  on  the  occasion  of  the  cholera 
visitation  of  1832,  and  the  mortality  from  this  disease  rose  to  6"18  per  1000. 
In  the  epidemic  of  1854  the  mortality  was  4*29  per  1000.  In  1866  the  main 
drainage  scheme  of  the  metropolis  had  been  carried  out,  and  the  sewage  was 
discharged  into  the  Thames  miles  below  London  Bridge.  In  this  epidemic 
the  mortality  fell  to  1"8  per  1000.  In  the  cholera  epidemic  of  1849  in 
London,  it  was  observed  that  the  population  supplied  with  water  from  the 
Thames  suffered  more  and  more  from  cholera  according  as  the  water  was 
abstracted  from  the  river  at  successively  lower  points.  Thus  of  those  sup- 
plied with  water  taken  from  the  river  at  Kew,  0*8  per  1000  died  of  cholera  ; 
those  supplied  with  water  drawn  at  Hammersmith,  lower  down  the  river, 
perished  to  the  extent  of  1*7  per  1000  ;  in  the  west  of  London,  the  water 
being  taken  at  Chelsea,  4*7  per  1000  died  ;  whilst  of  those  supplied  with 
water  abstracted  between  Battersea  and  Waterloo  Bridge,  i.e.  in  the  metro- 
polis, no  less  than  16"3  per  1000  died  of  cholera  alone.  When  cholera  next 
visited  London,  in  1854,  the  Southwark  Water  Company  still  continued  to 
draw  its  supply  from  the  river  at  Battersea,  close  to  one  of  the  sewers ;  and 
the  river  was  presumptively  filthier  than  in  1849.  In  Bermondsey,  which 
was  supplied  with  water  by  the  above  company,  the  deaths  from  cholera  in 
1854  were  greater  by  13  per  cent,  than  in  1849 — a  difference  more  than 
corresponding  to  the  increased  population.  But  in  the  interval  of  five  years 
the  Lambeth  Water  Company  had  removed  their  intake  to  a  point  above  the 
tidal  lock  at  Teddington  ;  and  it  was  found  on  comparing  the  houses  in  the 
same  district  supplied  by  the  two  companies — the  pipes  of  the  two  companies 
often  interlacing  in  the  same  street — that  in  the  houses  supplied  from  the 
river  within  the  metropolitan  area  the  deaths  from  cholera  were  57'1  per 
1000  houses,  whilst  in  those  supplied  from  the  Thames  above  London  and 
the  tidal  influence  the  deaths  w^ere  only  11-3  per  1000  houses.  Well  might 
Sir  John  Simon  term  this  a  '  gigantic  crucial  experiment  performed  on  half 
a  million  of  people  '  (Eoyal  Commission  on  Water  Supply,  1869 ;  '  Min.  of 
Evid.'  p.  143). 

Perhaps  a  still  more  striking  experiment  was  made  in  the  east  of  London, 
in  the  cholera  outbreak  of  1866,  by  the  East  London  Water  Company,  which, 
in  the  language  of  the  Rivers  Pollution  Commissioners  ('  Sixth  Rep.'  p.  145) 
distributed  '  unfiltered  water  excessively  polluted  with  sewage,'  and  which,  in 
the  opinion  of  Mr.  Netten  Radcliffe,  was  specifically  contaminated  with  the 
excrement  of  the  first  two  patients  who  died  in  that  year  of  cholera  in  the 


2G8  HYGIENE 

east  districts  of  London.  Now  the  district  of  the  East  London  Company, 
supphed  with  water  from  this  Old  Ford  reservoir,  was  the  portion  of  their 
district  which  was  the  sole  area  of  intense  cholera  in  London  in  1866.  Again 
to  quote  Sir  John  Simon's  words,  '  The  area  of  intense  cholera  in  1866  was 
almost  exactly  the  area  of  this  particular  water-supply,  nearly,  if  not  abso- 
lutely, filling  it  and  scarcely,  if  at  all,  reaching  beyond  it '  {ibid.  p.  144). 

It  is  not  contended  that  water  is  the  sole  agent  concerned  in  the  distribu- 
tion of  cholera  contagion,  but  it  is  certainly  one  of  the  chief  media  for  extend- 
ing the  disease. 

Perhaps  the  most  instructive  and  striking  instance  of  the  spread  of  cholera 
through  the  medium  of  polluted  water  is  recorded  as  having  occurred  in  1854 
around  Golden  Square,  Soho,  by  means  of  the  Broad  Street  pump.  This 
district,  in  which  a  formidable  outbreak  of  cholera  occurred,  had  a  population 
in  1851  of  42,272,  and  was  not  a  low-class  district.  During  August  1854 
cholera  was  prevalent  in  the  locality,  but  not  to  a  serious  extent ;  but  on 
September  1  the  disease  broke  out  with  fearful  \dolence,  and  continued  till 
the  morning  of  the  5th,  when  it  began  to  abate.  One  of  the  chief  features  of 
this  memorable  outbreak  was  its  suddenness,  and  the  large  number  of  indi- 
viduals simultaneously  attacked  in  different  parts  of  the  district.  The  total 
number  of  deaths  fi'om  cholera  in  September  recorded  in  this  limited  area 
was  609,  or  14*2  per  1000  of  the  population.  This  district  contained  a  public 
pump — the  Broad  Street  pump  ;  and  this  pump  was  the  centre  of  the  infected 
district,  for,  starting  thence,  a  person  walking  at  a  moderate  pace  in  any 
direction  would  have  gone  beyond  the  limits  of  the  infected  area  within  three 
minutes.  A  special  examination  showed  that  the  water  of  the  well  was  con- 
taminated by  filtration  from  a  cesspool  during  the  time  of  the  cholera  out- 
break. Though  the  water  of  the  well  was  grossly  impure,  it  was  in  great 
repute  through  the  neighbourhood  for  drinking  purposes,  and  was  much  liked, 
being  cool,  sparkling  with  carbon  dioxide  gas,  and  keeping  well,  in  consequence 
of  the  large  quantity  of  saline  matter  it  contained.  But  on  exposure  to  the 
air  for  a  few  hours  it  lost  its  freshness,  and  became  offensive  in  a  few  days. 
Dr.  Snow  was  able  to  show  that  not  only  was  the  outbreak,  properly  so  called, 
principally  confined  to  near  about  the  pump,  but  that  61  out  of  73  persons 
who  died  during  the  first  two  days  had  been  accustomed  to  drink  the  pump- 
water  ;  that  in  the  workhouse,  where  the  well-water  was  not  used,  the  deaths 
from  cholera  were  only  one-tenth  of  the  ratio  prevalent  in  the  neighbourhood  ; 
that  no  less  than  9  per  cent,  of  the  people  in  a  factory  Avhere  the  water  was 
■drunk  daily  died  ;  and  that  70  men  employed  in  a  brewery  in  Broad  Street, 
and  who  never  drank  the  water,  all  escaped  cholera.  Livestigation  of  numerous 
individual  cases  entirely  confirmed  the  conclusion  that  the  Broad  Street  pump 
water  was  mainly  instrumental  in  propagating  the  outbreak  of  disease. 

In  further  confirmation  of  the  view  that  water  is  a  fertile  agent  in  spread- 
ing the  disease,  the  instance  may  be  adduced  of  the  outbreak  of  cholera  on 
board  a  steam-vessel  in  1866  recorded  by  Parkes  ('  9th  Eep.  of  the  Med.  Officers 
of  thePri^'y  Covmcil  for  1866,'  p.  244)  ;  the  case  of  Utrecht  ('  Med.  Times  and 
Gaz.'  1869,  I.  p.  626)  ;  and  the  striking  coincidences  in  Scotland  between  the 
abatement  of  cholera  and  the  introduction  of  a  fresh  and  pure  water-supply. 
('  Trans,  of  the  Pioyal  Scottish  Soc.  of  Art,'  vol.  vii.  1867,  p.  341,  quoted  by 
Parkes). 

It  must  be  admitted  that  this  statistical  evidence  is  inconclusive,  and  that 
it  has  been  severely  criticised  by  eminent  authorities.  It  is,  however,  in 
accord  with  other  data,  and  cannot  be  ignored.  When  supplemented  by  the 
data  derived  from  the  investigation  of  individual  circumstances  of  outbreaks 
of  cholera,  its  significance  becomes  manifest. 


WATER  269 

In  Germany  the  connection  between  cholera  and  contaminated  water- 
supply  has  not  obtained  general  acceptance  ;  and  the  great  authority  of 
Pettenkofer  could  find  no  evidence  from  the  experience  of  Munich  in  favour 
of  the  theory  ('  Zeitschr.  f.  Biol.'  Bd.  I,  p.  353).  Giinther,  too,  asserted  that  in 
1865  no  connection  could  be  traced  in  Saxony  between  impure  drinking-water 
and  cholera  ('  Cholera  in  Sachsen  im  Jahre  18G5,'  p.  125,  quoted  by  Parkes). 
But  the  subsequent  experiences  of  Eichter  ('  Arch.  d.  Heilk.'  1867,  p.  472),  and 
Dinger  {ibid.  1867,  p.  84),  and  others,  have  tended  to  establish  such  a  connec- 
tion. In  India  many  observers  have  denied  the  causal  connection  of  water 
and  cholera ;  and  the  late  Dr.  J.  M.  Cunningham,  once  a  firm  believer  in  the 
connection,  subsequently  renounced  the  theory  of  the  water-carriage  of  cholera. 
It  cannot,  therefore,  be  asserted  that  the  theory  is  fully  established  to  the 
satisfaction  of  all  competent  observers.  It  may  be  that  the  conditions  of  the 
dissemination  of  cholera  may  be  different  in  India  from  those  which  obtain 
in  the  cooler  climate  of  England  ;  but  this  is  hardly  supposable  to  be  the  case 
when  England  and  Germany  are  compared. 

Typhoid  Fever 

This  endemic  fever  kills  some  five  or  six  thousand  people  annually  in 
England  and  Wales  out  of  a  population  of  twenty-six  millions,  or  0-2  per  1000. 
The  poison  of  typhoid  indubitably  exists  in  the  bowel  evacuations  of  those 
suffering  from  the  disease,  and  hence  is  very  frequently  introduced  into 
drinking-water,  which,  as  is  now  well  known,  thus  becomes  a  chief,  but  by 
no  means  the  sole,  agent  in  the  distribution  of  typhoid.  Moreover,  it  is  now 
pretty  generally  accepted  that  the  germ  of  typhoid  is  a  bacillus  {Bacillus 
typhosus,  E.  Corth),  or  rod-shaped  schizomycete.  It  is  stated  that  inoculation 
experiments  made  with  this  bacillus  have  been  successful  (Eenkel  u.  Simonds ' 
'  Die  ^tiol.  bed.  des  Typhus  bacillus  ').  But  long  before  this  discovery  was 
announced  the  connection  between  typhoid  and  water-supply  had  been  one 
of  the  best  established  conclusions  of  scientific  medicine ;  and  the  discovery 
of  the  active  bacillus  of  typhoid  seemed  from  a  public -health  point  of  view 
merely  to  support  the  definite  conclusions  arrived  at  by  statistical  and  indi- 
vidual inquiries  into  the  causation  of  the  disease. 

The  proofs  of  this  assertion  lie  elsewhere.  In  1854  typhoid  fever,  then  the 
scourge  of  Millbank  Prison,  which  drew  its  water  from  the  polluted  Thames, 
was  practically  extinguished  by  the  cessation  of  the  old  supply  and  the 
adoption  of  a  water-supply  from  the  deep  artesian  well  in  Trafalgar  Square 
('Lancet,'  1872, 1,  p.  787). 

In  1867  a  severe  outbreak  of  typhoid  fever  at  TerHng,  in  Essex,  was  investi- 
gated by  Dr.  Thorne  by  order  of  the  Privy  Council.  One-third  of  the  inhabi- 
tants of  Terling  were  attacked  by  the  disease,  and  the  death-rate  was  45  per 
1000  of  the  population.  Three  weeks  after  the  appearance  of  the  first  (and 
perhaps  imported)  case,  the  disease  broke  out  with  alarming  virulence,  and  no 
class  of  persons  was  exempt.  The  epidemic  was  preceded  by  a  drought,  and  was 
coincident  with  a  rise  of  water  in  the  village  wells  consequent  on  heavy 
rainfall ;  and  these  wells  were  much  exposed  to  pollution  by  excremental 
filth.  Indeed,  in  summer,  to  use  the  expression  of  a  resident,  they  were 
'  nothing  better  than  stinking  pools.'  There  was,  moreover,  ample  proof  of 
the  connection  between  the  rise  of  water  in  the  wells  and  the  attack  of  th& 
disease. 

This  Terling  outbreak  was  a  signal  instance  of  the  immunity  from  typhoid 
often  seen  in  a  population  habitually  drinking  a  filthy  water,  so  long  as  this 
contains  no   specific  contaminating    material.      The   introduction   of  the 


270  HYGIENE 

specifically  polluted  filth  from  typhoid  stools  at  once  determined,  however, 
a  virulent  epidemic  of  typhoid  fever  ('  10th  Report  of  the  Med.  Off.  of  Privy 
Council,'  1867,  p.  41). 

Other  instances  may  be  adduced  in  confirmation  of  the  teachings  of  the 
Terling  outbreak. 

The  most  striking  instance  illustrative  of  the  occasional  persistency  of 
the  typhoid,  and  other  similar  poisons,  when  they  are  diffused  in  water,  and 
then  exposed  to  oxidising  influences,  occurred  at  the  village  of  Lausen,  near 
Bale,  in  Switzerland,  and  was  investigated  by  Dr.  A.  Hiigler,  of  Bale  ('  Deut. 
Vierteljahrsschrift  f.  offentl.  Gesundhcitspficge,'  Bd.  VI.  S.  154 ;  and  '  6th 
Report  of  the  Rivers  Pollution  Commissioners,'  p.  463).  In  this  previously 
healthy  village,  which  had  never  been  known  to  be  visited  by  an  epidemic  of 
typhoid  fever,  and  in  which  not  even  a  single  sporadic  case  of  the  disease  had 
been  observed  for  many  years,  an  epidemic  broke  out  in  August  1872,  which 
attacked  almost  simultaneously  a  large  proportion  of  the  inhabitants.  Some 
miles  soutli  of  Lausen,  and  separated  from  it  by  the  mountain  ridge  of  the 
Stockhalden,  hes  the  small  parallel  valley  of  the  Flirlerthal.  In  this  valley 
lived  a  farmer,  in  a  solitary  farmhouse,  Avho  was  attacked  on  June  10  by 
typhoid  fever,  just  after  his  return  from  a  long  journey.  A  girl  was  attacked 
in  the  same  house  on  July  10 ;  and  in  August  the  farmer's  wife  and  son  sickened 
of  the  same  disease.  There  was  no  communication,  so  far  as  could  be  ascer- 
tained, between  the  farmhouse  and  the  village  of  Lausen.  On  August  7,  ten 
of  the  villagers  in  Lausen  were  attacked  by  typhoid,  and  within  the  next  nine 
days  the  number  of  cases  had  risen  to  57,  out  of  a  population  of  780  living 
in  90  houses.  Within  the  first  four  weeks  of  the  epidemic  the  number  of 
cases  rose  to  100,  and  at  the  close  of  the  epidemic,  at  the  end  of  the  following 
October,  130  persons — or  17  per  cent,  of  the  inhabitants — were  attacked ; 
besides  14  children  infected  in  the  village  during  their  holidays,  and  who 
sickened  with  typhoid  after  their  return  to  schools  in  other  places. 

Except  in  six  houses,  which  were  supplied  with  water  from  their  own 
wells,  the  cases  were  pretty  evenly  distributed  throughout  the  entire  village, 
and  the  above  six  houses  were  exempt  from  typhoid.  This  remarkable  fact 
threw  suspicion  upon  the  pubHc  water-supply,  which  came  from  a  spring  at 
the  foot  of  the  Stockhalden  ridge,  which  is  probably  an  old  moraine  of  the 
glacial  epoch,  and  such  a  source  might  reasonably  be  regarded  as  above 
suspicion  of  pollution.  Observations  upon  a  brook  in  the  Flirlerthal  Valley 
and  of  the  spring  at  Lausen  showed,  however,  that  there  was  a  direct  com- 
munication between  the  two.  Among  the  observations  it  was  noted  that  when- 
ever the  meadows — below  a  hole  spontaneously  formed  ten  years  before  by 
the  giving  way  of  the  soil  a  little  below  the  farmhouse — were  irrigated  with 
water  from  the  Fiirler  brook,  the  volume  of  the  Lausen  spring  became  greatly 
increased  within  a  few  hours.  This  irrigation  had  been  carried  on  during 
the  summer,  from  the  middle  to  the  end  of  July,  the  brook  being  polluted  by 
the  typhoid  dejecta  of  the  farmhouse  patients.  It  was  in  direct  communi- 
cation with  the  closets  and  dungheaps  of  the  infected  house  ;  all  the  chamber 
slops  were  emptied  into  it,  and  the  dirty  linen  of  the  patients  was  washed 
therein.  It  was  observed,  also,  that  the  water  supplied  to  Lausen  was  at  first 
turbid,  acquired  an  unpleasant  taste,  and  increased  in  volume.  Three  weeks 
or  so  after  the  commencement  of  the  irrigation  the  epidemic  began  in  Lausen. 
But  Dr.  Hagler  did  not  rest  satisfied  with  this  evidence,  and  made  the  follow- 
ing experimental  demonstration  of  the  correctness  of  the  assumption  that 
the  epidemic  was  due  to  the  pollution  of  the  Lausen  water-supply  by  the 
dejecta  of  the  typhoid  patients  in  Flirlerthal.  The  above-mentioned  hole  in 
the  Fiirler  valley  was  opened,  and  the  brook  led  into  it ;  three  hours  later  the 


WATEB  271 

fountains  of  Lausen  gave  out  double  their  previous  delivery  of  water.  A 
solution  of  18  cwt.  of  common  salt  in  water  was  now  poured  into  the  hole, 
and  soon  the  Lausen  water  was  found  to  react  more  strongly  for  chlorides 
than  before  ;  the  chlorine  reaction  went  on  increasing,  and  the  proportion  of 
ealine  matter  in  the  fountains  had  increased  threefold.  All  doubt  as  to  the 
passage  of  water  from  the  fever-stricken  Fiirlerthal  to  Lausen  being  thus 
removed,  the  question  as  to  whether  the  water  found  its  way  through  natural 
fissures,  or  percolated  through  porous  strata,  was  attempted  to  be  solved  by 
carefully  and  uniformly  diffusing  2^  tons  of  flour  through  water,  which  was 
then  thrown  into  the  hole.  But  neither  an  increase  in  the  amount  of  solid 
constituents  nor  any  turbidity  of  the  Lausen  water  was  observed  to  result 
from  the  addition.  It  appears  to  the  writer,  however,  that  this  experiment, 
in  the  face  of  the  previously  observed  turbidity  of  the  fountains  whilst  irriga- 
tion was  going  on  in  the  Fiirler  valley,  is  not  conclusive  against  the  possi- 
bility of  the  water  finding  its  way  from  Fiirlerthal  to  Lausen  by  natural  con- 
duits. Two  things  this  interesting  epidemic  does,  nevertheless,  prove  beyond 
doubt :  first,  that  animal  excreta  do  not,  when  taken  in  drinking-water,  pro- 
duce typhoid  ;  and  next,  that  typhoid  excreta  may,  when  introduced  into  a 
water-supply,  induce  typhoid  in  a  distant  community,  when  the  water  in  its 
passage  is  not  freely  exposed  to  the  atmosphere. 

It  is  perhaps  unnecessary  to  introduce  further  instances  in  illustration 
of  the  two  important  facts  that  typhoid  fever  may  be  spread  by  the  use  of 
contaminated  drinking-water,  and  that  in  places  where  typhoid  fever  has 
been  habitually  prevalent,  the  disease  may  be  practically  eliminated  by  the 
introduction  of  a  pure  water-supply. 

DiAEEHCEA 

That  diarrhoea  may  result  from  the  drinking  of  impure  water,  no  sani- 
tarian will  doubt;  The  diarrhoea  thus  produced  may  be  of  a  varied  character, 
and  be  due  to  a  variety  of  causes. 

1.  Sulphuretted  hydrogen  in  a  water  may  cause  diarrhoea.  In  the 
Mexican  war  of  1861-2,  such  a  form  of  diarrhoea  was  produced  by  the  drink- 
ing of  water  abounding  in  alkaline  sulphides  (Poncet).  Medicinal  sulphu- 
retted waters  (e.g.  those  of  Harrogate)  are  well-known  purgatives.  Other 
foetid  gases  in  water  (e.g.  sewer  gases)  may  produce  a  similar  result. 

2.  Suspended  matters,  animal  (ftecal),  vegetable,  and  mineral,  may  cause 
diarrhoea.  Some  of  these — e.g.  clay,  mica,  &c. — may  act  as  simple  mechanical 
irritants,  whilst  suspended  animal  and  vegetable  substances  may  act  speci- 
fically upon  the  intestinal  tract. 

3.  Dissolved  Nitrogenous  Organic  Matter. — An  excess  of  this,  if  of 
animal  origin,  may  provoke  diarrhoea.  That  derived  from  cemeteries  is  gene- 
rally supposed  to  do  this  in  a  marked  manner.  The  writer's  experience  is, 
however,  that  such  dissolved  matters  are  not  generally  more  prone  to  do  this 
than  other  animal  substances. 

Dissolved  vegetable  matters  appear  to  have  no  marked  effect,  except  in 
the  case  of  peaty  and  marshy  waters.  Mr.  Wanklyn,  nevertheless,  has 
drawn  attention  to  the  circumstances  of  Leek  Workhouse,  where,  for  several 
years,  there  was  a  general  tendency  to  diarrhoea,  which  was  not  accounted 
for  until  the  water  was  examined  and  shown  to  be  loaded  with  vegetable 
matter  ;  and  he  also  instances  the  case  wherein  a  well  on  Biddulph  Moor, 
in  the  same  district  of  Staffordshire,  yielded  on  analysis  only  O-o  grain  of 
chlorine  per  gallon — showing  absence  of  any  appreciable  sewage  contami- 
nation— but  yielded  a  rather  considerable  quantity  of  albuminoid  ammonia 


272  HYGIENE 

(0-14  part  per  million,  or  0-0098  grain  per  gallon).  Persons  -who  were  in  the 
habit  of  drinking  this  water  suffered  fii-om  diarrhoea  (•  Water  Analysis,' 
p.  49). 

4.  Dissolved  Mineral  Matters. — These,  even  when  of  the  most  simple 
and  innocuous  character,  when  in  excess  may  have  a  purgative  effect,  as  is 
seen  in  the  case  of  many  purgative  medicinal  waters.  Sulphate  of  magnesium 
and  sulphate  of  calcium  are  most  notable  as  producing  this  effect.  The 
illness  produced  may  be  of  a  specific  character,  as  in  the  case  of  contamination 
by  lead  (q.v.,  p.  250)  or  by  chromium. 

Dysentery 

Impure  water  is  credited  with  being  a  fertile  source  of  dysentery.  The 
connection  of  this  disease  with  the  use  of  impure  water  has  been  recognised 
for  nearly  a  century.  Cornuel  records  an  outbreak  of  the  disease  at  Guada- 
loupe  in  1847,  caused  by  the  use  of  impure  water  ;  and  the  Walcheren  fever, 
in  1809,  was  associated  by  Da\ds  ('  On  the  Walcheren  Fever'),  ^dth  the 
drinking  of  impure  brackish  water.  Chevers  in  India,  Champouillon  in 
France,  and  McGrigor  in  the  Spanish  Peninsula,  have  each  observed  outbreaks 
of  dysentery  from  the  same  now  well-recognised  cause.  Generally,  it  may  be 
stated  that  those  forms  of  water-pollution— gaseous,  soluble,  and  suspended 
matters — which  produce  diarrhoea  may,  under  other  circumstances,  produce 
dysentery. 

Affections  op  Mucous  Membeanes 

The  effects  of  impurities  in  drinking-water  are  not  limited  to  the  in- 
testinal tract,  and  may  affect  other  portions  of  the  alimentary  and  other 
mucous  membranes.  Gastro-intestinal  catarrh  is,  perhaps,  not  an  in- 
frequent result  of  the  use  of  impure  water. 

Influence  of  Earthy  and  Metallic  Impurities 

These  have  already  been  sufficiently  treated  of  under  various  headings 
(see  Lead,  p.  256,  Chromium,  p.  256,  and  Magnesium  Salts,  supra). 

Yellow  Fever 

It  is  most  uncertain  whether  this  disease  is  propagated  by  means  of 
■water,  the  evidence  as  to  this  being  conflicting. 

Malaria  from  Water 

Simple  peaty  water  is  not  generally  decidedly  unwholesome,  though  it 
not  seldom  produces  temporary  diarrhoea  when  drunk  by  those  unaccustomed 
to  its  use.  Marsh-water  has,  however,  from  early  times  been  considered 
unwholesome  and  a  provocative  of  disease.  Hippocrates  refers  to  the 
popular  notion  in  his  time,  that  those  who  drink  the  water  of  marshes  get 
hard  and  enlarged  spleens.  The  inhabitants  of  marshy  tracts  of  country 
are  pretty  generally  agreed  that  these  waters  may  produce  fevers.  Dr. 
E.  Parkes  states  that  on  inquiring  in  the  malarious  plains  of  Troy  during 
the  year  1854,  he  was  informed  by  the  villagers  that  those  who  drank  marsh- 
waters  had  ague  at  all  seasons,  whilst  those  who  drank  pure  water  only  got 
ague  during  the  late  summer  and  autumn ;  and  he  adds  from  his  Eastern 
experience  that  the  same  belief  prevails  in  South  India.  Mr.  Bettington,  of 
the  Madras  Civil  Service,  stated  that  it  was  notorious  that  marsh-water 


WATEB  273 

produces  fever  and  affections  of  the  spleen  ;  and  he  instanced  a  notoriously 
unhealthy  village  in  which  by  simply  digging  a  well  the  inhabitants  were 
freed  from  these  maladies. 

Indeed,  medical  literature,  and  especially  the  annals  of  the  Indian  and 
British  military  services,  abound  in  striking  instances  apparently  pointing 
the  connection  between  marsh-water  and  aguish  attacks  as  cause  and 
effect. 

Nevertheless  there  are  anomalies  and  apparent  exceptions  to  this  con- 
nection, well  deserving  of  more  rigorous  investigation  than  they  have 
hitherto  received.  Thus  it  is  asserted  that  the  water  of  the  celebrated 
Dismal  Swamp  of  the  North  American  Continent — a  typically  marshy  water 
— is  not  injurious  to  health,  but  is  held  in  high  estimation  for  use  on  board 
ships.  This  instance  is,  however,  inconclusive,  since  it  is  a  notorious  fact 
that  water  charged  with  organic  impurities,  more  especially  of  vegetable 
origin,  when  stored  undergoes  a  kind  of  fermentation  which  materially 
alters  its  character,  and  may  as  the  result  render  a  highly  impure  water 
palatable  and  wholesome. 

The  evidence  as  to  the  unwholesomeness  of  marsh  water  is  to  the  writer's 
mind  conclusive. 

GOITEE 

That  impure  drinking-water  is  the  cause  of  goitre  has  been  a  prevailing 
opinion  among  physicians  since  early  times  ;  and  it  is  even  stated  that  by 
drinking  certain  waters  French  and  Italian  soldiers  can  produce  that 
disease,  and  so  claim  exemption  from  conscription.  The  evidence  in 
favour  of  goitre  being  caused  by  the  use  of  certain  kinds  of  drinking- 
water  is  undoubtedly  very  strong,  and  probably  well  founded ;  but  the 
nature  of  the  substance  which  produces  goitre  is  unknown.  The  absence 
of  iodine,  and  the  presence  of  an  excess  of  magnesium  salts,  also  ex- 
cessive hardness,  have  all  been  credited  as  exciting  causes  ;  and  yet  each 
one  of  these  alleged  causatives  has  been  found  absent  in  the  waters  drunk 
by  those  living  in  goitrous  districts.  Thus  iodine  has  been  found  present, 
and  Dr.  J.  B.  Wilson  found  that  at  Bhagsoo,  Dharmsala,  India,  where  goitre 
prevails,  all  the  waters  of  the  district  are  soft,  non-calcareous,  and 
destitute  of  magnesian  compounds  (Aitkin's  '  Science  and  Practice  of 
Medicine ').  Usually,  however,  goitre  prevails  mostly  in  calcareous  soils, 
and  especially  where  the  water-supply  is  drawn  from  the  magnesian  lime- 
stone formation.  Nevertheless,  goitre  does  not  appear  to  be  a  prevalent 
disease  in  Sunderland  or  in  Bristol,  towns  which  have  water-supphes  which 
are  hard,  calcareous,  and  exceptionally  rich  in  magnesium  salts. 

Evidently,  the  whole  subject  of  the  relation  of  goitre  to  water-supply 
needs  reinvestigation.  A  large  mass  of  information  on  the  subject  is  given 
by  Saint-Lager  ('  Sur  les  Causes  du  Cretinisme  et  du  Goitre  end<Jmique  '). 

Pabasitic  Diseases 

Impure  Water,  containing  the  ova  of  entozoa,  &c.,  is  a  fertile  source  of 
parasitic  disease  in  warm  climates,  and  perhaps  to  a  much  less  extent  in 
the  temperate  climate  of  Great  Britain,  where,  it  must  be  admitted,  water- 
supplies  are  much  less  prone  to  contain  the  ova  of  entozoa,  in  consequence 
of  the  less  filthy  habits  of  our  people  than  in  Poland,  Eussia,  and  other 
temperate  climates. 

The  following  is  a  list  of  the  infecting  organisms  which  have  been  alleged 
to  have  been  found  in  drinking-water : 

VOL.  I.  T 


274  HYGIENE 

1.  Tania  lata  {Bothriocephalus  lakts). 

2.  Distoma  hepatlcum  (fluke). 

3.  Ascaris  lumbricoides  (round  worm). 

4.  Filiaria  Dracunculus  (Guinea-Avorm). 
6.  Filiaria  sanguinis  hominis. 

6.  Oxyuris  vermicularis. 

7.  Dochviius  duodenalis  [Strongylns  duodcnalis ;  Sderostoma  duodcnaU ; 
Anchylostovmnn  duodenale). 

8.  Billharzia  hcematohia. 

9.  Sanguisuga  medicinalis  (the  speckled  leech),  S.  officinalis  (the  green 
leech),  and  other  species  of  leech. 


WATER  ANALYSIS 
The  Collection  of  Samples  of  ^YATER 

The  proper  collection  of  samples  of  water  for  analysis  is  all -important 
as  regards  the  method  of  taking  the  samples,  the  cleanliness  of  the  vessels 
employed,  and  the  quantities  requisite.  The  quantity  of  water  required  for 
an  analysis  will  vary  according  to  the  kind  of  analysis  which  it  is  desired  to 
make.  A  full  analysis  of  all  the  constituents  is  rarely  required.  Usually 
half  a  gallon  suffices  for  the  purposes  of  an  ordinary  analysis  for  sanitary 
purposes. 

A  glass-stoppered  hottle  of  the  kind  known  as  the  *  Winchester  Quart ' 
is  the  best  hottle  to  be  used  for  the  purposes  of  collecting  and  storing  the 
sample.  These  bottles  hold  rather  more  than  half  a  gallon.  A  clean  new 
well-rinsed  cork  may  be  substituted  for  a  stopper,  if  one  be  not  at  hand. 
The  bottle  should  be  well  cleansed,  and  rinsed  with  clean  tap-water.  It  is 
always  undesirable  to  use  an  opaque  vessel,  such  as  a  stoneware  jug,  for  the 
collection  of  samples  of  water,  as  their  cleanliness  and  freedom  from  con- 
taminating material  can  never  be  ensured. 

Before  filling  the  clean  bottle  with  the  sample,  it  should  be  rinsed  three  or 
four  times  with  the  water  to  be  collected  before  filling  it  with  the  actual 
sample.  Care  should  be  taken  to  ensure  the  fairness  of  this,  by  pumping 
to  such  an  extent  as  to  previously  empty  the  barrel  of  a  pump  ;  by  careful 
dipping  in  a  stream ;  and  by  avoiding  disturbing  the  sand  or  mud  at  the 
bottom  of  a  well,  spring,  or  rivulet.  In  rivers  the  sample  should  be  taken 
from  mid-stream,  avoiding  the  outlets  of  sewers  and  the  inlets  of  tributary 
streams.  The  vessel  in  which  the  sample  is  collected  should  be  filled  to 
within  half  an  inch  of  the  cork  or  stopper,  which  should  then  be  tied  down 
with  tape  or  string,  a  seal  being  placed  upon  the  knot,  and  another  upon 
the  top  of  the  stopper  or  cork  so  as  to  fix  the  string.  No  sealing-wax  or 
luting  should  be  placed  around  the  aperture  of  the  bottle. 

A  '  tie-on  '  luggage  label,  with  description  of  the  sample  and  the  date, 
should  be  affixed  to  the  neck  of  the  vessel,  and  secured  by  a  seal.  The  use 
of  adhesive  labels  is  attended  with  risk ;  they  are  easily  detached  when 
wetted,  and  an  ignorant  person  may  replace  a  label  on  a  wrong  bottle. 
Moreover,  the  purposive  transposition  of  labels  by  interested  persons  has 
been  known  to  occur. 

For  special  purposes,  and  where  a  mineral  analysis  is  required,  a  larger 
quantity  of  water  may  be  necessary — a  gallon  or  more. 

In  collecting  samples  of  water  for  bacteriological  examination,  flasks  of 
three  or  four  ounces'  capacity  maybe  employed.   These  are  cleansed,  plugged 


WATEB  '^75 

with  cotton-wool,  and  then  sterihsed.  The  plug  is  removed  by  means  of 
the  fingers  or  sterihsed  forceps  when  the  sample  is  collected,  taking  care 
not  to  touch  the  interior  of  the  neck  of  the  flask  with  the  fingers.  About 
an  ounce  of  the  water  is  introduced  by  means  of  a  sterilised  pipette,  and  the 
plug  replaced  ;  the  top  of  the  flask  may  then  be  secured  by  means  of  a 
caoutchouc  cap  which  has  been  kept  in  a  1  in  1000  solution  of  corrosive 
sublimate.  The  flasks  are  transported  with  difficulty,  since  the  sample 
should  at  no  time  be  allowed  to  touch  the  plug.  A  glass  bulb  with  a  slender 
neck  forms  a  better  receptacle  when  the  sample  has  to  be  transported  to  a 
distance  ;  the  bulb  being  hermetically  sealed,  as  recommended  by  Magnin 
and  Sterberg  ('  Bacteria,'  p.  175). 

In  the  case  of  spring  and  well  waters,  the  nature  of  the  soil,  subsoil,  and 
geological  characters  of  the  locality  should  be  carefully  noted. 

The  analysis  should  be  made  at  the  earhest  possible  opportunity.  If 
delayed,  ammonia  may  decrease,  or  nitrates  may  in  part  disappear,  odour  may 
be  lost,  and  deposit  may  take  place  owing  to  escape  of  carbonic  acid  gas  or 
absorption  of  oxygen,  or  from  both  causes. 

Gases 

A  determination  of  the  nature  of  these  is  not  frequently  necessary,  and  a 
quantitative  determination  of  each  of  them  is  seldom  of  much  service  for  the 
purposes  of  sanitation.  If  required,  special  precautions  are  necessary,  and 
some  of  the  operations  must  be  conducted  at  the  spring  or  well,  as  the  case 
may  be.  The  presence  of  any  special  odorous  gas  such  as  sulphuretted 
hydrogen  may  be  noted. 

Pkbliminaby  Examination 

Colour  and  Appearance. — This  is  best  observed  in  a  clear  glass  tube, 
two  feet  long  and  two  inches  in  diameter,  closed  at  one  end  by  a  plate  of  thin 
colourless  glass,  cemented  on  to  the  tube  with  an  uncoloured  cement.  By 
placing  the  tube  on  a  piece  of  white  printed  paper,  such  as  the  page  of  a 
book,  the  colour  of  the  water,  its  transparency  or  turbidity,  and  other  points 
connected  with  its  appearance,  may  be  readily  noticed.  By  only  half-filling 
the  tube,  so  that  the  lower  half  contains  water  and  the  upper  half  air,  and 
placing  the  tube  in  a  good  light,  and  backed  by  a  piece  of  white  paper,  further 
information  as  to  the  tint  of  the  water  will  be  obtained. 

Odour. — Some  waters  exhale  special  odours  even  in  the  cold,  such,  e.g. 
as  sulphuretted  waters.  When  no  odour  can  be  thus  perceived,  put  100  c.c. 
of  the  sample  into  a  clean  wide-mouthed  stoppered  bottle  holding  200  c.c,  and 
raise  the  temperature  to  about  100°  Fahr.  (38°  C).  Shake  vigorously,  remove 
the  stopper,  and  immediately  apply  the  nose  to  the  botttle.  Some  polluted 
waters  when  thus  treated  give  off  distinct  and  easily  recognisable  odours. 

Turbidity. — If  a  water  be  turbid,  the  nature  of  the  turbidity  should  be 
ascertained  ;  and  if  considerable,  its  quantity  should  be  determined.  For  the 
former  purpose  about  200  c.c.  of  the  water  may  be  placed  in  a  tall  conical 
glass,  and  the  deposit  allowed  to  subside,  the  vessel  being  kept  carefuUy 
covered  so  as  to  avoid  access  of  dust.  A  small  quantity  of  the  deposit  may 
then  be  removed  by  a  pipette  and  subjected  to  microscopical  examination.  The 
supernatant  water  may  then  be  siphoned  off  and  the  residue  treated  with 
hydrochloric  acid  so  as  to  ascertain  whether  it  is  chalky  matter  or  insoluble 
clay,  sand,  or  earth. 

In  order  to  determine  the  amount  of  suspended  matter,  a  definite  volume 
of  the  water — say  a  litre — is  filtered  through  a  tared  Swedish  paper  filter 

i2 


276  HYGIENE 

the  residue  dried  at  130°  C.  (100°  C.  Frankland)  and  weiglied.  On  deducting 
the  tare  of  the  filter,  and  multiplying  by  the  necessary  factor  to  reduce  the 
quantity  to  'grains  per  gallon,'  or  'parts  per  100,000'  if  desired,  the  'total 
suspended  matter '  is  obtained. 

By  incinerating  the  filter  with  the  deposit,  moistening  -^th  solution  of 
carbonate  of  ammonium,  and  drying  at  a  heat  below  dull  redness  (or  at. 
180°  C),  deducting  the  weight  of  a  similar  filter-ash,  the  '  mineral  suspended 
matter  '  is  obtamed.  The  difference  between  the  total  and  the  mineral  sus- 
pended matter  is  the  '  organic  suspended  matter.' 

MiCEOSCOPiCAL  Examination  of  Deposits 

This  important  operation  should  never  be  omitted  in  the  analysis  of  a 
water,  as  by  its  means  very  valuable  information  will  frequently  be  obtained, 
both  of  a  positive  and  of  a  negative  character :  positive  when  organisms  of 
definite  character  are  found  pointing  to  organic  pollution ;  and  negative 
when  a  turbidity  or  deposit  objectionable  to  the  eye  is  ascertained  to  be  due 
to  inert  mineral  matter  removable  by  a  simple  process  of  filtration. 

When  a  water  is  highly  tm'bid,  a  sufficient  quantity  of  deposit  may  readily 
be  obtained  for  microscopical  examination,  but  it  is  otherwise  when  the 
amount  of  tm-bidity  is  slight ;  and  this  is  most  commonly  the  case  with  an 
ordinary  drinking-water.  In  such  cases  the  method  recommended  by  Dr. 
Macdonald  may  be  employed.  ('  Microscop.  Exam,  of  Drinking  Water,'  p.  1.) 
A  tall  glass  vessel  holding  half  a  litre  or  a  litre  is  filled  with  the  sample,  and 
a  circular  disc  of  glass  resting  upon  a  horizontal  loop  at  the  end  of  a  long 
wire  is  let  down  to  the  bottom  of  the  glass,  and  the  whole  apparatus  is 
covered  and  set  aside  for  twenty-four  hours,  or  longer  if  necessary.  At  the 
end  of  this  time  the  water  is  syphoned  off,  only  leaving  a  thin  stratum  over  the 
glass  disc,  which  is  gently  raised,  and  laid  on  a  sheet  of  blotting-paper  so  as 
to  dry  its  under-surface,  when  it  may  at  once  be  transferred  to  the  stage  of 
the  microscope  after  covering  the  deposit  with  a  large  thin  covering-glass. 
Instead  of  a  disc  of  glass,  an  ordinary  microscope  shde  may  be  employed ; 
but  its  form  is  not  convenient  for  immersion.  Generally,  however,  it  suffices 
to  allow  the  sample  to  deposit  in  a  large  stoppered  collecting-bottle,  such  as 
a  Winchester  quart.  The  water  is  then  in  greater  part  syphoned  off  into 
another  bottle,  and  the  remainder  with  the  deposit  is  poured  into  a  conical 
glass,  which  is  covered  and  set  aside.  The  deposit  can  then  be  easily 
removed  by  a  pipette  in  sufficient  quantity  to  be  transferred  to  a  slide,  and 
submitted  to  microscopical  examination.  A  :|th  or  ^th  inch  objective  will 
usuaUy  suffice  for  the  examination,  and  many  organisms  are  better  seen  when 
a  lower  power  is  used.  It  must  be  remembered  that  this  examination  does 
not  supersede  a  bacteriological  examination  (see  p.  296). 

The  objects  thus  seen  are  very  varied :  angular,  crystalline,  and  rounded 
mineral  particles ;  the  pollen  of  flowers  ;  epidermic  and  deeper  tissues 
of  plants ;  fibres  of  linen,  cotton,  silk,  and  wood ;  vegetable  living  or  dead 
organisms,  from  the  minute  bacterium  to  strings  and  filaments  of  confervoid 
plants  ;  diatoms  ;  animal  fibres  and  organisms  of  varied  type  and  conforma- 
tion ;  ova  of  animals,  &c.  For  a  full  description  of  these  we  must  refer  to> 
other  works,  and  especially  to  the  one  already  referred  to :  '  A  Guide  to  the 
Microscopical  Examination  of  Drinking  Water,'  by  Dr.  J.  D.  Macdonald. 
2nd  ed.  1883. 

Under  certain  conditions  the  microscopical  exammation  of  water  may 
afford  valuable  negative,  if  not  positive,  results.  Thus,  for  example,  it  may 
be  important  to  ascertain  whether  a  water  contains  cholera-evacuations.     In 


WATEE  277 

this  case  plate  cultivations  may  be  made,  and  if  the  characteristic  Asiatic 
cholera  spirillum  be  obtained  and  distinguished  from  other  comma-shaped 
bacilli,  its  presence  will  indicate  that  the  water  contains  cholera- evacuations, 
whatever  be  the  view  held  as  to  the  causation  or  non-causation  of  cholera  by 
that  spirillum,  which  is  at  all  events  pretty  generally  accepted  as  being  an 
accompaniment  of  true  cholera. 

The  microzyme  test  as  hitherto  usually  employed  is  valueless,  viz.  the 
test  of  adding  a  few  drops  of  the  sample  of  water  to  a  small  quantity  of 
Pasteur's  nourishing  fluid  previously  boiled  in  a  sterilised  tube.  The  subse- 
quent milkiness  developed  in  the  liquid  only  proves  that  the  water  contains 
micro-organisms  or  their  spores,  and  these  are  present  even  in  ice  and 
in  ordinary  potable  waters  :  hence  no  results  of  real  value  are  obtainable  in 
this  way. 

Taste 

The  taste  and  palatability  of  a  water  is  important  to  be  noted.  It  is  not 
advisable,  however,  to  taste  a  water  when  there  is  reason  to  apprehend  that 
it  is  specifically  polluted. 

The  taste  of  a  water  depends  much  upon  the  quantity  and  quality  of  its 
saline  constituents  ;  and  still  more  on  the  gaseous  constituents.  Imperfectly 
oxidised  organic  impurities,  such  as  sewage,  may  confer  special  odours  on  a 
"water. 

Acidity,  Neutbality,  or  Alkalinity 

Most  waters  react  faintly  alkaline  to  dehcate  neutral  tint  litmus-papers. 
Eain- waters  and  peaty  waters  are  generally  slightly  acid  in  reaction. 

If  it  be  desired  to  determine  the  extent  of  acidity  of  a  water,  this  may 
be  done  by  placing  half  a  litre  in  a  flask  provided  with  a  reflux  condenser, 
and  boihng  the  water  vigorously  for  fifteen  minutes  or  so,  to  expel  carbon  di- 
oxide. The  acidity  is  then  determined  by  running  in  decinormal  soda  solution 
from  a  burette,  using  phenol-phthalein  as  an  indicator.  Some  analysts 
prefer  to  use  methyl-orange  to  determine  the  point  of  neutrality.  By  operat- 
ing on  two  separate  half-litres,  using  the  two  indicators  respectively,  a  dis- 
tinction may  be  made  between  mineral  and  organic  acids. 

Total  Solids  ok  Saline  Constituents 

A  platinum  basin  capable  of  holding  350  cubic  centimetres  is  cleaned, 
rinsed  with  distilled  water,  dried  in  an  air-oven  at  130°  C,  cooled  in  an  exsic- 
cator over  sulphuric  acid,  quickly  weighed,  and  the  tare  of  the  dish  noted. 
250  c.c.  of  the  water  under  examination  are  pipetted  into  the  basin,  and 
evaporated  to  dryness.  This  is  best  done  entirely  on  the  water-bath,  but  may 
be  partially  effected  over  a  naked  flame.  In  all  cases  the  completion  of  the 
evaporation  must  bo  effected  on  the  water-bath.  The  dish  with  its  contents 
when  dry  is  transferred  to  an  air-oven  heated  to  130°,  150°,  or  180°  C,  till  it 
practically  ceases  to  lose  weight,  or  for  a  definite  period,  say  half  an  hom-. 
Various  analysts  have  recommended  each  of  the  above-named  temperatures  ; 
but  the  temperature  of  130°  C.  is  the  one  most  commonly  adopted.  At  this 
temperature  hydrated  sulphate  of  calcium  readily  gives  up  three-fourths  of 
its  water,  and  undergoes  no  further  loss  below  200°  C. — an  inadmissible  tem- 
perature for  drying  a  water  residue.  This  last  temperature  is,  moreover, 
requisite  for  the  complete  dehydration  of  chloride  of  calcium.  But  whatever 
be  the  temperature  employed,  it  is  well  to  note  it  in  the  analytical  report,  so 
that  the  results  may  be  compared  with  those  of  other  analysts.     The  dish 


278  HYGIENE 

and  contents  are  again  cooled  in  the  exsiccator,  and  rapidly  weighed.  The 
dijfterence  between  the  new  weight  thus  obtained  and  the  original  weight  of 
the  dish  is,  of  course,  the  weight  of  the  sohds  in  250  c.c,  of  the  water,  which, 
multiplied  by  280  and  by  400  respectively,  gives  the  solids  in  grains  per  gallon 
and  in  parts  per  100,000  respectively. 

Dr.  Frankland  recommends  the  evaporation  of  500  c.c.  of  the  sample, 
with  special  precautions,  and  the  drying  of  the  evaporated  residue  in  the 
water-oven  at  approximately  100°  C.  for  three  hours,  in  order  to  obtain  the 
total  solids  ('  Water  Analysis,'  p.  17).  Mr.  Wanklyn,  on  the  other  hand,  uses 
70  c.c.  only,  and  dries  for  ten  minutes  only  in  the  water-oven.  His  published 
analyses  by  this  method,  which  he  says  are  '  very  concordant,'  show  weigh- 
ings made  apparently  to  the  extraordinary  minuteness  of  0*01  milligramme. 
70  c.c.  is  too  small  a  quantity  to  use  when  anything  nearer  than  a  rough 
approximation  to  total  solids  is  desired. 

Loss  on  Ignition  (also  sometimes  termed  '  organic  matter  and  water  of 
hydration  '). — This  determination  is  obtained  with  the  greatest  accuracy  by 
placing  the  platinum  basin  with  its  solid  contents  resting  on  a  clay  triangle 
inside  a  larger  dish,  over  which  is  suspended  at  a  short  distance  a  plate 
of  platinum,  and  gently  heating  the  outer  dish  by  means  of  an  argand  burner. 
The  outer  dish  may  ordinarily  be  dispensed  with,  care  being  taken  to  avoid 
a  heat  exceeding  that  of  dull  redness,  otherwise  alkaline  chlorides  may  be 
volatilised.  The  heat  must  be  continued  till  all  sooty  particles  are  dissipated. 
The  evolution  of  ruddy  fumes,  indicating  the  presence  of  nitrates  or  nitrites, 
is  noted,  and  also  the  production  of  special  odours,  such  as  those  of  burning 
nitrogenous  organic  matter.  In  this  way  valuable  information  may  be 
obtained.  With  care,  no  loss  occurs  from  the  decomposition  of  carbonates  ; 
but  it  is  always  advisable  to  moisten  the  incinerated  residue  with  a  solution 
of  carbonate  of  ammonium,  dry,  and  again  very  gently  incinerate,  so  as  to 
insure  the  full  carbonation  of  the  residue  ;  and  when  the  water  abounds  in 
nitrates  this  treatment  with  carbonate  of  ammonium  is  indispensable.  When 
cold,  the  weight  of  the  dish  and  its  contents  deducted  from  the  similar 
weight  of  the  dish  plus  the  total  solids  gives  the  loss  on  incineration,  which 
is  then  calculated  into  parts  per  100,000,  or  grains  per  gallon  if  desired,  by 
multiplying  by  400  or  by  280  respectively.  It  is  customary  to  disparage  the 
value  of  this  determination,  but  it  is  one  which  an  experienced  analyst  will 
never  omit ;  and  by  observing  the  manner  in  which  the  incmeration  progresses, 
the  gases  and  vapours  given  off,  &c.,  much  valuable  information  may  be 
gained  as  to  the  kind  of  organic  matter  present  in  the  water. 

When  the  water  contains  considerable  quantities  of  nitrates,  a  correction 
is  necessary  owing  to  the  substitution  of  the  radical  CO2  for  the  radical  N2O5 
in  the  nitrates  ;  CaO.  NgOg,  for  example,  having  the  molecular  weight  164, 
becomes  CaO.  CO2,  having  the  molecular  weight  100.  The  rule  is  to  deduct 
from  the  experimental  loss  on  ignition  2-29  for  each  unit  of  '  nitrogen  as 
nitrates  and  nitrites '  present,  or  0'59  for  each  unit  of  nitric  acid,  N2O5.  In 
the  case  of  many  magnesian  waters,  the  loss  on  ignition  is  increased 
by  the  loss  of  hydrochloric  acid  during  evaporation,  aqueous  chloride 
of  magnesium  being  converted  on  evaporation  into  magnesia,  with  loss  of 
hydrochloric  acid. 

Chloeine 

This  is  best  titrated  by  means  of  a  standard  solution  of  nitrate  of  silver, 
each  1  c.c.  of  which  will  precipitate  O'OOl  gramme  of  combined  chlorine. 
The  solution  is  prepared  by  dissolving  4*79  grammes  of  recrystalhsed  nitrate 
of  silver  in  distilled  water,  and  making  up  with  additional  water  to  the^ 


WATER  270 

volume  of  a  litre.  Its  exact  strength  is  determined  from  time  to  time  by 
setting  it  against  a  standard  solution  of  chloride  of  sodium,  containing  1"648 
gramme  of  ignited  (not  fused)  clean  rock-salt  crystals,  in  a  litre  of  distilled 
water.  Or  pure  chloride  of  sodium  may  be  prepared  by  precipitating 
a  saturated  solution  of  common  salt  by  passing  a  current  of  hydrochloric 
acid  gas  into  it,  and  then  collecting,  rinsing  with  distilled  water,  and  drying 
at  300°  C.  the  crystals  which  have  been  thrown  down  from  the  solution. 

In  performing  the  analysis,  50  c.c.  of  the  water  is  pipetted  into  a  white 
porcelain  dish,  and  one  or  two  drops  of  a  half- saturated  solution  of  neutral 
yellow  chromate  of  potassium  added.  The  chromate  solution  when  acidu- 
lated with  nitric  acid  must  remain  perfectly  clear  when  a  drop  of  the  solution 
of  nitrate  of  silver  is  added  to  it,  proving  the  absence  of  chlorides.  If  now 
the  standard  solution  of  nitrate  of  silver  be  run  from  a  burette  into  the 
water  to  be  analysed,  and  to  which  the  chromate  has  been  added,  a  red  pre- 
cipitate of  chromate  of  silver  will  be  formed  around  the  inflowing  solution, 
but  will  quickly  disappear  on  stirring  the  liquid  in  the  dish,  the  red  chromate 
of  silver  being  decomposed,  and  white  chloride  of  silver  formed,  so  long  as 
any  chloride  remains  in  solution.  But  when  the  chlorine  is  all  converted 
into  chloride  of  silver,  the  slightest  excess  of  the  standard  solution  instantly 
strikes  a  red  colour,  due  to  the  permanent  precipitation  of  chromate  of 
silver.  Hence  the  chromate  acts  as  an  indicator,  and  when  the  slightest 
tinge  of  red  colour  is  visible  on  stirring  the  Uquid,  the  reaction  is  terminated, 
and  the  quantity  of  standard  solution  that  has  been  added  is  read  off.  The 
number  of  cubic  centimetres  added  multiplied  by  1*4  gives  the  grains  of 
chlorine  per  gallon,  and  by  2  the  parts  of  chlorine  per  100,000.  The  quan- 
tity of  chlorine  multiplied  by  1*648  gives  the  amount  of  chloride  of  sodium 
which  is  equivalent  to  the  combined  chlorine  present. 

It  is  well  to  discharge  the  colour  of  the  liquid  in  the  dish  on  the  comple- 
tion of  the  titrations  by  adding  a  few  drops  of  a  solution  of  chloride  of  sodium,, 
and  repeating  the  titration  in  another  dish  on  a  fresh  quantity  of  the  water. 
When  the  two  dishes  are  viewed  side  by  side,  any  shade  of  difference  in  the 
colour  of  the  solutions  will  be  easily  perceptible. 

Some  analysts  prefer  to  use  a  decinormal  silver  solution  (17  grammes  of 
nitrate  of  silver  per  litre)  and  operate  on  a  large  volume,  say  250  c.c,  of  the 
water.  Each  1  c.c.  of  this  solution  precipitates  '00355  gramme  of  chlorine  ; 
hence  if  250  c.c.  of  water  be  used  for  titration,  the  number  of  cubic  centimetres 
of  silver  solution  multiplied  by  0*994  gives  the  grains  of  chlorine  per  gallon, 
or  by  1*42  the  parts  of  chlorine  per  100,000  of  water. 

Dr.  Frankland  uses  a  solution  of  half  the  strength  here  recommended, 
using  50  c.c.  of  the  water  for  titration.  Each  1  c.c.  of  his  nitrate  of  silver 
solution  =  0*0005  gramme  chlorine  ('  Water  Analysis,'  p.  20). 

NiTEATES 

1.  Indigo  Process. — A  standard  solution  of  indigo  is  prepared  by  dissolv- 
ing commercial  indigo -carmine  in  water  containing  5  per  cent,  by  volume  of 
sulphuric  acid,  and  boiling  for  some  time  so  as  to  sterilise  the  solution.  It 
is  then  standardised  against  a  very  dilute  solution  of  nitrate  of  potassium, 
which  may  be  conveniently  made  of  such  a  strength  that  1  c.c.  =  •0001 
gramme  NoO^,  or  a  solution  containing  0*187  gramme  nitrate  of  potassium 
in  a  litre  of  water.  In  diluting  the  indigo  solution  to  the  proper  strength, 
distilled  water  containmg  5  per  cent,  by  volume  of  sulphuric  acid  should  be 
used.  When  thus  prepared  the  solution  keeps  well.  The  process  is  conducted 
as  follows : 


280  HYGIUNE 

20  c.c.  of  the  water  (or  to  standardise  the  indigo,  10  c.c.  of  nitrate  of 
potassium  solution  and  10  c.c.  distilled  water)  are  measured  into  a  beaker 
of  about  100  c.c.  capacity,  standing  in  a  small  flat  porcelain  dish ;  1  c.c.  of 
standard  indigo  solution  is  run  in  from  a  burette,  and  then  21  c.c.  of  strong 
sulphuric  acid  (free  from  oxides  of  nitrogen  and  of  sp.  gr,  l'8-4)  are  cautiously 
poured  in,  so  as  not  to  mix  with  the  liquid  in  the  beaker.  As  soon  as  the  blue 
colour  of  the  indigo  begins  to  fade,  the  mixtm-e  is  stirred,  when  the  tempe- 
rature rises  to  120°-130°  C.  The  indigo  solution  is  then  rapidly  run  in 
from  the  burette  till  a  permanent  blue  colour  remains.  The  volume  of 
indigo  solution  required  is  noted  :  say  10  c.c.  A  fresh  20  c.c.  of  water  is 
taken,  10  c.c.  of  indigo  solution  added,  and  a  volume  of  sulphuric  acid  equal 
to  the  whole  (30  c.c.)  cautiously  added,  and  the  mixture  stirred  as  soon  as 
decoloration  commences. 

The  process  is  repeated  until,  in  the  final  experiment,  the  volume  of  in- 
digo solution  added  to  the  20  c.c.  water  in  the  beaker,  on  mixing  Avith  a 
volume  of  sulphuric  acid  equal  to  the  bulk  of  water  plus  indigo  solution, 
leaves  a  faint  blue  tint  after  stirring.  In  each  experiment  the  bulk  of  acid 
used  must  equal  the  volume  of  liquid  to  which  it  is  added,  in  order  to  attain 
the  proper  temperature  on  mixing.  The  number  of  c.c.  of  indigo  solution 
used  multiplied  by  0-5  gives  parts  per  100,000,  or  by  0-35,  grains  per  gallon 
of  N2O5. 

In  cold  weather  it  is  advisable  to  slightly  warm  the  mixture  of  indigo 
solution  and  water  before  adding  the  acid. 

Should  a  water  require  more  than  about  10  c.c.  indigo  solution  for  20  c.c. 
water,  the  sample  should  be  appropriately  diluted.  For  very  small  quantities 
of  nitrates  a  dilute  solution  of  indigo  may  be  used — -^th  or  y  o^h  the  strength 
of  the  above  solution — the  operation  bemg  conducted  in  the  manner  already 
described. 

2.  Phenol- Sulphuric  Acid  Method. — This  method  is  simple  in  its  applica- 
tion, and  yields  good  results.  Phenol- sulphuric  acid  is  prepared  by  melting 
absolute  phenol,  and  pouring  two  parts,  by  measure,  of  the  liquefied  phenol 
into  five  volumes  of  pure  concentrated  sulphuric  acid  free  from  nitrates,  when 
the  whole  is  digested  for  eight  hours  in  a  water-bath  kept  boiling.  The 
mixture  is  then  allowed  to  cool,  and  to  each  two  volumes  of  the  liquid  is 
added  one  and  a  half  volumes  of  distilled  water,  and  half  volume  of  pure 
strong  hydrochloric  acid  solution.  The  light  brown  solution  thus  obtained  is 
ready  for  use.  The  following  is  a  good  mode  of  procedure  ('  Chem.  News,' 
1890,  vol.  61,  p.  15). 

10  c.c.  of  the  water  under  examination  and  10  c.c.  of  a  standard  solu- 
tion of  nitrate  potassium  (0'7215  gramme  per  litre)  are  pipetted  into  two 
small  beakers,  and  placed  near  the  edge  of  a  hot  plate.  When  nearly 
evaporated,  they  are  removed  to  the  top  of  the  water-oven  and  left  there  till  they 
are  evaporated  to  complete  dryness.  As  this  operation  usually  takes  about  an 
hour  and  a  half,  it  is  better,  when  time  is  an  object,  to  evaporate  to  dryness 
in  a  platinum  dish  over  steam.  The  residue  in  each  case  is  then  treated 
Avith  1  c.c.  of  the  phenol-sulphuric  acid,  and  the  beakers  are  placed  on  the 
top  of  the  water-oven.  If  the  water  under  examination  contains  a  large 
quantity  of  nitrates,  the  liquid  speedily  assumes  a  red  colour,  which  in  a 
good  water  will  not  appear  for  about  ten  minutes.  After  standing  for  fifteen 
minutes  the  beakers  are  removed,  the  contents  of  each  washed  out  successively 
into  a  100-c.c.  measuring-glass,  a  slight  excess  (about  20  c.c.)  of  ammonia 
solution  (sp.  gr.  0*96)  added,  the  100  c.c.  made  up  by  the  addition  of  water, 
and  the  yellow  liquid  transferred  to  a  Nessler  glass  (6  in.  x  1^  in.).  The 
more  strongly  coloured  liquid  is  then  partly  transferred  to  the  measuring- 


WATEB  281 

glass  again,  and  the  tints  compared  a  second  time.  In  this  way  the  tints 
■are  adjusted,  and,  when  as  far  as  possible  matched,  the  liquid  that  has 
been  partially  removed  is  made  up  to  the  100  c.c.  mark  with  water,  and, 
after  well  mixing,  finally  compared.  If  not  of  exactly  the  same  tint,  a  new 
liquid  can  at  once  be  made  up,  probably  of  exactly  the  same  tint,  as  the  first 
experiment  gives  very  nearly  the  number  of  c.c.  of  the  one  equivalent  to 
the  100  c.c.  of  the  other.  Each  1  c.c.  of  the  nitrate  solution  used  =  0-0001 
gramme  N. 

In  the  case  of  very  good  waters,  20,  50,  or  more  c.c.  should  be  evaporated 
to  a  small  bulk,  rinsed  into  a  small  beaker,  and  evaporated  to  dryness,  and 
treated  as  above — only  5  c.c.  of  the  standard  nitrate  of  potassium  (=  0*5  N 
in  100,000)  being  taken.  In  the  case  of  very  bad  waters,  10  c.c.  should  be 
pipetted  into  a  100  c.c.  measuring-flask,  and  made  up  to  the  mark  with 
distilled  water,  then  10  c.c.  of  the  well-mixed  liquid  (=  1  c.c.  original  water) 
withdrawn,  and  treated  as  above. 

3.  Aluminium  Process. — This  is  the  process  recommended  by  Mr.  Wanklyn. 
It  is  thus  performed :  Caustic  soda  is  prepared  free  from  nitrates  by  dissolving 
metallic  sodium  in  water,  2  grammes  of  the  metal  being  used  for  each  100 
c.c.  distilled  water,  which  is  then  boiled  to  expel  ammonia.  A  definite  volume, 
say  50  c.c.  or  100  c.c,  of  the  water  to  be  examined  is  mixed  with  its  own 
volume  of  this  soda  solution,  and  a  piece  of  aluminium-foil,  more  than  the 
liquid  will  dissolve,  is  placed  in  the  mixture  and  allowed  to  remain  for  several 
hours.  The  hquid  is  then  distilled,  and  in  the  distillate  the  ammonia 
formed  by  reduction  of  the  nitrates  is  titrated  by  means  of  Nessler's  solution. 
Each  unit  of  ammonia  found  corresponds  to  0-8235  unit  of  '  nitrogen  as 
nitrates,'  or  to  3'176  units  of  N2O5.  If  100  c.c.  of  water  were  employed,  by 
anultiplying  the  results  obtained  by  700  the  number  of  grains  per  gallon  is 
obtained  ;  or  by  moving  the  decimal  three  places  to  the  right,  we  get  parts 
per  100,000. 

In  using  the  process  Dr.  Frankland  advises  the  use  of  a  10  per  cent, 
solution  of  soda,  made  free  from  nitrates  by  dissolving  4  inches  square  of 
aluminium-foil  in  it,  and  boiling  off  one-third  of  the  liquid.  In  the  actual 
performance  of  the  analysis  100  c.c.  of  the  water  are  treated  with  10  c.c.  of 
the  above  soda  solution,  evaporated  to  one-fourth,  and  then  treated  with 
2  inches  square  of  aluminium-foil  for  six  hours  before  distilling  off  the 
ammonia  ('  Water  Analysis,'  p.  30). 

4.  The  Zinc-Copper  Couple  Method. — This  method,  devised  by  Dr. 
Gladstone  and  Mr.  Tribe,  depends  upon  the  electrolytic  reduction  of  nitrates 
io  ammonia  by  means  of  a  couple  of  the  two  metals  copper  and  zinc, 
which  is  prepared  as  follows :  A  mixture  of  2  grains  of  finely  divided  reduced 
•copper  with  18  grains  of  coarse  zinc  filings  is  introduced  into  a  2  oz.  flask 
fitted  with  a  cork,  through  which  passes  a  tube  drawn  out  to  a  capillary 
-opening.  The  flask  is  heated  over  a  burner  till  the  zinc  begins  to  soften, 
shaking  gently  all  the  time  to  ensure  thorough  mixture  of  the  two  metals, 
and  to  prevent  any  part  being  overheated.  The  mass,  when  the  operation 
is  finished,  should  consist  of  greyish-black  grains,  without  metallic  lustre. 
If  the  mass  has  a  brassy  tint,  or  if  the  zinc  filings  retain  their  form,  the 
product  must  be  rejected.  As  soon  as  the  desired  result  is  obtained,  the 
flask  is  removed  from  the  flame,  continuing  the  agitation  for  a  few  seconds 
to  prevent  fusion.  The  point  of  the  capillary  tube  is  then  sealed,  and  the 
flask  allowed  to  cool. 

In  performing  the  analysis  250  c.c.  of  the  water  may  be  evaporated  over 
.a  naked  flame  to  about  the  volume  of  25  c.c,  a  fragment  of  quicklime  about 
.the  size  of  a  hemp  seed  added,  and  the  evaporation  renewed  till  the  bulk  is 


282  HYGIENE 

reduced  to  6  or  7  cc  The  whole  is  then  rinsed  into  an  8  oz.  distilhng-flask, 
and  the  requisite  amount  of  zinc-copper  couple  added.  The  flask  is  closed  with 
a  cork,  and  attached  to  a  small  Liebig's  condenser,  and  the  water  nearly  all 
distilled  off.  Hot  distilled  water  is  added  at  intervals,  and  the  distillation 
renewed  till  100  cc.  of  distillate  is  obtained.  This  after  appropriate  dilution 
of  a  fraction,  say  5  cc,  made  up  to  50  cc,  is  then  nesslerised. 

5.  FranklancV s  Process. — Dr.  Frankland  estimates  the  total  amount  of 
nitrogen  present  in  the  form  of  nitrates  and  nitrites  by  a  method — that  of 
Crum — based  upon  the  reduction  of  the  acids  of  these  salts  by  means  of 
mercury.  A  litre,  or  even  half  a  litre,  of  the  water  is  evaporated  to  a  small 
bulk,  sulphate  of  silver  is  added  to  precipitate  chlorides,  and  the  mixture  is 
filtered.  When  the  water  contains  nitrites,  these  are  converted  into  nitrates 
before  the  evaporation  by  means  of  permanganate  of  potassium.  The  filtered 
liquid  is  evaporated  to  a  bulk  of  2  or  3  cc,  and  transferred  to  a  glass  tube 
open  at  one  end,  and  furnished  with  a  stopcock  and  fmuiel-shaped  mouth  at 
the  other  end.  The  tube  is  filled  with  mercury,  the  stopcock  being  closed, 
inverted  in  the  mercury  trough,  so  that  the  funnel-shaped  mouth  is  upwards, 
and  the  Avater  residue  is  introduced  into  the  funnel  and  run  into  the  tube, 
the  vessel  in  which  the  residue  is  contained  being  rinsed  Avith  Avater,  and 
then  3  or  4  cc  of  strong  sulphuric  acid  (free  from  nitro-compounds)  are 
introduced  into  the  fmmel  and  tube.  Care  must  be  taken  to  avoid  the 
introduction  of  air  into  the  tube,  which  is  noAV  closed,  Avhilst  in  the  trough, 
by  means  of  the  thumb.  The  tube  is  now  removed  from  the  trough  and 
vigorously  shaken  by  a  semi-rotary  motion,  so  as  to  keep  an  unbroken 
column  of  at  least  an  inch  of  mercury  below  the  acid  liquid.  The  pressure 
exerted  by  the  liberated  nitric  oxide  is,  as  far  as  possible,  resisted  by  the 
opposing  pressure  of  the  thumb.  At  the  end  of  five  minutes  the  reaction  is 
completed,  the  gas  is  transferred  under  mercury  to  a  suitable  eudiometer, 
and  its  volume  measured. 

Nitrites 

These  are  best  determined  by  meta-phenylene  diamine,  the  hydrochlorate 
of  AA^liich  may  noAV  be  purchased  in  a  state  of  suificient  purity  for  the  analysis. 
1  gramme  of  the  salt  is  dissolved  in  200  cc.  of  water  acidulated  Avith  sul- 
phuric acid.  The  other  solutions  required  are — dilute  sulphuric  acid  (1  vol. 
acid  to  2  vol.  water),  and  a  solution  of  nitrite  of  potassium.  This  solution  is 
prepared  by  dissohing  0*405  gramme  recrystallised  nitrite  of  silver  in  hot 
water,  precipitating  Avith  a  slight  excess  of  chloride  of  potassium,  cooling, 
and  making  up  Avith  distilled  Avater  to  a  litre  ;  allowing  the  chloride  of  silver 
to  settle  and  decanting.  For  use,  100  cc  of  the  clear  liquid  is  diluted  with 
distilled  Avater  to  a  litre.  Each  1  cc  of  the  diluted  solution  is  the  equivalent 
of  O'Ol  milligramme  of  N2O.;. 

To  estimate  the  nitrites  1  cc  of  each  of  the  first  two  solutions  is  added 
to  100  cc  of  the  Avater  placed  in  a  nesslerising  cylinder,  Avhen,  if  nitrites  h& 
present,  a  yellowish-red  colour  is  produced.  This  must  not  be  deeper  than 
a  just  clearly  recognisable  tint  :  if  deeper  than  this,  a  smaller  quantity  of  the 
water  than  100  cc  must  be  taken  and  diluted  with  distilled  Avater  to  this 
volume.  The  tint  is  compared  Avith  that  given  by  a  definite  quantity  of  the 
standard  solution  of  nitrite  made  up  to  100  cc  and  treated  AA'ith  1  cc 
each  of  the  meta-phenylene  diamine  solution  and  the  dilute  sulphuric  acid. 
Supposing  100  cc  of  the  Avater  gives  the  same  tint  as  9  cc  of  the  standard 
nitrite  solution  in  100  cc  of  hquid:  then  O'Ol  x  9=0-09  milhgramme  N^Og 
in  the  100  cc  and  0-09  x  •7=0-063  grain  N,0:j  per  gallon.  The  N0O3  xO-37 
=N  :  thus  the  above  water  contained  0-003  x  0-37=0-023  grain  N  as  NoOg. 


WATEE  283 

per  gallon.     This  test  is  not  readily  applicable  when  the  water  is  coloured, 
as,  e.g.,  with  peaty  matter. 

Dr.  Thresh  has  recently  devised  a  method  of  determining  the  quantity  of 
nitrites  in  water  by  means  of  iodide  of  potassium  in  an  atmosphere  of  coal 
gas,  and  titrating  the  hberated  iodine  by  means  of  thiosulphate  (hyposulphite) 
of  sodium  and  starch.  The  apparatus  used  is  the  one  which  he  has  devised 
for  the  estimation  of  free  oxygen  in  waters.  According  to  Dr.  Thresh,  the 
results  obtained  are  accurate  ('  Jour.  Chem.  Soc'  vol.  57, 1890,  Trans,  p.  185). 

Ammonia 
See  *  The  Albuminoid  Ammonia  Process,'  p.  285. 

Oeganic  Matter 

This  is  the  most  important  constituent  to  be  determined  from  a  sanitary 
point  of  view,  and  the  one  as  to  which  the  most  serious  discrepancies  of 
opinion  have  existed.  There  are  three  chief  methods  of  estimating  organic 
matter  in  water,  or  rather  of  estimating  the  relative  quantities  in  different 
waters  ;  for  few  will  claim  that  any  known  method  will  estimate  the  absolute 
quantity  of  organic  matter  present.  These  methods  are  the  combustion  pro- 
cess, commonly  known  as  Frankland's,  and  its  modifications  ;  the  albuminoid 
ammonia  process,  devised  by  Mr.  Wanklyn ;  and  Forchammer's  permanganate 
process.  Eecently,  a  new  method,  that  of  Kjeldahl,  has  been  introduced. 
These  methods  will  now  be  described. 

Frankland's  Process. — Dr.  Frankland  claims  for  his  process  that  it  is  the 
only  one  which  determines  with  anything  like  precision  the  total  quantity  of 
organic  carbon  and  organic  nitrogen  present  in  a  water,  i.e.  the  carbon  in 
forms  other  than  that  of  carbonates,  and  the  nitrogen  in  other  forms  than 
those  of  ammonia,  nitrites,  or  nitrates  ;  and  hence  that  it  affords  a  measure 
of  the  carbon  and  nitrogen  present  in  the  organic  compounds  present,  and 
so,  indirectly,  of  the  absolute  quantity  of  organic  matter  in  a  water.  In  this 
process  the  organic  carbon  is  oxidised  and  obtained  as  carbon  dioxide,  and  the 
organic  nitrogen  is  hberated  in  the  free  gaseous  state  and  measured.  It  is 
further  claimed  that  the  proportion  of  organic  carbon  to  organic  nitrogen 
enables  the  analyst  to  judge  as  to  whether  the  organic  matter  is  of  vegetable 
or  animal  origin,  since  animal  matters  as  a  rule  are  richer  in  nitrogen  than 
vegetable  matters.  But  every  one  of  these  claims  has  been  vehemently  con- 
tested. 

In  the  first  place,  although  it  is  indubitable  that  when  stable  carbon 
compounds,  such  as  quinine  and  sugar,  are  added  to  a  water,  the  carbon 
in  the  latter  and  the  carbon  and  nitrogen  in  the  former  can  be  deter- 
mined by  the  Frankland  combustion  process  with  a  reasonable  amount  of 
accuracy,  it  is  by  no  means  certain  that  the  minute  quantities  of  carbon  and 
nitrogen  present  in  sewage  can  be  determined  with  anything  like  the  same 
amount  of  precision  ;  and  it  is  possible  that,  during  the  necessary  evaporation 
to  dryness  of  a  large  volume  of  water,  unstable  and  readily  decomposable 
bodies  may  undergo  decomposition,  and  be  lost  so  far  as  analysis  is  concerned. 
This  criticism  has  never  been  satisfactorily  refuted ;  and  altJaough  in  a  great 
majority  of  instances  it  may  have  no  value,  it  is  probable  that  in  some  in- 
stances it  may  have  greatf  orce.  As  to  the  value  of  the  assertion  that  a 
higher  proportion  of  nitrogen  to  carbon  is  found  in  animal  as  compared  with 
vegetable  matter,  the  whole  validity  of  the  comparison  based  on  the  ratios 
of  these  two  elements  present  rests  upon  the  assumption  that  the  absolute 


284  HYGIENE 

amounts  of  carbon  and  nitrogen  are  both  determined  ;  and,  as  has  been  ah-eady 
intimated,  this  has  not  been  proved.  It  is  remarkable,  too,  that  in  sea-water 
the  ratio  of  organic  nitrogen  to  organic  carbon  is  very  high  indeed — an  asserted 
characteristic  of  animal,  and  assuredly  of  deleterious,  organic  matter.  Yet  it 
can  scarcely  be  supposed  that  the  organic  matter  in  sea-water  is  chiefly  or 
entirely  noxious  animal  matter,  any  more  than  the  organic  matter  in  river- 
water  unpolluted  with  sewage.  Yet  the  Frankland  process  would  per  se  lead 
us  to  suppose  that  sea-water  is  dangerously  polluted  with  animal  matter. 
Frankland's  organic-combustion  process  is  one  which  requires  great  care  and 
exactitude  in  its  execution.  It  cannot  be  entrusted  to  the  hands  of  any  but 
those  accustomed  to  its  working,  and  skilled  in  minute  gas  analysis.  Hence 
it  is  seldom  employed  by  the  Medical  Officer  of  Health.  For  a  full  description 
of  its  operations  we  must  refer  our  readers  to  the  description  of  its  author, 
Dr.  Frankland  ('  Journ.  Chem,  Soc'  vol.  21,  p.  77 ;  '  Sixth  Eeport  of  Elvers 
Pollution  Commissioners,'  p.  501,  and  '  Water-Analysis  :  '  London,  1890). 
The  outlines  of  the  process  are  as  follows. 

A  Htre  of  the  water  is  mixed  with  30  c.c.  of  a  freshly  saturated  solution  of 
sulphurous  acid,  and  boiled  for  a  few  minutes.  Such  a  solution  of  sulphur- 
ous acid  can  be  readily  and  rapidly  prepared  by  passing  the  gas  from  a 
syphon  of  liquefied  sulphur  dioxide  into  distilled  water ;  and  these  syphons 
are  now  articles  of  commerce.  By  the  above  treatment  the  carbonates  are 
decomposed  and  carbonic  acid  expeUed.  When  the  water  contains  httle  or 
no  carbonate,  0*2  gramme  of  sulphite  of  sodium  are  added  before  evapora- 
tion, to  ensure  the  saturation  of  any  sulphuric  acid  formed  during  the 
evaporation  to  dryness.  A  few  drops  of  a  solution  of  ferric  chloride  are  also 
added  before  evaporation ;  and  thus  the  whole  of  the  nitrogen  existing  as 
nitrates  and  nitrites  is  expelled. 

The  dry  residue  is  mixed  with  a  few  grammes  of  chromate  of  lead,  and 
the  mixture  is  transferred  to  a  combustion  tube  sealed  at  one  end.  The 
remainder  of  the  tube  is  then  charged  with  cupric  oxide  and  copper  turnings 
in  the  manner  usually  followed  in  making  an  organic  combustion.  The  open 
end  of  the  tube  is  then  drawn  out  in  the  blowpipe  flame,  and  connected  with 
a  Sprengel's  mercury  pump  by  means  of  a  piece  of  caoutchouc  tubing,  and 
the  connection  immersed  in  a  vessel  of  water.  The  front  part  of  the  tube  is 
then  heated,  and  the  pump  worked  for  five  or  ten  minutes  until  a  good 
vacuum  is  obtained.  An  inverted  glass  tube,  filled  with  mercury,  is  now 
placed  over  the  dehvery  end  of  the  tube  of  the  pump  to  coUect  the  gaseous 
products,  and  the  combustion  is  made  in  the  ordhiary  manner,  an  hour 
being  usually  taken  for  the  operation,  when  it  will  be  found  that  unless  much 
organic  matter  is  present  in  the  water  no  gas  will  have  passed  into  the 
collecting-tube  ;  and  the  pump  has  to  be  again  worked  for  five  or  ten  minutes 
to  transfer  the  gas  into  the  collecting-tube.  The  quantities  of  carbonic  acid 
and  nitrogen  gases  are  then  respectively  determined  in  the  gaseous  mixture 
by  the  ordinary  process  of  gas  analysis.  The  quantities  of  gases  thus  ob- 
tained represent  the  organic  carbon  and  organic  nitrogen  and  the  nitrogen 
of  ammonia  present  in  a  litre  of  water.  The  ammonia  is  separately  deter- 
mined (see  p.  286),  and  the  corresponding  quantity  of  nitrogen  deducted  from 
tbe  total  combined  nitrogen. 

For  correction  for  errors  of  manipulation  and  apparatus  we  must  refer 
our  readers  to  the  original  paper  ;  and,  indeed,  no  unskilled  analyst,  nor  any- 
one unaccustomed  to  the  necessary  manipulations  and  the  sources  of  error, 
should  undertake  to  perform  an  analysis  by  the  Frankland  combustion 
process— an  operation  at  all  times  requiring  gi*eat  delicacy  of  manipulation. 

Dupre  and  Hake  ('  Journ.  Chem.  Soc'  1879,  p.  159)  have  simphfied  the 


WATER  285 

combustion  process,  without  sacrificing  its  delicacy  and  accuracy.  An  appro- 
priate quantity  of  the  water  to  be  analysed  is  evaporated  to  dryness  after 
acidification  with  phosphoric  acid,  and  the  residue  transferred  to  a  platinum 
boat  and  then  placed  in  a  combustion  tube  24  inches  in  length,  prepared  as 
follows  : — The  tube  is  filled  for  half  its  length  with  granulated  cupric  oxide, 
which  is  kept  in  position  by  an  asbestos  plug.  The  tube  is  then  drawn  out 
and  bent  downwards  in  front  to  an  angle  of  120°,  and  is  then  attached  to  a 
Pettenkofer's  absorption  tube  charged  with  baryta-water,  the  other  being 
attached  by  means  of  a  flexible  tube  to  a  reservoir  of  oxygen  gas.  The  tube 
is  heated  to  redness,  whilst  a  stream  of  oxygen  is  passed  through  it  until  the 
issuing  gas  ceases  to  render  the  baryta-water  turbid.  The  posterior  end  of 
the  tube  is  now  opened  and  the  platinum  boat  containing  the  water  residue 
is  quickly  inserted.  Another  Pettenkofer's  tub©  charged  with  a  2  per  cent, 
solution  of  subacetate  of  lead  is  changed  for  the  baryta-water  tube  ;  and  the 
combustion  is  then  made  in  a  stream  of  oxygen.  Finally,  the  turbidity  pro- 
duced by  the  carbon  dioxide  evolved  is  compared  with  that  produced  in  the 
subacetate  of  lead  solution  by  a  known  and  comparable  quantity  of  carbon 
dioxide  in  a  modified  Mill's  colorimeter.  For  details  we  refer  to  the  original 
paper. 

KjeldahVs  Method.' — This  has  been  recently  used  for  the  determination  of 
the  total  combined  nitrogen,  except  nitrates,  in  natural  waters  (Drown  and 
Martin,  '  Chemical  News,'  1889,  vol.  59,  p.  272).  It  is  employed  as 
follows  :  500  c.c.  of  the  water  are  placed  in  a  round-bottomed  flask  of  about 
30  oz.  or  900  c.c.  capacity  attached  to  a  condenser,  and  200  c.c.  are  dis- 
tilled and  nesslerised  for  ammonia,  as  in  the  albuminoid  ammonia  process. 
To  the  remaining  300  c.c.  of  water  in  the  flask,  after  coohng,  10  c.c.  of 
nitrogen-free  sulphuric  acid  are  added,  and  the  whole  gently  agitated  so  that 
the  acid  may  mix  with  the  water.  The  flask  is  then  placed  at  an  inclination 
on  wire  gauze  on  an  appropriate  support,  and  the  hquid  is  boiled  down  till 
the  oily  residue  is  colourless  or  pale  yellow  in  tint.  The  flask  is  removed 
from  the  flame,  and  a  very  little  powdered  permanganate  of  potassium  is 
added  till  the  green  colour  of  the  Hquid  shows  that  an  excess  of  permanganate 
has  been  added.  Should  the  Uquid  become  purple  and  not  green,  the  water 
has  not  been  all  driven  off.  After  cooling,  200  c.c.  of  ammonia-free  distilled 
water  are  added,  the  neck  of  the  flask  being  washed  free  from  acid  by  the 
process,  and  then  100  c.c.  of  a  solution  prepared  by  dissolving  200  grammes 
of  good  caustic  soda  in  1250  c.c.  of  distilled  water,  adding  2  grammes  of  per- 
manganate of  potassium  to  oxidise  organic  matter,  and  boihng  down  to  a 
litre.  After  the  addition  of  this  solution,  the  flask  is  immediately  connected 
with  the  condenser,  shaken,  and  the  distillation  slowly  commenced  till 
50  c.c.  have  distilled  over  and  been  condensed  in  very  dilute  hydrochloric 
acid,  after  which  the  liquid  in  the  flask  may  be  vigoroiTsly  boiled  until 
150  c.c.  or  175  c.c.  have  been  altogether  collected.  The  distillate  is  made 
up  to  250  c.c.  with  ammonia-free  water,  and  50  c.c.  of  this  are  nesslerised. 
It  may  be  necessary  to  dilute  still  further  before  nesslerising.  It  is  not  found 
that  with  the  extreme  dilution  of  natural  waters  the  determination  of  organic 
nitrogen  is  vitiated  by  the  presence  of  nitrates  and  nitrites. 

The  Albuminoid  Ammonia  Process. — This  process  was  devised  by  Mr. 
Wanklyn  and  the  late  Mr.  E.  T.  Chapman.  It  is  the  process  most  generally 
used  in  the  analysis  of  water  for  sanitary  purposes  ;  and  though  it  does  not 
determine  the  total  amount  of  organic  matter  or  nitrogenous  organic  impurity 
present,  it  affords  perhaps  as  accurate  a  comparative  estimate  of  the  organic 
contamination  of  a  water  as  any  other  chemical  method.  Eeagents 
required : — 


286  HYGIENE 

1.  Nessler's  reagent,  prepared  by  dissolving  35  grammes  of  ioclide  of 
potassium  and  13  grammes  of  mercmic  chloride  in  800  c.c.  of  boiling 
distilled  water,  and  then  adding  a  cold  saturated  solution  of  mercu.ric 
chloride  imtil  a  permanent  red  precipitate  begins  to  form  ;  l(iO  grammes  of 
sohd  caustic  potash  are  added,  and,  Avhen  dissolved,  the  whole  is  made  up 
■with  distilled  water  to  the  volume  of  a  litre.  A  httle  more  solution  of 
mercuric  chloride  is  then  added  to  make  the  solution  more  sensitive,  and  it 
is  then  allowed  to  settle.  It  should  have,  when  clear,  a  slight  yellow 
colour  ;  if  not,  it  is  less  sensitive,  and  requires  a  further  addition  of  mercuric 
chloride.  The  reagent  is  best  kept  in  a  large  carefully-stoppered  bottle,  and 
a  httle  of  the  solution  is  transferred  from  time  to  time  to  a  small  reagent 
bottle  as  required. 

2.  Ammonia. — 3*15  grammes  of  chloride  of  ammonium  are  dissolved  in  a 
litre  of  distilled  water,  and  from  this  a  weaker  solution  is  prepared  by  making 
up  10  c.c.  of  the  solution  to  a  litre  with  distilled  Avater.  Each  1  c.c.  of  the 
weaker  solution  =  t-o  o^^^  milligramme  NHg. 

8.  Alkalised  Permanganate  of  Potassium. — Eight  grammes  of  perman- 
ganate of  potassium  are  dissolved  in  a  htre  of  water  ;  200  grammes  of  stick 
potash  are  added,  and  the  whole  is  boiled  briskly  for  half  an  hour  or 
more,  tiU  about  one-fom*th  of  the  solution  is  evaporated.  The  solution  is 
then  made  up  to  a  litre  with  ammonia-free  distilled  water.  Or  the  above 
quantities  of  permanganate  and  caustic  potash  are  dissolved  in  1250  c.c.  of 
distilled  water  and  the  solution  boiled  down  rapidly  to  1000  c.c. 

4.  Ammonia-free  Water. — This  is  prepared  by  distilhng  good  tap-water, 
■\Aith  the  addition  of  a  httle  freshly  ignited  sodium  carbonate,  taking  care  to 
reject  the  first  portions  of  the  distillate,  and  not  to  distil  too  low.  Or,  as 
recommended  by  the  Society  of  Public  Analysts,  tlie  purest  distilled  water 
obtainable  to  which  one  jpart  per  1000  of  freshly  ignited  pure  sodium  car- 
bonate has  been  added  is  boiled  briskly  until  at  least  one-fourth  has  been 
evaporated ;  100  c.c.  of  this  water  must,  when  tested,  not  contain  so  much 
as  -5~J-7j-th  milligramme  of  NHg. 

The  apparatus  required  are,  a  stoppered  retort  holding  about  1200  c.c, 
fitted  to  a  Liebig's  condenser,  with  Bunsen's  burner  and  retort-clamp,  several 
glass  cyhnders  marked  at  50  c.c,  a  half-litre  measuring  flask,  a  50  c.c.  glass 
measm-e,  a  funnel  by  which  to  fill  the  retort,  a  pipette  to  dehver  2  c.c,  and 
a  graduated  stoppered  burette  or  pipette  graduated  to  ^^o^h  or  -^th  cubic 
centimetre.  The  appropriate  apparatus  can  be  readily  purchased  of  the 
instrument  makers  in  a  state  of  readiness  for  use.  A  sink  and  abundant 
supply  of  condensing  water  is  indispensable.  In  well-appointed  laboratories 
the  retort  is  kept  mounted  and  ready  for  use. 

The  operation  is  conducted  as  follows  :  After  having  cleaned  the  retort  by 
rinsing  it  with  strong  sulphuric  acid  and  then  with  water,  it  is  mounted,  and 
good  tap-water  is  distilled  from  it  tiU  the  distillate  comes  over  free  from 
ammonia  ;  and  the  retort  is  then  emptied  by  means  of  a  syphon.  Half  a 
litre  of  the  Avater  to  be  analysed  is  then  introduced  through  the  funnel, 
and  if  the  water  be  not  alkaline  about  half  a  gramme  of  freshly  ignited 
sodium  carbonate  is  added,  and  a  few  pieces  of  freshly  ignited  pumice. 
The  retort  is  then  heated  and  kept  boilmg  by  the  naked  flame  of  a 
Bunsen's  burner.  Successive  50  ccs.  of  distiUate  are  collected  in  the 
cyhnders  and  '  nesslerised '  in  the  manner  to  be  presently  described.  The 
distillation  is  stopped  when  no  more  ammonia  comes  over.  (Mr.  Wanklyn 
prefers  to  nesslerise  the  first  50  c.c,  Avhich  he  states  always  contains  three- 
fourths  of  the  whole  ammonia,  and  then  he  distils  a  further  150  c.c,  which 
he  rejects.)     The  ammonia  thus  obtained  is  termed  '  sahne  ammonia,'  or  by 


WATER  287 

some  '  free  ammonia.'     It  represents  the  ready-formed  ammonia,  or  its  salts, 
present  in  the  water.     50  c.c.  of  the  alkahsed  permanganate  of  potassimn 
are  now  introduced  into  the  retort  and  the  distillation  recommenced.    A  bold 
application  of  the  gas  flame  to  the  naked  retort  is  the  best  means  of  avoiding 
the  bumping  which  often  occurs,  especially  when  the  water  is  a  bad  one. 
Successive  50  c.cs.  of  distillate  are  collected  in  the  cylinders  and  nesslerised, 
and  the  distillation  is  continued  till  no  more  ammonia  is  evolved.     In  the 
case  of  peaty  waters  an  addition  of  ammonia-free  water,  and  repeated  distilla- 
tion, may  be  necessary.     When  the  distillation  is  completed  it  is  best  to  leave 
the  retort  unemptied,  and  when  a  fresh  analysis  has  to  be  made  the  retort  is 
washed  out  in  situ  with  tap-water  and  some  of  this  distilled  in  the  apparatus, 
which  is  thus  most  readily  rendered  free  from  ammonia.     The  ammonia 
liberated  by  the  alkalised  permanganate  is  termed  '  organic  ammonia '  or 
*  albuminoid  ammonia.'     It  is  the  measure  of  the  nitrogenous  organic  matter 
present  in  the  water,  which  is  broken  up  and  made  to  yield  ammonia  by  the 
alkalised  permanganate.      To  nesslerise  ammonia — saline  or  organic— to  a 
50  c.c.  cylinder  of  distillate,  2  c.c.  of  Nessler's  solution  are  added  by  means 
of  the  pipette,  and  the  mixture  stirred.     The  depth  of  yellow-brown  colour  is 
judged  of  by  the  eye,  and,  the  requisite  amount  of  ammonia  being  guessed,  a 
like  quantity  is  run  into  another  cylinder  from  the  burette  containing  the 
standard  ammonia  solution,  and  the  solution  diluted  till  it  measures  50 
CO.,  when  2  c.c.  of  Nessler's  solution  is  added.      The  two  cyhnders    are 
compared,  and  if  the  depth  of  tint  is  not  the  same,  another  cyhnder  is  pre- 
pared containing  less  or  more  ammonia,  as  the  case  may  be,  till  a  standard 
cylinder  and  the  cylinder  of  distillate  agree  in  tint.   With  a  practised  operator 
the  requisite  tint  is  speedily  obtained.     Should  the  Nessler's  solution  give 
a  precipitate  with  the    distillate,  it  is  requisite  to  repeat  the  distillation, 
and  take  smaller  quantities  of  the  distillate — 10  c.c.  or  20  c.c,  and  dilute  to 
50  c.c.  before  nesslerising.     Each  1  c.c.  of  standard  ammonia  solution  con- 
taining rhs^^  milligramme  of  NH3  will,  of  course,  represent  that  quantity 
in  the  500  c.c.  of  water  taken,  or  '02  part  per  million,  or   0-0014   grain 
per  gallon.      Thus,  e.g. — 500  c.c.  of  water  yielded  successive  distillates  of 
50  CO.,  which,  when  nesslerised,  gave  a  tint  equal  to  1*5  c.c,  0-5  c.c,  and  0*0 
■c.c  of  standard  ammonia,  and  of  albuminoid  ammonia  equal  to  3  c.c,  2  c.c, 
1  c.c,  0-5  c.c,  and  0-0  c.c.  standard  ammonia  solution.     Then  we  have : — 

Saline,  NH^. — 1-5  -|--5  =  2  x  2=4  —  100th  milhgramme  per  litre  NH3, 
or  '04  part  per  million ;  and  -04  x  '07  =  '0028  grain  per  gallon. 

Albuminoid,  NH^.—S  +  2  +  1  +  0-5  =  6-5  x  2  =  13  -  100th  milh- 
gramme per  litre,  or  0-13  per  million  ;  and  -13  x  "07  =  "0091  grain  per  gallon. 

The  advantages  of  the  albuminoid  ammonia  process  are,  the  rapidity  with 
which  it  is  carried  out,  the  simplicity  of  the  apparatus  required,  and,  what  its 
defenders  assert,  the  greater  certainty  of  its  results  when  compared  with 
those  obtained  by  any  other  process.  It  is  not  j)retended  that  the  nitrogen 
yielded  in  the  form  of  albuminoid  ammonia  is  all  that  contained  in  the 
water  operated  on  ;  Mr.  Wanklyn,  indeed,  asserts  that  the  nitrogen  obtained 
is  a  definite  fraction  of  that  contained  in  many  organic  bodies,  but  even  this 
can  scarcely  be  asserted  of  the  unknown  forms  of  nitrogenous  organic  matter 
contained  in  waters.  Its  detractors  aver,  on  the  other  hand,  that  the 
albuminoid  ammonia  yielded  is  uncertain  in  its  amount,  and  is  no  definite 
guide  to  the  organic  nitrogen  present  in  a  water  ;  and  that  it  is  misleading. 
Probably  the  truth  is,  that  neither  is  the  albuminoid  ammonia  a  certain 
index  to  the  quality  of  a  water,  nor  an  altogether  unreliable  one.  Generally, 
it  is  fairly  reliable,  and  no  more  can  be  asserted  with  assuredness  of  any 
other  process  for  determining  the  pollution  of  a  water. 


288  HYGIENE 

The  behaviour  of  peaty  waters  when  submitted  to  the  albuminoid 
ammonia  process  is  pecuhar.  They  yield  a  relatively  large  quantity  of 
albuminoid  ammonia,  which  is  evolved  slowly  and  somewhat  persistently. 
This  peculiarity  is  so  well  known  that  it  can  scarcely  mislead  any  skilled 
analyst  accustomed  to  use  the  process.  Badly  polluted  waters,  on  the  other 
hand,  generally  yielded  their  high  proportion  of  albuminoid  ammonia 
promptly  and  sharply. 

The  Permanganate  Process  for  Determination  of  Oxygen  required  to 
Oxidise  Organic  Matter. — This  process  is  carried  out  in  various  ways.  The 
following  is  the  method  as  advised  by  Dr.  Tidy,  who  has  specially  investigated 
the  process  ('  Jour,  of  Chem.  Soc.  Trans.,'  vol.  xxxv.,  1879,  p.  46). 

The  following  solutions  are  required  (for  the  quantities  given  by  Dr. 
Tidy  in  grains  and  septems  are  substituted  grammes  and  cubic  centimetres)  : 

1.  Dilute  sulphuric  acid  :  1  part  of  pure  sulphuric  acid  with  3  parts  of 
distilled  water. 

2.  Solution  of  permanganate  of  potassium  :  0'28G  gramme  per  litre ; 
10  c.c.  =  '714  milligramme  of  available  oxygen. 

3.  Solution  of  iodide  of  potassium,  free  from  iodate  :  1  part  in  10  parts 
of  water. 

4.  Thiosulphate  of  sodium  (hyposulphite)  :  0*77  gramme  in  a  litre  of 
distilled  water. 

5.  Starch  solution,  carefully  prepared :  about  1^  gramme  in  100  c.c.  of 
water. 

Two  similar  pint-glass  flasks  are  very  carefully  cleaned,  and  in  each  is 
placed  250  c.c.  of  the  water  to  be  analysed,  10  c.c.  of  dilute  sulphuric  acid, 
and  10  c.c.  of  the  permanganate  solution,  noting  the  time  of  adding  the  per- 
manganate. If  before  the  end  of  three  hours  the  colour  of  the  permanganate 
has  disappeared,  a  second  or  even  a  third  addition  of  10  c.c.  of  perman- 
ganate must  be  made,  so  as  to  maintain  the  red  colour  of  the  liquid  in  the 
flask.  At  the  same  time  as  the  above  experiments  are  made,  two  similar 
quantities  of  distilled  water  are  treated  in  a  precisely  similar  manner.  At 
the  end  of  one  hour,  and  at  the  end  of  three  hours,  one  of  each  of  the  flasks 
containing  distilled  water  and  the  water  under  examination  respectively 
is  treated  with  two  drops  of  the  iodide  of  potassium  solution,  and  then 
titrated  with  the  thiosulphate  solution.  The  other  two  flasks — one  of  dis- 
tilled water,  and  the  other  of  the  sample  water — are  allowed  to  remain  till 
the  reaction  with  the  permanganate  has  gone  on  for  three  hours,  and 
then  two  drops  of  the  iodide  solution  are  added,  and  the  titration  with  thio- 
sulphate ('  hypo ')  completed. 

The  value  of  the  thiosulphate  solution  must  be  very  frequently  deter- 
mined, as  the  salt  decomposes  in  solution.  A  blank  experiment  with 
distilled  water  is  made  by  putting  250  c.c.  of  distilled  water  iato  a  flask,  with 
10  c.c.  of  dilute  sulphuric  acid  and  10  c.c.  of  the  permanganate  solution. 
Two  drops  of  the  iodide  of  potassium  solution  are  added,  and  then  the 
thiosulphate  solution  is  run  in  from  a  burette  until  the  yellow  colour  of  free 
iodine  has  nearly  disappeared.  A  few  drops  of  the  starch  solution  are  now 
added,  and  the  addition  of  thiosulphate  continued  till  the  blue  colour  just 
disappears  ;  and  the  amount  of  the  thiosulphate  used  is  noted.  In  operating 
upon  the  water  under  analysis,  the  same  process  of  titrating  with  thiosulphate 
is  followed  after  one  and  three  hours'  action  of  the  permanganate. 

The  calculation  of  the  results  is  as  follows  : 

Let  X  =  no.  of  c.cs.  of  thiosulphate  used  hi  the  distilled  water. 

Y  =  no.  of  c.cs.  of  thiosulphate  used  in  the  water  under  examination. 

Then  if  10  c.c.  of  the  permanganate  solution  were  used, 


WATER  289 

X  —  Y  X  0-2  _  gj,g^-j^g  Qf  oxygen  required  to  oxidise  organic  matter  in  one 

A. 
gallon  of  the  water. 

If  20  c.c.  of  permanganate  were  used,  2X  must  be  substituted  for  X  in 
the  above  equation  ;  if  30  c.c.  substitute  3X,  and  so  on,  in  making  the 
calculation. 

The  method  recommended  by  the  Society  of  Public  Analysts  ('The 
Analyst,'  vol.  vi.,  1881,  p.  126)  of  carrying  out  the  operation  is  somewhat 
different,  and  is  performed  thus  : —  ^ 

Two  separate  determinations  are  made— the  amount  oi  oxygen  absorbed 
during  fifteen  minutes,  and  that  absorbed  during  four  hours  ;  both  being 
made  at  a  temperature  of  80°  F.  (26° -7  C).  These  are  made  in  12  oz. 
stoppered  bottles.  Put  250  c.c.  of  the  water  into  each  of  two  of  the  bottles  ; 
stopper  and  immerse  in  a  water-bath  until  the  temperature  reaches  SO'-'  F.  Now 
add  to  the  water  10  c.c.  of  dilute  sulphuric  acid  (1-3),  and  10  c.c.  of  a  solution 
of  permanganate  of  potassium  (0-395  gramme  per  htre).  Fifteen  minutes  after 
the  addition  of  the  permanganate,  one  of  the  bottles  is  removed  from  the 
bath,  2  or  3  drops  of  a  solution  of  iodide  of  potassium.  (1  in  10)  added,  and 
the  liberated  iodine  titrated  by  means  of  a  solution  of  thiosulphate  (1  gramme 
in  1  litre  of  water),  the  end  of  the  reaction  being  determined  by  a  solution  of 
starch  (1  in  600),  as  in  Dr.  Tidy's  process.  At  the  end  of  four  hours  the 
other  bottle  of  water  is  titrated  in  the  same  manner.  But  if  before  the 
expiration  of  four  hours  the  pink  colour  of  the  solution  should  grow  very 
pale,  a  further  addition  of  a  measured  quantity  of  the  permanganate  solution 
must  be  made,  so  as  to  keep  up  a  decided  pink  or  red  colour.  The  thio- 
sulphate solution  must  be  titrated  with  250  c.c.  of  good  distilled  water  from 
time  to  time,  into  which  is  placed  10  c.c.  of  the  permanganate  solution,  and 
then  a  few  drops  of  the  iodide  of  potassium  solution.  The  quantity  used 
will  represent  the  quantity  of  thiosulphate  solution  equivalent  to  0*00395 
gramme  permanganate,  or  -001  of  available  oxygen.  The  calculation  is 
this. 

Let  a  =  number  of  c.cs.  thiosulphate  required  in  blank  experiment  to  =  10 
c.c.  permanganate. 
b  =  number  of  c  c.  thiosulphate  used  in  titration  of  the  watei. 

~     7,      y      .OQ 

Then  - — - -  =  grains  of  oxygen  per  gallon  required  to  oxidise  organic 

a 
matter. 

Recently  Mr.  Blair  has  proposed  a  novel  method  of  estimating  the  amount 
of  organic  matter  in  drinking  water ;  but  his  process  has  not  as  yet  been 
much  adopted  ('  The  Organic  Analysis  of  Potable  Waters,'  by  J.  A.  Blair, 
M.B.,  1890). 

Lead  and  Copper. — An  examination  for  these  injurious  metals  may  be 
readily  and  expeditiously  made  ;  and  if  one  of  these  metals  only  be  present, 
as  is  usually  the  case,  by  calorimetric  methods. 

100  c.c.  of  the  water  is  placed  in  a  nesslerising  cylinder,  and  a  drop  of 
solution  of  sulphide  of  ammonium  is  stirred  in,  when  a  dark  colouration  or 
precipitate  will  indicate  the  presence  of  iron,  lead,  or  copper.  If  it  be  due 
to  iron,  the  colour  will  be  discharged  by  the  subsequent  addition  of  a  drop 
or  two  of  strong  hydrochloric  acid,  which  will  not,  however,  discharge  the 
colour  if  lead  or  copper  be  present. 

Copper  may  be  distinguished  from  lead  by  placing  100  c.c.  of  the  water 

in  a  similar  cylinder,  acidifying  with  a  drop  or  two  of  acetic  acid  and  a  drop 

of  a  solution  of  ferrocyanide  of  potassium,  when,  if  copper  be  present,  the 

liquid  will  acquire  a  faint  red  tint.     By  comparing  the  depth  of  tint  with 

VOL.  I.  u 


-290  HYGIENE 

distilled  water  similarly  treated,  and  to  -wliich  a  standard  solution  of  sulphate 
of  copper  has  been  added,  the  quantity  of  copper  may  be  estimated.  A 
convenient  solution  for  this  purpose  is  an  aqueous  solution  of  crystallised 
sulphate  of  copper,  5-6  grammes  to  the  Utre  :  1  c.c.  of  this  solution  contains 
1-43  milhgramme  of  copper ;  and  hence,  working  with  100  c.c.  of  water, 
each  O'l  c.c.  copper  solution  added  to  the  water  corresponds  to  0*1  grain 
copper  per  gallon. 

The  presence  of  lead  may  be  confirmed  by  placing  some  of  the  water  in  a 
tall  glass  cylinder  and  sprinkling  on  its  surface  a  few  fragments  of  powdered 
potassium  bichromate,  when,  if  lead  be  present,  a  cloud  of  yellow  lead  chro- 
mate  will  fall  in  streaks  to  the  bottom  of  the  cylinder.  The  quantity  of 
lead  may  be  determined  by  treating  100  c.c.  of  the  water  in  a  cylinder  as 
in  the  titration  of  copper,  adding  a  drop  of  hydrochloric  acid  and  2  c.c.  of 
good  sulphuretted  hydrogen  water.  The  depth  of  brown  or  black  colour 
produced  is  then  compared  with  that  produced  by  the  same  quantity  of  the 
same  reagents,  added  to  100  c.c.  distilled  water  in  a  similar  cylinder.  The 
standard  lead  solution  employed  should  contain  2-62  grammes  crystallised 
lead  acetate,  and  a  few  drops  of  acetic  acid  in  a  litre  of  distilled  water. 
Each  1  c.c.  contains  1"43  milhgramme  of  lead ;  and  when  100  c.c.  of  water 
are  operated  on,  each  O'l  c.c.  corresponds  to  0*1  grain  of  lead  per  gallon. 

Hardness. — For  hygienic  purposes  it  is  always  desirable  to  estimate  the 
hardness  of  a  water,  i.e.  its  soap-destroying  capacity ;  and  although  it  is 
undoubted  that  the  hardness  of  a  water,  as  determined  by  experiment,  is  not 
always  a  safe  guide  to  the  quantity  of  lime  and  magnesia  salts  present — ■ 
these  being  the  chief  soap-destroying  constituents  of  ordinary  waters — an 
estimate  of  the  so-called  hardness  of  a  water  by  Clark's  soap  test  ought 
never  to  be  omitted. 

A  hard  water  is  one  which  requires  much  soap  in  order  to  yield  a 
permanent  lather,  and  is  usually  rich  in  lime  and  magnesia  salts  ;  a  soft 
water  is,  conversely,  one  usually  poor  in  the  salts  of  the  alkaline  earths,  and 
readily  yields  a  lather  with  a  small  quantity  of  soap.  Again,  the  hardness 
of  a  water  is  distinguished  as  total  hardness  or  the  hardness  of  the  natural 
water ;  ^jer7?za«eTOi  hardness,  or  that  which  remains  after  boiling,  and 
chiefly  due  to  the  presence  of  those  salts  of  calcium  and  magnesium — 
such  as  the  sulphates,  chlorides,  and  nitrates — which  are  not  thrown  down 
on  boiling ;  and  temporary  hardness,  obtained  by  subtracting  the  perma- 
nent from  the  total  hardness,  and  attributable  to  the  carbonates  of  calcium 
and  magnesium  present.  These  definitions  are,  nevertheless,  not  strictly 
accurate  ;  for  hardness  may  be  due  to  the  presence  of  ferruginous  salts,  and 
permanent  hardness  may  be  due,  in  the  absence  of  temporary  hardness,  to 
the  existence  of  free  mineral  or  vegetable  acids  in  the  water  ;  for  acids  destroy 
soap  equally  with  lime  compounds.  It  is  hence  best  to  consider  hardness 
strictly  and  solely  as  soap-destroying  power,  to  whatever  cause  this  be  assign- 
able. 

Dr.  Clark,  of  Aberdeen,  first  proposed  a  method  of  determining  hardness 
experimentally,  in  substitution  of  the  method  of  computing  the  hardness 
from  the  amounts  of  lime  and  magnesia  found  by  analysis,  and  his  method, 
or  a  modification  of  it,  is  now  universally  adopted  ('  On  the  Examination 
of  Water  for  Towns  for  its  Hardness,'  by  G.  T.  Clark,  1847). 

"When  a  solution  of  soap — best  in  dilute  alcohol — is  added  to  distilled 
water,  and  the  whole  is  agitated,  a  faint  opalescence  appears,  and  at  first  no 
lather  forms  ;  but  the  addition  of  a  very  small  further  quantity  of  the  soap 
solution  results  in  the  formation  of  a  permanent  lather  on  agitation.  But  if 
an  ordinary  hard  water  be  treated  in  the  same  manner,   the   opalescence 


WATEB  291 

iDecomcs  a  marked  turbidity  or  distinct  precipitate,  and  much  more  soap 
solution  has  to  be  added  to  procure  a  permanent  lather,  which  appearance 
indicates  the  presence  of  a  slight  excess  of  soap — conferring  viscosity  to  the 
liquid — beyond  the  amount  necessary  to  decompose  the  lime  and  magnesia 
salts,  and  other  soap-destroying  compounds  present ;  nor  does  the  test 
directly  distinguish  between  one  soap-destroying  compound  and  another. 

It  is  customary  to  express  the  hardness  in  '  degrees  ;  '  and  each  degree 
of  Clark's  scale  indicates  one  grain  of  calcium  carbonate  per  gallon  of  water, 
or  the  equivalent  of  one  grain  of  chalk  in  soap -destroying  power.  Thus, 
e.g.,  one  degree  of  hardness  may  be  due  to  one  grain  of  calcium  carbonate, 
I'll  grain  of  calcium  chloride,  or  1*36  grain  of  calcium  sulphate,  &c., 
each  of  these  calcium  compounds  containing  in  the  above  quantities  re- 
spectively 0*4  grain  of  calcium.  In  France  each  degree  of  hardness  indi- 
cates one  part  by  weight  of  calcium  carbonate,  or  its  equivalent,  per 
100,000  parts  of  water;  whilst  in  Germany  a  degree  of  hardness  indicates 
one  part  of  lime  (CaO),  or  its  equivalent,  per  100,000  parts  of  water.  Hence 
ihe  various  values  of  degrees  of  hardness  are  : — English  1°  =  German  0°"8  = 
French  1°*4  nearly.  Many  analysts  who  give  the  results  of  their  analyses  in 
parts  per  100,000  use  the  French  scale  of  hardness. 

The  requisites  for  the  determination  of  hardness  : — 

1.  A  standard  solution  of  calcium  sulphate  is  obtained  by  grinding  in 
a  mortar  0-1965  gramme  of  crystallised  selenite,  CaS04  2H2O,  with  a 
sufficiency  of  distilled  water  to  dissolve  it,  and  making  up  to  the  volume  of  a 
litre.  Or  0"2985  gramme  barium  nitrate  may  be  dissolved  in  distilled 
water  and  made  up  to  a  litre.  Either  of  these  solutions  contains  the 
equivalent,  in  calcium  or  barium  salts,  of  8  grains  calcium  carbonate  per 
gallon. 

2.  A  stoppered  narrow-mouthed  bottle  holding  200  c.c,  or,  as  preferred 
by  some,  one  holding  100  c.c. 

3.  A  burette  on  stand  divided  into  cubic  centimetres  and  tenths  of  a 
cubic  centimetre. 

4.  The  standard  soap  solution.  A  potash  soap  is  best  for  the  desired 
purpose,  prepared  thus  :  15  parts  of  the  lead  plaster  of  the  British  Pharma- 
copoeia (lead  oleate)  are  warmed  on  a  water-bath  with  4  parts  of  potassium 
carbonate  and  rubbed  in  a  mortar  to  a  uniform  consistence  ;  then  digested 
with  ordinary  rectified  methylated  spirit,  allowed  to  deposit,  and  diluted  with 
^ater  in  the  proportion  of  three  volumes  of  water  to  every  five  volumes  of 
rectified  spirit  employed ;  in  other  words,  the  alcohol  is  reduced  to  about 
proof  strength,  and  any  subsequent  dilution  is  made  with  spirit  of  proof 
strength.     The  solution  is  then  filtered. 

Very  commonly  the  soap  solution  is  prepared  by  dissolving  ordinary  good 
undried  Castile  soap  in  the  proportion  of  14  grammes  to  the  litre  of  a  mixture 
of  methylated  rectified  spirit  and  distilled  water  in  equal  volumes ;  and  there 
is  no  objection  to  this  when  no  minute  degree  of  accuracy  is  demanded.  In 
any  case  it  is  well  to  prepare  a  stock  bottle  of  strong  soap  solution,  and  to 
dilute  some  of  the  clear  liquid  from  time  to  time  with  alcohol  of  proof  strength 
and  standardise  it  in  the  following  manner  occasionally,  as  soap  solutions  are 
apt  to  deposit  in  winter,  or  when  long  kept,  and  thus  to  lose  strength. 

The  standardising  of  the  soap  solution  is  effected  by  taking  50  c.c.  of 
the  standard  calcium  (or  barium)  solution,  placing  it  in  the  bottle  and 
running  in  the  soap  solution  from  a  burette  till  a  thick  fine  uniform  white 
froth  is  produced  on  vigorously  shaking  the  bottle,  and  should  remain  for  five 
minutes  when  the  bottle  is  placed  on  its  side.  If  less  than  9  c.c.  of  the  soap 
solution  are  required,  the  requisite  quantity  of  dilute  alcohol  is  added  to  reduce 

u2 


292  HYGIENE 

it  to  the  required  strength,  i.e.  so  that  9  c.c.  of  the  soap  is  exactly  sufl6cienfc 
to  give  a  permanent  lather  -with  50  c.c.  of  the  standard  calcium  solution 
of  8*0°  of  hardness.  For  example,  50  c.c.  of  the  standard  calcium  gave  a 
lather  persisting  for  five  minutes  with  G  c.c.  of  a  soap  solution ;  then  each 
litre  of  this  soap  solution  must  be  diluted  till  it  measures  |?ths  of  a  litre,  or 
1500  c.c.  The  solution  after  this  adjustment  must  be  again  titrated,  and  if 
50  c.c.  of  the  standard  water  requires  more  or  less  than  the  requisite  9  c.c, 
a  little  more  dilute  alcohol,  or  a  little  strong  solution  of  soap  must  be  added 
till  the  requisite  strength  is  obtained. 

The  estimation  of  hardness  is  effected  by  pipetting  50  c.c.  of  the  water 
into  the  stoppered  bottle,  and  running  in  the  standard  soap  solution  fi'om 
the  burette,  at  first  rapidly,  and  then  very  slowly,  with  repeated  shaking  till 
a  fine  uniform  creamy  lather  is  obtained,  which  persists  for  five  minutes, 
■when  the  bottle  is  allowed  to  rest  on  its  side.  An  approximation  to  the 
quantity  of  soap  required  being  thus  obtained,  the  titration  is  repeated  with 
greater  care,  adding  the  soap  at  first  in  quantities  of  1  c.c.  at  a  time,  and 
towards  the  end  of  the  reaction  drop  by  drop  till  the  desired  lather  is 
obtained.  The  carbonic  acid  liberated  on  agitation  should  from  time  to  time 
be  removed  by  blowing  air  into  the  bottle  by  a  pair  of  bellows. 

Should  more  than  9  c.c.  of  soap  be  required,  it  is  always  well — and  m 
the  case  of  magnesian  waters  indispensable — to  dilute  the  water  under 
examination  with  its  own  bulk,  twice  its  own  bulk,  &c.,  of  distilled  water  till 
not  more  than  9  c.c.  is  requirod  by  50  c.c.  of  the  diluted  water. 

The  proportion  between  the  soap  used  and  the  actual  degree  of  hardness 
of  a  water  is  not  constant,  and,  according  to  the  accurate  observations  of 
Faiszt  and  Knausz,  the  degree  of  hardness  corresponding  to  each  1  c.c.  of 
soap  solution  used  mcreases  constantly  with  the  amount  of  soap  used. 
According  to  Wanklyn,  distilled  water  requires  1  c.c.  of  soap  solution  to 
produce  a  lather  ;  and  he  deducts  1  c.c.  from  the  number  of  cubic  centi- 
metres of  soap  solution,  and  the  remainder  gives  the  hardness  in  degrees. 
The  later  experiments  of  Clark,  confirmed  by  those  of  Faiszt  and  Knausz, 
give  0*5  c.c.  approximately,  as  the  amount  of  soap  required  by  50  c.c.  of 
distilled  water.  The  follo"ttang  table  expresses  Clark's  latest  results,  and  is 
sufficiently  accurate : 

c.c.  of  soap  Degrees  of 

solution  used.  hardness  (Clark). 

0-45 0° 

1-45 1° 

2-70 2° 

3-85 3° 

4-95 4° 

6-00 5° 

After  which  deduct  1  c.c.  from  the  number  of  c.cs.  used,  and  the  re- 
mainder is  the  hardness  in  degrees. 

In  this  way,  the  total  hardness  having  been  determined,  250  c.c.  of  the 
water  is  kept  boiling  over  a  naked  flame  for  half  an  hour  or  an  hour,  the 
evaporated  water  being  nearly  replaced  from  time  to  time  by  distilled  water. 
The  water  is  quickly  filtered  into  a  dry  250  c.c.  flask,  the  filter  quickly  washed 
with  boiling  distilled  water,  and  the  whole  adjusted  to  250  c.cs.  when  cold. 
60  c.c.  of  the  boiled  water  is  then  titrated  anew  with  soap  solution,  and  in 
this  way  the  permanent  hardness  is  obtained.  The  difference  between  total 
and  permanent  gives  the  teviporary  hardness. 

It  must  not  be  forgotten  that  if  the  water  be  diluted  the  necessary  cor- 
rection for  dilution  must  be  made. 


WATEB  293 

The  following  are  useful  data  as  to  hardness : 

1  degree  (1°)  Clark's  scale  =  1-4  degree  (l°-4)  on  the  centesimal  scale 

(parts  per  100,000). 
1  degree  (1°)  Clark's  scale  =  0-8  degree  (0°-8)  on  the  German  scale. 
1  grain  CaCOg  =  I'll  gr.  CaClg  =  1-38  gr.  CaS04  =  0-56  gr.  CaO 

=  0-84  gr.  Mg  CO3  =  0-4  gr.  Mg  0  in  soap-destroying  power. 
1  grain  per  gallon  CaCOg  =  1-43  milligramme  per  litre. 
Distilled  water  requires  approximately  as  much  soap  to  yield  a  lather  as 
0-7  grain  per  gallon  CaCOg,  or  1  part  CaCOg  in  100,000  parts  of  water. 
This  is  the  excess  of  soap  beyond  that  required  to  precipitate  the  calcareous 
salts  of  the  water  required  to  produce  a  lather  on  agitation  of  the  water  with 
the  soap. 

Iron. — It  is  not  often  necessary  for  sanitary  purposes  to  determine  the 
quantity  of  iron  present  in  a  drinking  water.  Generally  it  is  sufficient  to 
ascertain  that  a  water  is  not  chalybeate  by  the  sense  of  taste,  and  by  ascer- 
taining that  it  does  not  assume  a  purple  or  inky  hue  on  the  addition  of 
a  few  drops  of  tincture  of  galls  to  half  a  pint  of  the  sample.  But  when  it 
is  desired  to  ascertain  the  amount  of  iron  present,  this  can  be  most  con- 
veniently done  by  making  use  of  a  process  devised  by  Carnelley  ('  Mem.  Man- 
chester Lit.  and  Phil.  Soc'  1874-5,  p.  346).  1  c.c.  of  dilute  sulphuric  acid  is 
added  to  a  measured  volume  of  the  water,  to  which  a  dilute  solution  of  per- 
manganate of  potassium  is  added  until  a  permanent  pink  tint  is  imparted  to 
the  liquid ;  and  the  volume  is  then  made  up  to  a  litre  by  the  addition  of 
distilled  water.  The  quantity  of  the  water  under  examination  requisite  to 
make  up  the  litre  is  judged  of  approximately  by  previous  quahtative  tests  for 
iron.  50  or  100  c.c.  of  the  Htre  of  hquid  thus  obtained  are  placed  in  a 
cylinder,  5  c.c.  of  dilute  nitric  acid  are  added,  and  then  a  couple  of  drops 
of  a  solution  of  potassium  ferrocyanide.  The  depth  of  blue  colour  (Prussian 
blue)  produced  is. then  compared  with  that  produced  under  like  conditions 
in  a  similar  cylinder  by  a  standard  solution  of  iron  when  mixed  with  the 
same  quantities  of  the  dilute  nitric  acid  and  ferrocyanide  solutions.  The 
iron  (ferric  salt)  solution  is  prepared  by  dissolving  0-7  gramme  of  pure 
crystallised  ferrous  ammonium  sulphate  in  water,  acidulating  with  1  c.c.  of 
dilute  sulphuric  acid,  oxidising  by  the  addition  of  a  solution  of  potassium 
permanganate  till  a  barely  visible  permanent  rose  tint  is  produced,  and 
diluting  with  distilled  water  to  a  litre.  1  c.c.  of  this  solution  =  0-1  milli- 
gramme of  iron. 

For  example  :  600  c.c.  of  a  water  was  oxidised  with  permanganate  and 
made  up  to  1  litre.  Of  this  50  c.c.  gave  as  much  blue  colour  with  ferro- 
cyanide as  0*5  c.c.  of  the  standard  iron  solution  in  50  c.c.  of  distilled  water. 
Then  O'S  x  O'l  x  20  =  1  milligramme  is  the  quantity  of  iron  in  500  c.c.  of 
the  water  under  examination  ;  and  1  x  '2  =  0-2  is  the  iron  per  100,000 
parts  ;  and  1  x  0-14  =  0-14  is  the  grains  of  iron  per  gallon. 

In  operating  upon  chalybeate  waters  greater  dilution  is  necessary  ;  but 
the  results  are  sufficiently  accurate  for  all  ordinary  purposes. 

Silica. — A  litre  of  the  water  is  acidified  with  hydrochloric  acid,  and  eva- 
porated to  dryness  in  a  platinum  dish,  the  residue  digested  with  strong 
hydrochloric  acid  in  a  warm  place,  water  added  to  the  separated  silica,  which 
is  filtered  off,  well  washed,  dried,  ignited,  and  weighed. 

Manganese. — This  metal  is  rarely  present  in  waters  in  apj)reciable  quan- 
tity, though  its  presence  was  formerly  not  at  all  uncommon  in  the  acid  waters 
contaminated  by  the  discharge  from  bleach-works.  Manganese  may  be  de- 
tected by  concentrating  the  water,  precipitating  with  ammonia  and  a  few  drops 


294  HYGIENE 

of  a  solution  of  peroxide  of  hydrogen,  and  collecting  the  precipitate  of  ferric^ 
aluminic,  and  manganic  oxides  on  a  filter.  The  washed  and  dried  precipitate 
■with  the  filter  is  fused  with  caustic  soda  and  a  fragment  of  potassium 
nitrate  in  a  silver  dish,  when  the  manganese  is  converted  into  a  manga- 
nate.  On  treating  the  residue  with  water  faintly  acidulated  with  sulphuric 
acid,  a  rose-red  or  purple  solution  of  permanganic  acid  is  obtained,  which 
when  examined  by  the  spectroscope  exhibits  fine  dark  characteristic  absorp- 
tion bands,  and  is  decolourised  by  the  addition  of  a  drop  or  two  of  ammonium 
oxalate  solution. 

A  quantitative  determination  of  the  manganese  is  seldom  or  never  re- 
quired in  the  hygienic  analysis  of  a  water. 

Chromium. — Compounds  of  chromium  (chromic  salts  and  chromates)  may 
be  detected  by  evaporating  a  litre  or  two  of  the  water  to  dryness,  and  fusing 
the  dry  residue  wath  sodium  carbonate  and  a  fragment  of  potassium  nitrate 
in  a  silver  dish.  The  residue  is  extracted  with  water,  filtered,  and  the. 
filtrate  neutralised  with  nitric  acid  and  evaporated  twice  to  dryness  in  a  por- 
celain dish,  in  order  to  get  rid  of  free  nitric  acid.  The  neutral  residue  dis- 
solved in  water  will,  if  chromium  be  present,  yield  a  yellow  precipitate 
insoluble  in  acetic  acid  when  solution  of  lead  acetate  is  added,  and  will  also 
yield  a  red  precipitate  of  silver  chromate  if  excess  of  silver  nitrate  solution 
be  added. 

A  water  containing  chromium  compounds  should  be  unhesitatingly  re- 
jected as  a  drinking-water,  these  compounds  being  highly  irritant  and  toxic, 
even  in  minute  quantities. 

Dissolved  Oxygen. — Dr.  Thresh  ('  Proc.  Chem.  Soc'  1890,  p.  1)  has  devised 
the  simplest  method  of  estimating  the  dissolved  oxygen  gas  in  water. 

The  solutions  required  for  the  process  are  :  (1)  a  solution  containing 
0*5  gramme  sodium  nitrite  and  20  grammes  potassium  iodide  in  100  c.c, 
distilled  water ;  (2)  an  aqueous  solution  containing  7*75  grammes  sodium 
thiosulphate  (hyposulphite)  to  the  litre.  1  c.c.  of  this  corresponds  to  0*25 
milligramme  of  oxygen ;  (3)  clear  starch  solution ;  (4)  dilute  sulphuric 
acid  (1 :  3).  The  apparatus  used  consists  of  a  wide-mouthed  bottle  of 
500  c.c.  capacity,  provided  with  a  caoutchouc  stopper  through  which  four 
holes  are  bored.  Through  one  passes  the  neck  of  a  cylindrical '  separator  ' 
funnel  of  known  capacity,  and  through  the  second  a  tube  drawn  out  to  a  fine 
point,  which  is  connected  by  a  short  length  of  flexible  tubing  with  the 
thiosulphate  burette,  while  inlet  and  exit  tubes  for  coal-gas  are  passed 
through  the  third  and  fourth  holes,  the  exit  tube  having  attached  to  it  a 
sufficient  length  of  caoutchouc  tubing  to  permit  of  connection  being  esta- 
bhshed  between  the  bottle  and  the  separator  when  the  stopper  of  the  latter 
is  withdrawn. 

The  separator  is  filled  with  the  water  to  be  examined,  and  1  c.c.  of  the 
nitrite-iodide,  and  1  c.c.  of  the  acid  solution  are  added.  If  the  pipette  be 
held  vertically,  with  its  end  just  below  the  surface  of  the  water,  the  solutions 
flow  in  a  sharply  defined  column  to  the  lower  part  of  the  separator  ;  so  that 
a  very  small  quantity,  if  any,  is  lost  in  the  water  which  overflows  when  the 
stopper  is  inserted.  The  apparatus  is  inverted  several  times,  and  then  a 
quick  current  of  coal-gas  is  passed  through  the  bottle,  the  escaping  gas  being, 
ignited.  After  fifteen  minutes  the  flame  is  extinguished  ;  a  cork  is  attached 
in  place  of  the  jet,  and  is  inserted  in  place  of  the  stopper  of  the  separator ; 
and  the  w^ater  is  then  allowed  to  flow  into  the  bottle.  The  exit  tube  having 
been  disconnected  from  the  funnel  and  the  gas  lighted,  thiosulphate  is  run 
in  imtil  the  colour  of  the  iodine  is  nearly  destroyed  ;  about  1  c.c.  of  starch 
solution  is  then  added  from  the  separator,  and  the  titration  is  completed.. 


WATER  295 

The  effect  of  the  nitrite,  dilute  acid,  and  starch  solutions  is  determined  by 
removing  the  separator  and  adding  5  c.c.  of  each  in  succession  and  then 
titrating.  An  allowance  is  made  for  the  oxygen  dissolved  in  it,  on  the 
assumption  that  as  much  oxygen  is  dissolved  in  it  as  in  distilled  water  at  the 
same  temperature.  At  the  temperature  of  59°  F.  (15"  G.)  distilled  water 
dissolves  7  milligrammes  of  oxygen  per  litre. 


DETEEMINATION   OP   THE   ACTION   OF   A  WATER   UPON   LEAD 

This  important  determination,  where  the  adoption  of  a  new  water-supply 
is  under  consideration,  is  one  beset  with  difficulties ;  and  the  results  ob- 
tained are,  as  a  rule,  by  no  means  satisfactory  or  conclusive. 

A  method  commonly  adopted  is  to  immerse  fresh-scraped  clean  plates  of 
lead,  6x2  inches  in  size,  in  a  known  volume,  say  500  c.c.  (or,  better,  1  pint 
=  568  c.c.)  of  the  water  in  a  loosely  stoppered  bottle  capable  of  holding 
double  this  quantity  of  liquid.  After  twenty-four  hours  the  strips  of  lead  are 
removed  and  any  corrosion  or  deposit  is  noted.  After  filtration  the  water  is 
examined  for  the  lead  in  the  usual  manner  (see  p.  256). 

A  better  and  more  satisfactory  plan  is  to  take  a  36-inch  length  of  fresh 
well-cleaned  lead  pipe,  of  ^  inch  bore,  closed  by  means  of  a  cork  provided 
with  a  pinch-cock  below,  and  by  a  cork  above.  The  tube  is  rinsed  with  the 
water  and  then  filled  with  it,  corked,  and  placed  in  an  early  horizontal  posi- 
tion, the  pinch-cock  being  at  the  lowest  end  of  the  tube.  After  a  definite 
period,  say  12,  18,  or  24  hours,  the  water  is  run  out  of  the  tube,  and  replaced 
by  a  fresh  quantity,  which  is  again  withdrawn  at  the  end  of  any  desired  period. 
The  successive  quantities  of  water  are  measured,  and  the  lead  present  deter- 
mined as  before.  In  this  way  the  action  of  the  water  upon  lead  (either  fresh 
pipe  or  after  some  use)  may  be  determined.  The  volume  of  water  held 
by  a  pipe  of  ^  inch  bore,  and  36  inches  in  length,  is  one-fifth  of  a  pint  ap- 
proximately, or  116  CO. 

Standard  Solutions,  fob,  Analysis 

The  following  are  the  strengths  of  the  standard  solutions  recommended. 

1.  Nitrate  of  Silver. — 4-79  grammes  recrystallised  silver  nitrate  per  htre 
of  water.    1  c.c.  precipitates  1  milligramme  of  chlorine. 

2.  Indigo  Solution  of  such  strength  that  1  c.c.= ^Lth  milligramme  N2O5 
=1  c.c.  of  a  solution  of  0*187  gramme  KNO3  per  litre  of  water. 

8.  Plienol-sulphuric  Acid. — 2  volumes  melted  absolute  phenol,  5  vol. 
pure  oil  of  vitriol,  about  5  vol.  distilled  water,  and  1\  vol.  strong  solution  of 
HCl  (see  p.  279). 

Potassium  nitrate  for  use  with  the  above,  0*7215  gramme  per  litre  of 
water. 

4.  Metaphenylene-diamine  Hydro -chlorate. — 1  gramme  in  200  c.c.  dis- 
tilled water,  acidulated  with  sulphuric  acid. 

Silver  nitrite  for  use  with  this,  0-405  gramme  AgNOa  precipitated  with 
KCl  and  made  np  to  a  litre.  This  is  dilated  10  times  for  use,  when  each 
1  c.c.  =  xsT)^^  milligramme  N^Og. 

5.  Nessler's  Solution. — 35  grammes  potassium  iodide,  13  grammes 
mercuric  chloride,  and  160  grammes  caustic  potash  to  a  litre.  If  not  sensi- 
tive, add  more  of  a  solution  of  mercuric  chloride. 

6.  Chloride  of  Ammonium. — 3-15  grammes  ammonium  chloride  to  a 
litre  of  water.     Each  1  c.c.  =  1  milligramme  NH3. 


296  HYGIENE 

A  solution  prepared  by  diluting  the  above  100  times  ;  each  1  c.c.  rio^^ 
milligramme  KHy. 

7.  Alkalised  Potassium  Permanganate. — 8  grammes  potassium  perman- 
ganate and  200  grammes  stick  caustic  potash  in  1250  c.c.  distilled  water. 
Boil  down  to  1  htre. 

8.  Potassium  Permanganate  for  oxygen  process,  0-28G  gramme  per  litre 
of  water. 

9.  Sodium  Hyposulphite. — 0*77  gramme  sodium  thiosulphate  ('  hypo ') 
in  a  litre  of  water. 

10.  Lead  Acetate. — 2*62  grammes  in  a  litre  of  water. 

11.  Copper  Sulphate. — 5"6  grammes  to  a  litre  of  water. 

12.  Calcium  Sulphate  (for  hardness). — 0"1905  gramme  selenite  in  a 
litre  of  water  (=8°  hardness,  Clark's  scale).  It  is  used  for  '  setting '  soap 
solution. 

13.  Ferrous  Ammonium  Sulphate. — 0-7  gramme  of  the  crystallised  double 
salt  in  a  htre  of  water.     Each  1  c.c.=-yV  niilligramme  iron. 

14.  Soap  Solution. — 9  c.c.  give  a  permanent  lather  with  50  c.c  of  a  solu- 
tion of  calcium  sulphate  (CaS04-2H20)  containing  0-1965  gramme  in  a  Htre 
of  distilled  water. 


BACTEEIOLOGICAL   EXAMINATION. 

Many,  if  not  most,  waters  contain  bacteria,  as  Avas  shown  by  Dr.  Burdon 
Sanderson  ('  Twelfth  Eeport  of  Medical  Officer  of  Privy  Council,'  1870,  p.  229); 
and  there  are  several  methods  used  for  the  bacteriological  examination  of 
water.  These  methods  have  not,  however,  come  into  general  use,  because 
no  means  are  knoAATi  which  enable  the  microscopist  and  analyst  to  dis- 
criminate between  pathogenic,  zymogenic,  and  presumably  inert  bacteria  by 
mere  inspection.  The  bacteria  of  unwholesome  water  hquefy  gelatine 
cultivation-media  more  readily  than  those  from  wholesome  waters  ;  but  this 
summary  embraces  most  that  is  known  of  the  subject  of  the  significance  of 
bacteria  in  di'inking-water.  Some  chemists  attach  importance  to  the 
number  of  colonies  of  organisms  which  may  be  developed  in  a  cultivation- 
area  by  moculation  with  the  water  ;  but  it  cannot  be  said  that  it  is  certainly 
known  that  there  is  any  definite  relation  between  the  number  of  organisms 
a,nd  the  miwholesomeness  of  the  water.  To  Koch  is  due  the  merit  of  having 
introduced  exact  methods  of  discriminating  between  various  kinds  of 
bacteria. 

Dr.  Angus  Smith's  method  is  a  good  one  for  recognising  that  micro- 
organisms are  present  in  water,  though  less  useful  in  determining  their 
characters.  It  consists  in  introducing,  by  means  of  a  capillary  sterilised 
pipette,  drops  of  the  fluid  into  gelatine  or  gelatine-broth  in  test  tubes 
plugged  A\ith  sterilised  cotton-wool,  and  heated  to  35°-40°  C.  (95°-104°  F.). 
The  tubes  are  then  shaken  so  as  to  distribute  the  uioculated  liquid  through 
the  gelatine,  which  is  then  allowed  to  cool  and  set.  After  a  few  days  the 
colonies  of  organisms  that  liquefy  gelatine  may  be  recognised  as  clusters 
disseminated  through  the  gelatine  (which  they  liquefy).  The  size  of  the 
clusters,  their  appearance  and  groupings,  are  then  noted.  Dr.  Percy  Frank- 
land  ('Proceedings  of  Koyal  Society,*  vol.  xxxviii.,  1885,  p.  379)  and  Dr. 
Warden,  of  Calcutta  ('  Chemical  News,'  vol.  lii.,  1885,  pp.  52,  QQ,  73,  89, 
and  101)  have  pubHshed  valuable  methods  of  determining  the  relative 
numbers  of  micro-organisms  present  in  waters,  by  means  of  plate  cultiva- 
tions.    This  may  be  done   by  adding  a  measured  small   quantity  of  the 


WATEB  297 

water  to  be  examined  to  a  definite  quantity  of  liquefied  sterilised  nutrient 
gelatine,  in  a  sterilised  test  tube.  The  mixture  is  well  shaken  and  poured 
into  a  glass  plate,  placed  beneath  a  bell  glass  in  a  moist  chamber,  and  kept 
at  a  temperature  of  70°-72°  F.  (21°-22°  C).  After  a  few  days  the  number 
•of  colonies,  their  shape,  size,  colour,  and  other  characters,  may  be  noted. 

Dr.  Klein  ('  Micro-organisms  and  Disease,'  3rd  ed.,  p.  49)  recommends 
the  following  method  for  the  examination  of  any  sample  of  water  for  micro- 
organisms. The  water  is  allowed  to  stand  for  a  few  hours,  till  most  of  the 
particulate  matter  has  subsided,  and  then  a  little  of  the  fluid  and  sediment 
is  withdrawn  by  means  of  a  long  capillary  pipette.  Some  of  the  fluid  and 
sediment  thus  removed  is  used  for  microscopic  examination  whilst  fresh  ; 
whilst  another  portion  is  prepared  after  the  "Weigert-Koch  method,  by 
spreading  out  the  fluid  on  a  cover-glass  in  a  thin  layer,  drying  it,  fixing  by 
passing  three  times  through  a  flame,  staining  with  a  suitable  aniline  dye, 
such  as  methyl-blue,  magenta,  or  gentian-violet ;  washing  successively  with 
water,  alcohol,  and  distilled  water  ;  drying,  and  then  mounting  the  preparation 
in  Canada  balsam  dissolved  in  benzene  or  xylol.  Test  tubes  containing 
sterilised  cultivation  material — such  as  agar-mixture,  gelatine,  or  Pasteur's 
fluid,  are  also  inoculated  with  the  fluid  in  the  pipette,  by  piercing  the  plug 
of  cotton-wool  with  this.  The  test  tubes  are  then  placed  in  the  incubator 
for  a  day  or  two,  and  then  a  portion  is  withdrawn  by  means  of  a  capillary 
pipette,  and  used  for  microscopic  examination  in  order  to  ascertain  what 
kinds  of  organisms  are  present ;  for  the  unaided  eye  generally  suffices  after 
;a  day  or  two's  incubation  to  ascertain  whether  organisms  are  present  or  not. 
New  cultivations  may  also  be  made  from  the  first  cultivation. 

The  following  method  of  plate  cultivation  is  recommended  on  good 
authority  ('  Crookshank's  Manual  of  Bacteriology,'  2ud  ed.,  pp.  72  and  367). 
A  shallow  glass  dish  is  placed  on  a  tripod  stand,  filled  with  water,  covered 
with  a  glass  plate,  and  the  level  carefully  adjusted  by  means  of  a  spirit- 
level,  which  is  then  removed,  and  replaced  by  a  piece  of  filter-paper  the  size 
of  the  glass  plates  to  be  used,  and  then  covered  with  a  bell-glass.  The 
glass  plates  are  put  into  an  iron  case  and  steriKsed  in  a  hot-air  steriliser 
heated  to  150°  C.  (302°  F.),  where  they  are  kept  for  an  hour  or  two.  The 
-water  in  the  dish  is  now  cooled  by  means  of  crushed  ice  ;  a  sterilised  plate 
is  removed  from  the  box  by  means  of  sterilised  forceps,  held  between  the 
finger  and  thumb  by  opposite  edges,  and  rapidly  transferred  to  the  filter-paper 
on  the  glass  plate.  The  vessel  containing  sterilised  gelatine  is  warmed  in  a 
vessel  of  water  heated  to  30°  C.  (86°  F.),  inoculated  with  the  sample  by 
means  of  a  sterilised  pipette,  and  well  mixed  by  shaking,  avoiding  the 
formation  of  air-bubbles  ;  the  bell-glass  is  raised,  and  the  gelatine  is  poured 
on  to  the  plate,  the  plug  being  previously  removed,  and  the  gelatine  is 
quickly  spread  over  the  plate  by  means  of  a  sterilised  glass  rod  to  ^dthin 
ialf  an  inch  of  the  border  of  the  plate.  The  bell-glass  is  replaced,  and  the 
gelatine  allowed  to  set.  When  quite  set,  the  plate  is  transferred  to  the 
"damp  chamber. 

In  two  or  three  days  the  cultivation  may  be  examined,  and  the  colonies 
•counted ;  and  for  this  purpose  a  glass  plate  ruled  into  square  centimetres, 
.arranged  on  a  frame  so  that  it  may  be  placed  over  the  plate  containing  the 
•cultivation,  may  be  requisite,  so  that  the  number  of  colonies  beneath  one 
square,  and  the  number  of  liquefying  colonies  also,  may  be  counted.  In- 
dividual organisms  may  then  be  examined  by  means  of  cover-glass  prepara- 
tions, and  by  further  inoculations  of  nutrient  gelatine  and  other  media. 

Dr.  Dupre  ('  Eeport  of  the  Medical  Officer,'  iii  14th  Eeport,  1884,  p.  304; 
1.5th  Eeport,  1885,  p.  309  ;  and  17th  Eeport,  1887,  p.  272,  of  the  Local 


298  HYGIENE 

Government  Board),  lias  investigated  the  changes  effected  in  the  aeration  of 
waters  by  the  Hfe  processes  of  particular  micro-organisms  mider  different  con- 
ditions of  temperature,  light,  and  nutrient  material ;  but  all  that  can  at  pre- 
sent be  said  is,  that  some  organisms  cause  the  disappearance  of  oxygen  under 
the  influence  of  organic  matter  in  the  light,  others  only  in  the  dark. 

Dr.  W.  K.  Smith  in  the  preliminary  report  on  the  Differentiation  and 
Identification  of  Micro-Organisms  found  in  Water-supplies  ('  Eeport  of  the 
Medical  Officer,  17th  Eeport,  1887,'  p.  2G8)  has  investigated  the  micro-organisms 
in  the  water  supplied  by  two  of  the  London  Water  Companies.  His  method 
was  to  make  gelatine  plate  cultivations  at  20°  C.  (G8°  F.),  and  agar  plate 
cultures  at  30°  C  (8G°  F.) ;  and  with  the  organisms  thus  developed  mice  were 
inoculated ;  but  in  no  case  was  any  noteworthy  result  obtained.  He  did  not 
detect  any  disease-producing  organism,  but  colonies  of  microphytes  of  multi- 
farious character,  such  q.s  Bacilhis  fl^iorescens  liqiiescens,  Staplycocciis  flaviis 
liqucscens,  Bacillus  erythrosporus,  and  others  whose  identity  with  knowa 
organisms  was  not  established.  But,  whatever  method  be  adopted,  the 
information  afforded  is  at  present  of  very  limited  value,  for  (1)  all  the  orgaji- 
isms  introduced  into  the  culture  medium  may  not  be  capable  of  propagation 
in  this  latter ;  (2)  each  colony  may  possibly  be  the  produce  of  one  or  more 
individual  organisms,  but  this  is  not  likely  ;  (3)  accidental  contamination  of 
a  water  after  coliecdon  may  readily  occur. 


CnAEACTEEISTICS   OF   GOOD   DEINKING-^yATEE 

In  their  celebrated  '  Sixth  Eeport,'  the  Elvers'  Pollution  Commissioners 
made  the  following  weighty  remarks  : — 

'  In  respect  of  wholesomeness,  palatability,  and  general  fitness  for  drinking 
and  cooking,  our  researches  lead  us  to  the  following  classification  of  waters 
in  the  order  of  their  excellence,  and  founded  upon  their  respective  sources. 

[1.  Spring  water \        Very 

J  2. 


'  Wholesome     .   J  2.  Deep-well  water j    palatable. 

I  3.  Upland  surface  water     .         .         •         '  |  Moderately 

•  Suspicious      .   J  ^-  ^^^^^^  ^'^^'^  ^'^*^^'  •        ;         •         •         •   ^    palatable. 

I  5.  Surface  water  from  cultivated  land         .    | 

[  G.  Eiver  water    to    which    sewage    gains   (  p„]„|„uig  > 

'Dangerous      .  -  access 

(  7.  Shallow- well  water        .        .        .        .  j 

And  they  urge  that  preference  should  always  be  given  to  spring  and  deep 
well  water  for  purely  domestic  purposes,  over  even  upland  surface  water,  not 
only  on  account  of  the  much  greater  intrinsic  chemical  purity  and  palatability 
of  these  waters,  but  also  because  their  physical  qualities  render  them 
peculiarly  valuable  for  domestic  supply,  since  they  are  almost  invariably 
clear,  colourless,  transparent  and  brilliant — qualities  which  add  greatly  to 
their  acceptability  as  beverages ;  whilst  their  uniformity  of  temperature 
throughout  the  year  renders  them  cool  and  refreshing  in  summer,  and 
prevents  them  from  freezing  readily  in  winter.  Their  inestimable  value  to 
communities  in  these  respects  are,  however,  in  some  degree  neutralised  as 
regards  temperature  when  they  have  to  be  stored ;  and  too  often  the 
quantities  available  are  inadequate  to  supply  the  needs  of  large  communities 
and  too  costly.  Hence,  we  find  that  for  large  towns,  upland  surface  water- 
supphes  are  now  being  largely  adopted;    as  witness  Glasgow  from  Loch. 


WATEB  299- 

Katrine,  Manchester  from  Lake  Thirlmere,  and  Liverpool  from  Lake  Vyrnwy. 
Often,  too,  it  is  desirable,  and  more  especially  in  the  case  of  a  manufacturing 
community,  to  have  not  only  an  organically  pure  and  a  palatable,  but  also  a 
soft  water  supply ;  and  here  the  advantage  of  an  upland  surface  water 
becomes  manifest. 

The  geological  strata  through  which  a  spring  or  deep  well  water  has 
percolated  will  greatly  influence  its  palatability.  Whilst  surface  waters  are 
often  vapid  and  tasteless,  or  have  a  peaty  bitter  flavour,  in  percolating 
through  deep  rocky  strata,  oi^ganic  matter  is  oxidised  ;  and  such  waters  are 
often  highly  charged  with  carbonic  acid  gas,  which  renders  them  brisk  and 
palatable.  The  waters  drawn  from  the  deep  artesian  wells  in  the  Thames 
basin  are  often  deficient  in  oxygen,  and  faintly  opalescent.  Some,  too,  con- 
tain traces  of  sulphuretted  hydrogen,  and  require  exposure  to  the  air  to 
render  them  palatable  ;  whilst  others,  again,  when  stored  become  filled  with 
confervoid  growths.  The  spring  waters  of  the  magnesian  limestone  forma- 
tion are  not  only  excessively  hard,  but  contain  such  a  proportion  of  mag- 
nesian salts  as,  in  the  opinion  of  most  authorities,  render  them  unfit  for 
drinking  purposes.  A  pure  magnesian  water  may  nevertheless,  it  is  thought 
by  many,  form  a  good  water  for  domestic  use.  The  experience  of  Sunderland 
and  Bristol  is  not  unfavourable  to  the  use  of  magnesian  waters.  The  deep 
well  waters  of  some  of  the  beds  of  the  New  Eed  Sandstone  are  rich  in  gypsum 
as  well  as  in  chalk,  and,  though  palatable,  are  excessively  hard. 

Various  arbitrary  standards  have  been  laid  down  defining  the  amounts 
of  organic  matter,  as  measured  by  one  or  other  of  its  elementary  constituents, 
permissible  in  drmking-water.  All  are  more  or  less  unsatisfactory ;  for  it  is 
the  kind  rather  than  the  amount  of  organic  matter  that  renders  this  injurious. 
All  recent  advances  in  medicine  point  to  the  presence  of  organised  organic 
matter,  or  possibly  definite  chemical  bodies  the  products  of  changes  evoked 
by  organisms,  as  the  potent  factors  in  producing  those  diseases  referrible  to 
the  use  of  polluted  water.  Hence,  standards  having  reference  to  the  quality 
rather  than  the  quantity  of  organic  matter  present  in  waters  are  desirable  ; 
but  no  such  satisfactory  standards  have  been  hitherto  devised.  There  are, 
however,  the  three  modes  of  detecting,  or  rather  gauging,  the  quantity  of 
organic  matter  present  in  a  water  already  described ;  and  these,  by  the  aid  of 
other  data  often  available,  enable  the  practitioner  in  public  health  to  arrive 
at  a  satisfactory  conclusion  as  to  the  potability  or  the  probable  noxious 
character  of  a  water.  These  methods  are,  the  organic  combustion  process 
of  Dr.  Frankland,  the  Wanklyn  process,  and  the  permanganate  process 
respectively,  and  are  commonly  known  by  the  names  of  those  chemists  ;  and 
the  permanganate  is  often  referred  to  as  Dr.  Tidy's  process,  he  having 
improved  upon  the  older  permanganate  processes  previously  used.  The 
assessment  of  the  values  to  be  attached  to  each  of  the  determinations  of  a 
water  analysis,  and  to  the  whole  determinations  collectively,  is  a  subject  on 
which  the  greatest  diversity  of  opinion  has  existed  among  chemists,  and 
which  still  exists  to  some  extent.  It  is  chiefly  over  the  determinations  of 
organic  matter,  and  the  determinations,  such  as  the  amount  of  oxygen 
absorbed  from  permanganate,  which  serve  as  indices  to  the  amount  of 
organic  matter,  though  not  directly  serving  as  measurers  of  this,  that  the- 
battle  of  water-analysis  has  raged  most  furiously ;  but  most,  perhaps,  of  all 
as  to  relative  values  of  the  figures  obtained  by  the  Frankland  combustion 
and  the  Wanklyn  albuminoid  ammonia  processes.  The  writer  of  this  article 
is  of  opinion  that  a  water  must  be  judged — so  far  as  it  can  be  judged  by 
analysis  alone — by  the  whole  results  of  the  analyses,  and  not  by  one  con- 
stituent, be  it  organic  nitrogen  or   albuminoid  ammonia,  alone.     But  he- 


300  HYGIENE 

deprecates,  nevertheless,  the  attempt  made  by  the  late  Mr.  Wigner  and  by 
other  members  of  the  Society  of  PubHc  Analysts  ('  Analyst,'  1881,  vol.  vi., 
p.  Ill)  to  attach  a  numerical  value  to  the  amount  of  each  one  of  the  impor- 
tant constituents,  such  as  total  solids,  hardness,  chlorine,  ammonia,  &c., 
and  then  to  assess  the  impurity  of  a  water  by  a  summation  of  those  numbers, 
e.g.  saying  that  the  impurity  of  a  water  is  20,  10,  17,  &c.,  as  the  case  may 
be.  The  values  attaching  to  the  determinations  of  the  several  constituents 
of  a  water  will  now  be  briefly  discussed  ;  but  it  will  be  well  first  to  set  out 
the  opinions  of  some  leading  authorities  as  to  the  deductions  to  be  drawn 
from  analytical  analyses  of  waters. 

Dr.  Franlvland  thiis  classifies  waters  according  to  their  organic  purity 
('Water  Analysis,'  p.  80)  :— 

Upland  Sukface  Wateb 

Class  I.  Wafer  of  great  organic  purity,  containing  a  proportion  of 
organic  elements  (organic  carbon  and  organic  nitrogen)  not  exceeding  0*2 
part  in  100,000  parts  of  water. 

Class  11.  Water  of  mcdiitm  purity,  conizhmng  fi-om  0*2  to  0*4  part  of 
organic  elements  in  100,000. 

Class  III.  Water  of  doubtful  purity,  containing  from  0*4  to  0*6  part  of 
organic  elements  in  100,000. 

Class  IV.  Impure  ivater,  containing  more  than  O'G  part  of  organic 
elements  in  100,000. 

Watek  othek  than  Upland  Surface 

Class  I.  Water  of  great  organic  purity,  containing  a  proportion  of 
organic  elements  not  exceeding  O'l  part  in  100,000. 

Class  II.  Water  of  medium  purity,  containing  from  0*1  to  0*2  part  of 
organic  elements  in  100,000. 

Class  III.  Water  of  doubtful  purity,  containing  from  0*2  to  0*4  part  of 
organic  elements  in  100,000. 

Class  IV.  Impure  ivater,  containing  upwards  of  0'4  part  of  organic 
elements  in  100,000. 

Dr.  Frankland  thus  further  classifies  waters  {ibid.,  p.  97)  : — 

1.  Beasojiably  safe  waters. — Water,  although  it  exhibits  previous  sewage 
or  animal  contamuiation,  may  be  regarded  as  reasonably  safe  when  it  is 
derived  either  from  deep  wells  (say  100  feet  deep)  or  from  deep-seated 
springs,  provided  that  surface  water  be  carefully  excluded  from  the  weU  or 
spring,  and  that  the  proportion  of  previous  (sewage)  contamination  do  not 
exceed  10,000  parts  in  100,000  parts  of  water  (i.e.  the  inorganic  nitrogen 
does  not  exceed  0-968  part  per  100,000,  or  0-678  grain  per  gallon, — T.S.). 

Suspicious,  or  doubtfiol  water  is  (1)  shallow-well,  river,  or  flowing 
water  which  exhibits  any  proportion,  however  small,  of  previous  sewage  or 
animal  contamination  ;  and,  2nd,  deep-well  or  spring  water  containing  from 
10,000  to  20,000  parts  of  previous  (sewage)  contamination  in  100,000  parts 
of  water  (i.e.  0-968  to  1*92  part  inorganic  nitrogen  per  100,000,  or  0-678  to 
1-344  grain  per  gallon). 

Dangerous  water  is  (1)  shallow-well,  river,  or  flowing  water  which  ex- 
hibits more  than  20,000  parts  of  previous  animal  contamination  in  100,000  ; 
(2)  shallow  well,  river,  or  flowing  water  containing  less  than  20,000  parts 
of  previous  (sewage)  contamination  in  100,000  parts,  but  which  is  known, 
from  an  actual  inspection  of  the  well,  river,  or  stream,  to  receive  sewage, 


WATER  301 

either  discharged  into  it  directly,  or  mingliBg  with  it  as  surface  drainage  ; 
(3)  as  the  risk  attending  the  use  of  all  previously  contaminated  water 
increases  in  direct  proportion  to  the  amount  of  such  contamination,  the 
water  of  deep  wells  or  deep-seated  springs  exhibiting  more  than  20,000 
parts  of  previous  contamination  in  100,000  must  be  regarded  as  dangerous. 
Eiver  or  running  water  should  only  be  placed  in  the  second  class  pro- 
visionally, pending  an  inspection  of  the  banks  of  the  river  and  tributaries, 
which  inspection  will  obviously  transfer  it  either  to  the  class  of  reasonably 
safe  water  if  the  previous  contamination  be  derived  exclusively  from  spring 
water,  or  to  the  class  of  dangerous  water  if  any  part  of  the  previous  con- 
tamination be  traced  to  the  direct  admission  of  sewage  or  excrementitious 
matters. 

Dr.  Tidy  thus  formulates  his  own  conclusion  as  to  the  respective  merits 
of  the  various  processes  for  the  determination  of  organic  matter  in  water 
('  Journal  of  Chemical  Society,'  vol.  xxxv.,  1879,  p.  96) : — 

1.  As  regards  the  ammonia  process,  an  absolute  or  nearly  absolute 
freedom  from  albuminoid  ammonia  is  for  the  most  part  an  indication  of 
organic  purity.  Nevertheless,  many  waters  which  are  very  impure  give  a 
trace  only  of  albuminoid  ammonia,  whilst  some  which  are  very  pure  give 
large  quantities  of  albuminoid  ammonia.  Its  results,  therefore,  are  marked 
by  singular  inconstancy. 

2.  That  the  ammonia  process  allows  of  no  sufficiently  large  scale  where- 
by the  finer  grades  of  purity  or  impurity  can  be  recognised  and  classified. 
The  errors  arising  from  many  causes — such  as,  amongst  others,  the  ammonia 
present  in  the  permanganate  solution  itself,  the  difference  in  time  required 
by  different  organic  bodies  for  their  complete  destruction,  the  chances  of  the 
organic  nitrogen  becommg  oxidised,  the  constant  multiplication  of  errors 
of  observation  resulting  from  collecting  several  distillates  in  which  the 
ammonia  is  to  be  severally  determined,  and  which  errors  are  again  doubled 
in  order  to  convert  results  into  parts  per  million — form  an  array  of  difficulties 
likely  to  lead  to  serious  errors,  seeing  that  the  range  (viz.,  from  0-05  to  0*1 
part  per  million)  between  waters  of  extraordinary  organic  purity  and  dirty 
waters  is  comparatively  small. 

3.  That,  as  regards  the  combustion  process,  the  necessity  for  evaporating 
the  water  to  dryness  constitutes  a  difficulty,  the  chances  being  that  some  of 
the  organic  matter,  and  possibly  that  subtle  form  of  organic  matter  specially 
active  in  producing  disease — the  very  organic  matter,  in  fact,  the  detection 
of  which  the  sanitarian  expects  from  the  chemist — may  be  either  mechanically 
carried  off,  or  volatilised,  or  oxidised,  or  even  destroyed  under  the  peculiar 
conditions  of  the  evaporation. 

4.  That,  barring  this  objection,  the  estimation  of  the  organic  carbon  in 
the  water  residue  is  trustworthy,  repeated  experiments  with  the  same  water 
yielding  constant  results. 

5.  That  the  estimation  of  the  organic  nitrogen  is  by  no  means  so  con- 
stant, the  possibility  of  the  nitrate  not  being  completely  reduced,  especially 
when  present  in  quantity  ;  of  impurities  in  the  sulphurous  acid  solution  ;  of 
occluded  nitrogen  in  the  metallic  copper  ;  and,  lastly,  the  necessary  error  of 
experiment,  constituting  a  series  of  difficulties  which  must  somewhat  impair 
the  nitrogen  determination. 

6.  Under  such  circumstances,  the  process  can  scarcely  be  considered  to 
yield  absolutely  trustworthy  evidence  (unless  the  organic  nitrogen  be  beyond 
a  certain  quantity)  on  which  to  found  an  opinion  as  to  the  probable  source  of 
the  organic  matter  in  the  water. 

7.  As  regards  the  oxygen  process,  he  claims  for  it  that  it  is  conducted  on 


302  HYGIENE 

the  original  -water  and  without  the  application  of  heat.  Hence  we  avoid  the 
evils  both  of  gain  and  of  loss  arising  from,  and  incident  to,  the  evaporation 
of  the  water  to  dryness  at  high  temperatures.  Moreover,  the  analysis  can 
be  conducted  ^\ith  the  smallest  possible  amount  of  handling,  or  of  pouring 
the  water  fi-om  vessel  to  vessel. 

8.  That  the  process  gives  results  of  great  constancy  and  of  extreme 
delicacy.  They  admit,  moreover,  of  a  very  wide  scale  in  their  classifica- 
tion. 

9.  That  the  oxygen  process  allows  us  to  draw  a  sharp  distinction  between 
the  putrescent  or  readily  oxidisable  organic  matter,  which  is  the  more  likely, 
to  use  Dr.  Frankland's  term,  to  be  '  pernicious,'  and  the  non-putrescent  or 
less  readily  oxidisable  matter,  which  is  probably  harmless  so  far  as  its  action 
on  the  human  body  is  concerned. 

10.  That  the  general  inorganic  constituents  of  the  water  have  no  action 
on  potassic  permanganate. 

11.  The  inorganic  constituents  most  likely  to  be  present  in  a  water  that 
would  interfere  with  the  estimation  of  the  organic  matter  by  potassic 
permanganate  are  nitrites,  metallic  protoxides  (especially  ferrous  salts),  and 
sulphuretted  hydrogen,  all  of  which  are  certain  to  be  detected  in  the  course 
of  a  proper  and  complete  water  analysis,  and  corrections  made  accordingly. 

12.  That  in  the  oxygen  process  the  only  modifying  circumstances  are 
those  which  would  render  the  oxygen  required  by  the  water  excessive,  and 
that  therefore,  although  we  might  be  led  to  report  unfavourably  on  a  harm- 
less water,  the  results  obtained  would  never  lead  us  to  report  favourably  on 
a  bad  water. 

13.  That  whilst  he  does  not  consider  that  the  oxygen  process  can  be 
employed  with  scientific  precision  as  a  direct  quantitative  test  of  the  total 
organic  impurity  of  a  water,  nevertheless  the  results  afforded  by  it  indicate 
with  sufiicient  precision  the  comparative  quantity  present  Ukely  to  be  injurious 
to  health. 

14.  That  the  results  obtained  by  the  ox3'gen  process  must  at  all  times  be 
controlled  by  the  natural  history,  as  weD  as  by  the  general,  chemical,  and 
physical  examination  of  the  water. 

15.  That,  so  far  as  the  three  processes — viz.  the  combustion  process,  the 
ammonia  process,  and  the  oxygen  process — are  concerned,  the  oxygen  and 
the  combustion  processes  give  closely  concordant  results,  whilst  the  results 
yielded  by  the  ammonia  process  are  often  at  direct  variance  with  both. 

After  a  full  consideration  of  the  respective  merits  of  the  Forchammer, 
or  oxygen,  and  the  combustion  processes,  Dr.  Frankland  ('  Water  Analysis,' 
p.  57)  gives  the  following  scale  of  classification  of  drinking-waters,  suggested 
by  Dr.  Tidy  and  himself  : — 

Upland  Surface  Water 

Class  I. — "Water  of  great  organic  purity,  absorbing  from  permanganate  of 
potash  not  more  than  0*1  part  of  oxygen  per  100,000  parts  of  water,  or  0'07 
grain  per  gallon. 

Class  II. — "Water  of  medium  purity,  absorbing  from  0*1  to  0'3  part  of 
oxygen  per  100,000  parts  of  water,  or  0-07  to  0'21  grain  per  gallon. 

Class  III. — "Water  of  doubtful  purity,  absorbing  from  0-3  to  0-4  part  per 
100,000,  or  0-21  to  0-28  grain  per  gallon. 

Class  IV. — Impure  water,  absorbing  more  than  0*4  part  per  100,000,  or 
0'28  grain  per  gallon. 


WATEB  303 


Water  other  than  Upland  Surface 

Class  I. — Water  of  great  organic  purity,  absorbing  from  permanganate 
of  potash  not  more  than  0"05  part  of  oxygen  per  100,000  parts  of  water,  or 
0-035  grain  per  gallon. 

Class  II. — Water  of  medium  purity,  absorbing  from  0*05  to  0'15  part  of 
oxygen  per  100,000,  or  0'035  to  O'l  grain  per  gallon. 

Class  III. — Water  of  doubtful  purity,  absorbing  from  0'15  to  0'2  part  of 
oxygen  per  100,000,  or  0"1  to  0'15  grain  per  gallon. 

Class  IV. — Impure  water,  absorbing  more  than  0'2  part  of  oxygen  per 
100,000,  or  0'15  grain  per  gallon. 

Mr.  Wanklyn's  standards  of  organic  purity  are  as  follows  ('  Water 
Analysis,'  p.  68) : — 

Glass  I, — Water  of  extraordinary  organic  purity,  yielding  from  -00  up  to 
•05  part  of  albuminoid  ammonia  per  million.  This  class  comprises  the 
most  carefully  prepared  distilled  water  and  highly  filtered  waters,  both 
natural  (i.e.  deep  spring  waters)  and  artificial  (i.e.  such  water  as  has  passed 
through  a  '  sihcated  carbon  filter'  in  good  working  order).  Occasionally  a 
river-water  in  its  unfiltered  condition  falls  into  this  class.  Water  of  this 
class  cannot  be  objected  to  organically. 

Class  II.  comprehends  the  general  drinking-waters  in  this  country.  It 
gives  from  0*05  to  0*10  part  of  albuminoid  ammonia  per  milhon.  Any 
water  falling  fairly  into  this  class  is  safe  organically. 

Class  III.  comprehends  the  dirty  waters,  and  is  characterised  by  yielding 
more  than  O'lO  part  of  albuminoid  ammonia  per  million. 

The  writer  is  of  opinion  that  no  water  should  be  judged  by  the  quantity  of 
any  one  or  two  constituents  which  it  may  contain,  but  that  the  composition  of 
a  water  as  a  whole  should  be  taken  into  consideration  in  passing  judgment 
upon  its  presumable  safety  when  used  as  a  drinking-water,  and  its  admis- 
sibihty  as  a  source  of  domestic  supply.  To  rely  upon  organic  carbon,  or 
albuminoid  ammonia,  or  ammonia,  or  oxygen  (from  permanganate)  con- 
sumed, may  lead  to  the  rejection  of  a  good,  or  to  the  adoption  of  a  bad 
water.  It  may,  therefore,  be  advisable  to  offer  some  observations  upon  the 
various  constituents  of  waters. 

Gases. — Waters  vary  considerably  in  the  proportions  of  their  gaseous 
constituents.  When  freely  exposed  to  the  air,  a  good  water  which  is  not 
consuming  oxygen  by  means  of  the  organic  matter,  nitrites,  or  ferrous  salts 
which  it  contains  ought  to  contain  about  If  cubic  inches  of  oxygen  per 
gallon ;  and,  to  be  palatable,  to  contain  a  fair  proportion  of  carbonic  acid 
gas  in  solution,  so  as  to  be  brisk  and  not  vapid  in  flavour. 

Odour. — There  should  be  none  ;  but  the  presence  of  a  trace  of  sulphuretted 
hydrogen  odour  when  freshly  drawn  from  a  deep  source  is  not  prohibitory  of 
its  use. 

Taste. — This  should,  of  course,  be  agreeable,  and  not  distinctive  of  any 
special  substance,  subject  to  the  qualification  just  given. 

Turbidity. — There  should  be  none  ;  or,  if  any,  this  should  be  due  to 
vegetable  or  mineral  matters,  and  easily  removable. 

Colour. — There  should  be  none  ;  but  a  slight  peaty  colouration  is  no  bar 
to  the  use  of  the  water. 

Keeping -Powers. — A  good  drinking-water,  when  kept  in  a  bottle  loosely 
plugged  with  sterihsed  cotton-wool,  should  not  become  putrid,  nor  deposit 
anything  beyond  an  inconsiderable  amount  of  chalky  matter. 


304  HYGIENE 

Total  Solids. — The  amount  of  solids  iii  a  good  drinking-water  is  a  very- 
variable  amonnt,  and  depends  a  good  deal  on  tlie  geological  stratum  of  the 
district.  Dr.  E.  Parkes  was  of  opinion  that  a  good  potable  water  should 
not  contain  more  than  35  grains  per  gallon  of  solids,  or  50  per  100,000. 
As  a  matter  of  fact  these  may  range  from  4  per  gallon,  or  6  per  100,000, 
to  50  or  60  grains  per  gallon  or  80  per  100,000  ;  and  no  doubt  even  these 
last  figures  may  exceptionally  be  exceeded.  Some  of  the  best  artesian 
well-waters  in  London  contain  over  50  grains  per  gallon  of  solids,  much  of 
which  is  common  salt ;  and  the  highly  valued  table-waters  imported  from 
the  Continent  contain  nearly  100  grains  per  gallon  of  mineral  constituents, 
or  140  per  100,000.  It  is,  indeed,  rather  the  quality  than  the  quantity  of 
mineral  matter  present  which  is  to  be  regarded  in  judging  of  the  suitability 
of  a  water  for  domestic  use.  As  a  rule,  however,  those  waters  which  con- 
tain least  mmeral  matter  are  deemed  most  suitable  for  domestic  supplies, 
though  there  is  high  authority  for  thinking  that  a  certain  amount  of  chalk 
in  a  water  is  beneficial.  In  one  respect  this  is  an  advantage,  for  such 
waters,  being  slightly  alkaline,  act  but  little  on  lead ;  whereas  the  soft  waters 
containing  little  solid  matter  are  often  acid,  and  act  freely  upon  leaden  pipes 
and  cisterns. 

Loss  on  Ignition. — The  loss  which  the  dry  solid  matter  obtained  by 
evaporation  of  the  water  under  examination  undergoes  when  ignited  is 
nowadays  but  little  regarded.  When  coupled  with  the  manner  in  which 
the  solids  behave  during  the  burning  process,  this  determination  is,  however, 
a  valuable  one.  The  blackening,  the  odour,  and  the  character  as  regards 
colour  and  acidity  of  the  fumes  evolved  should  by  no  means  be  neglected, 
for  in  this  way  the  experienced  analyst  will  obtain  valuable  information. 
The  actual  amount  of  loss — correction  being  made  for  the  substitution  of 
the  N2O5  radical  of  nitrates  by  the  CO2  radical  of  carbonates  during  ignition 
— is  also  an  index  of  quality,  provided  chlorides  and  sulphates  are  not  very 
abundant.  When  these  are  present,  the  loss  is  increased  by  the  loss  of  water 
of  hydration  of  these  salts  not  expelled  at  the  temperature  at  which  the 
water  residue  was  dried  in  the  oven.  In  an  undoubtedly  good  water  the 
loss  on  ignition  is  small — 1  or  2  grains  perhaps  per  gallon — and  the  residue 
during  ignition,  though  it  may  assume  a  shade  of  brown  or  grey,  never 
really  blackens  or  evolves  the  odour  of  burnt  feathers. 

Hardness. — The  use  of  a  water  of  more  than  20  degrees  of  hardness 
(Clark's  scale)  is  undesirable  ;  and  an  ordinary  good  water  ought  not  to 
have  more  than  15  degrees  of  hardness.  The  use  of  a  water  of  25  degrees 
of  hardness  is,  however,  permissible  when  no  softer  water  is  available.  The 
permanent  hardness  of  a  good  water  should  not  exceed  5  degrees. 

Nitrates. — The  nitrogen  as  nitrates  should,  in  no  case,  exceed  1  grain 
per  gallon  ( =  3-86  grains  N2O5) ;  0-7  gram  N  (  =  2-7  grains  N2O5)  per  gallon 
is  a  safer  Hmit. 

Nitrites.- — ^These  should  be  absent. 

Ghlorijie. — If  the  chlorine  exceeds  1*5  grain  per  gallon,  its  source  should 
be  inquired  into  ;  and  if  there  be  also  much  ammonia,  and  especially 
albuminoid  ammonia,  or  organic  carbon  present,  or  if  the  water  consumes 
much  oxygen  in  the  permanganate  process,  sewage  contamination  may  be 
apprehended.  The  deep  artesian  well  waters  of  the  London  basin  contain 
much  chlorine  and  ammonia,  and  are  wholesome ;  but  they  yield  little 
organic  carbon  and  albuminoid  ammonia,  and  they  consume  little  oxygen 
(from  permanganate). 

Organic  Matter. — The  loss  on  ignition  should  not  exceed  2  or  3  grains 
per  gallon  of  water,  and  the  fumes  evolved  during  ignition  should  have  no 


WATER  305 

animal  odour.  The  evolution  of  ruddy  acid  vapours  indicates  excess  of 
nitrates.  Albuminoid  ammonia  should  not  exceed  0*01  grain  per  gallon 
(0"15  per  million)  except  in  the  case  of  peaty  waters,  when  the  albuminoid 
ammonia  is  evolved  slowly.  Ammonia  (so-called  '  free '  ammonia)  ought 
not  to  exceed  0*002  grain  per  gallon,  except  in  the  case  of  an  artesian  well- 
water.  If  the  oxygen  consumed  in  the  permanganate  process  exceeds  0*2 
grain,  or  at  most  0"25  grain  per  gallon,  the  purity  of  the  water  is  open  to 
grave  suspicion.  Organic  carbon  should  not  exceed  0-3  grain  per  gallon, 
nor  organic  nitrogen  exceed  0-03  grain  per  gallon  ;  and  whenever  the  ratio 
of  organic  C  to  N  is  less  than  5  to  1,  the  water  is  open  to  suspicion. 

Only  one  or  two  of  the  determinations — organic  carbon  plus  organic 
nitrogen,  albuminoid  ammonia,  oxygen  consumed — are  usually  employed  in 
conjunction  with  the  other  analytical  data  in  judging  of  the  quality  of  a 
water-supply.  Koch  is  of  opinion  that  a  normal  water  is  one  which  contains 
less  than  300  germs  in  each  cubic  centimetre.  Plugge  and  Kroskauer  would 
not  permit  more  than  50  to  150  germs  at  the  most,  and  the  Swiss  Society  of 
Analytical  Chemists  fixed  the  latter  figure  as  their  maximum.  A.  Pfeiffer 
condemns  a  water  when  the  germs  reach  1000  per  cubic  centimetre  (Ferd. 
Fischer,  *  Zeitsch.  f.  Angew.  Chemie,'  1889,  No.  18).  These  conclusions  are 
widely  diverse,  and  no  account  is  taken  of  the  kinds  of  germ  met  with. 
It  is  obvious  that  until  we  have  some  means  of  distinguishing  between 
innocent,  and  perhaps  beneficent,  germs  and  those  which  are  disease- 
producing,  the  mere  counting  of  germs  is  a  valueless  operation. 

Injurious  Metals. — The  water  should  yield  no  colouration,  or  only  the 
faintest  tint  of  colour,  on  the  addition  of  tincture  of  galls  (absence  of  excess 
of  iron),  and  it  should  not  darken  on  the  addition  of  a  drop  of  sulphide  of 
ammonium  followed  by  a  drop  or  two  of  strong  hydrochloric  acid  (absence  of 
lead  and  copper). 

BIBLIOGEAPHY 

Eeports  of  the  Eivers  Pollution  Commission  (1869),  1  to  10. 

Eeport  of  the  Eoyal  Commission  on  Water  Supply,  1869. 

A  Manual  of  Practical  Hygiene.     By  E.  A.   Parkes.    Edited  by  J.  Lane  Hotter. 

8th  ed.     1891. 
Experimental  Eesearches.     By  E.  Frankland.     1877.     Chapters  on  Drinking  Water, 

pp.  551-683. 
Water  Analysis  for  Sanitary  Purposes.     By  E.  Frankland.     2nd  ed.     1890. 
Water  Analysis.    By  J.  A.  Wanklyn  and  E.  T.  Chapman.     7th  ed.     1889. 
The  Organic  Analysis  of  Potable  Waters.     By  J.  A.  Blair.     1890. 
Potable  Waters.    By  C.  Ekin.     1880. 


VOL.  I. 


THE  INFLUENCE  OF  SOIL  ON  HEALTH 


BY 


S.  MONCKTOJSr  COPEMAN,  M.A.,  M.D.Cantab.,  D.P.H. 

ASSISTANT    LECTtJREB    ON  PHYSIOLOGY    AT    ST.    THOlLiS'S    HOSPITAL 
LATE  SCHOLAR,  EXHIBITI03SrER,  AND  PRIZEMAN  OF  CORPUS  CHRISTI  COLLEGE,  CAMBRIDGE 


x2 


THE   INFLUENCE    OF    SOIL   ON   HEALTH 

Fbom  the  times  of  Herodotus  and  Hippocrates  to  the  present  day,  evidence 
has  been  gradually  accumulating  as  to  the  influence  exerted  by  the  nature  of 
the  soil  on  the  prevalence  of  certain  diseases,  more  particularly  malaria,  to 
which  must  now  be  added  cholera,  diarrhoea,  typhoid  or  enteric  fever,  phthisis, 
and  many  others  which  will  be  treated  of  in  detail  later  on. 

By  the  term  soil  is  understood  such  portion  of  the  earth's  crust  as  has 
been  formed  by  the  gradual  disintegration  through  many  ages  of  the  rocks  of 
which  the  globe  is  mainly  constituted.  The  composition  of  the  soil  therefore 
varies  considerably  in  different  localities,  but  in  comparing  one  with  another 
it  is  well  to  bear  in  mind  the  many  other  factors,  in  addition  to  the  compo- 
sition and  condition  of  the  soil,  which  from  time  to  time  may  come  into  play. 

A  subdivision  into  surface  soil  and  subsoil  is  generally  recognised,  and  is 
useful  for  practical  purposes,  seeing  that  the  upper  portion  of  the  soil  or 
'  mould '  differs  very  materially  from  the  subsoil  in  composition.  The  latter 
consists  for  the  most  part  of  inorganic  materials,  while  the  former  may 
contain  in  addition  large  quantities  of  organic  matter,  both  animal  and  vege- 
table in  origin,  the  role  of  which  is  a  most  important  one,  since  it  is  in  great 
measure  to  these  constituents,  and  the  manner  in  which  they  are  affected  by 
varying  degrees  of  moisture,  temperature,  and  aeration,  that  the  effect  pro- 
duced on  the  health  of  the  community  is  due. 

Above  the  rock  which  will  be  found  at  the  lowermost  portion  of  a  section 
perpendicular  to  the  surface  of  the  earth,  we  find  then  the  subsoil,  which 
results  from  the  breaking  up  of  the  rock  under  the  influence  of  various 
agencies,  such  as  the  percolation  of  water  containing  various  gases  and  other 
substances  in  solution,  or  from  the  irresistible  onslaught  of  the  roots  of  trees 
which,  forcing  their  way  gradually  downwards,  spht  it  asunder.  The  subsoil 
is  thus  continually  eatmg  its  way  into  the  rock  beneath,  to  compensate  for 
which,  influences  are  as  continually  at  work  causing  an  imperceptible  removal 
of  material  from  the  surface  of  the  soil.  Above  the  subsoil  again  we  find  a 
layer  penetrated  in  all  directions  by  the  rootlets  of  the  vegetation  on  the  sur- 
face, indicating  a  still  further  stage  in  the  decay  of  the  remains  of  the  primi- 
tive rock.  This  layer  forms  the  true  soil ;  the  subsoil  being  an  intermediate 
band  where  the  progress  of  decomposition  has  not  advanced  so  far. 

If  there  is  so  intimate  a  connection  between  the  soil  at  the  surface  and 
the  rock  underneath,  we  can  readily  understand  that  soils  should  vary  from 
one  district  to  another  according  to  the  nature  of  the  underlying  rocks. 
Denudation  of  clays  will  produce  clayey  soil,  sandstones  sandy  soil,  or  where 
these  two  kinds  of  rock  occur  together,  they  may  give  rise  to  sandy  clay  or 
loam.  Hence,  knowing  what  the  underlying  rock  is,  we  may  usually  infer  what 
must  be  the  character  of  the  overlying  soil,  or  from  the  nature  of  the  soil,  we 
may  form  an  opinion  respecting  the  quality  of  the  rock  that  hes  below  (GeiMe). 
The  soil  of  every  locality,  then,  ought  to  be  merely  the  decayed  upper  surface 
of  the  rocks  underneath,  mingled  with  the  remains  of  animal  and  vegetable 
matter,  were  it  not  for  the  action  of  rain  and  other  forces  in  removing  material 
to  a  greater  or  less  distance  from  its  source,  by  which  in  some  instances  a  good 
soil  is  laid  down  upon  rocks  which  of  themselves  would  only  produce  a  poor  one. 


310 


HYGIENE 


Since  soils  are  formed  more  or  less  directly  from  the  decomposition  of 
rocks,  it  will  be  advisable  to  mention  shortly  the  manner  of  origin  of  these 
rocks,  and  also  their  chemical  composition. 

The  various  rock-formations  have  been  di%^ded  under  two  principal  heads 
according  to  their  mode  of  origin  :  the  igneous  and  sedimentary  rocks.  The 
first  class,  which  includes  only  a  few  of  the  rocks  with  which  we  are  now  ac- 
quainted, is  believed  to  have  been  derived  from  the  gradual  coohng  down  of 
the  outer  surface  of  the  molten  mass  of  wliich  the  globe  at  first  consisted, 
whence  their  name.  Although  the  proportion  of  igneous  rocks  cropping  up 
above  the  surface  in  Great  Britain  is  so  small  (even  in  North  Wales,  where 
they  are  found  to  the  greatest  extent),  still  they  are  none  the  less  of  importance, 
seeing  that  to  their  decomposition  the  origin  of  the  later  rocks  is  due.  Of 
the  igneous  rocks  the  most  important  is  granite,  which  may  exist  in  many 
different  forms,  and  after  this  the  trap  rocks,  including  the  greensands  and 
basalt,  which  are  looked  upon  by  some  as  essentially  the  primary  rocks  from 
the  considerable  resemblance  which  they  show  in  chemical  composition  to 
volcanic  lava. 

Granite  of  various  kinds  consists  mainly  of  quartz,  feldspar,  and  mica  in 
various  proportions,  although  any  one  of  these  three  constituents  may  be 
absent,  or  replaced  by  some  other  substance.  Thus  a  rock  in  which  horn- 
blende replaces  mica  is  known  as  syenite,  while,  if  both  these  substances  are 
present,  it  is  termed  syenitic  granite.  Gneiss,  again,  contains  the  usual  ele- 
ments of  granite,  but  the  crystals  of  quartz  and  feldspar  are  broken  and  in- 
distinct. The  trap  rocks  consist  mainly  of  feldspar  and  hornblende  (or  augite, 
which  contains  less  sihca  than  hornblende),  and  the  general  composition 
of  the  minerals  composing  the  igneous  rocks  may  be  shown  as  follows : — 

Analyses  of  Minerals  {Lloyd) 


Hornblende                       Mica 

Feldspar 

Without 
Alumina 

Witli 
Alumina 

Potash 

Potash 
Orthoclase 

Soda 
Albite 

SocTa  .... 

Alumina 
Manganese  oxide 
Calcium  oxide  (lime)  . 
Magnesium  oxide 
Potash 
Ferrous  oxide 
Ferric  oxide 
Silica .... 
Loss  on  ignition . 

15-06 
23-92 

2-41 

54-71 
3-33 

3-14 
6-31 
1-13 

9-68 
3-62 
2-65 

21-72 
6-62 

42-27 
-48 

4-10 
36-23 

•50 

•37 

6-20 

1-34 

44-60 

5-26 

17-50 

1-25 

12-00 

1-75 
66-75 

11-47 
19-43 

•20 
69-00 

99-43 

97-62 

98-60            98^25 

100^10 

Quartz  is  not  mentioned  in  the  table,  as  it  consists  of  almost  pure  silica 
alone.  Mica,  hornblende,  and  feldspar,  on  the  other  hand,  are  of  a  much 
more  complicated  nature,  the  main  difference  between  hornblende  and  feld- 
spar being  seen  in  the  large  amount  of  lime  and  magnesia  present  in  the 
former,  while  in  the  latter  there  is  much  potash  or  soda,  but  practically  no  lime. 

'  Thus  the  igneous  rocks  consist  mainly  of  four  elements  :  quartz,  feldspar, 
hornblende,  and  mica.  From  the  decomposition  of  these  rocks,  and  re-forma- 
tion of  the  decomposed  parts,  the  aqueous  rocks  have  been  formed.'  The 
terms  aqueous  or  sedimentary  are  therefore  used,  because  it  appears  that  these 
rocks  must  have  resulted  from  the  gradual  solution  and  disintegration  by 
rain  of  the  older  igneous  rocks,  the  fine  particles  of  which,  held  in  suspen- 
sion in  the  water  of  streams,  lakes,  and  seas,  have  thus  been  carried  to  lower 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  311 

levels  and  then  again  gradually  deposited,  the  resulting  deposits  constantly 
increasing  and  forming  accumulations  of  greater  or  less  thickness,  and 
becoming  arranged  in  layers  or  strata  from  the  separation  of  the  particles 
of  various  size  and  shape.  From  this  cause  arise  the  differences  in  the 
mechanical  and  chemical  composition  of  the  various  sedimentary  rocks,  which 
from  the  fact  that  they  have  either  been  formed  by  deposition  in  water  in 
the  manner  described,  or  by  precipitation  of  matter  held  in  sokition  by  the 
water,  all  resemble  one  another  in  forming  more  or  less  distinct  layers. 
For  this  reason  the  term  stratified  has  been  applied  to  thorn  ;  the  relative 
time  of  their  formation  having  given  rise  to  the  geological  terms  of  primary, 
secondary,  and  tertiary,  by  which  the  three  main  groups  are  distinguished. 

These  principal  divisions  of  stratified  rocks  include  about  eighteen  distinct 
strata,  on  each  of  which  a  special  name  has  been  bestowed.  The  more  impor- 
tant of  these  are : — 

The  old  red  sandstone. 

The  new  red  sandstone  (sandstone  and  marl). 

The  greensand  formation  (sandstone,  clay,  and  sand). 

/Lias. 
Oxford. 
The  claystone  formations  -^  Kimmeridge. 

Wealden. 

VLondon. 

(Mountain  limestone. 
The  limestone  formations  <  Magnesian        ,, 

[Oohtic  „         (Bath  stone). 

The  chalk  formation. 

From  these  various  rocks  the  overlying  soil  has  been  for  the  most  part 
formed  partly  by  the  process  of  'weathering,'  but  also  in  large  part  by  the 
action  of  both  animal  and  vegetable  life.  As  the  plants  on  the  surface  die, 
their  remains  gradually  rot,  as  do  those  of  others  that  succeed  them,  so  that 
by  the  gradual  accumulation  of  the  debris  of  successive  generations,  the  sur- 
face soil  becomes  more  or  less  black,  and  is  found  to  consist  largely  of  organic 
matter  of  vegetable  origin.  The  animal  world,  too,  is  not  unrepresented, 
since  not  only  those  creatures  which  naturally  live  in  the  earth  in  such 
enormous  numbers,  such  as  various  insects  and  earth-worms,  contribute  their 
quota  after  death  to  the  constituents  of  the  soil,  but  larger  animals  as  well 
which  fell  when  dead  upon  the  surface  of  the  earth,  or  were  purposely  buried 
beneath  it,  and  thus  in  either  case  become  in  time  incorporated  with  it.  The 
excrement  of  the  animal  world  also  is  constantly  being  added  to  the  soil,  and 
thus  also  gradually  comes  to  form  an  integral  part  of  it.  In  this  way  from 
both  plants  and  animals  there  is  furnished  to  the  soil  that  organic  matter  on 
which  its  fertility  so  much  depends,  a  fact  the  results  of  which  have  long  been 
known  to  agriculturists,  who  recognise  the  greater  fertility  of  the  upper 
stratum  of  the  soil,  which  differs  in  this  respect  from  that  immediately  below  it. 

It  might  be  supposed  that  the  gradual  formation  of  a  covering  of  soil  and 
subsoil,  particularly  where  there  is  in  addition  an  overlying  abundant  vegetable 
growth,  would  in  course  of  time,  by  the  protection  it  affords,  come  to  prevent 
any  further  decomposition  and  disintegration  of  the  rock  beneath  ;  although 
this  may  be  so  to  a  certain  extent,  the  process  never  ceases  altogether.  If  it 
were  so,  plants  after  a  time  would  cease  to  grow  from  want  of  the  necessary 
inorganic  constituents  of  the  soil,  and  either  the  tract  of  country  would  be- 
come a  waste,  or  at  most  only  the  humbler  forms  of  vegetable  life  would  per- 
sist.    The  continued  growth  of  similar  kinds  of  plants  shows,  however,  that 


312  HYGIENE 

they  are  able  in  some  way  or  other  to  coutinue  obtaining  their  necessary 
nutriment  from  the  soil,  this  in  tmii  depending  on  the  decomposition  of  fresh 
portions  of  the  underlyhig  rock.  This  is  in  fact  due  to  the  actual  growth  and 
decay  of  the  vegetation  itself,  since  rain  falling  on  the  surface  and  gradually 
percolating  through  the  soil  absorbs  certain  vegetable  acids,  the  true  nature 
of  which  is  still  somewhat  obscm'e,  but  which,  when  present  to  a  considerable 
extent,  bestow  on  it  a  power  of  gradually  eating  into  the  substance  of  rocks 
over  which  it  flows.  In  the  case  of  water  issuing  from  extensive  beds  of  peat, 
for  instance,  the  amount  of  these  organic  acids  in  solution  would  be  suflicient  to 
produce  an  appreciable  effect  on  the  stones  or  rocks  with  which  it  came  in  con- 
tact, limestone  rock  being  particularly  liable  to  corrosion  from  such  a  cause. 

In  addition,  rain,  as  it  percolates  through  the  soil,  carries  down  with  it  a 
certain  amount  of  oxygen  and  carbonic  acid  which  it  has  dissolved  from  the 
atmosphere,  while  more  carbonic  acid,  which  is  always  present  to  a  certain  ex- 
tent m  the  soil  itself,  is  dissolved  by  the  water  in  its  downward  passage.  Con- 
stituents of  the  underlying  rock  are  thus  dissolved  which  would  not  be  acted 
upon  by  water  alone.  Limestone  is  particularly  hable  to  be  affected  in  this 
manner,  for  though  only  a  part  of  the  rock  may  become  dissolved,  the  re- 
mainder will  tend  as  the  rock  becomes  exposed  to  become  split  up  into  frag- 
ments by  the  subsequent  action  of  frost.  Carbonic  acid  also  acts  on  iron, 
which  it  dissolves  in  considerable  quantity,  and  it  causes  the  decomposition 
of  feldspar  by  combining  with  the  potash  and  soda  present  in  this  mineral. 
Oxygen  also  acts  on  all  rocks  which,  like  hornblende,  contain  salts  of  iron, 
the  green  ferrous  compounds  being  converted  into  red  ferric  oxide,  and  thus 
disintegration  is  also  brought  about. 

The  conjoined  action  of  water  and  gases  upon  the  rocks,  which  is  termed 
'  weathering,'  is  of  necessity  exceedingly  slow,  but  when  extended  over  periods 
measured  by  centuries,  it  will  be  understood  that  enormous  results  may  be 
produced  by  the  continuous  disintegration  which  goes  on.  "Water,  however,, 
does  not  only  act  by  virtue  of  the  substances  dissolved  in  it,  but  has  a  distinct 
mechanical  action  as  well.  Thus  we  find  that  not  only  the  primary  rocks, 
but  those  of  a  sedimentary  nature  also,  are  frequently  more  or  less  fissured, 
and  if  the  crevices  exist  in  certain  directions  they  will  become  more  or  less 
filled  with  water  after  a  time.  If  now  a  frost  ensues,  the  expansion  of  the 
water  which  occurs,  as  it  becomes  transformed  into  ice,  will  exert  an  immense 
force  which  will  not  only  tend  to  increase  the  extent  of  the  fissure,  but  may 
even  spht  off,  not  only  fragments,  but  also  considerable  portions  of  the  rock. 
Naturally  the  results  of  this  action  will  be  more  obvious  in  temperate 
chmes,  where  there  will  be  alternate  frost  and  moderate  heat  in  winter  and 
summer  respectively,  while  in  tropical  countries,  where  frost  is  unknown,  or 
in  the  arctic  regions,  where  it  is  perennial,  the  results  of  such  will  be  com- 
paratively shght. 

Flowing  water  and  the  movements  of  glaciers  have  also  both  exerted 
considerable  influence  in  this  direction  ;  fragments  of  rock  becoming  broken 
off,  and  these  continually  rolling  against  one  another  are  gradually  broken 
up  into  smaller  pieces,  the  surface  of  the  land  thus  becoming  gradually 
transformed.  Much  of  the  material  thus  broken  up  by  the  influence  of  water 
or  ice  may  be  transported  for  a  considerable  distance  and  then  again  deposited,, 
the  soil  thus  formed  being  termed  alluvial  when  deposited  from  water,  and 
drift  when  the  result  of  glacial  action. 

Of  the  former  class,  the  soils  formed  at  the  mouth  of  large  rivers  such  as 
the  Nile  are  examples,  while  in  England  typical  soils  of  this  character  are 
found  in  the  Fens  of  Cambridgeshire  and  Lincolnshire.  On  the  other  hand, 
drift  action  has  considerably  modified  the  soil  in  many  parts  of  Great  Britain, 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  313 

and  for  the  most  part  improved  it,  since  '  where  slopes  descend  and  are 
covered  more  or  less  with  old  ico-drifts  and  moraine  matter,  the  soil  is  deep 
and  the  ground  is  fertile.  The  re-arrangement  of  the  ice-borne  d&hris  has 
served  to  cover  large  tracts  of  country  with  a  happy  mixture  of  materials, 
such  as  clay  mixed  with  pebbles,  sand,  and  lime.' 

There  is,  moreover,  a  constant  transposition  of  soil  going  on,  not  only 
from  the  washing  away  of  the  surface  by  rain  or  its  removal  by  wind  in  the 
form  of  dust,  these  being  most  noticeable  where  slopes  are  steepest  or  when 
the  weather  is  driest  respectively,  but  from  the  substitution  of  new  surface- 
soil  due  to  the  upraising  of  a  certain  amount  of  material  from  deeper  layers. 
This  is  in  part  brought  about  by  the  labours  of  rabbits,  moles,  and  other 
animals  in  throwing  out  soil  from  their  burrows,  while  in  tropical  countries 
the  termite  or  '  white  ant '  carries  an  enormous  amount  of  fine  earth  up  into 
the  open  air,  forming  hills  in  this  manner  which  may  rise  to  a  height  of  as 
much  as  sixty  feet.  The  most  enormous  amount  of  work  in  this  direction, 
however,  is  performed,  slowly  it  is  true,  but  none  the  less  surely,  by  earth- 
worms. They  disintegrate  the  soil,  riddle  it  with  burrows,  and  so  admit  air 
to  its  deeper  recesses,  and  in  their  castings  bring  up  to  the  surface  an  almost 
incredible  amount  of  fine  soil  in  the  course  of  a  year.  Darwin  has  shoAvn 
that  in  some  places  the  quantity  of  earth  raised  to  the  surface  may  reach  to 
as  much  as  ten  tons  to  an  acre.  Thus  inequalities  tend  to  become  levelled, 
while  stones  and  other  material  of  an  inorganic  or  organic  nature  are  gradually 
buried.  The  organic  and  excremental  matter  thus  buried  becomes  to  a  large 
extent  the  prey  of  various  saprophytic  fungi,  which  abound  in  the  soil  and 
find  in  it  a  pabulum  well  suited  to  their  needs.  In  earth  they  flourish 
to  a  greater  extent  even  than  in  the  atmosphere,  as  might  be  expected,  seeing 
that  the  amount  of  food-material  is  so  abundant,  while  for  the  same  reason 
they  will  be  more  abundant  near  the  surface  than  at  some  distance 
beneath  it. 

BACTEEIA  AND   THEIR  INFLUENCE   ON   SOIL' 

According  to  Fliigge,  enormous  rtumbers  of  bacteria  have  always  been 
found  in  the  soil  by  various  observers.  Infusions  made  from  manured  field 
and  garden  earth,  even  though  diluted  one  hundred  times,  still  contain 
thousands  of  bacteria  in  every  drop,  and  the  ordinary  soil  of  streets  and  courts 
also  shows  the  presence  of  large  numbers.  Bacilli  are  present  in  much  the 
largest  numbers,  but  in  the  most  superficial  layers  and  in  moist  ground  there 
are  also  numerous  forms  of  micrococci. 

Through  the  agency  of  these  bacteria,  organic  substances  which  reach  the 
soil,  and  which  are  for  the  most  part  retained  in  the  superficial  layers, 
undergo  gradual  change,  which  for  the  most  part  is  in  the  direction  of  oxida- 
tion and  occasionally  in  that  of  reduction  or  putrefaction.  That  such  change 
is  brought  about  by  the  vital  activity  of  micro-organisms  is  evident  from 
the  fact  that  if  the  soil  be  sterilised,  as  by  the  action  of  heat,  no  such  meta- 
morphosis takes  place  in  the  chemical  nature  of  its  constituents.  One  such 
property  of  great  importance  possessed  by  soil  in  virtue  of  the  presence  of  some 
one  or  more  of  these  lowly  organisms  is  that  of  nitrification,  as  was  shown  long 
ago  by  Frankland,  who  found  that  the  effluent  from  sandy  soil  over  which 
London  sewage  had  been  passed  was  clear,  and  contained  the  representatives 
of  the  organic  matter  of  the  sewage  .in  the  form  of  nitrates  and  nitrites. 
Experimenting  in  a  similar  manner,  Fodor  found  that  when  a  fluid  contain- 
ing a  considerable  quantity  of  ammonia— a  large  excess  of  organic  material  with 
1  Bacteria  will  be  more  fully  dealt  with  in  a  paper  by  Dr.  Klein. 


314  HYGIENE 

a  trace  only  of  nitrites  and  nitrates— was  poured  over  a  certain  amount  of 
earth,  consisting  of  a  mixture  of  humus  and  sand,  he  recovered  in  the 
filtrate  the  faintest  indication  of  ammonia  only,  about  one-fortieth  of  the 
organic  matter,  and  nearly  fifty  times  the  amount  of  nitrates  and  nitrites. 
He  found,  however,  in  addition,  that  if  the  sewage  were  poured  too  contmu- 
ously  on  to  the  soil,  the  constituents  accumulated  in  great  part  in  the  super- 
ficial layers,  and  failed  to  undergo  a  similar  conversion. 

Schltising  and  Muntz  showed  in  1878  that  the  process  of  nitrification 
•was  dependent  upon  the  presence  of  certain  micro-organisms— that  it  was  in 
fact  a  fermentation  change,  but  they  did  not  succeed  in  isolating  any  one 
form  specially  concerned.  This  has  apparently  been  done  quite  recently  by 
Percy  and  Grace  Frankland,  who,  by  using  a  dilution  method,  have  separated 
what  they  term  a  bacillo-coccus,  which  is  capable  of  inducing  nitrification  in 
ammoniacal  solutions  inoculated  with  it.  Warrington,  however,  in  a  recent 
paper  read  before  the  Chemical  Society,  states  that  the  nitrification  performed 
by  soil  appears  to  be  the  work  of  two  organisms,  one  of  which  oxidises 
ammonia  to  nitrite,  while  the  other  oxidises  nitrite  to  nitrate.  The  first 
organism  is  easily  separated  from  the  second  by  successive  cultivations  in 
solution  of  ammonium  carbonate.  The  second  is  (probably)  separated  as 
easily  from  the  first  by  successive  cultivations  in  solution  of  potassium  nitrite 
containing  monosodium  carbonate. 

It  has  been  shown  conclusively  by  Fliigge,  Koch,  and  others,  that  the 
various  micro-organisms  found  in  soil  are  much  more  numerous  in  the 
superficial  layers  than  at  a  greater  depth.  Indeed,  at  any  distance  from  the 
surface  they  are  practically  absent  unless  the  soil  has  been  deeply  trenched, 
as  in  preliminary  drainage  operations,  or  unless  liquid  filth  from  sewers  and 
cesspools  lias  been  carried  off  beneath  the  soil.  This  is  accounted  for  by 
the  fact  that  the  soil  is  capable  of  retaining  even  such  small  bodies  as 
bacteria,  when  filtration  of  water  or  sewage  is  slowly  carried  on  through  its 
interstices,  although  if  the  filtration  be  more  rapidly  effected  such  bodies  will 
be  carried  to  a  greater  depth.  '  Numerous  filtration  experiments,  on  a  large 
and  small  scale,  have  shown  most  distinctly  that  a  layer  of  earth,  half  to  one 
metre  in  thickness,  is  an  excellent  filter  for  bacteria,  and  hence  the  purifi- 
cation of  fluids  from  bacteria  must  be  still  more  complete  in  cultivated  and 
especially  in  clay  soil,  and  where  the  fluid  moves  with  extreme  slowness. 
Further,  it  has  been  repeatedly  shown  that  wells  which  were  protected  against 
contamination  with  bacteria  from  the  surface  an i, from  the  sides  of  the  well 
furnish  a  "SNater  almost  entirely  free  from  bacteria  ;  that  further,  wells  of 
water  containing  bacteria  become  the  purer  the  more  water  is  pumped  out, 
and  the  more  ground-water  comes  in  from  the  deeper  layers  of  the  soil.' 

That  soil  is  capable  of  thus  acting  as  a  microbic  filter  can  be  shown  by 
the  follo-fting  experiment.  A  flask  A  (fig.  85),  half  filled  with  some  nutrient 
solution  such  as  thin  gelatine  solution  or  peptone  broth,  is  closed  with  a 
tightly-fitting  cork,  through  which  passes  a  glass  tube  B  of  fairly  wide  calibre, 
and  somewhat  constricted  towards  its  lower  end,  which  reaches  down  be- 
neath the  surface  of  the  solution  in  the  flask.  Another  tube  C  simply  opens 
into  the  interior  just  below  the  cork,  in  such  a  manner  that  its  external 
orifice  is  at  right  angles  to  the  other  tube  B.  C  is  now  plugged  with  cotton- 
wool, and  B  is  filled  with  dry  powdered  earth,  which  is  packed  fairly  tightly, 
and  the  whole  apparatus  is  then  sterilised  by  heat.  If  now  decomposing 
mine  be  poured  into  the  upper  end  of  B,  it  will  slowly  filter  through  into  the 
flask,  as  vnW  be  seen  from  the  heightened  level  of  the  contained  fluid,  but 
no  decomposition  will  be  found  to  occur  in  the  gelatine  solution  since  the 
bacteria  will  be  retained  in  B.     To  show  now  that  more  rapid  filtration 


THE  INFLUENCE   OF  SOIL   ON  HEALTH 


315 


will  carry  them  through  into  A,  air  is  blown  through  the  tube  C,  so  as  to 
drive  the  nutrient  solution  in  A  into  B,  say  as  high  as  D.  On  stopping 
the  injection  of  air,  the  fluid  will  again  rapidly  rise  in  A,  and  putrefaction 
will  shortly  set  in. 

That  the  oxidation  of  organic  substances  in  soil,  as  evidenced  by  the 
conversion  of  organic  carbon  into  carbon  dioxide  and  of  nitrogen  into  nitric 
acid,  is  effected  by  the  vital  activity  of  micro-organisms  is  indicated  by  the 
following  observations  of  Fodor  : — 

1.  It  is  checked  or  stopped  altogether  by  aspirating  chlorine  through  the 
soil. 

2.  It  is  favoured  by  a  moderately  high  temperature  thus 


After  the  soil  has  been  kept  at  18°  C.  for  three  days,  amount  of  CO, 

volumes  of  air  aspirated  through  soil 
After  being  warmed  to  60°-65°  C.  . 

65°-95°  C.  . 

95°-105°  C. 

105°-115°  C. 

115°-125°  C. 


in  1,000 

=  1-05 

=  2-30 

=  2-40 

=  1-00 

=  0-58 

=  0-15 


So  that  the  amount  of  carbon  dioxide  increases  when  the  soil  is  heated  to  from 
65°-75°C.,  remains  stationary  afterwards  until  the  temperature  reaches  95°C., 
then  decreases  quickly  and  markedly.  It  does  not  disappear  wholly  even 
when  137°  C.  is  reached. 

3.  Schlosing  and  Muiitz,in  the  course 
of  their  investigations  on  the  influence 
of  organisms  in  the  process  of  nitrifica- 
tion in  soil,  found  that  the  rapidity  of 
the  changes  going  on  was  considerably 
diminished  when  chloroform  vapour  was 
forced  through  the  soil ;  proof  of  this 
fact  being  seen  in  a  decrease  of  nitrates 
and  nitrites  in  the  effluent  accompanied 
by  a  correspondingly  large  increase  in 
the  ammonia. 

4.  Nitrification,  like  other  processes 
of  a  similar  nature  in  the  soil,  is  much 
less  active  than  usual  or  may  cease 
altogether  when  the  soil  has  been 
thoroughly  heated.  Similarly  Falk 
found  that  thymol,  naphthylamine, 
nicotine,  and  other  substances  passed 
undecomposed  through  soil  which  had 
"been  exposed  to  considerable  heat,  while 
they  wholly  disappeared  when  added  to 
soil  which  had  not  been  heated. 

5.  Different  forms  of  bacteria,  espe- 
cially bacilli,  occur  in  almost  all  samples 
of  earth.  As  the  result  of  experiment 
it  would  appear  that   oxidation  is  due 

to  the  vital  activity  of  micro-bacteria,  while  desmo-baeteria  play  a  similar  part 
in  putrefaction,  since  they  are  able  to  thrive  in  the  absence  of  air.  Moreover, 
the  bacteria  concerned  in  nitrification  are  killed  by  exposure  to  a  temperature 
of  between  90°  and  100°  C,  which  suffices  to  kill  micro-bacteria,  but  not  the 
desmo-bacteria.  Thus  the  fact  that  the  formation  of  carbonic  acid  in  soil 
is  greatly  reduced  at  100°  C,  though  not  wholly  stopped  by  a  considerably 


Fig.  85. 


316  HYGIENE 

higher  temperature,  may  be  explained  by  supposing  that  at  the  former  point 
the  micro-bacteria,  the  chief  producers  of  CO  >,  are  killed,  while  the  desmo- 
bacteria,  being  capable  of  resisting  even  a  higher  temperature,  survive  and 
ultimately  regain  their  activity. 

The  temperature  of  the  soil,  and  the  amount  of  moisture  contained  in  it, 
are  both  important  factors  in  determining  the  extent  of  changes  going  on  as 
the  result  of  the  presence  of  micro-organisms.  Thus  it  has  already  been  seen 
that  the  amount  of  COo  produced  in  soil  containing  abundance  of  organic 
substances  increases  up  to  a  temperature  of  about  60°  C,  v\rhile  it  is  almost 
entirely  arrested,  at  a  temperature  of  100°  C.  or  more.  The  amount  of  mois- 
ture most  favourable  to  the  production  of  COo  is  reached  when  water  is  pre- 
sent to  the  extent  of  about  4  per  cent.,  although  the  surface  maj  be  entirely 
covered  with  water,  as  Schlosing  showed  in  his  experiments  on  nitrification, 
without  such  changes  becoming  entirely  arrested.  Should  the  soil,  however, 
be  perfectly  dry,  decomposition  does  not  take  place. 

Ventilation  of  the  soil  is  another  important  factor.  Thus  Fleck  buried 
rabbits  in  gravel,  sand,  and  clay  respectively,  and  found  that  decomposition 
proceeded  more  rapidly  in  sand  and  gravel,  which  allowed  freer  access  of  air, 
than  in  the  more  impermeable  clay.  Fodor  states  that  if  air  be  drawn 
through  a  tube  charged  with  earth  rich  in  organic  matter,  the  carbon  dioxide 
obtained  increases  in  the  same  ratio  as  the  velocity  with  which  the  air  is 
drawn  through  the  tube,  while  Soyka  also  found  that  the  nitrifying  power  of 
soil  increased  when  air  was  passed  constantly  through  it.  This  effect,  how- 
ever, is  not  due  to  an  increased  supply  of  oxygen,  since  Schlosing,  on  aspira- 
ting soil  with  air  containing  different  proportions  of  this  gas,  found  that  when 
more  oxygen  was  supplied  the  production  of  carbon  dioxide  actually  diminished, 
while  on  the  other  hand  a  considerable  amount  of  carbon  dioxide  was  produced 
when  the  aspirated  air  contained  oxygen  to  the  extent  of  only  1  per  cent. 
The  suggestion  has  been  made  that  aspiration  may  act  in  the  manner  de- 
scribed, by  removing  products  inimical  to  the  organisms,  in  the  sense  that 
alcohol  is  inimical  to  the  life  processes  of  the  yeast-fungus,  that  substances 
resulting  fi'om  putrefaction,  such  as  phenol,  indol,  and  skatol,  restrain  the 
growth  of  putrefactive  organisms,  or  that  the  products  of  digestion  retard  the 
further  action  of  digestive  ferments. 

The  kind  of  decomposition  that  goes  on  in  a  given  soil  varies  according 
as  air  reaches  the  contained  organic  substances  in  small  or  large  amount. 
It  varies,  in  fact,  with  ventilation  of  the  soil  and  therefore  with  its  permea- 
bility to  air,  so  that  every  natural  i)henomenon  wliicli  alters  the  ventilation 
of  the  soil  will  also  modify  the  processes  going  on  m  it,  sometimes  favouring 
oxidation,  at  other  times  putrefaction.  Thus  rising  ground- water,  by  stopping 
up  the  pores  of  the  soil,  will  conduce  to  putrefaction,  as  will  also  freezing  of 
the  upper  layer  of  the  soil,  which  destroys  its  permeability  and  thus  favours 
putrefaction  in  the  deeper  and  warmer  portions.  Supersaturation  with  or- 
ganic substances  has  a  similar  effect,  and  hence  the  soil  of  cities  is  prone  to 
undergo  putrefaction  rather  than  oxidation,  both  by  reason  of  its  greater  de- 
gree of  pollution  and  of  the  obstruction  offered  by  pavements  and  buildings 
to  due  ventilation.  That  want  of  air  is  among  the  conditions  for  putrefaction 
is  indicated  by  an  experiment  of  Frankland's  in  which,  when  an  extra  amount 
of  sewage  was  allowed  to  pass  on  to  a  certain  field  used  for  irrigation  pur- 
poses, the  effluent,  which  before  had  contained  considerable  amounts  of 
nitrates  and  nitrites,  now  showed  in  their  place  undecomposed  organic  matter, 
ammonia,  and  certain  faintly- smelling  gases. 

'  The  question  whether  among  the  bacteria  which  are  found  in  the  soil 
some  may  not  be  hurtful  to  mankind  is  of  great  interest  and  importance. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  317 

If  disease-causing  organisms  find  a  nidus  in  the  soil,  may  they  not  multiply 
or  at  least  continue  to  live,  and  then  prove  a  danger  to  health  ?  There 
can  be  no  doubt  that  pathogenic  organisms  do  exist  in  the  soil,  but  their 
power  for  harm  would  seem  to  be  practically  very  small  indeed  ;  and  to 
regard  the  soil  as  dangerous  because  some  pathogenic  orgaaisms  may  lurk  in 
it  would  be  as  rational  as  it  would  be  to  eschew  vegetable  food  because  of 
the  occasional  dangers  of  hemlock,  aconite,  or  the  deadly  nightshade.  It 
seems  to  be  a  fact  that  the  great  doctrine  of  the  "  survival  of  the  fittest  "  holds 
good  for  microbes  in  the  soil,  as  for  all  other  organised  bodies  everywhere  ; 
and  that  organisms  which  flourish  in  the  human  body,  languish  and  cease  to 
multiply  in  the  soil,  where  the  conditions  are  unsuited  for  their  multiplication 
or  even  for  their  survival.  They  get  overgrown  by  saprophytic  microbes, 
and  even  if  they  do  not  die,  the  risk  of  their  finding  their  way  into  the  ground 
water  is  practically  nil,  for  we  have  seen  that  humus  is  the  best  of  filters.' 
(Vivian  Poore.) 

Although  doubtless  the  great  majority  of  bacterial  forms  inhabiting  the 
upper  layers  of  the  soil  are  simple  saprophytes,  organisms  capable  of  inducmg 
certain  specific  diseases  are  not  unfrequently  encountered.  Among  these 
may  be  mentioned  the  bacillus  of  tetanus  (Nicolaier  and  Eosenbach),  of 
anthrax  (Frank),  of  mahgnant  oedema  (Koch  and  Gaffky),  and  of  typhoid 
fever  (Eberth  and  Gaifky).  The  bacillus  of  malaria  described  by  Klebs  and 
Tommasi-Crudeli  should,  perhaps,  be  included,  although  its  pathogenic 
significance  is  not  now  generally  accepted.  In  like  manner,  the  microbe 
which  Professor  Domingos  Freire,  of  Brazil,  discovered  in  a  burial-ground 
near  Eio  Janeiro,  and  which  he  believed  to  be  the  cause  of  yellow  fever,  is 
now  stated  on  independent  evidence  to  have  no  relation  to  that  disease. 
Sherrington  has  isolated  a  pneumococcus  from  laboratory  dust  which  is 
fatal  to  mice  when  inoculated  subcutaneously,  but  whether  it  has  any  patho- 
genic importance  in  relation  to  human  beings  is  at  present  unknown. ^ 

Cholera  bacilli  have  not  hitherto  been  found  in  the  soil,  but  Frankel  has 
shown  experimentally  that  they  can  grow  and  multiply  there  at  various 
depths.  At  a  distance  of  about  four  feet  from  the  surface  their  development 
was  constant  and  progressive  throughout  the  year.  Diarrhoea,  again,  is  a 
disease  as  to  which,  as  the  result  of  Ballard's  researches,  there  is  every  reason 
to  suspect  that  a  definite  micro-organism  is  necessary  for  its  appearance,  and, 
moreover,  that  such  microbe  has  its  normal  habitat  in  the  soil,  although  it 
has  not  as  yet  been  isolated. 

GEOUND  AIR 

All  soils  contain  a  certain  amount  of  air,  the  actual  percentage  depending 
on  the  looseness  or  othervidse  with  which  the  constituent  particles  are  packed 
together.  Many  rocks,  particularly  the  softer  varieties,  also  contain  air,  only 
the  very  densest  forms  being  practically  free  from  it. 

This  air,  which  may  exist  in  loose  sands  to  the  extent  of  about  50  per 
cent.,  or  even  more,  consists  in  great  part  of  carbon  dioxide,  while  oxygen  is 
usually  present  in  smaller  quantity  than  in  atmospheric  air.  This  was 
first  pointed  out  by  Boussingault  and  Levy,  who  in  1852  analysed  air  which 

*  This  was  a  bacillus  found  in  the  dust  of  an  upper  room  in  the  Hygienic  Institute, 
Kloster  Strasse,  Berlin,  in  March  1887.  White  mice  inoculated  with  a  fraction  of  a 
drop  of  the  pure  cultures  died  invariably,  generally  in  about  forty-eight  hours.  Eats 
inoculated  with  it  generally,  but  not  always,  succumbed.  Of  ten  guinea-pigs  inoculated, 
one  only  died.  The  bacillus  in  many  respects  resembled  Friedlander's  pneumococcus, 
a  point  of  distinction  between  them  was,  however,  the  more  perfect  anterobiosis  of  the 
pneumococcus.     Spores  were  not  detected. 


318  HYGIENE 

they  had  aspirated  from  the  soil  at  a  distance  of  1^  feet  from  the  surface, 
with  the  result  that  its  composition  was  found  to  be — 

Oxygen 10-35  per  cent,  of  volume 

Carbon  dioxide 9-74       „  ,, 

Nitrogen 79-91       „ 

Pettenkofer,  next  investigating  the  subject,  confirmed  the  presence  in  the 
ground  air  of  an  amount  of  carbon  dioxide  in  excess  of  that  in  atmospheric 
air,  the  amount  increasing  with  the  depth  from  which  the  air  was  drawn, 
and  being  influenced,  moreover,  by  the  season  of  the  year — the  greatest 
quantity  at  a  given  depth  being  found  in  autumn,  and  the  least  in  spring. 
He  stated  his  opmion  that  this  COo  was  due  to  the  decomposition  of  organic 
substances  under  the  influence  of  atmospheric  air,  which  had  found  an 
entrance  to  the  soil,  and  considered  that  the  CO.2  of  well-waters,  and  possibly 
that  contained  in  the  atmosphere,  were  in  part  derived  from  it. 

Fleck,  in  Dresden,  and  Fodor,  in  Buda-Pesth,  independently  arrived  at 
somewhat  similar  conclusions,  and  the  former  observer  suggested  that  the 
amount  of  carbon  dioxide  might  afford  an  approximate  means  of  estimating 
the  degree  of  pollution  of  the  soil.  This  hypothesis,  however,  is  contraverted 
by  Fodor  and  Eoller,  who  found  that  although  the  CO.3  was  doubtless  pro- 
duced by  the  decomposition  of  organic  substances,  it  did  not  afford  so  much 
an  index  of  the  pollution  as  of  the  permeability  of  the  soil ;  a  very  polluted 
soil,  if  at  the  same  time  very  permeable,  containing  even  a  smaller  amount 
of  CO2  than  a  soil  less  polluted  if  also  less  permeable.  Lems  and  Cunning- 
ham found  that  the  COo  in  the  ground  air  in  the  soil  of  a  field  near  Calcutta 
which  they  examined,  increased  with  the  rainfall  and  decreased  with  dry 
weather,  the  amount  also  being  greatest  in  the  lower  strata  examined.  In 
point  of  fact,  it  appears  certain  that  the  ground  air  consists  for  the  most  part 
of  atmospheric  air,  which  has  penetrated  into  the  pores  of  the  earth,  some 
of  the  oxygen  of  such  air  having  become  converted  into  carbon  dioxide. 
Boussingault  and  Levy,  however,  found  that  a  certam  specimen  of  ground 
air  contained  only  20*09  volumes  per  cent,  of  carbon  dioxide  +  oxygen,  and 
they  supposed,  therefore,  that  a  small  part  of  the  oxygen  had  united  with 
hydrogen  obtained  from  organic  substances  in  the  soil  to  form  water. 

The  oxygen  of  the  air,  then,  on  passing  into  the  soil,  enters  into  chemical 
combination  with  carbon  derived  from  various  animal  and  vegetable  sources, 
and  thus  becomes  replaced  in  some  measure  by  an  equal  volume  of  CO2. 
There  must,  however,  be  other  influences  also  at  work,  since  this  statement 
is  not  invariably  borne  out,  the  percentage  amount  of  oxygen  and  COg 
together  in  the  ground  air  being  sometimes  slightly  higher  and  sometimes 
lower  than  in  the  atmosphere,  a  possible  explanation  of  which  may  be  found 
in  the  union  of  a  certain  portion  of  the  oxygen  with  hydrogen  to  form  water, 
and  with  nitrogenous  organic  bodies  to  form  nitrates.  On  the  other  hand, 
the  CO.2  which  is  formed  may  unite  to  some  extent  with  the  water  in  the 
soil,  and  also  with  alkalies,  such  as  ammonia,  and  the  basic  earthy  salts  to 
form  bicarbonates. 

The  suggestion  has  been  made  that  the  soil  may,  perhaps,  absorb  and 
condense  gases  after  the  manner  of  spongy  platinum,  and  Eoller  cites  some 
experiments  which  would  appear  to  support  this  view,  as  on  driving  air 
through  garden  soil  he  found  rather  less  CO2  in  the  issuing  than  in  the  in- 
going soil,  whereas  with  dry  sand  the  air  passed  through  unchanged.  Fodor 
explains  this  by  inferring  that  although  air  passed  through  moist  and  polluted 
soil  which  had  first  been  heated  and  then  cooled  does  lose  some  of  its  CO2, 
the  loss  is  due  to  the  water  in  the  soil,  which,  losing  its  CO2  when  heated, 
takes  it  up  again  from  the  air  passed  through  the  soil. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  319 

The  carbon  dioxide  in  the  ground  air  may  be  greater  in  amount  than 
would  correspond  to  the  oxygen  absorbed  from  the  atmosphere.  In  such  a 
case  the  excess  of  CO2  is  due  to  the  vital  action  of  putrefactive  organisms, 
which  may  not  only  use  the  oxygen  of  the  atmosphere,  but  also  are  capable 
of  abstracting  the  oxygen  of  organic  substances  and  also  that  of  tlie  nitrates 
in  the  soil.  Thus,  if  a  flask  containing  water  with  organic  substances  in 
solution,  such  as  Cohn's  fluid,  after  a  short  exposure  to  the  air,  be  her- 
metically sealed  up  at  the  neck  and  then  set  aside  for  some  days  in  a  warm 
place,  it  will  be  found  that  if,  after  such  a  lapse  of  time,  the  gases  in  the 
flask  be  collected,  their  volume  may  be  from  35  to  40  per  cent,  above  the 
volume  of  the  air  in  the  flask  before  it  was  sealed  up,  the  contained  gases 
consisting  of  carbon  dioxide  and  nitrogen  in  about  equal  parts,  while  oxygen 
will  be  conspicuous  by  its  absence.  In  this  connection  it  may  be  noted  that, 
as  stated  above,  even  inorganic  substances  are  reduced  in  the  process  of 
putrefaction,  nitrates,  according  to  Pasteur  and  Cohn,  becoming  converted 
into  nitrites,  and  even  into  ammonia.  Thus  Schlosing,  on  drawing  air 
containing  different  amounts  of  oxygen  through  earth  containing  putrefactive 
organisms,  invariably  found  that  carbonic  acid  was  formed,  while  the  amount 
of  nitric  acid  in  the  soil  was  decreased. 

Here  we  find  an  explanation  of  the  fact  that  an  increased  amount  of  gas 
is  found  in  the  lower  layers  of  the  earth,  particularly  in  autumn,  when  these 
layers  are  warmest,  and  when,  therefore,  the  vitality  of  organisms  concerned 
in  decomposition  processes  would  be  most  favoured.  This  was  particularly 
noticed  by  Nicholas,  who  found  an  increase  of  gas  in  the  air  of  his  artificial 
earth  in  summer,  and  a  decrease  in  winter  ;  the  volume  of  oxygen  +  carbon 
dioxide  in  this  earth  at  a  depth  of  fourteen  inches  having  been  in  one  series 
of  experiments  as  follows  : — 

On  June  21 26-2  per  cent. 

On  July  26 26-7 

On  October  16 21-6 

On  November  10 19-7        „ 

Not  only,  then,  does  oxidation  take  place  in  the  soil,  but  putrefaction  also, 
as  is  seen  from  the  fact  that  a  relative  increase  in  the  amount  of  oxygen  and 
carbon  dioxide  may  temporarily  occur.  The  more  polluted  the  soil,  and  the 
more  impermeable  to  air — whether  originally  so,  as  when  it  is  largely  com- 
posed of  clay,  or  whether  rendered  so  artificially  by  the  pores  of  the  upper 
layers  becoming  sealed  up  by  rain — the  more  will  putrefaction  go  on ;  whereas 
under  opposite  conditions  oxidation  alone  will  take  place,  putrefactive  changes 
being  wholly  in  abeyance.  The  presence  of  ammonia  in  the  ground  air  indi- 
cates that  putrefaction  is  going  on  in  it,  and  since  usually  about  four  times 
as  much  ammonia  can  be  obtained  from  the  soil  at  a  depth  of  four  metres 
as  at  about  a  quarter  of  that  depth,  it  would  appear  that  putrefaction  occurs 
more  especially  in  the  deeper  layers,  where  there  is  practically  no  free  oxygen, 
but  where  anaerobic  bacteria  are  known  to  thrive.  There  is,  therefore,  a 
greater  tendency  to  putrefactive  changes  in  the  soil  near  the  ground  water 
than  in  the  more  superficial  layers.     (Fodor.) 

The  nitrogenous  organic  substances  in  the  soil  become  in  course  of  time 
converted  into  nitrates,  which  are  washed  into  the  deeper  layers  by  the  rain, 
becoming  there  reduced  under  the  influence  of  bacteria  into  ammonia.  This 
unites  with  carbonic  acid  there  present,  and  may  again  pass  up  to  the  super- 
ficial layers,  in  solution  in  rising  ground  water,  where  it  is  seized  upon  by 
plants.  For  this  reason  it  will  be  seen  that,  although  ammonia  may  be  found 
in  the  soil,  an  estimation  of  the  actual  amount  present  cannot  be  taken  as 
an  index  of  the  activity  of  putrefactive  changes  which  are  going  on. 


320  HYGIENE 

The  nitrogen  present  in  soil  is  equal  to  that  -wliicli  would  normally  be 
present  in  the  amount  of  atmospheric  air  which  had  penetrated  the  earth. 
There  has,  however,  been  considerable  discussion  as  to  whether  any  of  it 
becomes  absorbed  or  not,  Deherain  maintaining  that  a  portion  of  it  does 
thus  disappear,  while,  on  the  other  hand,  Boussingault,  Schlosing,  and  others 
state  that  it  is  impossible  to  iind  evidence  of  such  absorption.  Occasionally 
sulphuretted  hydrogen  is  found  in  ground  air,  particularly  if  the  soil  be  moist ; 
it  appears  to  be  derived  from  the  sulphates  present  in  the  hard  water  Avith 
wliich  the  soil  is  charged.  Marsh  gas  or  carburetted  hydrogen  also  may 
occm'  as  a  result  of  the  decomposition  of  certain  organic  substances ;  it  may  be 
obtained  from  putrid  mud,  and,  as  in  the  case  of  carbonic  acid  and  ammonia,  is 
found  in  greater  amounts  in  the  deeper  layers.  This  increase  of  it  at  the  greater 
depths  is  mainly  due  to  greater  difficulty  of  ventilation ;  indeed  this  factor  may 
be  even  more  important  tlian  the  pollution  of  the  soil,  as  an  instance  of  which 
may  be  quoted  Fodor's  observation  that  at  one  place  he  found  much  more 
carbonic  acid  at  four  metres  than  at  a  depth  of  two  metres  only,  although 
the  organic  carbon  and  organic  nitrogen  were  in  greater  amount  at  the  former 
point.  As  a  rule,  however,  the  relative  amounts  of  carbon  dioxide  in  samples 
of  ground  air  taken  from  soils  which  have  practically  the  same  degree  of 
permeability  indicate  the  relative  extent  of  impurity  of  these  soils ;  when, 
however,  the  permeabihty  varies,  the  rule  does  not,  of  course,  apply. 

The  actual  amount  of  carbon  dioxide  in  soils  varies,  according  to  Boussin- 
gault's  experiments,  from  2*4  per  1,000  volumes  to  9-74  in  soils  which  have 
been  recently  manured.  In  alluvial  ground  Nichols  found  from  1*49  to  2'26 
volumes  per  1,000  in  air,  drawn  from  a  depth  of  from  3f  to  5^  feet.  Fodor 
gives  as  the  results  of  thirteen  observations  at  a  depth  of  one  metre,  from  8*99 
to  10'39,  and  at  a  depth  of  four  metres  (from  eleven  observations)  from  26*31  to 
54-45  CO2,  while  Pettenkofer  and  Fleck  have  found  it  rise  as  high  as  80  per 
1,000  volumes  in  gravelly  soils  at  depths  of  from  five  to  thirteen  feet. 

Annual  and  Seasonal  Vaeiations  op  CO2  in  Ground  Aik 

It  might  reasonably  be  expected  that  in  spring  more  CO2  might  be  found 
for  a  short  time  in  the  superficial  layers  than  m  those  lower  down,  owing 
to  the  fact  that  these  upper  layers  become  somewhat  suddenly  warmed.  As 
a  matter  of  fact,  both  Pettenkofer  and  Fodor  have  found  that  such  is  the 
case,  the  ground  air  in  spring  having  for  a  longer  or  shorter  period  more 
CO2  at  a  depth  of  one  metre  than  the  air  obtained  from  a  depth  of  two  metres. 
In  autumn,  on  the  contrary,  the  CO2  in  the  superficial  layers  sinks  rapidly, 
and  curves  representing  the  respective  amounts  in  superficial  and  deep  layers 
become  most  widely  separated. 

By  taking  the  average  of  a  large  number  of  observations,  it  appears  that 
the  amount  of  CO2  in  the  soil  rises  in  a  uniform  manner  till  the  height  of 
summer,  and  then  sinks  as  the  temperature  subsides,  and  with  the  exception 
mentioned  above,  the  variations  at  different  depths  show  a  certain  degree  of 
parallelism.  (Plate  II.)  Owing,  however,  to  the  alternation  of  warming  and 
cooling  of  the  soil,  the  CO2  maxima  and  minima  do  not  occur  quite  simulta- 
neously in  all  the  layers  although  the  greater  amount  is  always  found  at  the 
greater  depth,  as  is  shown  in  the  following  table  compiled  by  Fodor  at  Buda- 
Pesth,  as  the  average  of  a  large  number  of  observations  extendiag  over  a  period 
of  three  years. 

The  variations  in  the  amount  of  COo  in  the  soil  ia  different  years  and  at 
different  seasons  depends  on  the  amount  of  decomposition  which  is  going  on ; 
this  in  turn  undergoing  fluctuations  according  to  the  amount  of  the  rainfall 


t,  Tre$-.tise  on  Hygiene  J  PI. 11. 

VoLl, 

The-  Soil  oriy  Ujs  Ilelaiwru  to  Doseouse^. 


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West,lIev/3naLii  iith.. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH 


521 


and  the  prevailing  temperature,  the  effect  of  the  latter  being  very  marked.  Of 
course  this  concurrence  is  most  marked  in  the  superficial  layers  in  which  the 
variation  is  largest,  and  in  which  the  soil  is  most  polluted,  and  in  which  con- 
sequently the  increase  of  warmth  can  effect  the  largest  relative  CO.^  produc- 
tion. In  the  deeper  layers  the  CO2,  as  also  the  temperature,  usually  reaches 
its  maximum  amount  about  a  week  later  than  in  the  superficial  layers. 


Amounts  of  CO^  in  the  ground 

Amounts  of  00^  in  the  ground 

air  as  the  mean  of  observations 

air  as  the  mean  of  observations 

~ 

for  three  years 

for  three  years 

1  metre 

2  metres 

4  metres 

1  metre 

2  metres 

4  metres 

January- 

6-5 

12-6 

25-0 

July     . 

15-8 

228 

359 

February 

6-8 

12-2 

24-8 

August 

12-8 

20-7 

32-6 

March . 

70 

11-8 

24-7 

September   . 

10-9 

19-3 

31-4 

April    . 

9-9 

14-9 

25-2 

October 

9-8 

15-0 

29-4 

May     . 

11-5 

16-1 

27-2 

November    . 

8-4 

13-8 

26-5 

June     . 

14-5 

21-5 

29-2 

December     . 

8-1 

12-6 

25-8 

Rainfall  has  also  a  marked  effect  upon  the  amount  of  CO2  in  the  soil,  an 
increase  of  rainfall  being  quickly  attended  by  an  increase  of  CO2,  while  in  dry 
weather  the  amount  of  CO2  becomes  reduced.  Such  an  increase  after  rain  is 
due  to  the  blocking  up  of  the  pores  of  the  superficial  layers  and  a  consequent 
accumulation  of  CO2  in  the  deeper  portions  of  the  soil,  and  is  almost 
immediately  followed  by  a  fall,  the  CO2  being  absorbed  by  the  wetted  soil. 
This  general  coincidence  between  a  period  of  rainfall  and  a  period  of  eleva- 
tion in  amount  of  carbonic  acid  is,  however,  much  closer  and  more  marked 
in  reference  to  the  carbonic  acid  in  the  upper  than  to  that  in  the  lower  layers 
of  soil,  for,  as  Lewis  and  Cunningham  found  in  the  course  of  their  investiga- 
tions at  Calcutta,  the  amount  of  carbonic  acid  in  the  latter  continues  high 
long  after  the  cessation  of  the  rains,  and  shows  no  immediate  rise  corre- 
sponding with  their  commencement  in  the  following  season. 

Daily  variations  also  occur  to  a  certain  extent,  but  they  do  not  follow  any 
very  definite  rule.  They  depend  not  so  much  on  variations  in  decomposition 
processes  as  on  wind,  rain,  and  changes  of  atmospheric  pressure.  Wind, 
according  to  Pettenkofer  and  Fodor,  sucks  out  the  air  from  the  soil,  and  so 
reduces  the  carbonic  acid  in  it ;  the  latter  observer  having  found  a  decided 
decrease  in  its  amount  on  77  out  of  111  very  windy  days.  Under  certain 
conditions,  however,  an  opposite  result  may  become  apparent  from  the  action 
of  the  wind  forcing  air  into  strata  opposed  to  its  path.  Lewis  and  Cunning- 
ham found,  however,  that  the  velocity  of  the  wind  did  not  appear  to  exert 
any  very  distinct  influence  on  the  amount  of  carbonic  acid  in  the  soil  as  a 
rule,  although,  after  an  extreme  and  continued  elevation  of  the  wind  during 
a  couple  of  months,  they  found  a  sudden  depression  in  the  amount  of  carbonic 
acid  in  the  upper  layer  of  the  soil  in  one  locality,  while  there  was  no  corre- 
sponding depression  in  the  upper  layer  of  the  soil  of  a  second  station  which 
happened  to  be  much  more  shaded  than  the  first.  After  a  long  continuance 
of  still  weather,  they  also  noted  a  marked  elevation  in  amount  of  carbonic 
acid  at  both  places,  probably  due  to  the  diminished  ventilation  of  the  soil 
which  preceded  it. 

Changes  in  atmospheric  press2ire  do  not  exert  any  very  great  influence  on 
the  amount  of  carbonic  acid,  although  it  would  appear  that  on  days  on  which 
the  barometric  pressure  is  very  much  below  that  on  preceding  days,  the 
mean  amount  of  carbonic  acid  in  the  soil  at  a  depth  of  about  three  feet  from 
the  surface  will  be  found  to  have  risen,  the  probable  explanation  being  that 
owing  to  the  ground  air  escaping  on  the  days  of  lozu  pressure  the  ground  air 

VOL.   I.  T 


^322  HYGIENE 

from  the  deeper  layers,  which  is  more  heavily  charged  with  CO2,  rises  into  the 
more  superficial  layers.  "With  an  increase  of  atmospheric  pressure,  on  the 
other  hand,  the  carbonic  acid  shows  no  marked  tendency  either  to  an  increase 
or  decrease  in  amount. 

CUKKENTS  OF   GeOUND   AiR 

From  what  has  already  been  stated  with  regard  to  the  fluctuations  in  the 
amount  of  carbon  dioxide  hi  the  soil,  it  will  be  evident  that  the  subterranean 
atmosphere  which  exists  in  the  soil  is  in  continual  movement.  This  is 
mainly  due  to  variations  in  the  temperature  of  the  eai'th  and  of  the  atmo- 
sphere which  do  not  usually  occur  simultaneously,  the  variations  of  earth 
temperature  for  the  most  part  following  on  similar  variations  in  the  tempera- 
ture of  the  air,  it  being  extremely  rare  for  both  eartb  and  air  to  show  the 
same  temperatui-e,  at  any  rate  for  more  than  a  very  short  time  (Plate  III.). 
Either  the  soil  or  the  air  will  be  the  colder  or  the  warmer,  and  consequently 
the  ground  air  is  continually  moving,  either  passing  from  the  deeper  to  the 
more  superficial  portions  of  the  soil,  or  vice  versd.  Naturally  the  greatest 
range  of  movement  will  occur  when  the  soil  and  air  are  most  difi'erent  in 
temperature.  In  autumn  and  winter  the  soil  is  the  warmer,  and  therefore  the 
air  present  in  it  escapes  into  the  atmosphere,  the  colder  atmospheric  air 
entering  into  the  pores  of  the  soil — this  effect  being  more  marked  the  drier  the 
soil.  For  the  same  reason  the  ground  air  will  pass  up  to  places  where  the 
surface  is  elevated,  being  displaced  by  the  atmospheric  air  which  will  enter 
the  soil  in  low-lying  situations. 

In  spring  and  summer,  on  the  contrary,  the  ground  air  is  colder  and 
denser  than  the  atmosphere,  hence  it  will  tend  to  pass  down  into  the  deeper 
layers  of  the  soil.  On  a  cool  day  following  on  a  hot  one  the  ground  air 
escapes  into  the  atmosphere,  while  on  warm  days  it  remains  stagnant  in  the 
soil.  At  night,  too,  the  warmer  ground  air  will  escape  into  the  atmosphere. 
Beneath  buildings,  such  movements  of  the  ground  air  may  be  very  active, 
particularly  in  the  case  of  houses  that  are  artificially  warmed,  the  air  which 
then  passes  up  from  below  being  often  drawn  from  considerable  depths,  so 
that,  in  the  case  of  houses  which  have  been  built  upon  '  made  soils  '  especially, 
much  unhealthiness  may  result  from  the  aspiration  of  foul  air  from  the 
impure  soil  beneath,  unless  the  precaution  be  taken  of  covering  the  site  with 
an  impermeable  layer  of  asphalte  or  concrete,  or  if  necessary  by  raising  the 
house  from  the  surface  of  the  ground  on  arches.  Similarly,  lealdng  cesspools 
and  drains  may  contaminate  the  soil,  the  air  from  which,  passing  up  into 
houses,  may  most  injuriously  affect  the  health  of  the  inhabitants. 

Kain  sinking  into  the  soil  will  drive  the  ground  air  to  a  deeper  level,  and 
at  the  same  time  will  cause  it  to  escape  at  places  where  the  earth  has  not 
been  wetted.  Variations  of  level  of  the  ground  water  also  will  necessarily 
cause  corresponding  movements  of  the  ground  air  which  lies  above  it,  the 
latter  being  slowly  expelled  from  the  surface  of  the  earth  as  the  ground 
water  rises  and  occupies  the  spaces  between  the  particles  of  the  soil ;  air 
being  again,  sucked  in  as  the  ground  water  falls.  Other  factors  concerned, 
such  as  alterations  of  barometric  pressure  and  the  action  of  wind,  have  aheady 
been  considered  in  connection  with  variations  in  the  amount  of  carbon  dioxide 
in  the  soil. 

The  air  which  fills  the  soil  to  a  depth  of  from  five  to  ten  metres  (15 
to  30  feet)  and  makes  up  almost  one-third  of  its  volume,  can,  even  if  it  move 
but  slowly,  rise  therefrom  in  the  course  of  a  single  night  so  as  to  constitute, 
with  its  contained  moist  foul  gases,  a  considerable  portion  of  the  atmosphere 
of  our  dwellings,  courts,  and  streets. 


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THE  INFLUENCE   OF  SOIL   ON  HEALTH  323 

Estimation  of  Amount  of  Am  in  Soil 
In  order  to  estimate  the  amount  of  air  contained  in  loose  soils,  Pettenkofer 
■advises  the  following  procedure : — A  sample  of  the  soil  to  be  examined  is 
dried  at  a  temperature  of  100°  C.  (212°  F.)  and  then  powdered,  care  being 
taken  to  crush  it  as  little  as  possible.  Two  burettes,  connected  together  at  their 
lower  extremities  with  an  india-rubber  tube  provided  with  a  clamp,  are  supported 
side  by  side  on  an  appropriate  stand ;  into  one  is  put  a  portion  of  the  dried  and 
powdered  soil,  while  the  other  is  filled  with  distilled  water.  The  first  burette 
should  now  be  gently  tapped  to  expel  the  air  as  much  as  possible  from  the  inter- 
stices of  the  soil,  and  the  clamp  opened,  when  the  water  from  the  second  burette 
will  gradually  rise  up  through  the  soil  until  it  appears  as  a  thin  film  above  the 
surface.  As  soon  as  this  occurs,  the  clamp  is  again  closed  and  the  amount 
of  water  which  has  left  the  second  burette  is  to  be  read  off.  The  percentage 
amount  of  air  in  the  soil  is  obtained  as  follows  : — 

Cubic  centimetres  of  water  used  x  100  _      ^centage  of  air. 
Cubic  centimetres  oi  dry  soil 

so  that  if  25  c.c.  of  soil  were  placed  in  the  burette  and  7  c.e.  of  water  were 

7  X 100 

used  to  displace  the  air  in  the  soil,  then  —      —  =  percentage  of  air. 

25 

If  a  piece  of  rock  is  to  be  examined  instead  of  loose  soil,  an  estimation 
can  be  made  in  a  somewhat  similar  manner,  provided  the  rock  is  fairly  porous, 
by  determining  the  amount  of  water  which  it  will  absorb.  This  can  be  fairly 
accurately  gauged  by  first  weighing  the  rock  in  the  dry  state  {x),  then  weigh- 
ing it  in  water  {y),  and  finally  removing  it  from  the  water,  and  again  weighing 
it  while  saturated  with  moisture  [z).  The  calculation  will  then  be  as  follows : — 

(z-x)  100  .  t    ■ 

i '- =  percentage  oi  air. 

x—y 

Estimation  of  Amount  of  Caebon  Dioxide  in  Geound  Aie 
For  this  purpose  Lewis  and  Cunningham,  who  investigated  the  amount  of 
carbonic  acid  in  the  soil  at  depths  of  3  and  6  feet  respectively,  proceeded  in 
the  following  manner.  Two  leaden  tubes  were  procured,  at  one  end  of  each 
of  which  a  hollow  perforated  bulb  was  soldered.  A  pit  was  dug  in  the  soil 
at  a  spot  where  it  was  perfectly  free  from  surface  pollution  and  where  it  had 
probably  not  been  disturbed  for  many  years.  One  of  these  tubes  was  passed 
through  the  bottom  of  an  ordinary  flower-pot,  inverted  and  perforated  in 
numerous  places.  Below  and  surrounding  this  pot  fragments  of  earthenware 
were  arranged  so  as  to  keep  the  earth  from  plugging  the  orifices  in  the  bul- 
bous extremity  of  the  leaden  tube.  The  pit  was  now  filled  up  to  within  three 
feet  of  the  surface  and  the  other  tube  introduced  and  similarly  protected  from 
being  plagged  by  the  fine  soil ;  the  earth  was  then  heaped  up  and  well  beaten 
down,  until  it  reached  the  level  of  the  surface.  Observations  were  not  made 
until  a  considerable  period  had  elapsed,  so  as  to  allow  the  soil  to  regain  its 
ordinary  condition. 

Attached  to  the  aspirator — intervening  between  it  and  the  pipe  leading 
into  the  soil — were  the  usual  appliances  for  estimating  the  amount  of  carbon 
dioxide  by  the  baryta  process,  which  is  fully  explained  in  another  section. 
Briefly  described,  the  method  consists  in  causing  the  air  under  examination 
to  pass  through  a  flask  containing  a  solution  of  baryta  of  known  alkahnity, 
and  subsequently  ascertaining,  by  means  of  a  solution  of  oxalic  acid,  how 
much  of  the  alkalinity  has  disappeared  after  the  passage  through  it  of  the  air 
containing  carbonic  acid — turmeric  paper  being  employed  in  preference  to 
litmus  for  ascertaining  the  precise  stage  at  which  the  solution  becomes  neutral. 

y2 


824  HYGIENE 


WATER   IN   THE   SOIL 
Soil  Moisture 


To  Pettenkofer  is  due  the  credit  of  having  been  the  first  to  dh-ect  attention^ 
by  his  important  investigations,  to  the  subject  of  the  soil  water  in  its  relation 
to  disease.  In  this  connection  it  is  necessary  to  distmguish  between  the 
amount  of  water  mixed  with  air  which  is  present  in  the  interstices  of  the  soil, 
known  as  moisture,  and  the  continuous  subterranean  lake  or  sheet  of  water 
found  in  most  soils  at  varying  depths  from  the  surface,  known  as  ground  water. 
Pettenkofer  defines  this  ground  water  as  that  condition  in  which  all  inter- 
stices are  filled  with  water,  so  that,  except  in  so  far  as  its  particles  are  sepa- 
rated by  solid  portions  of  soil,  there  is  a  continuity  of  water. 

The  amount  oi  moisture  in  the  soil  depends  on  its  power  of  absorbing  and 
retaming  water,  on  the  nature  of  the  subsoil,  the  configuration  of  the  ground, 
and  the  amount  of  water  supplied  by  the  rainfall  or  derived  from  the  ground 
water  below.  It  would  appear  that  wetting  of  the  soil,  when  due  to  a  rise 
of  ground  water,  will  conduce  to  active  putrefaction  in  the  deep  layers,  while, 
the  superficial  layers  remaining  permeable,  the  products  of  decomposition  can 
readily  make  their  way  to  the  surface  of  the  earth,  whereas  when  the  wetting 
of  the  soil  is  due  to  the  rainfall  the  conditions  will  be  different. 

The  nature  of  the  soil  will  influence  considerably  the  amount  of  moisture 
which  it  will  take  up,  although  there  is  no  soil  which  is  not  capable  of  ab- 
sorbmg  a  certain  amount.  Some  porous  soils,  such  as  loose  sands  and 
gravels,  sandstones,  and  chalk,  are  capable  of  taking  up  very  large  quantities  ; 
a  loose  sand  being  said  to  be  capable  of  holding  as  much  as  two  gallons  of 
water  in  a  cubic  foot,  while  ordinary  sandstone  may  hold  one  gallon.  Dried 
quartz  sand  has  been  shown  by  Pfaff  to  have  the  power  of  retaining  about 
20  per  cent,  of  water,  although  under  natural  conditions  the  amount  absorbed 
would  doubtless  not  be  so  great.  Humus  may  take  up  as  much  as  from  40 
to  GO  per  cent,  and  retain  it  strongly,  while  chalk  will  take  up  about  15  per 
cent.,  and  moderately  loose  clay  20  per  cent.  Even  the  most  impermeable 
rocks,  such  as  the  granites,  the  metamorphic  rocks,  dense  clays  and  hard 
limestones,  will  contain  a  certain  amount  of  water  varying  in  the  case  of 
the  driest  granites  from  ^  per  cent,  to  4  per  cent.,  or  an  average  of  about 
three  gallons  in  a  cubic  yard,  between  which  and  the  amount  capable  of 
being  taken  up  by  the  most  permeable  soils  all  gradations  are  found. 

Although  the  soil  moisture  is  in  great  part  regulated  by  the  rainfall,  the 
amount  actually  absorbed  will  depend  on  a  variety  of  circumstances,  such  as 
the  amount  of  evaporation,  which  will  naturally  be  greater  in  summer  than 
in  winter,  the  rapidity  of  the  rainfall— a  large  amount  often  running  off  along 
the  surface  of  the  ground  if  the  downfall  be  severe  at  any  one  time — and  the 
configuration  of  the  land.  In  the  loosest  sands  more  than  90  per  cent,  of 
the  total  rainfall  may  penetrate  the  soil,  while  in  the  case  of  the  chalk  it  has 
been  calculated  at  42  per  cent,  and  with  sandstone  at  25  per  cent,  on  the 
average,  the  remamder  either  evaporating  or  draining  away  along  the  surface. 
As  has  been  said,  the  ground  water  also  influences  the  soil-moisture  by  its 
variations  in  rise  and  fall,  by  evaporation  through  the  upper  stratum  of  the 
soil,  and  by  capillary  attraction,  so  that  the  surface  soil  is  in  these  various 
ways  kept  more  or  less  damp  in  all  parts  of  the  world.  According  to  Fodor, 
the  curve  of  moisture  in  the  more  superficial  layers  of  the  soil  runs  closely 
parallel  with  the  curve  representing  the  amount  of  rainfall.  The  curve  of 
moisture  in  the  deeper  layers,  on  the  other  hand,  runs  closely  parallel  with 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  325 

the  curve  representing  the  varying  levels  of  the  ground  water,  both  attaining 
their  maximum  in  summer  and  early  autumn. 

For  determining  the  amount  of  moisture  in  soil,  a  boring  is  taken  and 
weighed  ;  it  is  then  dried  at  a  temperature  of  110°  C.  and  weighed  again,  when 
the  difference  of  the  two  observations  will  represent  the  amount  sought  to  be 
ascertained,  which  may  conveniently  be  expressed  as  a  percentage.  The  amount 
of  moisture  which  it  is  capable  of  taking  up  may  be  determined  by  placing 
the  previously  dried  soil  under  a  bell -jar,  the  contained  air  being  saturated 
with  moisture. 

In  a  series  of  observations  on  the  amount  of  moisture  held  by  soil  at  varying 
depths,  Fodor  found  that  not  only  did  the  amount  decrease  with  the  depth 
from  the  surface,  but  that  the  amount  varied  a  great  deal  at  all  depths  in  similar 
kinds  of  soil,  even  when  examined  at  the  same  time.  He  considers  that  these 
differences  are  due  to  the  amount  of  organic  substances  in  the  soil,  such 
organic  substances  having  the  effect  of  raising  the  capacity  of  the  soil  for 
absorbing  water  ;  this  theory  being  borne  out  by  the  fact  that  the  amount  of 
moisture  in  the  soil  varies  directly  as  the  amount  of  organic  substances  present. 
The  amount  of  moisture  falls  off  rapidly  as  deeper  layers  are  penetrated,  and 
this  appears  to  correspond  also  with  the  varying  amount  of  organic  substances 
in  the  soil,  the  amount  of  which  diminishes  rapidly  as  we  get  further  from 
the  surface. 

The  amount  of  moisture  not  only  varies  from  year  to  year,  but  from  season 
to  season,  and  even  from  month  to  month,  the  amount  generally  increasing 
in  spring,  reaching  its  maximum  in  May,  and  then  sinking  during  the  summer 
till  late  in  the  autumn.  Here  again  differences  are  noted  according  to  the 
depth,  the  soil  at  from  three  to  six  feet  from  the  surface  being  most  moist  in 
spring,  the  amount  gradually  diminishing  towards  autumn  ;  while  at  a  depth 
of  from  nine  to  twelve  feet  the  soil  is  most  moist  in  summer  and  least  so  in 
autumn.^ 

At  still  shorter  intervals  of  time  the  variations  in  the  amount  of  moisture 
may  be  very  large.  At  from  three  to  six  feet  in  depth  the  amount  of  moisture 
usually  remains  constant,  since,  in  fact,  the  soil  at  these  depths  is  generally 
saturated.  Below  these  levels  the  sinking  rain-water  will  probably  first 
saturate  the  soil,  and  then  running  off  again,  will  in  turn  leave  it  relatively 
dry.  It  is,  however,  the  variations  in  the  layers  down  to  about  six  feet  below 
the  surface  especially  that  are  of  most  interest  practically,  since  these  upper 
layers  will  naturally  be  the  most  polluted,  and  because,  therefore,  processes 
which  influence  health  probably  go  on  in  them  to  a  much  greater  extent  than 
in  the  layers  below.  The  minimum  moisture  found  at  Buda-Pesth  at  one 
yard  from  the  surface  was  5'9  per  cent,  or  59  grammes  of  water  per  1,000 
grammes  of  soil,  while  at  four  yards  it  was  3"2  per  cent. ;  but  since  decom- 
position continues  when  there  is  only  2  per  cent,  of  moisture  present,  and 
is  very  active  when  the  amoimt  reaches  4  per  cent.,  it  is  obvious  that,  as 
far  as  moisture  is  concerned,  oxidation  and  putrefaction  are  particularly 
favoured  at  the  former  level,  while  they  are  less  so  at  greater  depths. 

Ground  or  Subsoil  Water 

A  continuous  sheet  of  water,  termed  ground  water,  is  found  below  the 
surface  of  the  soil,  at  depths  which  vary  very  considerably  in  different  locahties, 
as  occasionally  it  may  reach  to  within  a  few  inches  of  the  surface,  while  in 
other  cases  it  may  only  be  met  with  at  a  hundred  or  more  feet  below  it.  This 
difference  in  level  will  depend  on  the  permeability  of  the  soil,  on  the  nature  and 
inclination  of  the  strata  below  the  surface,  whether  loose  or  compact,  and  on 

'  These  statements  refer  more  particularly  to  Buda-Pesth,  where  Fodor's  experiments 
were  carried  out. 


326  HYGIENE 

the  ease  or  the  reverse  with  which  the  water  can  flow  away  to  some  outlet  iix 
sprmgs,  rivers,  or  the  sea.  The  water  is  in  constant  movement  in  its  en- 
deavour to  reach  such  outlets,  and  the  variations  in  the  level  of  the  ground 
water  caused  by  such  flow  is  best  studied  by  taking  measurements  of  the  level 
of  water  in  wells,  as  has  been  done  in  a  most  exhaustive  manner  by  Petten- 
kofer,  Fodor,  Baldwin  Latham,  and  others,  who  have  insisted  strongly  on  the 
importance  of  such  variation  of  level  of  the  ground  water  as  constituting  a 
weighty  factor  in  the  etiology  of  certain  diseases,  such  as  cholera  and  enteric 
fever. 

Fodor  found  that  at  Buda-Pesth  such  variations  were  regulated  over  the 
greater  part  of  the  city  by  the  varying  level  of  the  Danube,  the  greatest 
fluctuations  being  found  in  the  wells  nearest  the  river ;  while,  on  the  other 
hand,  the  greater  the  distance  from  the  Danube  the  smaller  were  the  varia- 
tions of  the  water  level,  until  at  the  outer  limits  of  the  city  they  almost 
entirely  disappeared. 

Although  the  level  of  the  ground  water  is  thus  constantly  changmg,  the 
difl'erence  between  its  highest  and  lowest  levels  is  usually  not  more  than  a 
few  feet,  while  in  some  instances  the  range  of  movement  may  be  only  a  few 
inches  either  way.  At  Munich  a  difference  of  ten  feet  has  been  noticed,  and 
in  India  it  is  often  much  more  than  this,  a  range  of  i'Z^  ft.  having  been  re- 
corded. Fodor  noted  seasonal  variations  of  the  ground-water  level  which^ 
however,  agreed  very  closely  with  variations  in  the  level  of  the  Danube ;  the 
ground  water  and  that  of  the  river  rising  and  falling,  and  reaching  their 
maximum  and  minimum  at  the  same  time. 

The  rise  was  noticeable  at  the  beguming  of  July  and  continued  through 
August,  the  highest  level  in  each  of  three  years  occurring  about  the  middle 
of  smmner,  and  the  lowest  at  the  end  of  winter  and  beginning  of  spring  ;  so 
that  the  interesting  fact  was  brought  out  that  the  ground  water  is  highest 
when  the  rainfall  is  smallest.  This  was  particularly  noticeable  in  May  1887, 
when,  after  an  exceptionally  heavy  rainfall,  no  marked  influence  on  the  varia- 
tion of  level  of  the  ground  water  in  any  one  of  the  wells  could  be  detected  :  the 
reason  being  that  the  extent  of  the  subsoil  water  at  Buda-Pesth  is  affected  to  a 
much  greater  extent  by  variations  in  the  level  of  the  river  than  by  merely  local 
rainfall.  It  must  not,  however,  be  supposed  that  the  rainfall  never  affects 
the  ground  water,  as  in  some  instances  it  undoubtedly  does  so  ;  but  even  then 
the  effect  may  not  be  visible  until  some  considerable  time  afterwards,  extend- 
ing to  weeks  or  even  months.  On  the  other  hand,  in  low-lyuig  situations, 
such  as  in  plains  at  the  foot  of  hills,  the  level  may  be  raised  by  rainfalls 
occurring  at  far  distant  spots.  The  level  will  also  be  raised  by  any  obstruc- 
tion at  the  outfall,  such  as  may  be  caused  by  the  silting  up  of  a  watercourse, 
or  the  backward  pressure  of  the  sea,  and,  on  the  other  hand,  it  will  be  lowered 
by  any  removal  of  obstruction,  such  as  may  be  secured  by  sldlful  drainage. 
The  immense  distance  at  which  pressure  may  be  exerted  on  the  subsoil  water 
is  shown  by  the  fact  that  the  Danube  at  Buda-Pesth  was  found  by  Fodor  to  in- 
fluence the  level  of  the  water  ha  a  well  at  a  distance  of  2,700  feet  from  that  river. 
De  Chaumont  also  instances  a  place  on  the  Hamble  Eiver  in  Hampshire,  where 
the  tide  was  found  to  affect  the  water  of  a  well  at  a  distance  of  2,240  feet,  the 
well  itself  being  83  feet  deep  and  140  feet  above  mean  water  level.  Similarly, 
the  water  of  a  well  was  affected  by  the  pressure  of  the  water  of  the  Rhine 
at  a  distance  of  1,670  feet. 

The  ground  water  is  constantly  moving  in  a  horizontal  direction,  usually 
flowing  towards  the  nearest  watercourse  or  the  sea  ;  the  rate  of  movement 
depending  on  the  inclination  of  underlying  impervious  strata,  and  the  ease, 
or  the  reverse,  with  which  it  can  eventually  escape,  so  that  it  varies  greatly 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  327 

in  different  places.  Its  rate  of  movement  is  also  influenced  by  the  roots  of 
trees,  as  when  trees  are  removed  it  runs  away  much  more  rapidly.  As  the 
mean  of  a  large  number  of  measurements  as  to  the  time  when  a  rise  in  the 
Danube  was  followed  by  a  rise  of  water  in  the  wells  at  Buda-Pesth,  Fodor 
found  that  the  mean  rate  of  movement  of  the  ground  water  was  53  metres, 
or  174  feet,  in  twenty-four  hours,  with  a  maximum  of  66  metres,  or  215  feet,  in 
the  same  length  of  time.  In  Munich,  Pettenkofer  reckons  the  rate  of  flow  as 
fifteen  feet  daily,  while  high  water  in  the  Elbe  is  stated  to  move  the  adjacent 
ground  water  at  the  rate  of  seven  or  eight  feet  daily. 

The  height  to  which  the  ground  water  extends  is  measured  by  noting  the 
level  of  water  in  wells  in  the  locality  in  which  the  investigation  is  to  be 
carried  out.  For  this  purpose,  Pettenkofer  recommends  that  a  rod  or  rope, 
to  which  a  number  of  small  cups  are  fixed  at  equal  distances,  should  be 
lowered  into  the  well.  On  drawing  them  up  again,  the  highest  one  which 
contains  water  will  obviously  denote  fairly  accurately  the  height  at  which 
water  stands  in  that  particular  well,  and  if  the  length  of  rod  which  has  been 
lowered  is  noted,  the  distance  from  the  surface  to  the  water  level  will  be 
found.  To  arrive  at  any  correct  estimate  of  the  true  ground- water  level,  a 
large  number  of  experiments  must  be  carried  out  simultaneously  in  the  wells 
over  a  considerable  area,  so  as  to  obviate  sources  of  error  arising  from  local 
conditions.  To  be  of  any  real  use,  such  observations  should  be  made  as 
frequently  as  possible  ;  those  from  which  Fodor  derives  his  conclusions 
having  been  made  every  week  in  a  large  number  of  adjoining  places,  the  series 
extending  over  a  period  of  several  years. 

Another  method,  given  by  Pettenkofer  for  the  determination  of  the  level 
of  well  water,  consists  in  tlie  use  of  a  large  float,  suspended  by  a  chain  passing 
over  a  pulley,  which  is  connected  with  a  counter-balance,  having  an  indicator 
attached  to  it,  which  marks  the  height  on  a  fixed  scale  which  has  been  pre- 
viously experimentally  graduated  for  the  length  of  the  chain. 

THE    TEMPEEATUEE    OF   THE    SOIL 

Different  soils  vary  very  considerably  in  the  extent  to  which  they  are 
capable  of  absorbing  heat,  this  depending  mainly  on  the  looseness  or  density 
of  the  particles  and  on  the  colour  of  the  soil ;  but,  in  most  places,  variations 
of  temperature  dependent  on  that  of  the  atmosphere  may  be  found  to  extend 
in  this  chmate  to  a  depth  of  about  sixty  feet,  and  even  deeper  in  other  por- 
tions of  the  globe.  These  variations  of  temperature  at  all  depths  do  not, 
however,  follow  directly  on  similar  fluctuations  in  the  atmospheric  tempera- 
ture, such  changes  being  delayed  longer  and  longer  in  the  lower  layers  of  the 
soil,  so  that  it  is  only  at  the  surface  that  there  is  any  immediate  correspon- 
dence between  the  temperatures  of  air  and  soil.  This  point  is  well  brought 
out  by  Fodor,  who  found  that  the  warming  and  cooling  of  the  deeper  layers 
was  much  slower  than  the  warming  and  cooling  of  the  atmosphere,  or  of 
the  superficial  layers  of  the  soil ;  his  observations  at  Buda-Pesth  giving 
the  following  results  : — 

The  average  maximum  temperature  at  a  de]Dth  of  ^  to  1  metre  was  found  in  August. 
,,  „  „  „  2  metres   was  found  in  September 

(and  August). 
„  „  „  „  4  metres  was  found  in  October  (and 

September). 
The  average  minimum  temperature  at  a  depth  of  ^  to  1  metre  was  generally  in  Feb- 
ruary and  January. 
„  „  „  „  2   metres  was  found   in  April;    in 

some  cases  in  March. 


328  HYGIENE 

He  also  found  that  the  greatest  range  of  temperature  was  noted 
in  the  superficial  layers ;  at  half  a  metre  below  the  surface  there  was  a 
variation  of  even  20°  C.  below  the  monthly  means  of  one  and  the  same 
year,  but  at  a  depth  of  four  metres  there  was  a  variation  of  5?,-°  only,  and 
in  some  places  of  hardly  more  than  8°.  The  temperature  at  this  depth 
was  very  uniform,  rising  and  falling  very  slowly,  seldom  varying  as  much 
as  half  a  degree  in  the  com-se  of  ten  days.  It  changed  most  rapidly 
in  the  spring,  and  when  it  reached  either  its  maximum  or  minimum  it 
usually  remained  constant  for  ten,  twenty,  or  even  more  days,  rising  to  the 
maximum  and  falling  to  the  minimum  at  an  average  rate  of  from  ^'„-°  to 
1-,)°  C.  every  ten  days.  In  the  upper  layers,  however,  the  variations  occur 
more  rapidly.  At  a  depth  of  two  metres  there  may  be  a  change  of  2^°  C. 
in  ten  days,  while  the  variations  are  still  greater  at  a  depth  of  one  metre  or 
less. 

Different  soils  vary  considerably  in  the  rapidity  with  which  they  are  in- 
fluenced by  the  atmospheric  temperature ;  that  is,  they  difter  in  the  rate  at 
which  a  rise  or  fall  of  temperature  takes  place  in  them.  The  temperature 
of  the  surface  soil  will  depend  greatly  on  whether  the  sun  shines  directly  on 
it,  as  in  this  case  a  higher  temperature  will  be  recorded  than  that  of  the 
atmosphere  above,  and  in  this  way  the  atmosphere  just  above  the  surface  may 
receive  much  of  its  heat  from  the  soil.  When,  on  the  other  hand,  the  sun's 
rays  no  longer  fall  on  the  soil,  it  readily  loses  heat,  and  may,  at  night,  possess 
a  lower  temperature  than  that  of  the  air.  When  this  takes  place,  the  moisture 
contained  in  the  air  condenses  upon  the  surface  in  the  form  of  dew. 

The  soil  temperature  below  the  surface  follows  even  great  variations  of 
air  temperature  but  sloAvly,  for  after  a  succession  of  warm  or  cold  days,  it 
needs  two  or  three  days  for  the  temperature,  at  a  depth  of  half  a  metre,  to 
begin  to  accommodate  itself  to  that  of  the  atmosphere.  Indeed,  a  change  of 
Ixom  twelve  to  fourteen,  or  even  more,  degrees  in  the  atmospheric  tempera- 
ture from  one  day  to  the  next  may  not  be  followed  by  a  change  of  even 
1°  G.  in  the  temperature  of  the  soil  half  a  metre  below  the  surface.  At  a 
depth  of  one  metre  the  changes  are  still  smaller,  while  at  two  or  four  metres' 
depth  the  increasing  or  decreasing  soil  temperature  moves  almost  in  a  straight 
line,  although  the  record  of  the  air  temperature  may  show  a  zigzag  curve. 

These  statements  receive  confirmation  from  the  observations  of  Lewis 
and  Cunningham  at  Calcutta,  who  found  that  fluctuations  in  temperature  in 
the  upper  layers  of  the  soil  follow  those  of  the  atmosphere  very  regularly, 
except  during  the  recurrence  of  rain,  when  this  correspondence  was  not  con- 
stant. Their  observations  were  taken  at  depths  of  three  feet  and  six  feet 
respectively.  The  fluctuations  in  the  temperature  of  the  lower  layer  were 
much  less  marked  and  sudden  than  in  the  more  superficial,  the  line  of  eleva- 
tion and  depression  following  a  long  gentle  curve.  They  found  also  that  the 
maxima  of  temperature  in  the  two  layers  approached  more  closely  than  the 
minima,  a  point  in  which  the  relations  of  temperature  corresponded  with 
those  of  carbonic  acid.  During  cold  weather  the  temperature  of  the  lower 
layers  considerably  exceeded  that  of  the  upper  one,  while  this  in  turn  was 
higher  than  that  of  the  atmosphere,  these  relations  being  exactly  reversed 
in  hot  weather,  when  the  temperature  of  the  upper  layer  was  the  highest, 
that  of  the  deeper  layer  of  the  soil  the  lowest. 

Different  geological  formations  vary  very  much  in  their  power  of  absorbing 
and  conducting  heat,  and  the  radiating  power  of  the  soil,  which  is  not  neces- 
sarily equal  to  its  power  of  absorption,  will  depend  somewhat  on  the  colour 
of  the  soil  and  also  on  the  kind  and  thickness  of  the  vegetation. 

That  the  temperature  of  the  soil  should  depend  to  a  certain  extent  on  its 


THE  INFLUENCE   OF  SOIL   ON  HEALTH 


329 


colour,  follows  from  the  well-known  fact  that  dark  substances  possess  the 
greatest  power  of  absorbing  heat  rays,  as  may  be  shown  by  the  oft-quoted 
experiment  of  placing  two  pieces  of  paper,  the  one  white  and  the  other 
black,  on  the  surface  of  snow  when  the  sun  is  shining  on  it,  when  it  will  be 
found  that  the  snow  melts  more  rapidly  under  the  black  paper  than  beneath 
the  white  piece. 

In  like  manner,  the  darker  the  soil,  the  more  rapidly  does  it  absorb  beat 
from  the  sun,  very  light-coloured  soils,  such  as  those  containing  much  chalk, 
heating  but  very  slowly.  Seeing  that  the  colour  of  the  darkest  soils  is  for 
the  most  part  due  to  the  products  of  decomposition  of  organic  substances,  it 
follows  that  the  warmest  soils  will  be  those  which  are  richest  in  humus. 
This  result  will  also  be  increased  to  a  certain  degree  where  decomposition  pro- 
cesses are  going  on  in  the  soil  because  of  the  heat  thus  produced,  while  also, 
since  on  a  warmer  soil  vegetation  will  be  more  luxuriant  and  growth  proceed 
at  a  greater  rate  than  elsewhere,  an  additional  appreciable  amount  of  heat 
will  result,  small  though  it  may  be  ;  it  having  been  proved  by  numerous 
observers  that  the  growth  of  plants  is  always  accompanied  by  a  rise  of  tem- 
perature, which,  again,  is  related  to  the  rapidity  of  their  vital  processes. 

The  following  table,  condensed  by  Lloyd  from  a  much  fuller  one  com- 
piled by  Liebenberg,  of  Halle,  shows  both  the  rapidity  with  which  heat  is 
gained  by  various  kinds  of  soil  and  also  the  rate  at  which  it  penetrates 

beneath  the  surface  : — 

Gain  of  Heat  by  Soils 


Original 
temp. 

After 

1  hour 

After  1  hour 

After  2  hours 

2  cm. 

5  cm. 

2  cm. 

5  cm. 

2  cm. 

5  cm. 

Lime  sand 

21°  C. 

29°  C. 

27-5°  C. 

32°  C. 

31-5°  C. 

36-5°  C. 

37°  C. 

Tertiary  clay     . 

21 

300 

27-5 

33-0 

30-0 

36-3 

35-0 

Tertiary  sand    . 

21 

30-0 

28-0 

33-5 

32-5 

37-5 

36-5 

Marl . 

21 

31-0 

28-5 

34-5 

32-5 

39-0 

37-5 

Meadow  loam   . 

21 

32-0 

27-5 

37-0 

36-0 

40-5 

38-5 

Eich  loam 

21 

32-5 

29-0 

36-0 

34-0 

41-5 

39-5 

Basalt  soil 

21 

33-0 

28-5 

35-0 

33-0 

42-0 

38-0 

Water 

21 

26-0 

26-0 

29-5 

29-5 

31-0 

31-0 

This  table  shows  not  only  that  sand  becomes  warmed  throughout  more 
rapidly  than  clay,  but  also,  as  stated  above,  that  the  richer  a  soil  is  in  organic 
matter,  the  greater  the  power  it  possesses  of  absorbing  heat.  It  further  shows 
that  the  temperature  of  water  increases  but  slowly,  which  probably  accounts 
tor  the  fact  that  soils  containing  much  water  are  colder  than  those  which  are 
comparatively  dry  ;  and  indeed  it  has  been  established  by  observation  that  the 
damper  the  soil,  the  slower  it  is  to  become  warm,  which  accounts  for  the 
•differing  behaviour,  as  shown  in  the  table,  between  sandy  soils,  which  are  dry 
and  warm,  and  clay,  which  retains  a  large  amount  of  moisture.  Not  only  do 
clay  soils  warm  slowly,  but  they  also  rapidly  lose  their  heat,  whereas  sandy 
soils  on  the  contrary  retain  their  warmth  for  a  considerably  longer  time. 
The  results  of  some  experiments  by  Liebenberg  are  shown  in  the  following 
table  : — ■ 

Loss  of  Heat  by  Soils 


Nature  of  soil 

Original  temp. 

After  4  hour 

After  1  hour 

After  2  hours 

Coarse  sand 

41-25°  C. 

29-75°  C. 

24-25°  C. 

19-75°  C. 

Fine  sand 

41-75 

28-25 

23-25 

18-75 

Marls 

40-00 

27-50 

23-00 

18-50 

Loams 

40-00 

27-00 

22-00 

18-00 

Clay          .         .     ■     . 

89-50 

26-00 

21-50 

18-00 

830  EYGIEXE 

The  following  table  by  Schilbler  shows  the  results  of  his  observations  on 

the  power  possessed  by  various  soils  of  retaining  heat,  a  power  dependent 

partly  on  the  physical  properties  and  partly  on  the  chemical  composition  of 

the  soil  : — 

Power  of  retaining  Heat,  100  beiyig  assumed  as  the  Standard 


Sand,  with  some  limestone        .         .  100 

Pure  sand  , 95'6 

Light  clay 76-9 

Gypsum     ,         .         .         .         .         .  72-2 

Heavy  clay         .....  71'1 


Clayey  earth C8'4 

Pure  clay 06*7 

Fine  chalk 61-8 

Humus 49 


Usually  radiation  takes  place  more  rapidly  than  absorption,  particularly 
where  herbage  is  abundant,  so  that  soils  cool  more  rapidly  than  they  heat. 
Jourdanet  cites  a  remarkable  instance  of  this  which  was  noticed  in  some  of 
the  marshes  in  Mexico,  which  cool  so  rapidly  at  night  that  the  evolution  of 
malaria  is  prevented,  the  marsh  consequently  not  being  dangerous  at  night. 
On  one  occasion  when  the  air  temperature  at  a  height  of  sixteen  feet  from 
the  ground  was  58°  F.,  that  of  the  marsh  at  the  ground  level  was  only  32°  F. 
The  effect  of  herbage  on  both  the  radiating  and  absorbing  power  of  the  soil 
is  often  very  great,  a  difference  of  as  much  as  30°  F.  having  been  recorded  in 
a  tropical  climate  between  the  temperature  of  a  naked  rock  and  an  adjoining 
one  which  was  covered  with  grass. 

The  effect  of  soil  temperature  on  disease  was  first  described  by  Delbruck, 
who  called  attention  to  its  importance  in  connection  with  an  epidemic  of 
cholera  at  Halle  in  1867  which  appeared  to  be  associated  with  a  maximum 
soil  temperature  combined  with  a  certain  degree  of  soil  moisture.  It  doubt- 
less also  influences  the  spread  of  malaria,  while  recently  Ballard  has  demon- 
strated its  important  relations  with  the  occurrence  of  summer  diarrhoea, 
Pfeiffer,  Kiichenmeister,  Fleck,  and  Fodor  have  also  investigated  this  subject. 

Estimation  of  Soil  Tempebatuke 

The  method  by  which  their  observations  on  the  temperature  of  the 
soil  was  carried  out  is  thus  described  by  Lewis  and  Cunningham.  A 
shallow  shaft  or  well  of  sufficient  capacity  to  allow  of  easy  entrance  was 
sunk  in  the  soil  to  a  depth  of  slightly  over  six  feet,  and  was  lined  with  bricks 
and  mortar.  An  opening  was  left  in  the  floor  to  allow  of  di'ainage  of  any  sur- 
face water  which  might  obtain  entrance,  and  two  openings  were  left  in  the 
brickwork  of  one  side  of  the  shaft  at  depths  of  three  and  six  feet  respectively 
leading  into  wide  tubes  of  perforated  zinc,  which  penetrated  the  soil  hori- 
zontally from  the  outer  surface  of  the  brickwork  and  terminated  in  open 
extremities  in  the  earth.  These  tubes  were  of  sufficient  diameter  to  allow  of 
a  narrow  board,  carrying  the  thermometers,  being  pushed  into  them.  The- 
thermometer  board  had  a  wooden  plug  and  handle  which  fitted  into  the 
mouth  of  the  tube,  whilst  the  opening  in  the  brickwork  was  closed  by  an 
accurately  adjusted  wooden  cover,  and  further  secured  by  being  coated 
externally  with  moist  clay. 

A  thick  wooden  lid,  covered  with  a  layer  of  turf,  closed  the  mouth  of  the 
shaft,  and  the  entrance  of  rain  or  access  of  sun  to  the  cover  was  prevented 
by  a  thatch  roof  about  five  feet  from  the  ground. 

Observations  were  made  at  the  same  hour  every  day,  and  the  thermo- 
meters immediately  returned  to  their  places  in  the  perforated  zinc  tubes  let 
into  the  earth,  care  being  taken,  before  returning  them,  to  raise  the  temperature 
of  the  minimum,  and  to  depress  that  of  the  maximum  instrument  considerably 
above  and  below  the  temperature  of  the  soil. 


.     THE  INFLUENCE   OF  SOIL   ON  HEALTH  331 

Fodor  advises  that  the  thermometers  should  be  placed  in  a  two-inch  tin 
tube,  the  interval  between  the  thermometer  and  the  casing  being  filled  in 
with  fine  sand. 


DISEASES   ATTRIBUTED   TO   CONDITIONS   OP   THE    SOIL 

The  permeability  of  the  soil,  its  composition  and  that  of  the  ground  air, 
the  amount  of  heat  and  moisture  present,  and  the  variations  in  level  of  the 
subsoil  water,  have  been  found  by  numerous  observers  to  bear  important  re- 
lations to  many  of  the  diseases  which  afflict  mankind,  while  the  lower  animals 
are  also,  though  perhaps  in  less  degree,  liable  to  suffer  from  like  causes. 

Coincident  with  the  disappearance  of  oxygen  from  the  ground  atmosphere 
an  equivalent  amount  of  carbon  dioxide  is  produced,  which  when  the  pressure 
of  the  air  above  ground  is  increased,  or  when  the  temperature  is  lowered, 
penetrates  the  soil.  This  drives  out  before  it  the  ground  air,  which  may  thus 
enter  the  cellars  and  basements  of  houses,  from  which  it  will  probably  ascend, 
through  the  influence  of  convection  currents,  to  the  upper  stories.  A  similar 
effect  has  been  shown  to  occur  in  consequence  of  heavy  rains,  the  water 
filHng  up  the  interstices  of  the  soil  near  the  surface,  and  so  forcing  down  the 
gases  in  the  soil,  which  will  then  escape  at  places  where  the  ground  is  dry,  as 
under  buildings,  this  effect  being  the  more  likely  to  happen  the  greater  the 
porosity  of  the  soil. 

Many  basement  dwellings  extend  from  three  to  ten  feet  below  the  surface 
of  the  ground,  and  seeing  that  at  a  depth  of  thirteen  feet  (four  metres)  the 
amount  of  oxygen  present  in  the  air  entering  them  from  below  may  be  from 
one-third  to  one-half  of  the  normal  percentage,  the  carbon  dioxide  is  in- 
creased inversely  as  the  amount  of  oxygen  present.  Accordingly,  it  is  evident 
that  the  danger  incurred  by  the  inhabitants  of  such  dwellings  may  be  very 
much  the  reverse  of  imaginary,  particularly  if  the  soil  be  much  polluted  with 
organic  matter.  This  will  be  the  more  rea.dily  appreciated  when  we  remember 
that  the  soil,  and  so  the  ground  air  also,  teems  with  micro-organisms  of 
various  kinds,  some  of  a  pathogenic  nature.  These,  when  the  soil  is  dry, 
being  carried  in  various  directions  by  the  currents  of  ground  air,  and  finding 
exit  at  the  surface,  may  affect  the  atmosphere  of  the  immediate  or  of  con- 
tiguous localities,  or  may  be  carried  to  considerable  distances  from  the  spot 
where  they  originated.  If,  on  the  other  hand,  such  diffusion  is  prevented  by 
the  effects  of  the  pressure  or  temperature  of  the  air  above,  or  by  a  blocking 
of  the  upper  layer  of  the  soil  by  water,  they  will  tend  to  be  carried  directly 
into  buildings  along  vdth  the  impure  ground  air. 

In  spring  and  early  summer,  however,  the  ground  being  cooler  than  the 
air  above,  the  ground  air,  being  in  consequence  denser  and  heavier,  is  not  so 
easily  displaced  as  at  other  seasons  of  the  year.  In  autumn,  on  the  contrary, 
the  ground  air  is  displaced  with  greater  ease,  and  so  is  more  likely  to  be  forced 
out  from  the  interstices  of  the  soil  into  the  atmosphere  above.  These  facts 
would  afford  an  explanation  of  the  comparatively  slight  prevalence,  in  spring 
and  early  summer,  and  greater  prevalence  in  autumn,  of  certain  epidemic 
infectious  diseases  which  may  be  thought  to  depend  on  movements  of  the 
ground  air.  Similar  conditions  may,  perhaps,  explain  also  the  greater  Likeli- 
hood of  infection  at  night,  which  is  believed  to  occur  in  connection  with  such 
diseases  as  malaria  and  yellow  fever  (Eohe). 

The  level  of  the  ground  water  and  the  amount  of  moisture  in  the  soil 
above  it,  have  been  shown  to  have  a  considerable  influence  on  the  extent  of  the 
putrefactive  processes  going  on  in  the  soil,  and  these  in  towns  will  influence- 


332  HYGIENE 

the  composition  of  air  and  drinldng  water,  and  so  directly  or  indirectly  the 
health  of  the  population  of  the  district.  Thus  dampness  of  the  surface  will 
cause  a  cold  soil  and  a  misty  air,  and  as  a  result,  perhaps,  encourage  such 
diseases  as  paroxysmal  fevers,  rheumatism,  neuralgia,  and  various  lung 
affections.  On  the  other  hand,  certain  dry  and  apparently  pure  soils,  which 
would  usually  he  considered  healthy,  are  apt  to  cause  malaria,  the  reason 
for  which  is  not  very  evident  ;  it  may,  however,  be  explicable  *in  the  manner 
already  suggested,  that  the  porosity  of  the  soil  allows  the  transference  of 
contaminated  air  from  considerable  distances. 

In  several  of  the  diseases  held  to  be  related  to  telluric  conditions,  recent 
researches  have  shown  that  definite  micro-organisms  are  invariably  found 
in  the  blood  or  tissues  of  affected  persons  or  animals,  although  the  exact  rdle 
played  by  such  microphytic  forms  in  the  causation  of  disease  has  not  been 
in  most  instances  at  all  certainly  determined.  It  is,  therefore,  highly  desir- 
able, not  only  that  the  life  history  of  these  bacteria  should  be  studied  in  the 
body  of  their  host,  but  also  that  diligent  search  should  be  made  for  them 
among  the  numerous  micro-organisms  which  are  always  to  be  foimd  in  ordinary 
surface  soil,  so  that  the  relations  of  environment  to  their  destruction  or  special 
multiplication  at  any  given  time  and  place  may  be  as  nearly  as  possible 
determined.  Some  observers  have  thought  that  under  certain  circumstances 
bacteria  ordinarily  harmless  may  take  on  pathogenic  properties,  and  although 
the  weight  of  evidence  may  be  against  this,  it  seems  hardly  possible,  on  any 
other  assumption,  to  explain  the  sudden  appearance  of  a  given  disease  in 
absence  of  all  apparent  relation  to  pre-existing  disease  of  like  sort,  or  to  ex- 
plain the  various  types  presented  by  one  and  the  same  disease  in  different 
epidemics.  As  Buchanan  says,  'Looking  to  the  prodigious  part  that  bacterial 
life  plays  in  the  economy  of  nature,  it  is  hardly  too  much  to  expect  that 
morbific  bacteria  may  come  hereafter  to  be  known,  not  merely  as  producing 
disease  under  certain  conditions,  but  as  having,  under  other  conditions,  many 
other  functions  in  that  economy.'  '  Whether,  and  if  so  where,  and  under 
what  conditions,  the  bacilli  found  in  tubercle,  for  instance,  exist  elsewhere 
in  some  harmless  state,  and  by  what  change  of  conditions  they  can  become 
morbific,  are  problems  of  the  highest  importance.'  We  know  that  under 
conditions  of  artificial  cultivation,  which  have  been  carefully  studied  of  late,  it 
is  possible  to  so  reduce  the  virulence  of  many  pathogenic  bacteria  that  ulti- 
mately their  injection  into  the  living  body  is  practically  without  appreciable 
effect,  and  fails  even  in  conferring  immunity  against  the  subsequent  action 
of  more  potent  cultures  ;  is  it  then  beyond  the  region  of  possibility  that  such 
organisms  under  certain  other  conditions  may  once  more  regain  their  original 
pathogenic  properties  after  a  temporary  stage  of  suspended  function,  in  a 
reverse  manner  to  that  in  which  these  properties  were  originally  lost ;  that 
such  changes  should  be  capable  of  occurring  in  the  interstices  of  the  soil  as 
well  as  in  the  culture-tube  of  the  bacteriologist  ? 

Investigations  on  these  Hnes  promise  not  only  information  as  to  the  pro- 
duction of  disease,  but  knowledge  also  of  methods  of  preventing  disease,  which 
is  the  primary  aim  of  sanitary  science.  Much  has  already  been  done,  but 
much  still  remains  to  be  done  before  what  we  think  we  know  can  be  con- 
sidered to  possess  firm  basis  of  fact.  In  the  following  pages  are  given  the 
results  of  research  up  to  the  present  time  on  the  relation  to  soil-conditions 
of  certain  diseases ;  but  unfortunately  the  subject  is  still  to  a  considerable 
extent  veiled  in  obscurity,  so  that,  even  as  regards  not  a  few  diseases  in  which 
such  connection  would  appear  most  indisputable,  we  are  as  far  as  ever  from 
a  knowledge  of  hoAV  best  to  combat  the  malign  influences  that  confront  us. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  333 


Typhoid  ok  Enteeic  Fever 

Althougli  until  comparatively  recent  years  thia  disease  was  confounded 
with  typhus,  we  have  evidence  that  it  has  asserted  its  presence  in  more  or 
less  virulent  forms  for  at  least  the  last  two  hundred  years,  Baglivi  and 
Lancisi  having  described  cases,  apparently  of  this  disease,  which  occurred  at 
Eome  at  the  end  of  the  seventeenth  century,  but  which,  however,  they 
believed  to  be  a  form  of  ague.  It  is  also  of  interest  that  Dr.  Norman  Moore 
has  proved  from  the  memoranda  of  Dr.  Mayerne,  physician  to  James  I.,  that 
the  disease  of  which  Henry,  Prince  of  Wales,  died  in  1612  was  enteric  fever. 

The  chief  credit,  at  any  rate  in  this  country,  in  demonstrating  the  differ- 
ences between  typhoid  and  typhus  fevers  is  undoubtedly  due  to  Dr.  A.  P. 
Stewart,  who,  as  the  result  of  his  observations,  came  to  the  conclusion  that 
the  differences  between  the  two  diseases  were  '  so  marked  as  to  defy  miscon- 
ception, and  to  enable  the  observer  to  form  with  the  utmost  precision  the 
diagnosis  of  the  nature  of  the  disease  and  the  lesions  to  be  revealed  by  dis- 
section '  (1840).  Strother,  however,  in  1729,  first  gave  a  description  of  the 
anatomical  characters  of  the  disease,  which,  he  says,  is  a  '  symptomatical 
fever  arising  from  an  inflammation,  or  an  ulcer,  fixed  on  some  of  the 
bowels.'  The  fact  of  this  disease  affecting  specially  the  bowels  obviously  gives 
special  opportunity  for  fouling  tbe  earth,  and  so  for  the  passing  on  of  the 
disease  to  other  persons. 

In  certain  placestyphoid  appears  to  be  endemic,  but  elsewhere  its  prevalence 
has  been  proved  for  the  most  part  to  be  largely  due  to  the  movements  and  inter- 
course of  human  beings,  numerous  instances  having  been  placed  on  record  in 
which  outbreaks  occurring  in  localities  previously  entirely  free  from  the  disease 
have  been  traced  to  the  arrival  of  a  patient  already  suffering  from  enteric 
fever,  opportunity  having  been  thus  afforded  for  specific  contamination  of 
the  soil.  Murchison  and  others  have,  indeed,  affirmed  the  disease  to  be  capable 
of  arising  de  novo  when  surrounding  conditions  were  favourable  thereto,  sup- 
porting their  view  with  numbers  of  cases  in  which  the  most  exhaustive  inquiry 
had  failed  to  elicit  any  trace  of  a  pre-existent  human  case.  This  theory,  how- 
ever, finds  little  acceptance  at  the  present  day,  and  later  writers  have  attempted 
to  explain  Murchison's  cases  on  the  supposition  that  the  bacillus  which  is 
believed  to  be  the  exciting  cause  of  the  disease  is  a  vegetable  parasite  having 
an  existence  independent  of  the  human  subject,  capable  of  completing  its  life- 
cycle,  and  of  reproducing  itself,  if  not  in  some  other  animal  body,  in  the  earth 
or  atmosphere.  If  this  be  so,  one  may  thus  account  not  only  for  those  cases 
occurring  in  this  country  which  it  has  been  impossible  to  trace  to  infection  from 
one  person  to  another,  but  also  for  the  fact  that  travellers  have  been  stricken 
down  with  this  disease  in  tropical  countries  believed  to  be  entirely  uninhabited. 

For  the  most  part,  however,  typhoid  undoubtedly  spreads  indirectly 
through  the  stools  from  one  or  more  specific  cases  of  the  disease,  infecting 
drains,  sewers,  cesspools,  or  the  soil  itself,  by  which  means  the  drinking 
water,  air,  or  food  become  contaminated,  and  thus  secure  propagation  of  the 
malady  in  various  directions  ;  the  water,  of  course,  usually  becoming  infected 
from  having  passed  through  already  polluted  earth.  By  the  admixture  of 
such  water  with  milk,  or  from  dairy  utensils  having  been  washed  out  with  it, 
we  have  other  means  by  which  the  disease  may  secure  further  victims. 

For  the  system  to  be  affected  with  typhoid,  the  essential  cause  of  the 
malady  must  doubtless  gain  access  to  the  alimentary  canal,  a  possible  way 
being  that  the  dust  of  dried  excreta  may  be  carried  in  the  air  to  the  mouth, 
and  then  swallowed  with  the  sahva ;   but  the  more  frequent  channel  is 


334  HYGIENE 

undoubtedly  by  the  ingestion  of  di-iuk  and  food.  So  great  a  mass  of  evidence 
has  been  collected  on  this  point  that  the  fact  has  well-nigh  been  lost  sight 
of  that  in  many  cases  the  diinking  water,  for  instance,  is  only  the  vehicle,  the 
soil  itself  being  the  situation  not  only  from  which  the  poison  is  immediately 
derived,  but  one  in  which  it  is  capable  of  lying  dormant  for  an  indefinite 
period.  A  case  which  illustrates  this  point  is  related  by  Von  Giett.  A  man 
who  had  acquired  enteric  fever  elsewhere  brought  it  to  a  village.  His  eva- 
cuations were  buried  in  a  dung-heap.  Some  weeks  later  five  persons  engaged 
in  removing  some  of  the  dung  were  attacked  by  the  disease  ;  their  discharges 
were  sunk  deep  in  the  heap.  At  the  end  of  nine  months  it  was  completely 
cleared  out  by  two  workmen,  one  of  whom  fell  ill  of  enteric  fever  and  died. 

Murchison  also  states  that  he  has  seen  single  cases  of  enteric  fever 
arising  in  the  same  house  again  and  again  at  intervals  of  a  year  or  longer. 
In  such  a  ease  it  is  obviously  unnecessary  to  suppose  that  on  each  occasion 
the  specific  poison  had  been  brought  afresh  to  the  place,  itbemg  much  more 
hkely  that  the  germs  of  the  disease  had  been  present  during  the  whole 
period,  and  had  from  time  to  time  been  roused  to  increased  activity  by  the 
changing  influence  of  their  environment.  Several  instances  also  have  been 
recorded  in  which  boys  who  had  watched  the  clearing-out  of  the  soil 
around  old  and  imperfect  drains  had  shortly  afterwards  been  smitten  down 
with  the  disease. 

In  many  country  villages  typhoid  has  been  known  to  break  out  every 
autumn,  although  no  sanitary  defect  could  be  discovered.  In  such  cases  it 
is  probable  that  a  large  area  of  the  soil  is  polluted,  and  thus,  particularly 
where  the  water-supply  is  derived  from  surface-wells,  it  is  impossible  to 
secure  immunity  from  the  disease  unless  an  entirely  different  source  of 
water  for  drinking  purposes  be  provided. 

An  instance  of  an  outbreak  of  enteric  fever,  traced  to  the  contammation 
of  milk  with  such  a  water-supply,  is  seen  in  Dr.  Ballard's  report  of  his  inves- 
tigations at  Armley,  near  Leeds,  in  the  summer  of  1872.  He  found  that  aU 
the  early  cases,  with  one  exception,  had  been  supplied  with  milk  from  the 
same  dairy,  which  had  been  mixed  with  water  obtained  from  a  pump  on  the 
premises.  He  found,  moreover,  that  about  a  month  before  the  epidemic 
appeared  the  dairyman  had  himself  been  ill  with  typhoid  fever,  and  that  his 
excreta  had  been  deposited  in  a  privy,  the  drainage  from  which  escaped  into 
the  soil.  From  thence  faecal  matter  had  apparently  been  washed  by  heavy 
rains  occurring  at  the  time,  into  the  well  from  which  the  pump  was  fed ; 
this  supposition  being  borne  out  by  the  fact  that  at  the  bottom  of  the  well  a 
layer  of  filthy  mud  was  found  from  which  bubbles  of  gas  escaped  when  it 
Avas  disturbed,  while  from  the  sides  of  the  well  next  the  privy  a  similar  black 
material  was  found  to  be  oozing. 

The  prevalence  of  typhoid  fever  is  markedly  affected  by  seasonal  and  cli- 
matic influences,  the  greater  number  of  cases  in  this  country  occurring  in  the 
autumn,  and  being,  in  particular  locaHties,  especially  large  when  the  preceding 
summer  has  been  hot  and  dry,  while,  on  the  other  hand,  if  the  summer  has 
been  damp  and  cold,  the  disease  will  not  attain  so  high  a  point.  The  statistics 
of  the  London  Fever  Hospital  for  the  years  1848-1870  inclusive  show  that 
the  number  of  admissions  was  greatest  each  year  from  August  to  November, 
while  it  w  is  least  in  April  and  May.  Buchan  and  Mitchell,  dealing  with 
enteric  fever  deaths,  state  that,  taking  the  average  of  a  large  number  of  years, 
the  maximum  point  is  reached  in  the  last  week  in  October,  while  the  disease 
does  not  fall  below  its  average  until  the  last  week  in  February,  attaining  its 
absolute  minimum  from  the  middle  of  May  to  the  end  of  June. 

Observations  made  on  this  subject  in  Berlin  and  Basle  also   show   a 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  335 

similar  relation  between  intense  summer  heat  and  excessive  prevalence  of 
typhoid,  the  maximum  amount  of  fever  in  these  places  also  occurring  two  or 
three  months  later  than  the  maximum  temperature,  while  at  Munich  the  re- 
tardation is  more  marked,  the  greatest  number  of  deaths  occurring  in 
February.  Fodor  shows  that  at  Buda-Pesth  the  number  of  deaths  usually 
rises  in  winter  and  spring,  the  severest  epidemic  that  has  visited  that  place — 
that  of  1864-65 — having  reached  its  maximum  in  January,  and  from  these 
facts  he  argues  that,  since  the  typhoid  curve  shows  no  relation  to  those  of 
•either  temperature  or  of  CO2  production,  the  prevalence  of  the  disease  is  not 
dependent  on  putrefactive  processes  going  on  in  the  superficial  layers  of  the 
soil.  These  results  are  arrived  at  by  comparing  the  death  curve  with  the 
condition  of  soil  at  the  time  of  infection,  or  at  a  period  of  from  four  to  five 
weeks  previous  to  the  termination  of  the  disease,  thus  allowing  for  (1)  incu- 
bation about  two  weeks,  though  it  is  often  much  shorter — Zehndes,  for 
instance,  stating  that  in  pregnancy  it  may  only  be  from  twenty-four  to  forty- 
eight  hours  ;  and  for  (2)  period  of  illness  preceding  death,  which  Murchison 
found,  as  an  average  of  112  cases,  to  be  as  nearly  as  possible  27|  days. 

Although  no  pronounced  relation  could  be  found  between  the  death  rate 
and  the  temperature  or  putrefactive  activity  of  the  soil,  Fodor  has  demon- 
strated an  apparent  close  connection  between  the  typhoid  curve  and  one 
representing  variations  in  the  level  of  the  Danube,  both  these  curves,  almost 
without  exception,  rising  and  falling  together.  Thus  at  the  begining  of  1872, 
both  of  these  curves  rose  simultaneously,  attained  their  acme  in  the  middle  of 
the  year,  and  then  both  fell  off  in  a  like  manner.  In  this  connection  it  must 
be  remembered  that  the  level  of  the  Danube  exerts  a  very  regular  influence 
■on  the  ground-water  level  throughout  the  greater  part  of  the  town,  and  thus 
it  would  appear  that  in  Buda-Pesth  typhoid  is  most  commonly  related  to  a 
rising  level  of  the  water  in  the  soil.  In  Munich,  where  Buhl  applied  the 
observations  of  Pettenkofer  on  cholera  to  the  incidence  of  typhoid,  and  in 
Berlin,  on  the  other  hand,  the  reverse  phenomenon  has  been  recorded,  the 
disease  in  both  places  increasing  as  the  ground  water  falls.  This  latter  state 
of  things  has  been  referred  to  a  more  active  decomposition  of  organic  material 
in  the  more  superficial  and  polluted  layers  of  the  soil,  following  on  the  abstrac- 
tion of  a  certain  amount  of  water  from  the  earth,  and  possibly  this  explana- 
tion may  be  correct  as  regards  Berlin,  where  outbreaks  most  commonly  occur 
in  autumn.  In  Buda-Pesth,  however,  as  already  stated,  the  disease  is  usually 
more  prevalent  in  winter  and  spring,  and  seeing  that  there  is  often  so  close 
a  connection  of  epidemic  enteric  fever  with  variations  in  level  of  the  ground 
water,  we  may  perhaps  infer  that  it  is  there  influenced  to  a  certain  extent  by 
processes  going  on  in  the  deeper  layers  of  the  soil,  those  layers  indeed  in 
which  the  rise  or  fall  of  the  ground  water  is  felt. 

Liebermeister  and  Buchanan,  with  considerable  reason,  have  supposed 
that  soil-water  observations  simply  illustrate  the  commimication  of  the  disease 
by  means  of  drinking  water  ;  the  water  of  surface  wells  being  generally  more 
impure  when  the  level  of  the  soil  water  is  persistently  low,  when  also  there 
will  be  more  likelihood  of  noxious  matter  accumulating  in  the  stagnant  water 
in  the  soil. 

Eainfall,  and  the  consequent  wetting  of  the  superficial  layers  of  the  soil, 
has  obviously  no  influence  in  regulating  the  spread  of  typhoid,  since  the 
disease  may  prevail  to  an  equal  extent  whether  the  surface  of  the  earth  is  dry 
or  the  reverse,  and  this  even  when  the  wettmg  of  the  upper  stratum  is 
markedly  related  to  the  amount  of  the  rainfall. 

Seeing,  then,  that  at  Buda-Pesth  at  any  rate,  and  perhaps  at  Munich,  there 
is  proof  of  a  close  relation  between  the  extent  to  which  typhoid  prevails,  and 


336  HYGIENE 

the  variations  in  level  of  the  ground  water,  but  to  no  other  meteorological 
state,  it  would  be  well  to  compare  the  conditions  in  Buda-Pesth  with  those 
in  other  cities  in  which  this  subject  has  been  investigated,  the  following 
points  being  those  which  appear  specially  worthy  of  note  : — 

1.  That  the  groimd  water  in  that  town  hes  for  the  most  part  near  to  the 
surface,  especially  in  those  parts  which  have  suli'ered  most  fi'om  typhoid. 

2.  That  the  variations  of  level  are  very  small,  and  that  they  are  regulated 
by  the  level  of  the  Danube. 

3.  That  the  horizontal  movement  of  the  ground  water  is  very  slow  ;  and, 

4.  That,  in  consequence  of  this  movement  being  particularly  slow,  the 
water  stagnates  in  the  polluted  soil  in  those  parts  of  the  town  which  suffer 
most  severely  when  the  Danube  rises. 

At  present,  however,  but  little  is  certainly  known  as  to  the  influence  of 
telluric  conditions  on  the  prevalence  of  this  disease,  and  further  research  is 
needed  before  any  dogmatic  statement  can  be  made  ;  but  notwithstanding 
the  obscurity  which  still  hangs  over  this  subject — an  obscurity  increased  by 
the  fact  that  Buhl's  law,  or  the  converse  proposition  as  enunciated  by  Fodor, 
is,  as  it  seems,  applicable  to  certain  places  only,  having  no  relevancy  for 
others — no  one  can  deny  the  importance  of  the  soil  as  the  breeding  place  of 
the  typhoid  poison.  No  doubt,  as  Hirsch  says,  tj'phoid  may  develop  under 
circumstances  where  any  influence  of  the  soil  is  not  only  highly  improbable 
but  even  excluded  as  an  etiological  factor  altogether,  as  in  epidemics  in 
rooms.  But  those  cases  are  by  no  means  in  contradiction  of  the  theory  ; 
they  serve  rather  to  corroborate  it,  inasmuch  as  the  same  conditions  that 
cause  or  assist  the  typhoid  poison  to  ripen  or  acquire  potency  in  the  soil  may 
be  met  with  also  outside  the  soil.  As  Lindwurm  very  justly  says,  '  What 
the  soil  is  on  a  large  scale,  the  same  on  a  small  scale  are  also  the  floors 
of  rooms,  the  walls  of  houses,  the  drains  of  privies  and  the  like.  Just  as  it 
matures  at  some  depth  in  the  ground,  so  also  may  the  typhoid  germ  obtain 
the  necessary  conditions  for  its  growth  in  a  seam  or  cleft  in  the  flooring  of  a 
room,  or  in  the  loosened  mortar  and  sand  between  stones  and  slabs.' 

The  Typhoid  Bacillus 

To  Eberth,  Gaffli-y,  Klebs,  and  Koch  we  owe  the  discovery  of  a  specific 
microbe  which  is  at  the  present  time  believed  to  be  the  essential  cause  of 
typhoid  fever.  Prior  to  the  publication  of  their  researches,  Eecklinghausen, 
Klein,  Browicz,  Fischel,  and  other  observers  had  described  colonies  of  micro- 
cocci which  they  had  found  in  the  mucous  membrane  of  the  intestine,  in  the 
kidneys,  the  spleen,  and  even  in  the  muscular  tissue  of  the  heart,  but  the 
presence  of  these  cocci  was  probably  merely  accidental  and  had  no  relation  to 
the  occurrence  of  the  disease. 

There  is  great  difficulty  in  obtaining  the  specific  bacillus  from  typhoid 
stools,  because  of  the  large  number  of  other  micro-organisms  which  are 
present,  and  which  in  the  course  of  their  growth  liquefy  the  gelatine. 
Chantenesse  and  Widel,  however,  have  shown  that  if  trichloride  of  iodine 
be  added  to  the  gelatine  in  which  the  cultivation  is  made,  the  growth  of  the 
ordinary  putrefactive  organisms  is  aborted  while  the  typhoid  bacillus  is  un- 
affected. A  similar  result  may  be  obtained  by  keeping  the  growth  at  a 
temperature  of  about  45°  C,  at  which  the  typhoid  bacillus  alone  is  capable 
of  existing,  or  by  adding  to  the  culture  medium  a  small  quantity  of  carbolic 
acid. 

By  adopting  one  or  other  of  these  methods,  the  presence  of  the  typhoid 
bacillus  has  been  detected  in  water  known  to  have  caused  an  outbreak  of 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  337 

fever  even  when  chemical  analysis  failed  to  indicate  any  serious  organic 
contamination.  In  an  epidemic  investigated  by  Bonner,  he  was  unable  to 
find  the  bacillus  in  the  water  of  a  well  supposed  to  have  caused  the  outbreak, 
but  found  it  abundantly  in  the  soil  in  the  neighbourhood  of  the  well. 

Inoculation  experiments  with  the  bacillus  on  animals  have  not  up  to  the 
present  met  with  much  success. 

'  The  prophylactic  measures  against  the  spread  of  typhoid  fever  comprise 
isolation  of  the  sick,  prompt  disinfection  and  careful  disposal  of  the  dis- 
charges, and  cleanliness  in  the  widest  sense.  The  water  and  food  supplies 
must  be  carefully  guarded  against  contamination  with  the  poison,  and  all 
decomposing  animal  matter  and  excreta  must  be  removed  from  the  immediate 
vicinity  of  dwellings.  The  requisites  for  prevention  may  be  summed  up  as 
pure  air,  pure  water,  uncontaminated  food,  and  a  clean  soil.' 

DiPHTHEEIA 

Although  not  long  since  mainly  prevalent  in  rural  districts,  diphtheria 
is  a  disease  which  of  late  years  has  unfortunately  become  exceedingly  pre- 
valent in  towns  as  well,  London  now  showing  a  greater  rate  of  mortality 
from  this  disease  than  any  other  district  in  England  and  Wales.  It  was  not 
until  1855  that  it  came  at  all  prominently  into  notice,  in  which  year,  and 
those  immediately  following,  numerous  outbreaks  occurred  in  various  parts  of 
England,  since  when,  to  quote  Dr.  Thorne  Thome's  words,  it  has  been  an 
almost  continuous  and,  generally  speaking,  an  increasing  cause  of  death 
amongst  us.  This  is  strikingly  shown  by  the  fact  that  within  the  last  twenty 
years  the  total  annual  number  of  deaths  from  diphtheria  in  England  and 
Wales  has  more  than  doubled,  while  in  London  it  has  more  than  trebled  in 
the  same  length  of  time.  It  is  of  course  possible,  however,  that  the  previous 
excessive  prevalence  in  rural  districts  may  be  only  masked  at  the  present 
time  by  some  cause  common  to  large  centres  of  population,  such  as  personal 
contagion. 

In  1859  the  Medical  Department  of  the  Privy  Council  undertook  a  some- 
what extensive  inquiry  into  the  subject,  as  the  result  of  which  it  appeared 
that  the  disease  prevailed  for  the  most  part,  although  not  entirely,  in  damp 
and  marshy  situations  and  on  cold  wet  clay  soils.  Dr.  Greenhow  also  reported 
that  associated  with  it  he  had  found  a  marked  prevalence  of  certain  diseases 
affecting  the  nasal  and  buccal  mucous  membranes  of  certain  of  the  domestic 
animals,  such  as  cattle  and  horses,  although  he  did  not  succeed  in  tracing 
any  definite  connection  between  such  affections  and  the  disease  in  human 
beings.  In  these  observations  he  paved  the  way  for  the  recent  discoveries  of 
Eoux  and  Yersin,  Klebs,  Loffler,  and  Klein,  by  whom  it  has  been  determined 
that  there  is  an  intimate  relationship  between  human  diphtheria  and  a  some- 
what similar  disease  affecting  certain  of  the  lower  animals,  particularly  cats. 

The  possibility  of  such  a  mode  of  infection  may  perhaps  account  for  the 
fact  that  it  has  often  appeared  impossible  to  trace  any  cause  to  which  an  out- 
break could  be  attributed.  Dr.  Airy,  who  in  1880  undertook  an  inquiry  for 
the  Local  Government  Board,  was  particularly  struck  with  this  point,  and 
he,  in  this  connection,  recalls  the  opinion  of  Prof.  Burdon  Sanderson,  who 
in  1859  reported  that  *  the  circumstances  were  permanently  such  as  to  shut 
out  even  the  possibility  of  personal  communication.'  Dr.  Airy  further  re- 
ported that  the  disease  was  more  prevalent  on  clayey  than  on  sandy  soils, 
that  its  incidence  was  greatest  on  persons  liable  to  throat  affections,  and 
further  that  the  only  view  which  appeared  consonant  with  all  the  facts 
which  he  had  gathered  together,  was  that  which  attributed  the  affection  to 
VOL.  I.  z 


338  HYGIENE 

a  living  organism  capable  of  infecting  milk  and  air  and  of  being  transmitted 
by  wind  currents. 

This  view  of  the  carriage  of  diphtheria  infection  by  milk  has  received 
support  from  several  investigations  on  the  subject,  notably  in  one  conducted 
by  Mr.  Power  during  an  epidemic  of  diphtheria  in  North  London  in  1878, 
in  which  it  appeared  probable  that  the  cow  herself  might  have  been  con- 
cerned in  the  infection  of  the  milk.  A  like  difficulty  in  referring  the  outbreak 
to  a  human  source  is  seen  in  a  report  by  the  same  gentleman  concerning 
an  outbreak  about  ten  years  later  at  York  Town  and  Camberley,  although 
its  relation  to  disease  of  the  cows  belonging  to  the  dairy  farm  from  which  the 
milk  was  obtained  seemed  almost  as  indefinite.  A  similar  possible  source 
of  infection  is  suggested  in  reference  to  an  outbreak  investigated  by  Mr. 
Power  at  Hendon  in  1883,  Dr.  Buchanan  saying  in  his  report  for  that  year 
that  '  at  Hendon  it  was  difficult  to  refuse  this  explanation  of  the  facts, 
since  the  milk  at  the  very  time  it  was  operative  for  harm  .  .  .  exhibited  a 
peculiar  ropiness  and  unpleasant  taste  which  caused  some  of  its  habitual 
consumers  to  return  it  to  the  dairy  ;  and  for  these  phenomena,  no  condition 
about  the  dairy  or  its  utensils  could  be  regarded  as  responsible.' 

Prior  to  this,  however,  Dr.  Thursfield,  in  a  series  of  papers  contributed  to 
the  Lancet  in  1878,  had  expressed  his  opinion  that  diphtheria,  essentially  a 
disease  of  rural  districts,  otherwise  the  most  healthy  as  indicated  by  the 
fever  death-rate,  was  intimately  connected  as  regards  local  conditions  with 
structural  dampness  of  habitation.  This  statement,  at  the  time,  being  con- 
trary to  accepted  ideas,  was  severely  challenged  by  those  who  maintained  that 
typhoid  fever  and  diphtheria  alike  were  the  result  of  exposure  to  filth 
accumulation,  and  that  the  explanation  of  the  special  incidence  of  diphtheria 
upon  rural  districts,  which  was  at  that  time  apparent,  was  due  to  the  fact  that 
the  towns  had  relatively  made  more  sanitary  progress  than  the  country  dis- 
tricts. Dr.  Simpson,  in  reporting  on  an  epidemic  at  Shaftesbury  in  1885, 
refers  especially  to  an  outbreak  in  three  successive  Novembers  in  an  old 
dilapidated  house  standing  on  a  water-logged  soil,  where  the  walls  of  the 
ground  and  upper  floors  were  found  to  be  wet  and  covered  with  moulds,  and 
the  woodwork  rotten. 

That  structural  dampness  of  dwellings  is  a  most  important  factor  in  the 
development  of  diphtheria  is  now  generally  admitted,  such  a  condition  being 
most  favourable  for  the  incidence  and  severity  of  the  affection  and  the  per- 
sistent vitality  of  the  germ  of  the  disease.  As  Dr.  Thursfield  has  pointed  out, 
this  dampness  of  houses  may  depend  on  the  subsoil  water  being  so  close  to  the 
surface  that  the  cellar  always  contains  more  or  less  water,  or  upon  the  house 
being  built  upon  a  retentive  clay  without  the  precaution  having  been  taken  of 
providing  a  damp-proof  substratum,  but  even  more  frequently,  upon  the  house 
being  deeply  embedded  at  the  back  or  slightly  all  around.  The  material  of 
which  a  house  is  built  may  also  be  conducive  to  a  similar  result,  a  porous 
absorbent  stone  retentive  of  moisture  being  very  favourable  to  the  incidence 
of  the  disease.  Trees  surrounding  and  shutting  in  the  house  will  naturally 
Aggravate  the  liability  to  the  deposition  and  retention  of  moisture,  provided 
that  the  materials  of  which  it  is  built  are  of  a  nature  favourable  to  such 
conditions. 

Although  dampness  of  site  is  undoubtedly  a  factor  in  the  production  of 
outbreaks  of  diphtheria,  particularly  if  such  dampness  be  due  to  persistent 
leakage  from  imperfect  sewers  or  cesspools,  it  does  not  appear  that  there  is 
any  direct  relation  between  the  occurrence  of  an  epidemic  and  a  rise  or  fall 
of  subsoil  water,  provided  that  the  structure  and  atmosphere  of  the  houses 
are  not  affected.     Many  districts,  which  although  usually  dry  are  liable  to 


THE  INFLUENCE   OF  SOIL   ON  IlEALTU  339 

•occasional  floods,  are  remarkably  free  from  the  disease,  so  that  it  appears  that 
a  persistent  impregnation  of  the  soil  witli  moisture  is  of  more  importance 
than  fluctuations  in  the  height  of  the  grou.nd  water,  particularly  if  these  have 
any  considerable  range. 

It  should  be  stated  that  Bruhl  and  Johr  claim  to  have  proved  that  an 
increase  of  mortality  from  this  disease  is  closely  connected  with  prevalent 
atmospheric  conditions,  the  maximum  mortality  being  in  those  places  where 
there  is  throughout  the  year  less  equability  of  temperature  and  humidity  of 
'the  air.  Where  these  conditions  are  more  equable,  or  where  the  air  is  warm 
and  dry,  the  mortality  is  lowest.  These  statements  are  perhaps  not  so  much 
,at  variance  with  the  view  already  advocated  as  might  appear  at  first  sight,  since 
the  less  or  greater  humidity  of  the  lower  strata  of  the  atmosphere  depends  in 
great  measure  on  the  dryness  or  the  reverse  of  the  upper  layers  of  the  soil. 

That  the  specific  poison  of  diphtheria  consists  of  a  living  organism  is  now 
pretty  generally  recognised,  although  there  is  some  doubt  as  to  its  identity. 
Klebs  first  pointed  out  that  there  is  uniformly  present  in  diphtheritic  mem- 
branes a  bacillus  possessing  definite  morphological  characters  which  he  be- 
lieved to  be  peculiar  to  this  disease.  In  addition,  there  are  always  present  a 
great  variety  of  micro-organisms,  chiefly  micrococci,  which  have  no  particular 
significance.  Loffler  confirmed  the  frequent  presence  in  diphtheria  of  this 
bacillus,  and  succeeded  in  isolating  and  growing  it  in  suitable  media,  parti- 
cularly on  serum  or  in  agar  beef  broth.  He  stated,  however,  that  it  was  not 
possible  to  find  it  in  a  number  of  cases  that  he  examined,  but  Klein  has  uni- 
formly found  it  in  all  recent  cases  examined  by  him  ;  moreover,  Klein  has 
isolated  the  bacillus  in  cultures  and  produced  therewith  diphtheritic  disease 
in  lower  animals. 

Eoux  and  Yersin,  recently  working  at  the  Pasteur  Institute,  adopt  the 
Klebs-Loftier  bacillus  as  the  essential  cause  of  diphtheria,  stating  not  only 
that  they  have  been  able  to  transmit  the  disease  to  pigeons  and  rabbits  by 
inoculations  of  this  baciUus,  but  that  the  nutrient  fluid  in  which  it  had  been 
grown,  after  being  passed  through  a  filter  of  unglazed  porcelain,  when  injected 
into  the  subcutaneous  tissues  of  various  animals  (the  required  quantity  de- 
pending on  the  age  of  the  culture),  produced  either  a  rapidly  fatal  result  or 
a  less  acute  illness  with  subsequent  paralytic  symptoms.  These  investigators 
found,  moreover,  that  a  growth  of  the  baciUus  may,  if  protected  from  air  and 
light,  be  kept  for  an  almost  indefinite  time  and  still  produce  characteristic 
symptoms  in  animals  inoculated  with  it,  but  that,  exposed  to  air  and  light, 
it  speedily  loses  its  virulence.  These  facts  would  appear  to  warrant  the  sup- 
position that  the  bacilli  may  exist,  for  an  indefinite  period,  dormant  in  soil, 
particularly  that  beneath  dwelling-houses,  where,  protected  from  light  and 
excess  of  oxygen,  and  supplied  with  a  necessary  amount  of  heat,  they  would 
regain  their  full  energy  as  soon  as  their  environment  became  more  favom'able. 
If  the  pathogenic  nature  of  the  Klebs-Loflier  bacillus  be  admitted,  it  will  be 
obvious  that  such  a  state  of  affairs  may  have  an  important  bearing  in  connec- 
tion with  outbreaks  of  diphtheria  where  there  has  been  no  evidence  of  im- 
portation of  the  disease  from  without,  but  where  there  is  a  history  of  a  previous 
outbreak  in  the  same  house,  perhaps  after  a  long  interval  of  years. 

Cholera 
The  first  and  most  obvious  characteristic  of  this  disease  is  its  preference 
for  particular  localities  ;  the  conditions  which  determine  its  local  settlement 
being,  as  was  shown  by  Sir  John  Simon  in  his  Fifth  Annual  Report  (1853), 
certain  demonstrable  physical  peculiarities  which  consist  in  the  conjunction 
of  dampness  with  organic  decomposition. 

z2 


340 


HYGIENE 


Thus  cholera  is  known  to  attack  with  the  greatest  virulence  places  of  low 
elevation,  especially  those  which  are  thickly  populated,  and  which  have  to 
contend  not  only  with  their  local  impurity,  but  also  "with  impurities  carried 
into  them  by  the  drainage  of  ground  water  from  places  situated  at  a  higher 
level.  A  low  level  in  itself,  however,  is  not  sufficient,  unless  it  be  combined 
with  a  certain  density  of  population,  and  it  would  appear  that  a  comparatively 
high  temperature,  both  of  air  and  soil,  is  a  necessary  factor  for  the  epidemic 
extension  of  the  disease.  Dr.  Macnamara  states  that  cholera  is  more  rife  in 
low'  alluvial  soils,  and  that  it  advances  from  east  to  west,  or  exactly  in  the 
direction  fi'om  the  least  to  the  greater  recorded  falls  of  rain,  and,  as  a  conse- 
quence, just  in  time-relation  wath  the  lowness  of  the  ground  water,  which 
will  be  first  loAvest  in  eastern  districts  and  last  lowest  in  western  districts. 

Cholera,  which  has  been  kno"s^ai  to  be  endemic  in  certain  parts  of  India 
since  1817,  first  appeared  in  England  in  1831-32.  A  second  great  visitation 
occurred  in  1848-49,  when  the  number  of  fatal  attacks  amounted  to  53,293,  in 
addition  to  a  great  increase  in  the  death-rate  from  diarrhoea.  Even  at  this 
time  the  fact  became  fully  recognised  that  the  spread  of  the  epidemic  was  largely 
influenced  by  filth-conditions  afl'ecting  air,  soil,  and  water.  In  1853  and 
1854  the  disease  again  appeared  in  London,  the  greatest  number  of  deaths  m 
both  years  being  recorded  in  the  summer  and  autumn  months.  In  these 
epidemics  the  water-supply  appeared  to  be  the  main  factor  in  the  propagation 
of  the  disease,  a  point  which  will  be  found  fully  treated  of  in  another  section  ; 
but,  as  Dr.  Greenhow  pointed  out  in  reporting  to  the  General  Board  of 
Health,  polluted  water  was  by  no  means  the  only  cause  of  cholera  spread, 
the  mortality  having  also  '  generally  borne  a  direct  ratio  to  the  amount  of 
atmospheric  contamination  ;  '  soil  conditions  also  playing  an  important  part. 

In  1865,  an  outbreak  involving  some  sixty  persons  occurred  in  Southamp- 
ton, whither  the  disease  appeared  to  have  been  brought  by  steam  vessels 
from  the  East,  where  the  Mecca  pilgrims  had  been  decimated  by  the  disease 
in  the  previous  year.  Again  the  epidemic  first  definitely  appeared  here  in  the 
months  of  September  and  November,  although  isolated  cases  had  been  re- 
corded as  early  as  the  middle  of  July.  Other  seaports  w^ere  aflected  almost 
simultaneously,  and  the  disease  gradually  spread,  causing  eventually  the 
death  of  14,378  individuals  in  England  as  a  whole,  of  which  London 
accounted  for  nearly  one-third. 

In  each  of  these  epidemics  the  number  of  deaths  had  gradually  decreased,, 
although  the  total  population  had  largely  increased,  and  since  1866  cholera 
has  never  succeeded  in  obtaining  a  firm  footing  in  this  country  ;  '  a  result 
which  is  no  doubt  due  to  the  steady  removal  from  amongst  the  people  of 
those  insanitary  conditions  which  are  essential  to  its  epidemic  spread,  and 
to  the  increasing  security  afibrded  by  those  measures  of  imperial  and  local 
sanitary  administration,  by  which  it  is  sought  to  diminish  sickness  and 
mortality  from  all  preventable  diseases  '  (Thorne  Thorne). 

The  incidence  of  cholera  mortality  in  England  during  the  epidemics  of 
1849,  1854,  and  1866  is  shown  in  the  following  table  : — 

Clwlera  Mortality 


Date 

i 

England  and  Wales 

Louduu 

Total  deaths 

Deaths  per  10,000 
living 

Total  deaths 

Deaths  per  10,000 
living 

1849 
1854 
1866 

53,293 
20,097 
14,378 

30 
11 

7 

13,565 

10,684 

5,548 

51 
43 

18 

THE  INFLUENCE   OF  SOIL   ON  HEALTH  341 

In  this  country  the  theory  that  cholera  is  mainly  spread  by  means  of  the 
'drinking-water  has  received  much  support,  many  instances  in  which  this 
had  undoubtedly  taken  place  having  been  recorded  by  Dr.  Snow  and  other 
observers  ;  but  it  must  be  remembered  that  dissemination  may  come  about 
in  other  ways  :  '  excrement-sodden  earth,  excrement-reeking  air,  excrement- 
'tainted  water ;  these  are  for  us  the  causes  of  cholera.' 

In  Germany,  however,  Pettenkofer  and  other  observers  have  maintained 
that  the  diffusion  of  cholera  is  mainly  due  to  movements  of  the  soil  water, 
the  fundamental  proposition  being  that  cholera  never  prevails  epidemically 
where  the  soil  is  impermeable  to  water,  or  where  the  level  of  the  ground 
water  is  not  liable  to  fluctuations.  According  to  Pettenkofer  the  condition 
of  soil  with  which  cholera  is  most  apt  to  prevail  is  that  which  occurs  when 
the  ground  water,  after  having  attained  a  higher  level  than  usual,  com- 
mences again  to  fall.  It  is  conceivable  that  an  outbreak  might  be  caused  in 
this  way  by  noxious  organic  material  being  washed  into  wells  to  which  it 
•could  not  ordinarily  gain  access ;  or  again,  it  might  be  due  to  micro- 
organisms present  in  the  upper  layers  of  the  soil,  which  had  been  awakened 
into  activity  by  the  combined  influence  of  heat  and  moisture,  becoming 
diffused  into  the  atmosphere  when  the  superficial  stratum  of  the  earth  again 
became  comparatively  dry. 

As  these  views  have  apparently  met  with  but  little  acceptance  in  Eng- 
land, it  may  be  worth  while  to  mention  a  curious  fact  quoted  by  Fagge  in 
connection  with  the  East  London  epidemic  of  1866,  which  appears  to  be 
■strongly  in  favour  of  Pettenkofer 's  theory.  In  a  school  at  Limehouse  were 
four  hundred  pauper  children,  not  one  of  whom  was  attacked  with  cholera 
•or  with  diarrhoea.  Now,  the  house  had  its  sole  water-supply  from  the  Old 
Ford  reservoirs,  by  which  it  had  been  thought  the  disease  was  spread,  and 
the  children  at  all  times  made  free  use  of  the  water.  A  special  investigation 
of  the  soil  beneath  this  school  brought  to  light  the  fact  that  it  stood  upon  a 
thick  layer  of  fine  brick-earth,  and  not  of  gravel,  as  appeared  to  be  the  case 
with  the  streets  immediately  adjacent. 

It  should,  of  course,  be  remembered  that  Pettenkofer  admits  the  neces- 
sity for  the  presence  of  a  specific  germ,  which,  however,  is  only  able  to 
assert  itself  in  a  virulent  manner  when  its  environment  is  suitable,  so  that 
the  state  of  the  soil  is  really  a  predisposing  cause.  Nageli,  a  supporter  of 
Pettenkofer,  further  suggests  that  the  soil  gives  off  certain  microzymes 
which  must  be  present  in  the  body  of  everyone  who  is  to  afford  favourable 
conditions  for  the  development  of  another  set  of  microzymes  derived  from  a 
pre-existing  case  of  cholera,  which  would,  however,  probably  be  too  few  to  be 
able  to  overcome  the  resistance  of  the  living  tissues,  unless  these  latter  had 
£rst  been  weakened  by  the  previous  invasion  of  organisms  peculiar  to  the  soil. 

The  researches  of  Lewis  and  Cunningham  at  Calcutta  seem  to  prove  that 
in  that  place  the  ground-water  level,  and,  in  a  less  marked  degree,  the  rain- 
fall, bear  an  inverse  relation  to  the  prevalence  of  the  disease.  When  the 
latter  is  at  a  maximum  the  water  level  is  at  a  minimum,  and  when  the 
water  level  is  at  a  maximum  the  prevalence  of  cholera  is  at  a  minimum. 
There  is,  however,  no  correspondence  as  between  one  year  and  another  or 
•one  month  and  another  ;  or,  in  other  words,  the  absolute  height  of  the  sub- 
soil water  is  hy  itself  of  no  significance  for  the  amount  of  sickness.  Still, 
they  call  attention  to  the  fact  that  the  two  years— 1871  and  1872— in  their 
eight  years'  period,  which  had  the  minimum  number  of  cholera  cases,  were 
•distinguished  by  the  remarkably  high  level  of  the  subsoil  water. 

Hirsch  makes  a  great  point  of  the  statement  that  it  is  always  an  essential 
circumstance  that  the  soil  be  saturated  with  moisture,  but  only  to  that  degree 


342  HYGIENE 

at  which  it  is  still  pervious  to  air,  and  that  the  organic  matters  accumulateJ 
in  it  should  undergo  decomposition;  under  the  influence  of  somewhat  high 
temperatures.  Consequently  the  question  is  not  as  to  the  extent  of  the  stra- 
tum of  soil  saturated  with  moisture  and  permeable  to  air,  or,  in  other  words, 
a  question  of  the  higher  or  lower  level  of  the  subsoil  water,  but  it  is  a  ques- 
tion whether  such  a  stratum  exists  at  all,  and  that  is,  in  his  opinion,  the  gist 
of  the  much  quoted  and  much  misunderstood  doctrine  of  Pettenkofer  as 
to  the  significance  of  the  height  and  fluctuations  of  the  subsoil  water  in  the 
production  and  diffusion  of  cholera. 

This  conception  of  the  part  played  by  variations  in  the  amount  of  water 
m  the  soil  is  indeed  upheld  by  Pettenkofer  himself,  who,  writing  in  1B70, 
says  :  '  In  my  view,  the  level  of  the  subsoil  water  reveals  nothing  more  than 
this,  viz.,  the  limits  of  a  certain  degree  of  humidity  in  a  porous  stratum  of 
soil,  or  the  limits  within  which  the  pores  are  kept  constantly  full  of  water 
and  all  the  air  driven  out  of  them.  Between  that  degree  of  humidity  and 
absolute  dryness  of  the  porous  stratum,  there  are  all  those  gradations  when 
the  pores  are  filled  in  part  with  air  and  in  part  with  water  in  varying  propor- 
tions, which  we  include  altogether  under  the  terms  "  moist  "  or  "  wet."  The 
point  at  which  the  pores  are  completely  closed  by  water,  is  one  that  may  be 
observed  with  ease  and  certainty,  and  I  have  therefore  chosen  the  level  of 
the  subsoil  water  merely  as  an  easily  seen  gauge  and  index  of  certain  states^ 
of  humidity  in  the  stratum  of  porous  and  permeable  soil  which  overlies  the 
subsoil  water,  an  index,  viz.,  of  the  fluctuations  in  the  state  of  humidity 
^^ithin  a  given  period,  and  of  the  time  that  any  one  degree  has  lasted. 
Whether  that  index  is  a  few  feet  nearer  to  or  farther  from  the  surface  does 
not  affect  the  value  of  its  revelations.  For  the  importance  of  the  index  lies 
in  this  :  that  it  declares  the  changes  in  the  humidity  of  the  overlying  strata, 
by  means  of  the  natural  effects  of  those  changes.  The  fluctuations  in  the 
level  of  the  subsoil  water  have  a  meaning  for  aetiology  only  because  they 
are  traced  back  to  those  primary  influences  by  which  air  and  water  are  made 
to  share  in  varying  proportion  the  possession  of  the  pores  of  an  impregnated 
soil.  Beyond  that,  they  have  no  significance  ;  .  .  .  looked  at  by  itself  and 
for  its  own  sake,  the  condition  of  the  subsoil  water  has  as  little  significance 
as  the  hands  and  dial  of  a  watch  dissociated  in  thought  from  the  works  to 
which  they  belong.' 

Lewis  and  Cmmingham  found  no  such  close  relation  as  that  between 
the  cholera-curve  and  the  curve  of  the  subsoil  water  level,  in  connec- 
tion with  either  conditions  of  soil  temperature  or  amomit  of  carbonic  acid, 
although,  in  so  far  as  soil  moisture  appears  to  determine  the  amount  of  car- 
bonic acid  in  the  soil,  there  was  a  general  coincidence  in  regard  to  the  latter 
also.  The  relations  between  rainfall  and  prevalence  of  cholera,  were  not  so 
strongly  marked  as  those  between  the  latter  and  the  water  level ;  and  it  even 
appeared  as  though  the  inverse  relation  between  conditions  of  water  level 
and  prevalence  of  cholera  were  in  some  degree  more  distinct  than  the  direct 
one  between  the  water  level  and  the  rainfall. 

In  another  place  Dr.  Cunningham  further  says :  '  One  point  seems 
worthy  of  remark,  and  that  is,  that  there  is  no  evidence  of  the  existence  of 
any  common  condition  affecting  local  sources  of  water  supply,  and  simul- 
taneously affecting  the  prevalence  of  cholera  and  bowel  complaints.'  And 
again  :  '  If  the  concurrence  of  a  low  water  level  and  high  prevalence  of  cholera 
in  Calcutta  be  more  than  a  mere  coincidence — if  any  causal  relation  exist 
between  the  two  phenomena — it  cannot  be  a  direct  simple  one  depending  on 
the  mere  mass  of  water  in  the  soil,'  which,  however,  bears  out  Pettenkofer's. 
contention. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH 


343 


Dr.  Macnamara  and  others  have  asserted  that  not  only  is  rain  connected 
with  the  development  and  dissemination  of  cholera  poison,  but  that  in  India 
no  widespread  epidemic  can  occur  unless  during  or  after  rain.  On  the 
other  hand,  there  can  be  no  doubt  that  the  opposite  effect  is  not  infrequent, 
particularly  if  the  rainfall  be  excessive,  prevalence  of  the  disease  being  pre- 
vented by  destruction  of  the  micro-organisms,  partly  as  the  direct  result  of 
the  amount  of  water  in  the  soil,  and  partly  from  their  being  carried  further 
from  the  surface  where  they  are  no  longer  among  surroundings  favourable 
to  their  continued  existence.  This  fact  is  well  shown  in  the  following  table 
compiled  by  Dr.  Macpherson : — 

Table  showing  Deaths  from  Cliolera  in  Calcutta  for  Twenty -six  Years 


Month 

Cholera.    Total 

Eainfall 

Average 

Range  of 

number  of  deaths 

temperature 

temperature 

Inches 

Fahr. 

Fahr. 

January   . 

7,150 

0-21 

63-4° 

17-9° 

February  . 

9,346 

0-42 

74-2 

17-3 

March 

14,710 

1-13 

82-9 

16-3 

April 

19,382 

2-40 

86-6 

14-7 

May 

13,335 

4-29 

89-0 

13-3 

June 

6,325 

10-10 

86-2 

9-0 

July 

3,979 

13-90 

84-0 

6-4 

August     , 

3,440 

14-40 

82-6 

5-2 

September 

3,985 

10-40 

83-8 

6-6 

October    . 

6,211 

4-72 

81-1 

8-8 

November 

8,323 

0-90 

75-4 

14-2 

December 

8,159 

0-13 

66-9 

16-4 

Similarly  Fodor  has  shown  at  Buda-Pesth  that,  although  a  certain  amount 
of  moisture  of  the  soil  is  necessary  for  the  appearance  of  an  epidemic  of  cholera, 
yet  its  spread  is  immediately  checked  if  there  be  a  considerable  fall  of  rain. 
Thus,  in  1866,  not  only  was  the  rainfall  above  the  average,  but  the  level  of 
the  Danube  rose  unusually  high,  and,  as  a  consequence,  cholera,  which  had 
been  prevalent,  fell  off,  notwithstanding  that  the  atmospheric  temperature 
was  high.  Later  on  the  rainfall  diminished,  the  Danube  fell  rapidly,  and 
cholera  once  more  asserted  itself.  In  1878  also,  the  disease  increased  in 
July  coincidently  with  a  slight  rainfall,  reaching  its  highest  point  for  the 
year  in  the  following  month.  In  the  previous  year  cholera  had  not  been 
present,  due  apparently  to  the  fact  that  there  had  been  an  exceptionally 
heavy  rainfall  during  the  summer  and  autumn. 

At  Buda-Pesth  the  epidemic  zone,  as  it  is  termed  by  Fodor,  coincides  with 
those  parts  of  the  town  which  lie  lowest,  there  being,  according  to  this  ob- 
server, an  unmistakable  connection  between  the  height  of  the  ground  level 
and  cholera  prevalence.  He  shows,  however,  that  there  are  certain  streets 
which  have  been  severely  visited  at  various  times,  although  situated  in  the 
higher  parts  of  the  town ;  but  the  anomaly  is  apparently  due  to  their  being 
on  the  border  of  high  ground,  below  which  the  surface  sinks  down  suddenly. 
Pettenkofer  observed  the  same  fact  in  the  cholera  epidemic  of  1854  ;  houses 
similarly  situated  suffering  as  severely  as  those  on  a  much  lower  level.  Cordes 
also  states  that  in  each  of  the  eleven  cholera  epidemics  which  occurred  at 
Quebec  between  the  years  1832  and  1866,  the  disease  was  especially  prevalent 
in  the  same  parts  of  the  town,  viz. — four  different  areas  which  were  sunk 
below  the  general  level ;  and  also  that  when  the  disease  was  introduced  into 
the  higher  parts  of  the  town  it  did  not  spread. 

A  similar  observation  is  recorded  by  Gilnther  with  regard  to  an  epidemic 
of  cholera  which  occurred  at  Dresden  in  1873,  when  a  single  street  was 


344  HYGIENE 

particularly  affected,  more  tlian  half  of  the  inhabitants  of  twenty-two  houses 
invaded  within  a  short  time  of  one  another  having  died.  In  this  instance 
the  soil  was  found  to  be  very  polluted  at  the  time  of  the  epidemic,  and  the 
drain  connected  with  these  houses  had  apparently  been  blocked  for  a  con- 
siderable time. 

With  regard  further  to  the  vexed  question  as  to  whether  cholera  is  most 
predisposed  to  by  certain  conditions  of  water  or  soil,  although  it  can  be 
readily  vmderstcol  that  the  disease  may  result  from  the  ingestion  of  water 
containing  the  evacuations  of  cholera  patients,  it  may  also  be  supposed  that 
the  use  of  impure  water  of  any  kind  may  aid  the  production  of  the  disease, 
although  it  cannot  absolutely  produce  it.  In  this  way  we  may,  perhaps, 
reconcile  the  conflicting  theories,  since,  as  has  been  showai  previously,  when 
the  ground  water  commences  to  fall  after  an  unusually  high  rise,  it  would 
naturally  be  preceded  by  a  fall  in  the  wells  and  other  sources  of  drinking 
water,  and  thus  the  drainage  of  the  upper  foul  layers  of  the  soil  would  be 
carried  by  the  ebbing  tide  of  ground  water  into  such  outlets  ;  and  so  the 
water  supplied  to  a  neighbouring  population  would  become  dangerously  con- 
taminated, and  the  more  so  the  fouler  the  surface  layers  of  the  soil.  The 
facts  which  will  be  found  quoted  in  another  section  on  the  influence  of  the 
Lambeth  water  during  the  epidemic  of  1854  seem  to  support  this  view,  and 
we  have  further  evidence  in  favour  of  it  derived  from  the  investigation  of 
later  outbreaks  in  Germany.  The  water  may  act  in  this  way  :  either  by  caus- 
ing a  constant  tendency  to  diarrhoea,  a  disease  wiiich  is  for  the  most  part 
exceedingly  prevalent,  both  antecedent  to,  and  concomitantly  with,  cholera 
epidemics,  or  by  carrying  into  the  alimentary  canal  organic  matter  of  an 
injurious  nature.  This  either  affords  a  fitting  pabulum  for  the  materies  morbi 
of  cholera  when  brought  into  contact  with  it,  or  else  may  undergo  special 
chemical  changes  under  the  influence  of  small  doses  of  the  cholera  microbe 
as  may  convert  it  into  a  still  more  virulent  poison  ;  or,  again,  by  lowering 
the  normal  powers  of  resistance  of  the  body,  may  render  it  an  easier  prey, 
not  only  to  cholera,  but  to  disease  in  many  other  forms  as  well. 

Tlic  '  Comma  '  Bacillus 

The  researches  of  Koch,  when  working  on  the  German  Cholera  Commis- 
sion, have  rendered  it  highly  probable  that  a  particular  micro-organism,  termed 
the  '  comma  bacillus,'  is  always  associated  with  Asiatic  cholera.  He  has 
found  it  not  only  in  the  alvine  discharges  of  patients  sufi'ering  from  the 
disease,  but  also  in  the  soil  and  in  the  water-tanks  of  infected  districts. 
Nearly  fifty  years  previously  Pacini  had  described  '  vibrios '  as  being  present 
in  the  intestinal  discharges  of  cholera  patients,  but  whether  these  bodies  were 
identical  with  Koch's  bacillus  is  uncertain. 

The  specific  micro-organisms  called  '  comma  bacilli,'  on  account  of  their 
shape,  are  to  be  found  during  the  acute  stage  of  cholera  in  the  rice-water 
discharge  from  the  intestines,  and  consist  of  little  curved  rods  of  about  the 
thickness  of  a  tubercle  bacillus,  but  only  half  its  length.  They  are  actively 
motile,  and  multiply  by  fission,  often  producing  during  the  process  S-shaped 
or  spiral  forms  from  the  progeny  of  an  individual  bacillus  remaining  m 
contact  with  one  another. 

As  to  this  bacillus,  Macleod  and  Milles  describe  the  following  charac- 
teristic points :  '  It  grows  in  and  liquefies  slightly  alkaline  gelatine  ;  more 
slowly  in  neutral,  scarcely  at  all  in  slightly,  and  not  at  all  in  markedly  acid 
gelatine.  On  a  gelatine  plate  cultivation  the  individual  colonies  are  round, 
and  lie  in  a  funnel-shaped  cavity ;  when  viewed  with  transmitted  hght  and 
magnified,  they  look  like  ground  glass,  and  the  edge  of  the  colony  is  finely 


THE  INFLUENCE    OF  SOIL    ON  HEALTH  345 

notclied.  In  a  gelatine  tube  a  funnel-shaped  cavity  forms  at  the  top  of  the 
puncture  made  by  the  inoculating  wire,  and  lying  in  this  cavity  there  is  what 
looks  like  an  inverted  air-bubble  with  its  top  on  a  level  with  tlie  surface  of 
the  jelly  and  open  to  the  air ;  along  the  puncture  the  gelatine  lif^uefies,  and 
in  this  may  be  seen  with  the  naked  eye  the  whitish  mass  of  colonies,  par- 
ticularly at  the  lowest  part ;  in  from  three  to  four  weeks  liquefaction  spreads 
to  the  whole  mass,  the  bacilli  falling  to  the  bottom  as  a  greyish-white  sediment, 
having  a  faint  orange  tint  in  certain  lights,  and  if  undisturbed  a  perfectly  trans- 
parent liquid  separates  a  whitish  scum  on  the  top  from  the  sediment  below.' 
Like  most  other  pathogenic  organisms,  it  grows  best  at  about  the  body  tem- 
perature, any  considerable  range  below  or  above  this  inhibiting  the  growth, 
although  the  bacillus  is  not  destroyed  if  the  temperature  be  reduced  to  the 
freezing  point.  It  is  aerobic,  as  if  air  be  excluded  growth  ceases  ;  while  it  is 
killed  altogether  by  drying,  as  apparently  spore  formation  does  not  take  place. 

Klein,  however,  on  repeating  Koch's  experiments,  has  been  unable  to 
confirm  them,  and  consequently  denies  the  pathogenic  importance  of  the 
comma  bacillus.  It  has  been  shown  that  a  similar  organism  is  to  be  found 
under  normal  circumstances  in  the  mouth,  and  Klein  believes  its  presence 
dn  the  intestine  to  be  merely  accidental,  the  large  numbers  which  he  allows 
are  always  to  be  found  in  cholera  dejecta  being  due,  in  his  opinion,  to  the 
state  of  the  alimentary  canal  being  favourable  to  their  multiplication. 

Great  stress  has  also  been  laid  on  the  ease  with  which  the  vitality  of  the 
comma  bacillus  is  destroyed,  as  affording  an  argument  against  the  likelihood 
of  its  being  the  medium  of  infection.  Not  only  are  they  killed  by  drying, 
but  also  by  the  addition  of  small  quantities  of  acid,  so  that  they  may  be  given 
hy  the  mouth  in  the  case  of  the  guinea-pig  without  the  animal  being  affected, 
as  the  acidity  of  its  gastric  juice  is  sufficient  to  destroy  them.  In  order  to 
obviate  such  an  event  when  experimenting  on  the  possibility  of  producing 
the  disease  in  the  guinea-pig,  Koch  injected  soda  solution  into  the  stomach, 
and  thus  in  some  instances  enabled  the  bacilli  to  reach  the  duodenum  unin- 
jured by  the  secretion  of  the  stomach.  Weak  disinfectants  and  the  presence 
of  putrefactive  organisms  are  also  inimical  to  the  comma  bacillus,  Cun- 
ningham having  shown,  for  instance,  that  if  a  portion  of  a  cultivation  of 
commas  was  inoculated  into  water  or  soil,  the  length  of  time  during  which 
they  could  still  be  recognised  in  the  living  state  depended  directly  on  the 
amount  of  pollution  of  the  medium  into  which  they  were  sown.  Thus  in 
one  series  of  experiments,  when  water  polluted  witli  excreta  was  used,  it 
was  found  that  all  the  bacilli  had  disappeared  in  a  period  varying  from  four 
to  nine  days,  while  if  the  water  had  previously  been  sterilised  by  boiling,  they 
were  found  as  late  as  the  twenty-fifth  day.  Kitasato  has  apparently  estab- 
lished the  same  fact  with  regard  to  the  action  on  the  bacilli  of  the  micro- 
organisms present  in  f^ces. 

From  these  experiments  it  would  appear  that  cholera  dejecta,  when  buried 
in  the  soil  or  thrown  into  water,  would  be  Hkely  to  be  rendered  innocuous 
"within  a  comparatively  short  time,  but  in  this  connection  an  instance  of  in- 
fection by  water  described  by  Macnamara  is  worthy  of  attention.  He  states 
that  '  a  small  quantity  of  the  dejecta  of  a  cholera  patient  was  known  to  have 
been  washed  into  a  vessel  containing  water ;  the  mixture,  after  being  exposed 
to  the  heat  of  the  sun  for  one  day,  was  swallowed  by  nineteen  men  on  the 
following  morning  ;  within  three  days  five  of  these  were  affected  with  cholera.' 

Nicati  and  Eietsch  have  also  shown  that  cholera  bacilli  are  capable  of 
existing  for  as  long  as  eighty-one  days  in  the  water  at  the  port  of  Marseilles, 
so  that  it  is  possible  there  may  have  been  some  source  of  fallacy  in  Cunning- 
ham's experiments. 


346  HYGIENE 

Moreover,  tlicse  observers  found  that  a  disease  very  similar  to,  if  not 
identical  with  cholera,  could  be  induced  in  guinea-pigs  by  the  injection  of 
comma  bacilli  into  the  small  intestine.  Koch,  as  has  been  said,  improved  on 
these  experiments  by  giving  the  culture  by  the  mouth,  mixed  in  sufficient  of 
an  alkaline  solution  to  prevent  the  destructive  action  of  the  gastric  juice,  and 
at  the  same  time  inhibiting  peristalsis  by  the  use  of  tincture  of  opium.  *  Ex- 
periments were  made  on  thirty-five  guinea-pigs  ;  of  these,  thirty  died  of  cholera. 
The  symptoms  during  life  and  the  appearances  after  death  were  identical 
■with  those  found  in  guinea-pigs  which  had  received  duodenal  injections.' 

The  results  thus  obtained  by  Koch  have  been  fully  confirmed  by  MacleocE 
and  Milles,  who  come  to  the  conclusions  that  the  comma  bacillus  is  invariably 
present  in  cases  of  Asiatic  cholera,  although  there  is  no  evidence  to  show 
that  it  is  a  normal  inhabitant  of  the  human  alimentary  canal ;  that  when 
introduced  into  the  small  intestine  of  the  guinea-pig  in  the  manner  and  with 
the  precautions  already  mentioned,  the  organism  multiplies  in  the  alimentary 
canal,  and  that  associated  with  such  growth  changes  are  found  similar 
to  those  which  are  known  to  occur  in  Asiatic  cholera  when  the  human  being 
is  attacked. 

From  a  review  of  all  the  evidence  brought  forward  by  the  supporters  and 
antagonists  of  Koch's  views  respectively,  it  may  fairly  be  stated  that  the- 
balance  of  scientific  opinion  is  distinctly  in  favour  of  the  pathogenic  nature 
of  the  comma  bacillus.  Finkler  and  Prior,  indeed,  have  described  another 
bacillus  found  by  them  in  cases  of  cholera  nostras,  which,  however,  is  not 
only  readily  distinguished  from  Koch's  bacillus  by  the  manner  of  its  growth 
in  various  nutrient  media,  but  which  is  probably  never  present  in  cases  of 
true  cholera. 

In  the  light  of  what  has  been  stated  with  regard  to  the  aetiology  of  the 
disease,  the  prophylactic  measures  to  be  taken  against  the  invasion  of  cholera 
obviously  comprise  such  as  will  prevent  its  admission  into  a  community,  or 
hinder  its  spread  if  it  be  introduced  from  without ;  it  being  also  of  great 
importance  to  reduce  if  possible  the  individual  susceptibility  to  attack. 

In  this  country  confidence  is  no  longer  placed  in  a  system  of  quaran- 
tine for  the  prevention  of  cholera,  scientists  being  now  for  the  most  part  of 
opinion  that  it  is  not  only  easier,  but  far  more  effective,  to  provide  against  the 
development  of  cholera  by  such  improvements  in  general  sanitation  as  will 
render  it  difficult  for  the  disease  to  obtain  a  footing.  Pettenkofer  has  well 
expressed  the  contrast  between  the  efficiency  of  quarantine  and  local  sanita- 
tion as  safeguards  against  cholera  in  comparing  an  epidemic  to  the  explosion 
of  a  powder  magazine.  The  powder  represents  the  local  conditions  pre- 
disposing to  an  outbreak,  while  the  virus  of  cholera  is  the  spark  which  can 
evade  the  strictest  quarantine.  *  It  is  vdser,  therefore,  to  seek  out  and 
remove  the  powder  than  to  run  after  and  try  to  extinguish  each  individual 
spark  before  it  drops  upon  a  mass  of  powder,  and,  igniting  it,  causes  an 
explosion  which  blows  us  into  the  air  with  our  extinguishers  in  our  hands,' 

It  is  specially  necessary  to  guard  against  pollution  of  the  soil,  since  such 
a  state  of  things  means  in  all  probability  contamination  also  of  water  and  of 
air,  all  of  which  conditions  will  certainly  encourage  the  incursions  of  the  dis- 
ease. Moreover,  since  it  has  been  definitely  proved  that  the  discharges  from 
the  stomach  and  intestines  contain  the  active  agents  for  propagation  of  the 
disease,  and  that  at  the  same  time  the  bacilli  are  more  easily  destroyed  when 
first  carried  out  of  the  body,  the  immediate  disinfection  of  all  such  discharges 
must  be  carried  out  by  some  efficient  substance,  such  as  corrosive  sublimate 
or  carbolic  acid,  which  Koch  has  shown  is  capable  of  killing  the  comma 
bacilli  when  diluted  to  the  extent  of  one  part  in  fifty  with  water. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  847 


MALAIilA 

In  spite  of  the  wide  distribution  of  malarial  fevers,  of  their  disastj'ous 
effects  upon  the  population  of  countries  in  which  they  prevail,  and  of  the 
vast  extent  of  the  literature  of  the  subject,  we  are  unfortunately  almost  as  far 
as  ever  from  an  exact  understanding  of  the  precise  conditions  necessary  for 
their  existence  or  production.  There  is,  however,  a  general  consensus  of 
opinion  that  malaria  most  abounds  in  jungle,  swamps,  and  virgin  forests, 
the  disease  showing  an  evident  relation  to  low  land,  abundant  water,  and 
hot  moist  climates,  and  North  has  called  attention  to  the  fact  that  if  a 
physical  map  of  Italy  be  compared  with  the  map  of  Signor  Torelli  showing 
the  local  distribution  of  malaria,  such  relation  of  the  disease  to  water 
temperature  and  altitude  of  the  land  becomes  well-nigh  a  certainty.  In 
the  province  of  Eome  the  disease  is  found  to  be  generally  most  severe  on 
low-lying  ground  in  valleys  and  in  marshy  districts ;  there,  curiously  enougli, 
the  distribution  of  the  population  is  the  reverse  of  that  which  usually  obtains, 
for  whereas  in  most  civilised  countries  the  population  is  densest  m  the  plains 
and  much  more  sparse  on  the  mountains,  in  the  province  of  Eome  exactly 
the  opposite  state  of  things  holds  good,  the  mountain  population  being  nearly 
2|  times  as  numerous  per  square  kilometre  as  the  dwellers  in  the  plains. 
It  was  this  curious  reversal  of  the  general  rule  that  caused  North  to  carefully 
investigate  the  matter  with  the  object  of  determining,  if  possible,  whether 
it  was  malaria  which  in  the  first  instance  compelled  the  inhabitants  of 
the  plains  to  take  refuge  on  the  hills,  or,  on  the  other  hand,  whether  having 
been  driven  thither  from  political  causes,  malaria  had  stepped  in  subsequent 
to  the  abandonment  of  the  plains,  and  in  either  case  where  and  when  such 
causes  first  came  into  operation.  He  comes  to  the  conclusion  that  the 
Campagna  was  abandoned  from  causes  purely  political,  Nature  being  then 
allowed  her  own  way  in  a  country  where  the  unceasing  toil  of  man  is  required 
to  keep  her  under  control.  In  even  the  later  days  of  the  Roman  Empire, 
places  now  absolutely  uninhabitable  were  not  only  inhabited,  but  held  in 
high  esteem  by  the  Romans  as  health  resorts,  so  much  so  that  the  whole 
coast-line  of  the  province  was  covered  with  their  villas  and  country  houses, 
of  which  the  ruins  still  exist,  and  which  Pliny  states  to  have  been  maintained 
in  a  state  of  magnificence  incompatible  with  the  presence  of  such  an  enemy 
to  health  as  malaria.  There  is  some  evidence,  however,  that  the  Pontine 
district  was  not  all  that  could  be  desired  even  in  those  times,  Seneca  advising 
a  friend  to  avoid  the  neighbourhood  of  Ardea  as  not  being  very  healthy. 
The  invasions  of  the  Goths  swept  away  these  villas,  with  the  gardens,  the 
sacred  groves,  and  the  high  cultivation  that  surrounded  them,  the  population 
being  driven  to  secure  places  in  the  hills.  In  the  seventh  and  eighth  centuries 
widespread  outbreaks  of  fever  occurred,  and  serious  attempts  were  made  by 
various  Popes,  with,  however,  but  slight  success,  to  recolonise  and  cultivate 
the  desolate  country.  There  can  be  no  doubt  but  that  the  reckless  destruction 
of  trees,  which  has  gone  on  steadily  ever  since  it  was  begun  by  the  Goths,  has 
played  a  most  important  part  in  altering  the  local  conditions  and  local  climate 
of  the  country  ;  and  in  comparatively  recent  times  the  destruction  of  timber 
in  the  mountains  has  caused  the  streams  which  rise  in  them  to  become 
uncontrollable  and  destructive,  converting  large  areas  of  low  land  into  bog 
and  swamp,  and  rendering  cultivation  difficult  and  unprofitable. 

A  moist  soil,  particularly  if  uncultivated,  is  then  an  important  factor  in 
the  causation  of  malaria,  particularly  when  associated  with  it  there  is  a  high 
soil  temperature  (about  65°  Fahr.)  and  impurity  of  ground  air  and  of  soil,-. 


MS  HYGIENE 

the  latter  being  usually  of  vegetable  origin.  The  rise  or  fall  of  ground  water, 
by  causing  variations  in  the  amoimt  of  moisture  present,  evidently  plays  an 
important  part  in  producing  or  controlling  periodical  outbreaks  of  paroxysmal 
fevers  in  countries  which  are  liable  to  malaria.  The  development  of  malaria 
may  be  coincident  with  either  a  rise  or  a  fall  of  the  subsoil  water,  although 
Fodor  found  that,  with  an  increased  height  of  the  ground  water,  malaria 
died  away,  while  as  the  soil  became  drier  it  again  put  in  an  appearance. 
Thus,  in  1887,  at  Buda-Pesth  the  soil  was  driest  in  the  summer  and 
autumn,  and  it  was  just  at  this  period  of  the  year  that  the  malaria  curve 
rose  highest,  a  great  increase  of  malaria  following  on  the  sinking  of  the 
moisture  curve  relating  to  a  depth  of  one  metre  below  the  surface.  After- 
wards the  amount  of  moisture  increased  till  the  middle  of  September,  and 
malaria  fell  off  from  the  middle  of  September  to  the  middle  of  October, 
Fodor  considering  that  the  difference  in  time  was  accounted  for  by  the 
incubation  period  of  the  disease. 

Rainfall,  on  the  other  hand,  appears  to  bear  a  direct  relationship  to  the 
disease,  the  malaria  curve  generally  falling  during  the  fall  of  rain,  while  during 
dry  weather  the  curve  at  once  commences  to  rise.  If,  however,  the  malaria 
curve  be  compared  with  the  changes  going  on  in  the  deeper  parts  of  the  soil, 
such  as  the  range  of  moisture  or  the  fluctuations  in  the  amount  of  carbon 
dioxide  (and  so  with  fluctuations  in  the  amount  of  putrefaction  going  on  in  the 
soil),  no  such  connection  can  be  traced.  While,  however,  on  the  other  hand, 
there  is  an  evident  relation  between  the  extent  of  malarious  disease  and  the 
amount  of  moisture  in  the  upper  layers  of  the  soil  and  that  of  the  rainfall, 
the  influence  is  drawn  that  the  malarial  miasma  is  produced  in  the  most 
superficial  layers  of  the  earth  and  is  independent  of  decomposition  changes 
in  the  deeper  portions  of  the  soil,  thus  contrasting  markedly  with  certain  other 
diseases. 

The  temperature  of  the  atmosphere  also  exerts  a  considerable  influence 
on  the  prevalence  of  malaria,  which  has  been  carefully  worked  out  by  Fodor, 
who  found  that  a  continuance  of  high  temperature  for  a  few  days,  at  any 
time  of  the  year,  was  regularly  followed  in  about  a  fortnight  or  three  weeks 
by  an  increase  in  the  number  of  cases  of  malaria.  A  low  temperature,  how- 
ever, may  not  always  check  the  spread  of  malaria,  when  other  favouring 
causes  are  present.  The  rise  of  the  malaria  curve  did  not  immediately  follow 
the  rise  of  summer  heat,  a  certain  degree  of  warmth  being  apparently  needed 
for  the  ripening  of  the  germ  ;  but  curiously  enough  Fodor  found  that  in 
spring  a  relatively  small  amount  of  warmth  sufficed  to  bring  about  an  in- 
crease of  malaria,  his  experience  on  this  point  being,  moreover,  supported  by 
other  observers.  Laboratory  experiments  also  appeared  to  prove  that  winter 
frost,  or  winter  rest,  must  have  some  special  influence  which  disposes  the 
germ  to  develop  promptly  with  a  rise  of  temperature  in  spring,  while  later 
in  the  year  it  needs  more  warmth,  and  a  more  prolonged  period  of  such 
warmth. 

The  escape  of  the  miasm  of  malaria  into  the  air  is  probably  not  so  much 
due  to  the  effect  of  currents  of  atmospheric  air  aspirating  the  soil  as  to  the 
movements  of  the  ground  air  caused  by  differences  of  density.  Thus  the 
ground  air  tends  to  rise  into  the  atmosphere  more  particularly  towards  the 
evenmg  by  reason  of  its  rarity  as  compared  with  that  of  the  air  above,  and  it 
is  in  the  evening  and  at  night  in  summer  and  autumn,  when  the  atmosphere 
is  generally  polluted  with  ground  air,  that  malarial  infection  most  often  occurs, 
while  by  day,  when  there  might  be  supposed  to  be  more  exposure  to  malarial 
emanations,  infection  rarely  occurs.  Hence  also  the  germ  cannot  be  present 
in  the  dust  at  the  surface  of  the  earth,  but  rather  contained  by  the  gi'ound  air 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  349 

below  the  surface.  Confirmation  of  this  is  found  in  the  fact  that  in  malarious 
regions  the  digging  up  of  the  soil  has  frequently  caused  an  epidemic  of 
malaria  among  those  employed  in  the  work  of  excavation. 

Obstructions  to  the  outflow  of  the  ground  water  in  malarious  soils,  as 
occurred  during  the  construction  of  the  Ganges  and  the  Jumna  Canals,  in 
which  the  outflow  of  a  large  tract  of  country  was  impeded,  have  often  been 
followed  by  widespread  malarial  epidemics.  Both  in  India  and  in  the  United 
States  it  has  also  been  noticed  that  obstruction  to  the  natural  drainage  caused 
by  the  blocking  of  watercourses  by  mills  and  dams  has  been,  at  any  rate  in 
part,  the  cause  of  severe  and  fatal  outbreaks  of  the  disease.  A  rapid  rise  in 
the  ground-water  level  may  follow  on  an  exceptional  rainfall,  particularly  if 
the  outfall,  though  sufficient  in  comparatively  dry  weather,  is  inadequate  for 
carrying  ofl'  an  amount  of  water  much  in  excess  of  the  usual  amount.  Such 
an  instance  occurred  at  Kurrachee,  in  Scinde,  where  the  ground  is  flat  and 
there  is  no  subsoil  drainage,  but  where,  as  the  rainfall  is  usually  small,  and 
the  ground  dries  fast,  an  epidemic  of  malaria  is  an  event  almost  unknown. 
An  unprecedented  fall  of  rain  in  1869  was,  however,  followed  by  so  widespread 
an  outbreak,  that  the  regiment  which  was  stationed  there  at  the  time  had 
to  be  embarked  for  Madras,  as  every  man  had  been  attacked,  although  fortu- 
nately the  disease  had  not  been  present  in  a  very  fatal  form. 

Conversely  the  lowering  of  the  subsoil  water  due  to  an  increased  outflow, 
the  result  of  extensive  drainage  operations,  has  in  many  places  brought  about 
a  remarkable  reduction  of  malarial  disease.  This  has  been  especially  notice- 
able in  England,  in  the  counties  of  Norfolk  and  Lincolnshire,  which  within 
comparatively  recent  times  were  noted  haunts  of  malaria,  but  where,  at  the 
present  day,  owing  to  the  reclaiming  by  systematic  drainage  of  large  areas  of 
marshy  country,  the  disease  has  practically  disappeared. 

Pettenkofer  relates  a  case  which  is  of  interest  as  showing  the  effect  of 
subsoil  drainage  on  a  form  of  fever  alUed  to  malaria  occurring  among  horses 
in  the  royal  stables  at  Munich.  Although  the  sanitary  arrangements  m 
each  of  the  two  stables  appeared  to  be  equally  good,  and  the  food,  accommo- 
dation, and  attendance  in  each  were  apparently  similar,  horses  sufi'ered  much 
more  severely  in  one  than  in  the  other.  The  disease  was  not  infectious,  as 
horses  removed  from  the  unhealthy  stable  did  not  communicate  the  disease 
to  those  in  the  more  healthy  one.  After  careful  investigation,  the  only  cir- 
cumstance that  could  be  found  to  account  for  the  difference  between  the  two 
places  was  that  whereas  in  the  case  of  the  healthy  stable  the  ground  water 
was  met  with  at  a  depth  of  between  5  and  6  feet,  at  the  site  of  the  unhealthy 
stable  it  rose  to  within  2^  feet  of  the  surface.  Deep  drainage  was  then  re- 
sorted to  in  the  latter  situation,  and,  the  level  of  the  ground  water  having 
been  reduced  to  the  same  point  as  at  the  healthy  site,  the  disease  disap- 
peared. 

Malarious  Soils 

The  soil  in  districts  in  which  malarial  fevers  are  prevalent  is  usually 
more  or  less  marshy,  or,  at  any  rate,  is  in  the  vicinity  of  extensive  marshes, 
although  there  are  occasional  exceptions  to  this  rule.  In  addition  to  being- 
saturated  with  moisture,  such  soils  also  contain  a  large  amount  of  decaying 
vegetable  matter,  and  the  air  above  may  hold  large  amounts  of  carbonic  acid, 
marsh  gas  (light  carburetted  hydrogen),  sulphuretted  hydrogen,  and  watery 
vapour,  while  suspended  in  it  may  be  found  debris  of  vegetable  and  animal 
organic  substances,  diatoms,  infusorise,  alg^,  and  various  micro-organisms. 
These,  which  are  all  in  the  first  instance  derived  from  the  soil,  doubtless  in- 
clude the  particular  agent  to  which  the  propagation  of  the  disease  is  due^ 


.350  HYGIEXE 

but  it  is  quite  possible  that  other  of  the  constituents  of  air  or  soil  may,  by 
their  effect  on  the  system,  predispose  to  the  attack  of  the  malarial  organism. 
Thus  it  has  been  supposed  that  the  sulphuretted  hydrogen  which  is  evolved 
in  great  quantities  from  marshes  in  certain  districts,  may  give  rise  to  symptoms 
■of  ana-mia  and  prostration,  -which  not  unfrequently  accompany  malarial 
poisoning.  As  to  the  exact  chemical  conditions  of  soil  which  favour  the 
production  of  malaria,  but  little  is  at  present  known,  as  exact  chemical 
estimations  have  not  been  systematically  carried  out,  but  there  can  be  little 
doubt  that  the  inorganic  constituents  of  the  soil  have  little  or  nothing  to  do 
Avith  the  problem-,  since  in  difl'erent  parts  of  the  world  malaria  is  found  to 
prevail  on  soils  which  range  from  the  most  impervious  forms,  such  as  even 
granite,  to  the  loosest  forms  of  sand. 

The  large  amount  of  vegetable  matter  found  in  some  malarial  soils, 
amounting  to  about  30  per  cent,  in  the  case  of  the  Tuscan  Maremma,  and 
possibly  even  more  in  other  districts,  gives  rise,  during  putrefaction,  to  various 
organic  acids,  named  humic,  ulmic,  crenic,  and  apocrenic,  of  the  exact 
chemical  constitution  of  which  there  is  at  present  but  little  known,  and  it 
may  be  that  these  may  exert  a  deleterious  influence  on  health,  either  by 
being  carried  by  air  or  water.  In  some  cases  the  process  of  decomposition 
of  the  vegetable  forms  is  one  which'  extends  over  an  almost  unlimited  time, 
plants  having  been  found  still  undestroyed  in  marshy  districts  where  the 
same  conditions  have  prevailed  for  centuries. 

The  influence  of  vegetable  decomposition  in  helping  to  give  rise  to  attacks 
of  ague  is  well  seen  in  an  instance  quoted  by  Friedel.  He  mentions  that  in 
the  Marine  Hospital  at  Swinemiinde,  near  Stettin,  patients  who  were  placed 
in  a  certain  convalescent  ward  invariably  contracted  a  bad  attack  of  tertian 
ague  after  a  residence  there  of  two  or  three  days.  No  cases  occurred  in  any  of 
the  other  wards,  and  the  curious  incidence  of  the  disease  leading  to  a  thorough 
investigation,  it  was  found  that  outside  the  windows  of  the  affected  ward 
was  a  large  rain-water  cask  full  of  rotten  leaves  and  brushwood.  Water  had 
overflowed  from  the  cask  and  formed  a  large  stagnant  pool  alongside  the  ward 
into  which  effluvia  had  freely  found  their  way,  particularly  when  in  the  hot 
weather  all  doors  and  windows  were  kept  open  at  night.  This  state  of  aflairs 
having  been  attended  to,  the  ward  in  course  of  time  lost  its  evil  reputation. 
It  is  not,  of  course,  suggested  that  vegetable  effluvium  is  of  itself  sufficient  to 
cause  an  attack  of  malaria,  but  evidently  there  were  present  in  this  instance 
circumstances  which  would  be  exceptionally  favourable  for  the  development 
of  the  particular  organism  immediately  concerned. 

On  the  other  hand,  ague  of  a  most  virulent  form  has  been  met  with  in 
districts  which  appeared  to  be  perfectly  dry  and  arid,  thus  showing  that  the 
presence  of  decomposing  vegetable  matters  is  not  essential.  Thus,  according  to 
Hirsch,  the  tableland  of  Castile,  the  plain  of  the  Araxes,  and  the  lofty  plateaux 
of  Northern  India  and  Persia  are  all  highly  malarial,  and  even  in  Italy 
careful  inquiry  has  apparently  proved  that  some  malarial  districts  are  in  con- 
siderable i^art  devoid  of  water  and  sterile.  We  have  it  also  on  the  authority 
of  Dr.  William  Ferguson,  nearly  a  century  ago,  that  he  had  observed  in- 
stances in  which  British  troops  were  attacked  with  the  disease  while  encamped 
upon  dry  sandy  soils,  both  in  Holland  and  in  Spain.  Friedel  and  Maclean 
have  laid  stress  on  the  development  of  malaria  in  Hong  Kong  and  other 
places  situated  on  hard  rock  {granitic  and  metamorphic),  particularly  where 
these  have  become  weathered  and  disintegrated,  but  in  such  districts  it  is 
quite  possible  that  it  is  not  dependent  so  much  on  the  actual  disintegra- 
tion of  the  granite  as  upon  the  abundant  cryptogamic  vegetation  which  is 
found  in  the  soil  filling  up  the  clefts  in  the  rock.     In  many  instances  also  in 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  351 

Avhicli  malaria  lias  shown  itself  in  places  where  the  soil  was  apparently  free 
from  moisture,  water  may  have  been  present,  even  in  considerable  quantity 
in  the  lower  layers  of  the  soil,  especially  where  a  substratum  of  clay  or  other 
impermeable  material  existed,  the  soil  being  only  saturated  up  to  a  certain 
level. 

Although  malarious  diseases  are  doubtless  most  prevalent  in  the  neigh- 
bourhood of  marshes,  these  may  exist  even  over  considerable  areas  without 
paludal  fevers  making  their  appearance.  This  is  notably  the  case  in  countries 
like  Ireland,  which  are  widely  covered  with  peat  bogs,  but  where  malaria  is  not 
at  all  abundant.  Moreover,  marshes  which  are  regularly  overflowed  by  salt 
water  do  not  breed  the  disease,  notwithstanding  that  their  surface  is  exposed 
for  a  large  part  of  each  day.  Even  in  marshes  not  exposed  to  the  action  of 
the  sea,  investigations  have  shown  that  malaria  is  often  not  developed  during 
the  wet  part  of  the  year,  when  the  ground  is  entirely  flooded  with  water,  but 
rather  during  those  seasons  at  which  large  parts  of  it  are  exposed  to  the  air 
and  so  become  more  or  less  dry.  On  the  other  hand,  in  Italy  it  has  been 
noticed  that  occasionally  the  overflowing  of  fresh -water  marshes  by  the  sea 
has  caused  a  considerable  development  of  malaria,  but  obviously  the  condi- 
tions are  different  to  those  which  obtain  in  the  case  of  a  daily  flushing  by  the 
tide. 

Many  alluvial  soils,  particularly  those  which  have  been  recently  formed, 
give  out  malaria,  even  though  they  may  not  be  marshy.  This  may  be  due 
to  the  fact  that  they  contain  more  organic  matter,  which  would  be  especially 
likely  to  be  the  case  where  they  occur  in  the  vicinity  of  streams,  as  along  the 
estuaries  and  deltas  of  rivers  which  are  for  the  most  part  only  occasionally 
■covered  with  water.  In  all  such  situations,  hoAvever,  the  malarial  poison  is 
strictly  localised,  the  interposition  of  a  belt  of  trees  or  of  a  sheet  of  water 
being  sufficient  to  protect  the  inhabitants  of  neighbouring  districts  from 
its  influence.  Thus,  when  English  troops  occupied  Walcheren  and  other 
parts  of  Holland,  it  was  several  times  noticed  that  only  those  soldiers  who 
disembarked  were  attacked  by  ague,  those  who  remained  on  board  ship,  even 
when  in  narrow  channels,  escaping. 

Certain  sandy  soils,  especially  when  impregnated  with  a  large  proportion 
of  iron,  have  been  reputed  to  be  extremely  malarious,  but  the  influence  of 
the  iron  in  this  connection  is  more  than  doubtful,  the  supposed  effect  having 
more  probably  to  be  sought  in  the  presence  of  organic  matters,  which  are 
often  found  in  large  amount,  as  in  the  sandy  soil  of  the  Laudes,  in  south- 
west France. 

The  Bacillus  and  Plasmodium  Malarics 

From  the  evidence  that  has  been  brought  forward,  it  appears  certain  that 
there  is  a  very  close  relation  between  certain  soil  conditions  and  the  occur- 
rence of  malarial  disease,  and  consequently  numerous  observers  have  sought 
for  the  presence  in  malarious  soils  of  some  organism  which  might  possess 
the  power  of  transmitting  the  disease.  Klebs  and  Tommasi-Crudeh,  while 
engaged  on  such  a  series  of  experiments,  found  in  the  soil  of  the  Roman 
Campagna  a  distinctive  bacillus  which  they  beheve  to  be  the  specific  cause 
of  malaria.  The  bacillus,  which  varies  considerably  in  size,  up  to  the  diameter 
of  a  red  corpuscle  of  the  blood,  grows  in  artificial  cultures  into  twisted 
threads ;  inoculated  into  rabbits  it  is  stated  to  produce  a  febrile  disorder  ana- 
logous to  malarial  fever,  while  threads  and  spores  may  be  found  in  abundance 
in  the  spleen  and  marrow.  Marchiafava  has  described  bacilh  with  end- 
spores  as  occurring  in  the  blood  of  patients  suffermg  from  malaria. 


352  HYGIENE 

The  latter  observer,  however,  in  connection  with  CelH,  has  more  recently 
found  that  pecuhar  amoeboid  bodies  (plasmodia),  occasionally  showing  motile 
filaments,  and  often  containing  granules  and  black  pigment  masses,  are 
constantly  to  be  found  in  the  blood  in  cases  of  malaria,  either  free  or  enclosed 
within  the  red  corpuscles.  These  organisms  are  probably  allied  to  the  flagel- 
lated protozoa. 

Although  general  interest  in  this  subject  was  perhaps  first  roused  by  the 
publications  of  Marchiafava  and  Celli,  who  gave  the  name  Plasmodmm 
vialarice  to  the  organism  they  found  in  the  blood,  it  had  been  previously 
described  by  Laveran  in  Algiers  in  papers  communicated  by  him  to  the  Paris 
Academy  of  ^Medicine  in  1881  and  1882,  his  researches  being  finally  embodied 
in  a  large  work  which  he  published  on  the  malarial  fevers.  He  found  as 
characteristic  elements  in  the  blood  of  persons  attacked  with  malaria,  (1) 
crescentic  pigmented  bodies,  (2)  pigmented  bodies  in  the  interior  of  red  cor- 
puscles, which  underwent  changes  in  form,  described  as  amosboid,  and  (3)  a 
pigmented  flagellate  organism.  He  looked  upon  all  these  forms  as  phases  in 
the  development  of  an  infusorial  organism  which  he  regarded  as  the  germ  of 
the  disease.  These  observations  have  subsequently  been  for  the  most  part 
confirmed  by  Kichards,  Councilman,  and  Osier. 

Mosso,  however,  has  sought  to  prove  that  these  bodies  resolve  themselves 
into  degenerative  types  of  the  red  blood-corpuscles,  in  which  he  is  su  )ported 
by  Tommasi-Crudeli,  who  regards  the  forms  in  question  as  the  result  rather 
than  the  cause  of  malarial  disease,  and  who,  moreover,  still  maintains  the 
pathogenic  nature  of  the  bacillus  discovered  by  Klebs  and  himself.  Von 
Taksch  states  that  he  has  many  times  examined  the  blood  of  patients 
suflering  from  intermittent  fever,  without  ever  finding  such  bodies  as  those 
described  by  Marchiafava,  Celli,  and  others  ;  but  against  such  merely  negative 
results  may  be  placed  the  experience  of  Osier,  who  examined  seventy  cases 
of  this  disease,  in  not  one  of  whom  did  he  fail  to  find  the  plasmodium.  It 
would  appear  from  his  researches,  hoAvever,  that  the  organisms  concerned 
assume  a  greater  variety  of  forms  than  was  previously  supposed,  which  may 
possibly  account  for  them  having  been  overlooked  in  some  instances. 

Yet  another  organism  has  been  described  by  Sakharoff  as  being  present 
in  the  blood  of  malarial  patients.  This  parasite,  which  may  attain  enormous 
proportions,  as  large  as  twenty  corpuscles  together  or  even  larger,  consists  of  a 
mass  of  extremely  fine  protoplasm  containing  numerous  dark  roundish  sharp - 
coloured  motile  granules  and  a  greyish  nucleus  about  the  size  of  two  blood- 
corpuscles.  The  hgematozoon  is  capable  of  transformation  into  a  number 
of  bright  homogeneous  clear  bodies,  which  are  formed  by  the  separating  off 
of  protoplasmic  processes.  In  course  of  time  some  of  them  penetrate  into 
the  red  corpuscles,  increase  in  size,  develop  pigment  granules,  and  gradually 
pass  into  the  adult  form  mentioned  above  ;  while  other  bodies  having  a 
smaller  size  coalesce  to  form  threads  closely  resembling  the  spirochetre  of 
relapsing  fever,  differing  only  from  the  latter  in  their  being  somewhat  thicker, 
and  in  their  performing  comparatively  slower,  wave-like  movements.  The 
intracorpuscular  form  he  beheves  to  be  identical  with  Laveran's  malarial 
parasite. 

It  will  be  seen  from  so  many  contradictory  statements  that  the  question 
as  to  what  is  the  specific  cause  of  intermittent  fever  is  not  yet  satisfactorily 
solved.  Even  supposing  that  these  amoeboid  forms  are  invariably  present,  the 
question  arises.  Are  they  pathogenic  or  are  they  merely  associated  with  the 
disease,  which  in  some  way  furnishes  conditions  favourable  to  their  growth  ? 
As  evidence  of  their  pathogenic  nature  may  be  urged  the  constancy  of  their 
presence,  their  absence  from  other  healthy  individuals  in  malarial  regions^ 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  353 

their  destructive  influence  on  the  blood-corpuscles,  and  their  abundance  in 
many  of  the  graver  forms  of  the  disease.  80  far  the  presence  of  these  bodies 
has  not  been  demonstrated  hx  soil,  nor  have  they  yet  been  cultivated  outside 
the  human  system,  but  by  inoculation  and  the  intravenous  injection  of 
malarial  blood  containing  them,  Marchiafava  and  Celli  have  succeeded  in 
communicating  the  disease  to  other  individuals  ;  but  in  regions  where  malaria 
is  prevalent  such  experiments  cannot  but  be  looked  upon  with  suspicion.  It 
should,  however,  be  remembered  that  h^ematozoa  are  not  uncommon  in 
animals,  and  as  in  the  rat  do  not  appear  to  interfere  seriously  with  the  health 
of  their  host.  Under  these  circumstances  the  association  of  a  specific  form 
with  a  definite  disease  in  an  animal  makes  it  all  the  more  probable  that  the 
species  is  pathogenic  (Osier). 

Golgi  has,  moreover,  recently  attempted  to  prove  that  the  paroxysms  of 
intermittent  fevers  bear  a  direct  relation  to  the  development  of  generations 
of  parasites,  and  that  the  different  developmental  periods  of  different  broods 
are  the  conditions  determining  the  varying  periodicities  of  the  recognised 
varieties  of  malaria.  He  claims  that  the  experienced  observer  can  distinguish 
by  biological  and  morphological  characteristics  those  organisms  which  have 
a  life-cycle  corresponding  with  the  periodicity  of  tertian  ague  from  those  in 
which  the  cycle  corresponds  with  the  quartan  variety  of  malarial  fever.  The 
endoglobular  amoeboid  bodies  found  in  tertian  fever  show  much  more  active 
movements  than  those  of  the  quartan  form,  in  which  latter  these  amoeboid 
changes  can  only  be  distinctly  observed  in  the  first  stage  of  their  development, 
and  never  very  readily,  it  being  usually  necessary  to  warm  the  preparation  in 
order  to  excite  them.  In  quartan  fever  the  affected  corpuscles  are  stated  to 
become  shrunken,  but  to  retain  their  colour  in  great  degree  up  to  the  latest 
phase  in  their  destruction ;  while  in  tertian  fever,  on  the  other  hand,  the 
parasite  which  completes  its  developmental  cycle  in  two  days,  as  opposed  to 
three  days  in  the  quartan  form,  decolourises  in  an  energetic  and  rapid 
manner  the  red  blood-corpuscles,  which,  however,  retain  their  regular  outline, 
appearing  in  some  ca,ses  even  larger  than  normal.  Finally,  the  author 
relates  a  case,  the  obscure  clinical  features  of  which  were  explained  by  his 
discovery  in  the  blood  of  the  organisms  peculiar  to  both  quartan  and  tertian 
fever,  those  of  the  former  variety  being  most  numerous. 

Should  further  research  confirm  these  observations,  there  can  no  longer 
be  any  doubt  that  these  parasitic  organisms  play  a  most  important  part  in 
the  astiology  of  malarial  fevers,  and  seeing  that,  even  at  the  present  time,  such 
connection  appears,  to  say  the  least,  more  than  probable,  it  is  highly  desirable 
that  attention  should  be  turned  to  the  more  thorough  understanding  of  the 
Ufe-history  of  the  Plasmodium  malaricB  and  particularly  to  the  question  as 
to  whether,  under  certain  conditions,  it  is  capable  of  living  and  perhaps  of 
multiplying  in  the  soil  of  districts  favourable  to  the  development  of  the  disease, 
and  also  to  those  circumstances  which  either  encourage  or  are  inimical  to  its 
development  in  the  body.  Pending  more  exact  knowledge,  however,  in  this 
drection,  there  remain  other  factors  in  the  causation  of  malaria  which  must 
not  be  lost  sight  of,  as  by  due  attention  to  them  much  may  be  done  in  pre- 
venting the  appearance  or  diminishing  the  virulence  of  the  disease. 

Among  such  preventive  measures  must  be  mentioned  thorough  and  deep 
drainage,  by  which  the  subsoil  water  is  permanently  lowered  and  stagnant 
sheets  of  water  caused  to  disappear.  The  nature  of  the  soil  also  should  be 
inquired  into,  and  if  found  to  contain  much  organic  matter  houses  built  upon 
it  should  be  protected  by  a  layer  of  concrete  underneath,  to  prevent  the 
upward  passage  of  the  ground  air  ;  while  even  greater  security  in  this  direction 
may  be  obtained  by  raising  buildings  off  the  ground  on  a  series  of  arches. 

VOL.   I.  A  A 


354  HYGIENE 

Malarial  efflu\-ium  being  most  dangerous  at  niglit,  jt  is  well  also  that  the 
sleeping  rooms  should  be  placed  at  the  upper  part  of  houses,  as  it  does  not 
appear  to  rise  beyond  a  certain  height  from  the  ground.  Seeing  that  the 
presence  of  much  vegetable  debris  either  in  the  soil  or  upon  it,  especially 
when  accompanied  by  a  certain  amount  of  moisture  and  a  warm  temperature, 
tends  to  favour  the  development  of  the  malarial  agent,  it  is  of  importance  to 
remove  all  masses  of  decaying  vegetation  and  at  the  same  time  prevent 
putrefactive  changes  of  the  soil  by  providing  an  outlet  for  the  Avater,  either 
as  already  suggested  by  efficient  drainage,  or  by  the  planting  of  trees,  which 
by  means  of  their  leaves  throw  off  enormous  quantities  of  water  in  the  course 
of  the  day.  This  is  specially  the  case  with  the  Eiicahjptus  globulus,  which 
is  supposed  to  be  capable  of  absorbing  and  evaporating  eleven  times  the 
rainfall  over  the  area  it  covers.  Next  m  value  from  this  point  of  view  comes 
the  oak  ;  so  that  it  is  highly  desirable  that  one  or  the  other  of  these  trees 
should  be  planted  freely  in  malarious  districts.  Where  this  has  been  already 
done,  considerable  effect  in  the  direction  of  rendering  the  locality  more  healthy 
has  been  observed,  as  wh.ai  moisture  is  removed  from  the  soil  the  malarial 
organism  no  longer  finds  its  surroundings  favourable  for  development.  Sun- 
flower plants  have  a  similar  effect,  but  of  course  in  less  degree.  Occasionally 
great  benefit  has  been  derived  from  covering  the  ground  with  grass,  which 
hinders  the  ascent  of  the  miasma  and  at  the  same  time  causes  the  evaporation 
of  a  considerable  amount  of  soil  moisture. 

Although  trees  are  valuable  both  by  aiding  removal  of  Avater  from  the 
soil  and  also  apparently  from  opposing  a  barrier  to  the  progress  of  malaria, 
the  same  cannot  be  said  of  thick  undergrowths  of  brushwood,  which  only 
hinder  a  proper  circulation  of  air,  and  at  the  same  time  favour  extensive 
decomposition.  A  remarkable  instance  of  this  is  seen  in  the  case  of  a  large 
area  of  maccliia  which  lay  between  the  town  of  Cisterna  and  the  Pontine 
Marshes.  In  1714  it  was  proposed  to  cut  it  down,  but  this  was  successfully 
opposed  by  Lancisi,  the  Papal  sanitary  adviser  at  the  time,  on  the  ground  that 
a  barrier  or  filter  was  thus  opposed  to  the  malarial  emanations  from  the  Pontine 
Marshes.  Cisterna  at  that  time  was  extremely  unhealthy,  and  had  a  rapidly 
diminishing  population  ;  but  when,  about  one  hundred  years  after,  these  woods 
were  cut  down,  the  health  of  the  place  at  once  commenced  to  improve,  and 
the  population  increased  by  rapid  strides. 

There  is  at  present  little  or  no  evidence  to  prove  that  malaria  can  be 
caused  by  drinking-water  alone,  since,  as  North  has  well  shown,  *  the  healthiest 
parts  of  the  city  of  Eome  are  supplied  by  water  admittedly  the  best  in  the 
world,  and  which  rises — to  take  the  Acqua  di  Trevi  or  Acqua  Vergine  as  an 
example — on  unenclosed  land,  in  springs  which  bubble  up  and  cover  the 
surface  in  a  locality  so  unhealthy  that  to  pass  several  nights  there  in  August 
might  involve  risk  to  life,  and  certainly  to  health.  There  seems  to  be  but 
little  doubt  that  a  supply  of  good  drinking-water  is  of  importance  in  malarious 
localities,  but  it  has  yet  to  be  shown  that  in  exchanging  pond  and  ditch 
water  for  that  of  springs  the  inhabitants  cease  to  take  a  poison  into  their 
bodies.  The  evidence  points  rather  to  the  fact  that  by  so  doing  they  raise 
their  general  health,  ai ,  \  so  become  less  liable  to  the  disease.  At  all  events, 
proof  that  the  malarial  infection  can  be  conveyed  by  water  is  wanting,  though 
very  largely  credited  by  the  natives  of  countries  where  the  disease  prevails.' 
At  the  same  time,  sur  ace  water  particularly  should  be  looked  upon  with 
suspicion  for  drinking  purposes,  and  if  only  shallow  wells  are  available  for 
the  necessary  supply,  it  is  well  that  it  should  be  boiled  before  being  taken 
into  the  system. 

Finally,  we  posses?   n  quinine  a  drug  which  exhibits  a  remarkable  pro- 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  355 

perty  in  enabling  the  body  to  withstand  malarial  attacks,  and  it  is  therefore 
only  prudent  to  make  constant  use  of  it  if  residence  in  or  passage  through 
countries  where  the  disease  is  prevalent  be  unavoidable. 

Eheumatism  and  Neuralgia 

It  is  probably  only  in  so  far  as  the  climate  of  a  locality  may  be  affected 
by  peculiarities  of  the  soil,  such  as  elevation,  configuration,  the  kind  of  rock, 
and  the  physical  characters,  that  we  have  to  take  this  factor  into  account  in 
the  aetiology  of  rheumatism.  Thus  it  is  well  known  that  the  disease  evinces 
a  preference  for  open  basins  and  plateaux  exposed  to  the  wind,  for  damp 
and  deeply  cleft  valleys,  and  for  sea-coasts  or  the  shores  of  great  rivers. 

Dampness  of  soil  may,  however,  predispose  to  this  disease,  from  the  fact 
that  it  renders  it  cold  ;  and  this  will  be  the  more  likely  to  be  the  case  at  low 
elevations,  and  where  there  is  an  impermeable  subsoil  such  as  clay ;  but  no 
sweeping  assertion  can  be  made  on  this  point,  as  the  necessary  data  for  the 
institution  of  the  comparative  frequency  of  the  disease  on  different  kinds  of 
soil  are  unfortunately  wanting. 

Neuralgia,  like  rheumatism,  is  doubtless  most  often  the  outcome  of  a  con- 
stitutional state  dependent  on  influences  from  without,  and  ultimately  trace- 
able to  the  circumstances  of  the  locality  or  of  the  season,  including  climate, 
weather,  and  soil ;  but  our  knowledge  of  the  geographical  distribution  of 
the  neuralgias  is  too  defective  to  let  us  decide  with  certainty  how  far  influ- 
ences of  the  latter  kind  may  determine  the  prevalence  of  the  malady  at 
various  parts  of  the  world  (Hirsch).  It  is  noteworthy,  however,  that  Valleia 
has  shown  that  neuralgias  of  the  rheumatic  kind  are,  along  with  other 
rheumatic  disorders,  commonest  within  the  temperate  zone  in  the  cold  and 
wet  seasons  of  the  year,  while  in  tropical  countries  they  reach  their  maximum 
when  the  rains  begin,  and  again  when  they  cease.  Foltz,  Lidell,  and  Gib- 
son have  also  called  attention  to  the  fact  that  those  states  of  soil  which  are 
favourable  to  malaria  may  also  predispose  to  neuralgia,  while  Hirsch  states 
that  Egypt  and  New  Caledonia,  which  are  remarkable  for  their  relative  or 
absolute  immunity  from  malarial  fevers  and  for  the  steadiness  of  their  climate 
and  weather,  are  strikingly  free  from  this  disease. 

Phthisis 

Tuberculosis,  or  phthisis,  is  a  micro-parasitic  and  possibly  infectious  dis- 
ease, which  has  been  proved  to  have  an  intimate  relation  to  dampness  of 
soil.  It  causes  an  average  of  50,000  deaths  annually  in  England  at  the 
present  time,  or  more  nearly  70,000  per  annum,  if  there  be  included  with  it 
deaths  registered  as  occurring  from  tabes  mesenterica,  tubercular  meningitis, 
and  '  other  forms  of  tubercular  disease  and  scrofula.' 

In  presenting  his  report  for  1858  to  the  President  of  the  General  Board 
of  Health,  Mr.  Simon,  referring  to  a  report  by  Dr.  Greenhow  on  the  pre- 
vention of  pulmonary  phthisis,  stated  that  '  pulmonary  affections,  including 
phthisis,  cause  very  nearly  a  quarter  of  the  annual  mortahty  of  England. 
Every  100,000  of  our  population  yields  on  an  average  552  annual  victims  to 
this  deadly  class  of  disorder.'  He  also  expressed  the  opinion  that  pulmonary 
phthisis  then  killed,  as  now,  on  an  average  more  than  50,000  persons 
annually  in  this  country ;  so  that,  although  the  total  population  has  enor- 
mously increased  since  that  time,  the  number  of  deaths  has  remained 
stationary.  This  improvement  is  shown  in  another  and  better  manner  by 
comparing  mortality  statistics  in  relation  to  death-rate  per  unit  of  popula- 
tion, as  in  the  following  table  extracted  from  the  Kegistrar-General's  Forty- 

aa2 


356 


HYGIEXE 


fifth  Annual  Eeport,  ^'liicli  shows  the  annual  mortality  per  million  from 
'  phthisis  '  at  all  ages,  and  at  certain  typical  ages  in  both  sexes  the  last  three 
decennia  : — 

Phthisis  Ml  England  and  Wales 


Tears 

All  ages 

15— 

20- 

25  — 

35- 

1851-60 
1861-70 
1871-80 

2,679 
2,475 
2,116 

2,961 
2,651 
2,036 

4,181 
3,928 
3.117 

4,317 
4,243 
3,619 

4,091 
4,026 
3,745 

As  a  result  of  his  investigation  Dr.  Greenhow  showed,  among  other 
things,  that  '  in  proportion  as  the  male  and  female  populations  are  severally 
attracted  to  indoor  branches  of  industry,  in  such  proportion,  other  things 
being  equal,  their  respective  death-rates  are  increased,'  the  evil  eflect  of  cer- 
tain industries,  of  faulty  ventilation,  and  of  overcrowding  being  also  shown 
to  exert  a  considerable  influence  in  inducing  the  disease.  Notwithstanding 
such  deleterious  influences,  however,  the  decrease  in  the  phthisis  death-rate 
has  been  fairly  continuous,  so  that  some  other  factor  must  have  come  into 
play  within  comparatively  recent  years. 

It  was,  hoAvever,  reserved  for  Dr.  Buchanan  to  bring  to  light  a  most 
important  and  unexpected  factor  in  the  aetiology  of  this  disease,  which  goes 
far  to  explain  the  reduction  in  the  death-rate  spoken  of  above.  In  1865-66 
he  undertook  an  inquiry,  the  object  of  which  was  to  ascertain  what  had  been 
the  results  obtained  by  local  authorities,  who  by  means  of  such  works  as 
water  supply  and  sewerage  had  attempted  to  improve  the  sanitary  condition 
of  the  districts  mider  their  control.  One  main  purpose  of  the  inquiry  was  '  that 
the  then  Central  Public  Health  Authority  should  fulfil  one  of  the  principal 
duties  expected  of  it  by  making  new  local  experiences  conducive  to  general 
enlightenment ;  '  and  this  object  was,  in  one  important  respect,  attained  in 
a  direction  which  is  best  shown  in  the  resume  of  the  subject  given  by  Mr. 
Simon  in  his  Annual  Eeport  for  1866.  He  there  says  :  '  These  columns,' 
referring  to  Dr.  Buchanan's  report,  '  appear  to  indicate  a  partial  dependence 
of  pulmonary  phthisis  on  some  of  the  unwholesome  conditions  which  have 
been  removed.  And  when  detailed  examination  is  made  of  the  cases  which 
give  that  indication,  and  they  are  compared  with  the  different  class  where 
phthisis  has  not  lessened  its  amount,  the  novel  and  most  important  conclu- 
sion suggests  itself  that  the  drying  of  soil  which  has  in  most  cases  accom- 
panied the  laying  of  main  sewers  in  the  improved  towns  has  led  to  the 
diminution,  more  or  less  considerable,  of  phthisis.  The  facts  which  are  yet 
in  evidence  seem  most  strongly  to  support  this  conclusion,  which,  should  it 
be  substantiated,  will  constitute  a  very  valuable  discovery  evolved  by  Dr. 
Buchanan  from  the  inquiries  here  reported  on.  ...  It  will  be  seen  that  the 
reduction  of  phthisis  where  certam  works  have  been  executed  is  far  too  large 
and  far  too  general  to  be  regarded  as  an  accidental  coincidence.  The  re- 
duction, namely,  on  the  death-rates  by  phthisis  in  the  first  fifteen  towns  in 
Dr.  Buchanan's  table  are  as  follows  :  Salisbury,  49  per  cent,  of  its  previous 
rate  ;  Ely,  47  per  cent. ;  Eugby,  43  ;  Banbury,  41 ;  Worthing,  36  ;  Maccles- 
field, 31 ;  Leicester,  32 ;  Newport,  32 ;  Cheltenham,  26 ;  Bristol,  22  ;  Dover, 
20 ;  Warwick,  19  ;  Croydon,  17 ;  Cardiff,  17  ;  Merthyr,  11.  And  the  fact 
that  in  some  of  these  cases  the  diminished  fatality  of  phthisis  is  by  far  the 
largest  amendment,  if  not  the  only  one,  which  has  taken  place  in  the  local 
health  becomes  extremely  interesting  and  significant  when  the  circumstance 
is  remembered  that  works  of  sewerage,  by  which  the  drying  of  the  soil  is 


TEE  INFLUENCE   OF  SOIL   ON  HEALTH  357 

effected,  must  always  of  necessity  precede,  an4  do  indeed  sometimes  precede 
by  years,  the  accomplishment  of  other  objects  (house-drainage,  abolition  of 
cesspools,  and  so  forth)  on  which  the  cessation  of  various  other  diseases  is 
dependent.  Thus,  as  regards  the  two  largest  populations  concerned  in  this 
question — those  of  Bristol  and  Leicester — no  doubt  the  comparative  smallness 
of  effect  hitherto  produced  on  the  general  and  diarrhooal  death-rates  of  these 
towns  may  (so  far  as  it  is  not  fallacious)  be  referred  to  the  shortness  of  time 
for  which  finished  constructions  have  been  at  work  for  the  detailed  dispol- 
lution  of  houses  and  their  dependencies  ;  but  a  reduction  already  of  a  sixth 
in  the  phthisis  mortality  of  Bristol  and  a  reduction  of  a  fourth  in  the  phthisis 
mortality  of  Leicester  are  apparently  connected  with  the  fact  that  in  both 
towns  main  sewerage  on  a  large  scale,  with  more  or  less  drying  of  soil,  has 
•existed  in  comparison  for  many  years.  And  Eugby,  which,  long  as  it  has 
been  at  work,  has  not  yet  succeeded  in  getting  rid  of  endemic  diarrhoea  and 
typhoid  fever,  shows  at  least  this  result  of  its  main  drainage  works,  that  its 
phthisis  mortality  has  fallen  43  per  cent.' 

In  his  report  for  the  following  year,  1867,  Mr.  Simon  adds  :  '  The  above 
facts,  though  not  enough  in  themselves  to  prove  as  certain  the  very  important 
setiological  relation  which  they  suggested,  were  at  least  amply  sufficient  to 
show  that  a  very  promising  line  of  inquiry  had  been  opened.'  In  consequence 
of  the  vast  importance  of  the  subject,  Dr.  Buchanan  had  continued  his  inves- 
tigation, and  given  the  results  at  which  he  had  arrived  in  a  report,  presenting 
an  elaborate  examination  of  the  distribution  of  phthisis,  as  compared  with 
variations  of  soil,  in  the  three  south-eastern  counties  of  England,  beyond  the 
limits  of  the  metropolis,  which  apparently  confirmed  beyond  all  question  the 
conclusion  previously  suggested,  that  dampness  of  soil  is  an  important  cause 
of  phthisis  to  the  population  living  upon  the  soil. 

The  reason  for  the  counties  of  Surrey,  Kent,  and  Essex  being  the  only 
■ones  included  in  the  investigation  was  that  the  Geological  Survey  of  England, 
although  at  that  time  advancing  to  completeness  in  its  records  of  the  great 
formations  of  the  country,  had  mapped  the  minute  surface  geology  in  these 
counties  only.  It  was  evident  that  surface  peculiarities  would  require  to  be 
'  taken  into  account  quite  as  much  as  the  great  divisions  of  the  geologist ;  that 
brick  earth,  drift  gravel,  river  alluvium,  and  the  like,  have  an  importance  in 
themselves  quite  apart  from  the  character  of  the  larger  formations  over  which 
they  lie.' 

The  three  south-eastern  counties,  therefore,  formed  the  only  area  where 
the  survey  then  afforded  materials  for  profitable  detailed  examination  of  the 
soil  as  affecting  the  health  of  residents  upon  it. 

The  inquiry  was  carried  out  by,  first,  ascertaining  the  true  phthisis-rate 
■of  the  population,  and  in  the  second  place  noting  the  numbers  of  the  popula- 
tion in  each  district  that  were  found  '  living  upon  various  kinds  of  soil  and 
under  various  topographical  conditions.'  The  results  of  these  two  separate 
lines  of  investigation  were  then  brought  together  and  statistically  com- 
pared. 

The  results  of  the  inquiry  are  shown  in  the  following  general  conclusions 
with  which  Dr.  Buchanan  summarised  his  report : — 

1.  Within  the  counties  of  Surrey,  Kent,  and  Sussex  there  is,  broadly 
speaking,  less  phthisis  among  populations  living  on  pervious  soils  than  among 
populations  living  on  impervious  soils. 

2.  Within  the  same  counties  there  is  less  phthisis  among  populations 
living  on  high-lying  pervious  soils  than  among  populations  hving  on  low- 
lying  pervious  soils. 

3.  Within  the  same  counties  there  is  less  phthisis  among  populations 


858  HYGIENE 

living  on  sloping  imperious  soils  than  among  populations  living  on  flat  im- 
pervious soils. 

4.  The  connection  between  soil  and  phthisis  has  been  established  in  this 

inquiry  : 

(a)  By  the  existence  of  general  agreement  in  phthisis  mortality  between 
districts  that  have  common  geological  and  topographical  features  of  a  nature 
to  aiiect  the  water-holding  quality  of  the  soil. 

{b)  By  the  existence  of  a  general  disagreement  between  districts  that 
are  differently  circumstanced  in  regard  of  such  features. 

(c)  By  the  discovery  of  pretty  regular  concomitancy  in  the  fluctuation  of 
the  two  conditions — from  much  phthisis  with  much  wetness  of  soil  to  httlo 
phthisis  with  little  wetness  of  soil. 

(d)  By  the  observation  that  phthisis  has  been  greatly  reduced  in  towns 
where  the  water  of  the  soil  has  been  artificially  removed,  and  that  it  has  not 
been  reduced  in  other  towns  where  the  soil  has  not  been  dried. 

5.  The  whole  of  the  foregoing  conclusions  combine  into  one,  which  may 
now  be  affirmed  generally,  and  not  only  of  particular  districts,  that  wetness  of 
soil  is  a  cause  of  phthisis.  .  .  . 

6.  No  other  circumstance  can  be  detected,  after  careful  consideration  of 
the  materials  collected,  that  coincides  on  any  large  scale  with  the  greater  or 
less  prevalence  of  phthisis,  except  the  one  condition  of  soil. 

Dr.  Buchanan  had  not  long  completed  his  investigations,  when  it  became 
known  in  England  that  Dr.  Bowditch,  of  Boston,  U.S.,  had  been  working  on 
similar  lines  in  America  for  some  time  previously,  and  that  he  had  arrived 
at  identical  conclusions.  In  an  address  dehvered  at  the  annual  meeting  of 
the  Massachusetts  Medical  Society  in  18G2,  and  afterwards  pubhshed,  he  drew 
attention,  and  not  for  the  first  time,  to  the  remarkable  inequality  with  which 
he  found  phthisis  to  be  distributed  in  the  States,  and  to  the  connection  of 
this  inequality  with  differences  of  moisture  of  soil,  and  he  submitted  the  two 
following  propositions  as  containing  the  essential  results  of  a  very  extended 
inquiry  : — 

'  First :  A  residence  in  or  near  a  damp  soil,  whether  that  dampness  be 
inherent  in  the  soil  itself  or  caused  by  percolation  from  adjacent  ponds, 
rivers,  meadows,  marshes,  or  springy  soils,  is  one  of  the  principal  causes  of 
consumption  in  Massachusetts,  probably  in  New  England,  and  possibly  in 
other  portions  of  the  globe. 

'  Second  :  Consumption  can  be  checked  in  its  career,  and  possibly — nay 
probably — prevented  in  some  instances  by  attention  to  this  law.' 

He  not  only  proved  apparently  '  that  dampness  of  the  soil  of  any  township 
or  locality  is  intimately  connected,  and  probably  as  cause  and  effect,  with  the 
prevalence  of  consumption  in  that  township  or  locality,'  but  even  also  adduced 
particular  instances  as  tending  to  prove  that  '  some  houses  may  become  foci 
of  consumption  when  others,  but  slightly  removed  from  them  but  on  a  drier 
soil,  almost  wholly  escape.' 

Although,  therefore,  the  priority  of  discovermg  a  connection  between  soil- 
dampness  and  the  phthisis  rate  is  midoubtedly  due  to  Dr.  Bowditch,  the 
investigations  of  Dr.  Buchanan  are  none  the  less  valuable,  he  having  quite 
independently,  and  probably  upon  more  complete  data,  established  the  preva- 
lence of  a  similar  relation  in  this  country  ;  and,  indeed,  the  researches  of  both 
observers  obtain  additional  weight  from  the  fact  that  they  were  arrived  at 
almost  simultaneously,  each  observer  being  entirely  unbiassed  by  the  other. 

It  is  also  worthy  of  note,  as  affording  still  further  support  to  the  results 
thus  obtained  both  in  England  and  America,  that  the  Eegistrar-General  for 
Scotland  m  his  Seventh  Annual  Report,  adverting  to  Dr.  Bowditch's  work^ 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  359 

stated  that,  in  liis  opinion,  the  phthisis  mortahty  statistics  in  Scotland 
furnished  evidence  to  the  same  general  effect :  among  the  principal  towns, 
Leith  and  Edinburgh,  the  most  Ire.e  from  consumption,  having  also  the  driest 
sites,  while,  on  the  other  hand,  Glasgow  and  Greenock,  the  most  ravaged  by 
this  disease,  were,  beyond  all  comparison,  situated  on  the  dampest  sites.  The 
remarkable  freedom  from  consumption  of  the  Capo  of  Good  Hope  and  South 
Africa  generally,  as  also  of  Egypt,  as  compared  with  the  comparatively  high 
mortality  from  it  in  the  moist  climate  of  Great  Britain,  is  a  fact  which  also 
points  in  the  same  direction.  It  has  been  shown,  moreover,  in  America,  by 
Dr.  Andrews,  that  cases  of  phthisis  are  most  abundant  near  the  sea,  and 
diminish  with  increasing  distance  from  it,  so  that  while  in  Central  North 
America  the  proportion  of  deaths  from  consumption  to  deaths  from  all  causes 
is  least,  the  ratio  gradually  rises  as  we  pass  towards  either  the  Atlantic  or 
Pacific  Ocean,  the  numbers  being,  however,  greater  on  the  eastern  than  on 
the  western  coast,  while  on  the  northern  sea-boards  there  is  a  similar  increase 
over  districts  situated  more  towards  the  south. 

Hence  we  may  fairly  consider  the  proposition  affirming  a  close  relation 
between  tubercular  disease  and  moisture  of  locality  to  be  of  practically  uni- 
versal application. 

A  certain  amount  of  opposition  has,  however,  been  offered  to  these  views, 
notably,  by  Dr.  Charles  Kelly,  who,  in  his  Eeport  for  1879,  on  the  Combined 
Sanitary  District  of  West  Sussex,  has  thrown  doubt  on  these  conclusions, 
basing  his  statements  on  certain  data  collected  within  that  rural  area.  He 
there  states  that,  although  the  phthisis  death-rate  had  been  distinctly  low- 
ered during  immediately  preceding  years,  there  had  been  no  contemporary 
improvements  in  the  system  of  drainage  of  the  soil  to  account  for  the  altera- 
tion. Dr.  Thorne  Thorne,  on  the  other  hand,  has  indicated  that  the  large 
amount  of  agricultural  drainage  which  had  then  already  been  effected  through- 
out the  kingdom  had  been  of  a  sort  to  produce  a  similar  result  in  rural 
districts  to  that  brought  about  by  sanitary  drainage  in  towns,  and  he  at  the 
same  time  calls  attention  to  the  fact  that  Dr.  Kelly  offers  no  explanation  of 
the  striking  and  definite  relation  shown  by  Dr.  Buchanan  to  have  existed 
between  the  amount  of  diminution  of  phthisis  death-rate  and  the  extent  and 
permanence  of  the  lowering  of  subsoil  water.  In  the  same  report  Dr.  Kelly 
states  his  belief  that  a  number  of  changes,  social  as  well  as  sanitary,  includ- 
ing among  them  the  improved  state  of  the  cottages,  the  rise  of  wages  leading- 
to  the  children  being  better  clothed  and  fed,  the  increase  in  railway  com- 
munication, which  tends  to  diminish  intermarriage  and  to  cause  more  in- 
terchange of  population,  have  all  had  their  share  in  the  undoubted  improve- 
ment which  has  taken  place. 

In  a  later  report  (1887)  Dr.  Kelly  again  returns  to  the  subject,  and  gives 
a  series  of  comparison  tables  for  the  ten  years  1876-86  relating  to  the  com- 
bined district  of  West  Sussex.  He  first  classifies  the  different  soils  into  three 
classes  : — 

1.  The  pervious  soils,  which  include  the  upper  and  lower  green  sands,  the 
chalk,  and  the  lower  Tunbridge  Wells  sands. 

2.  The  retentive  soils,  which  include  the  Weald  clay,  the  clayey  beds  of 
the  lower  green  sand,  and  the  gault. 

3.  The  vioderately  pervious  soils,  including  a  long  strip  of  nearly  level 
land  between  the  South  Downs  and  the  sea,  where  the  chalk  is  covered 
for  a  depth  of  fifteen  to  fifty  feet  with  loam  and  brick  earth.  The  surface 
of  this  soil  rises  gently  from  the  sea  towards  the  Downs,  so  that,  although 
in  some  parts  the  clays  are  retentive,  yet  the  slope  towards  the  sea  enables 
surface  water  to  flow  away  readily,  except  in  some  of  the  low-lying  brooklands. 


3G0 


HYGIENE 


This  classification  is  followed  by  a  table  showing  the  various  death-rates 
on  these  different  soils  : — 


Nature  of  soil 

Population 

1876-86 
Death-rate  per  1,000,000  living  at  all  ages  from 

Phthisis 

Lung  diseases 

All  causes 

Pervious  . 
Moderately  pervious 
Ketentive . 

West  Sussex    . 

33,820 
29,640 
23,530 

86,990 

1,514 
1,467 
1,542 

1,506 

2,131 
1,892 
2,583 

2,172 

14,852 
14,463 
14,942 

14,741 

These  figures  appear  to  show  that  the  mortality  from  lung  diseases  varies 
considerably,  being  much  higher  or  retentive  than  on  porous  soils,  while 
the  mortahty  from  what  is  now  registered  as  phthisis  and  from  all  causes  is 
very  nearly  the  same  on  each  variety  of  soil. 

It  should,  however,  be  remembered  that  in  this  West  Sussex  district,  as 
indeed  thi-oughout  EDgland,  there  has  been  a  great  reduction  in  the  phthisis 
mortality  since  Dr.  Buchanan's  inquiry  into  the  subject  for  the  decade 
1851-60.  Moreover,  the  assumption  runs  through  all  Dr.  Kelly's  arguments 
that  the  relative  wetness  of  soil  in  the  six  registration  districts  with  which  he 
is  concerned  remams  in  later  times  as  it  was  in  1851-60.  What  his  statistics 
may  be  taken  to  show  is  that,  all  the  varieties  of  soil  being  now  equally 
healthy,  the  cause  of  the  phthisis  deaths  which  still  occur  has  to  be  sought  for 
in  some  other  direction. 

Not  a  particle  of  evidence  is  adduced  on  this  point,  nor  is  the  operation 
of  sanitary  measures  upon  the  soil  in  the  several  districts  even  spoken  of. 
In  his  Sixth  Annual  Keport  (1879),  indeed,  it  is  stated  that  there  has  been 
*  no  change  whatever  in  the  drainage  '  of  these  rural  districts,  but  this  state- 
ment is  too  bald  to  be  of  much  import.  The  assumption,  too,  pervades 
his  argument  that  soil  wetness  is  the  cause  of  phthisis,  whereas  all  that  has 
ever  been  claimed  for  it  in  this  connection  is  that  it  is  a  cause. 

The  relations  of  phthisis  to  season  and  temperature  are  somewhat  obscure, 
as  might  be  expected,  seeing  that  the  duration  of  the  disease  may  extend  over 
not  only  months,  but  years.  Buchan  and  Mitchell,  however,  have  shown 
that  mortality  from  tabes  shows  a  definite  relation  to  the  temperature,  the 
maximum  extending,  like  that  of  summer  diarrhoea,  from  the  middle  of  July 
to  the  middle  of  September,  while  the  absolute  minimum  is  foimd  by  them 
to  last  from  the  end  of  December  to  the  beginning  of  February. 

According  to  these  observers,  also,  a  curve  of  the  seasonal  relations  of 
phthisis  mortality  shows  that  '  the  absolute  minimum  occurs  in  the  last  week 
of  September,  after  which  it  begins  steadily  to  rise  ;  in  the  middle  of  November 
it  rises  still  more  rapidly  ;  during  the  last  three  weeks  of  December  it  falls 
a  Httle  ;  rises  again  in  the  beginning  of  the  year,  and  remains  steady  until 
the  second  week  of  March,  when  it  rises  to  the  annual  maximum  during 
March,  April,  and  May.  From  the  middle  of  July  to  the  middle  of  November 
it  is  below  the  average.  This  is  one  of  the  most  constant  curves  in  its  main 
features  from  year  to  year.' 

The  Bacillus  Tuberculosis 
To  Koch  is  undoubtedly  due  the  honour  of  having  discovered  the  micro- 
parasite  which  is  pathognomonic  of  the  disease  under  consideration.  Prior 
to  the  pubhcation  of  his  researches,  indeed,  numerous  observers  had  described 
various  micrococci  and  other  organisms  which  they  had  found  in  tuberculous 
material,  but  their  significance  has  not  been  confirmed  by  subsequent  re- 
search. 


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THE  INFLUENCE   OF  SOIL   ON  HEALTH  361 

According  to  Koch,  the  tubercle  bacilli  appear  in  the  form  of  rods,  the 
length  of  which  is  usually  equal  to  that  of  half  a  red  blood-corpuscle,  although 
this  may  vary  somewhat  with  the  method  of  staining  employed.  They  are 
very  thin  and  rounded  at  the  ends.  They  may  be  straight,  but  more  com- 
monly are  shghtly  curved,  and  as  they  often  occur  in  pairs,  the  double  curve 
seen  in  such  a  case  may  suggest  the  notion  of  the  commencement  of  a  spiral ; 
these  appearances,  together  with  their  size,  being  sufficient  to  differentiate 
them  from  other  bacilli  which  most  nearly  resemble  them. 

"When  first  the  tubercle  bacillus  was  discovered,  it  was  thought  the 
invasion  of  the  tissues  by  the  micro-organism  was  the  cause  of  the  develop- 
ment of  phthisis,  but  of  late  the  opinion  has  been  gradually  gaining  ground 
that  the  bacillus,  the  spores  of  which  must  be  abundantly  present  in  the  air 
(and  possibly  in  the  soil},  particularly  in  certainly  localities,  merely  finds  a 
fitting  nidus  in  tissues  of  a  lessened  power  of  resistance,  whether  this  be 
acquired  or  be  due  to  hereditary  taint.  The  multifarious  forms  in  which 
tuberculosis  presents  itself,  both  in  man  and  in  the  lower  animals,  would 
certainly  appear  to  support  this  view,  which,  if  it  be  confirmed  by  subsequent 
observations,  will  necessitate  further  research  in  other  directions  to  eluci- 
date the  true  fetiology  of  the  disease.  Seeing,  however,  that  the  bacilli  may 
almost  invariably  be  found  not  only  in  affected  tissues,  but  also  in  the  sputum 
in  cases  of  tuberculosis  of  the  lungs,  their  detection  will  always  form  a  point 
of  considerable  diagnostic  importance,  so  much  so  indeed,  that  to  use  Koch's 
own  words,  '  A  doctor  who  shall  neglect  to  diagnose  phthisis  in  its  earliest 
stage  by  all  methods  at  his  command,  especially  by  examining  the  sputum, 
will  be  guilty  of  the  most  serious  neglect  of  his  patient.' 

In  the  light  of  our  present  knowledge  of  the  subject,  the  efforts  of 
preventive  medicine  must  be  directed  in  the  first  place  to  the  removal  of 
those  conditions  which  appear  to  bring  about  a  tendency  to  phthisis,  such  as 
dampness  of  soil  and  of  dwellings,  overcrowding,  and  possibly  the  con- 
sumption of  the  milk  of  diseased  cows  and  of  tuberculous  meat. 

At  the  same  time,  contamination  of  the  soil  and  air  by  the  sputum  of 
tuberculous  patients  should  receive  due  attention,  this  bemg  effected  as  far 
as  possible  by  its  reception  on  paper  or  rags,  which  should  be  immediately 
burned,  or  into  spittoons  containing  some  powerful  disinfectant.  The 
removal  of  soil-dampness  is  of  course  only  to  be  carried  out  by  means  of  effi- 
cient drainage  operations,  this  being  a  problem  for  the  engineer  rather  than 
the  medical  officer  of  health. 

The  maps  are  copied  from  those  appended  to  Dr.  Buchanan's  report  on  the  distribu- 
tion of  phthisis  as  affected  by  dampness  of  soil,  contained  in  the  Tenth  Eeport  of  the 
Medical  Officer  of  the  Privy  Council  (1867).     (Plates  IV.  and  V.) 

Plate  IV.  shows  the  broad  geological  features  of  the  district  investigated  ;  the  distribu- 
tion of  the  main  formations,  of  the  broader  tracts  of  alluvium,  and  of  the  more  important 
surface  coverings  of  gravel  and  the  like  being  exhibited  in  a  very  exact  and  reliable  way. 
From  its  scale,  however,  many  points  cannot  be  demonstrated  upon  it,  thus  (1)  narrow 
tracts  of  alluvium  along  streams  are  not  shown ;  (2)  brick-earth  is  not  separated  from 
gravel ;  (3)  the  divisions  of  the  Bagshot  beds  are  not  given — they  are  of  small  moment ; 

(4)  the  divisions  of  the  Lower  Greensand  are  not  shown,  and,  what  is  more  important, 

(5)  the  divisions  of  the  Hastings  beds  into  sands  and  clay  is  not  made ;  these  divisions 
^re  made  in  nature  by  no  long  and  well-defined  boundaries,  but  by  very  irregular  and 
multitudinous  lines  which  could  not  be  exhibited  on  this  small  map ;  (6)  faults  are  not 
marked,  and  (7)  of  the  formations  that  are  shown,  very  small  detached  patches  are,  from 
the  necessity  of  the  case,  omitted. 

Plate  V.  shows  the  registration  districts  of  Kent,  Surrey,  and  Sussex,  numbered  in  the 
order  of  their  phthisis  death-rate,  as  shown  in  the  table  appended,  which  is  copied  from 
Dr.  Buchanan's  report.  Of  these  the  statistics  relating  to  those  numbered  1,  2,  8,  14,  23, 
27,  31  and  41  are  unreliable,  for  various  reasons,  such  as  the  number  of  invalid  visitors 
or  the  migratory  nature  of  the  population. 


3G2 


HYGIENE 


Registration  Districts  in  the  Order  of  their  Proper  Mortality  from  Cojiszcmption, 

{See  Ma2)s) 


1.  Sheppey 

2.  Hastings 

3.  Dartfoid 

4.  Epsom 

5.  Milton 

6.  Godstone 

7.  North  Aylesford 

8.  Thanet 

9.  Dover 

10.  Bromley 

11.  StejTiinR 

12.  Chertsey 

13.  Croydon 

14.  Hoo 

15.  Cranbrook 


16.  Eichmond 

17.  Kingston 

18.  Elham 

19.  Blean 

20.  Bridge 

21.  Gravesend 

22.  East  Grinstead 

23.  Tunbridge 

24.  Eeigate 

25.  Eastbourne 
20.  Farnham 

27.  Med  way 

28.  Hambledon 

29.  Battle 

30.  Canterbury 


31.  Eomney  Marsh 

32.  Hollingbourne 

33.  Mailing 

34.  East  Ashford 

35.  Sevenoaks 

36.  Guildford 

37.  Farnborough 

38.  Eastry 

39.  Faversham 

40.  Eye 

41.  Brighton 

42.  Maidstone 

43.  Cucktield 

44.  Dorking 

45.  Uckfield 


46.  Hailsham 

47.  Ticehurst 

48.  Worthing 

49.  West  Ashford 

50.  Lewes 

51.  Tenterden 

52.  Horsham 

53.  Westhampnett 

54.  Midhurst 

55.  Thakeham 

56.  Petworth 

57.  Westbourne 

58.  Chichester 


DiAEEHCEA 

In  late  summer  and  early  autumn  diarrhoea  is  a  disease  which  is  very  apt 
to  prevail  epidemically,  rural  districts  with  a  scattered  population  being,  how- 
ever, less  alt'ected  than  large  densely  populated  towns.  As  a  fatal  disease  it  is 
conlined  almost  entirely  to  children  under  five  years  of  age,  of  whom  thousands 
are  swept  away  annually  by  what  Fodor  truly  terms  '  the  infants'  destroying 
angel ; '  but  it  is  a  mistake  to  suppose  that  adults  are  not  affected,  since  of 
24,157  attacks  recorded  in  Leicester  during  the  last  four  years  (1885-1889) 
16,506  were  among  persons  over  ten  years  of  age. 

The  subject  was  carefully  investigated  in  1859  by  Dr.  Greenhow,  who 
arrived  at  the  conclusion  that  in  those  places  where  it  prevailed  most 
severely,  a  local  cause  could  usually  be  traced,  consisting  either  of  a  tainting 
of  the  air  with  the  products  of  decomposition  of  organic  matters,  particularly 
of  human  excrement,  or  of  a  contamination  of  the  water-supply.  These  results, 
however,  have  not  been  by  any  means  corroborated  in  subsequent  inquiries  ; 
other  conditions,  such  as  temperature  of  the  air  and  of  the  soil  and  the 
amount  of  rainfall,  having  gradually  come  to  be  considered  of  more  impor- 
tance. Organic  contamination  of  both  soil  and  water  may,  it  has  been  found, 
exist  to  a  considerable  extent  without  the  necessary  supervention  of  summer 
diarrhoea,  provided  that  other  circumstances  are  unfavourable. 

The  seasonal  curve  of  diarrhoea  shows  that  the  mortality  usually  begins 
to  increase  about  the  middle  of  June,  rising  rapidly  to  a  maximum  at  the  end  of 
July  or  beginning  of  August,  and  falling  somewhat  less  rapidly  during  August. 
September,  and  October.  Atmospheric  heat  is  by  no  means  an  essential 
factor  in  the  production  of  this  disease,  however,  since  it  is  never,  even  in  its 
fatal  forms,  really  absent  from  the  population  at  any  period  of  the  year,  being 
met  with  in  winter  as  well  as  summer,  although  not  nearly  to  the  same  extent. 
The  disproportionate  mortality  during  the  summer  is  principally  owing  to  the 
disproportionate  rate  of  attacks  among  a  population,  the  fatality  of  a  given 
number  of  attacks  in  the  one  and  the  other  season  being  not  more  diverse 
than  3  :  1  in  the  summer  as  compared  with  the  winter.  In  the  second  place 
the  epidemic  development  of  the  malady  does  not  always  correspond  with  the 
commencement  of  summer  atmospheric  temperature,  especially  when  the 
latter  is  exceptionally  early.  Moreover,  as  Fodor  has  shown  as  the  result  of 
his  observations  at  Buda-Pesth,  there  may  be  no  apparent  connection  between 
the  air  temperature  and  the  curve  of  diarrhoea,  since,  while  in  the  summer 
of  1863,  which  was  very  warm,  the  number  of  cases  was  small,  in  the  follow- 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  3G3 

ing  year,  which  was  much  cooler,  the  disease  was  very  widespread.  He 
states  also  the  disease  usually  asserts  itself  on  a  sudden,  but  only  after  a 
certain  degree  of  warmth  has  continued  for  a  longer  or  shorter  period,  '  as 
if,'  he  adds,  '  the  virus  in  the  soil  had  first  to  ripen,'  Turner  also,  in  the 
'  Medical  Times  and  Gazette '  for  1879,  endeavoured  to  show  that  a  tempera- 
ture of  over  60°  F.  must  last  at  least  three  weeks  before  diarrhoea  becomes 
excessive.  Again,  the  percentage  of  deaths  from  this  disease  is  not  only 
much  higher  in  towns  than  it  is  in  villages,  but  in  some  cities  and  in  certain 
parts  of  cities  the  disease  is  much  more  prevalent,  although  there  is  no 
difference  of  temperature  to  account  for  it.  Diarrhoeal  epidemicity,  therefore, 
and  the  atmospheric  temperature  by  no  means  invariably  correspond,  although 
not  unfrequently  the  highest  point  of  prevalence  of  the  disease  may  occur  at 
about  the  time  when  the  highest  summer  temperature  is  reached,  or  a  little 
later.  There  is  an  even  more  remarkable  lack  of  correspondence  between 
the  decline  of  the  two  things,  for  although  the  prevalence  of  diarrhoea  lessens 
with  the  falling  temperature  in  October  and  September,  it  does  not  do  so 
proportionately  to  the  fall  in  the  air  temperature,  the  extent  to  which  it  is 
present  among  the  population  being  considerably  greater  than  it  would  be 
with  a  similar  temperature  in  the  earlier  months  of  the  year. 

In  the  same  way  it  is  not  possible  to  trace  any  direct  connection  between 
a  tendency  to  putrefactive  changes  in  articles  of  food  and  drink,  such  as 
might,  in  certain  cases,  be  expected  to  occur  with  a  high  temperature,  and 
the  prevalence  of  diarrhoea.  Milk  particularly  is  very  liable  to  undergo  de- 
composition in  warm  weather,  and  it  has  been  thought  that  its  extensive  use 
as  a  food  for  young  children,  especially  those  only  recently  weaned,  might 
account  in  great  measure  for  the  special  incidence  of  the  disease  during  the 
first  few  years  of  life,  but  this  view  is  obviously  no  longer  tenable,  except  in 
so  far  as  that  such  a  condition  of  things  might  predispose  the  system  to 
suffer  more  severely  when  attacked. 

Dr.  Ballard  has  recently  pointed  out  that  there  is,  on  the  other  hand,  a 
very  considerable  correspondence  between  the  prevalence  of  diarrhoea  epi- 
demics and  the  temperature  of  the  earth  at  a  distance  of  four  feet  from  the 
surface.  In  a  diarrhoea  town,  no  matter  what  the  temperature  of  the  atmo- 
sphere may  have  been  in  the  latter  part  of  the  spring  quarter,  in  May  or 
June,  or  even  in  July,  the  epidemicity  does  not  become  markedly  manifest 
until  the  thermometer,  four  feet  below  the  surface,  shows  a  temperature  of 
about  56°  F.  (13°  C).  He  shows  that  when  this  temperature  is  reached,  and 
so  long  as  it  is  maintained,  the  epidemic  prevalence  continues  there,  and 
commonly  reaches  its  acme  about  the  same  time  as  the  four-feet  earth 
temperature.  An  exception  is  occasionally  seen  to  this,  the  prevalence  of 
the  disease  commencing  to  decline  before  the  four-feet  earth  temperature  has 
reached  its  highest  point.  This  is  noticeable  when  the  earth  temperature 
has  remained  for  some  time  at  about  56°  F.,  such  sustained  high  tempera- 
ture of  the  earth  appearing  capable  of  exhausting  the  potency  for  e'sdl  of  the 
soil  factor  of  the  disease,  whatever  it  may  be,  before  the  extreme  elevation 
has  been  reached.  The  decline  of  an  epidemic  again  shows  little  or  no  rela- 
tion to  that  of  the  air  temperature,  but  often  a  very  close  connection  with 
the  extremely  gradual  and  slower  fall  of  the  four-feet  soil  temperature,  so 
that,  although  the  atmospheric  temperature  may  be  much  lower  in  autumn 
than  in  summer,  the  prevalence  of  diarrhoea  may  be  more  marked.  It 
requires  a  continuance  of  a  fairly  high  air  temperature  for  a  considerable 
period  before  the  soil  temperature,  at  a  depth  of  four  feet,  reaches  56°  F., 
and  until  this  point  is  reached,  the  cause  of  the  disease  appears  to  be  dormant ; 
but  once  that  temperature  in  the  soil  is  touched  in  a  diarrhoea  toTSTi,  an  epi- 


364 


HYGIENE 


demic  arises  more  or  less  explosively,  declining  later  in  a  mucli  more 
leisurely  manner,  so  that  the  different  relation  of  air  temperature  to  the 
prevalence  of  diarrhoea  in  the  spring,  and  in  the  later  months  of  the  year, 
is  still  more  marked  than  if  the  summer  and  autumn  months  be  compared. 

Dr.  Tomldns,  of  Leicester,  who  for  several  years  has  recorded  the  tempera- 
ture of  the  earth  at  one  foot  and  four  feet  levels  during  the  warm  months, 
shows  very  conclusively  that  it  is  not  till  the  temperature  of  the  earth ,  at  a 
depth  of  one  foot,  has  reached  about  00°  F.  (15°-53  C),  and  stands  at  some 
4°  F.  less  than  this  at  four  feet,  that  diarrhoea  begins  to  prevail  to  any  marked 
extent.  He,  however,  regards  the  temperature  at  a  depth  of  one  foot  as  the 
most  significant. 

Reviewing  in  188G-88  statistics  of  diarrhoea  and  infant  mortality  in  the 
city  of  Buffalo,  Snow  found  that  thirty-one  per  cent,  of  the  deaths  under 
one  year  of  age  were  caused  by  acute  intestinal  disease.  He  found  that 
there  w^as  no  constant  relation  betw^een  a  high  average  atmospheric  tempera- 
ture and  the  largest  number  of  fatal  cases,  but  that,  on  the  other  hand, 
greatest  diarrhoea  mortality  occurred  always  in  the  month  in  which  the 
minimum  atmospheric  temperature  attained  its  highest  average  range,  and 
this  altogether  independent  of  the  circumstance  that  such  month  was  not 
necessarily  that  of  maximum  highest  mean  average  temperature.  And  this 
fact  would  appear  not  out  of  harmony  with  the  results  of  Ballard's  researches. 
The  following  table  gi\^ng  the  number  of  deaths  in  Buffalo  for  July  and 
August  for  each  of  three  years,  with  the  mean  average  temperature  and  the 
average  minimum  temperature,  illustrates  the  fact  upon  which  Dr.  Snow 
insists : — 

Table  of  Temperatures  at  Buffalo  for  July  aiid  August  1886,  1887,  and  1888. 


Diarrhoea. 

Jlean  average 

temperature  of 

Average  minimum  night  tem- 

Deaths 

atmosphere  for  each  month 

peratm-e  for  each  month 

1886,  July 

144 

69-4°  F. 

20-77°  C. 

60-3°  F. 

15-72°  C. 

„      August     . 

141 

67-2 

19-55 

60-3 

15-72 

1887,  July 

265 

08-4 

20-22 

67-5 

19-72 

„      August     . 

168 

74-6 

23-66 

64-2 

17-88 

1  1888,  July 

189 

67-4 

19-66 

59-6 

15-33 

j      „      August     . 

212 

67-4 

19-66 

64-0 

17-77 

A  study  of  meteorological  conditions  during  two  of  these  years  seemed  to 
show  that  cholera  infantum  is  much  more  prevalent  in  a  dry  than  in  a  wet 
season,  this  possibly  being  in  turn  due  to  the  fact  that  in  a  dry  season  the 
temperature  of  the  soil  would  be  likely,  other  things  being  equal,  to  reach  a 
higher  point  than  in  the  opposite  case.  This  same  fact  has  been  insisted  on 
by  Fodor,  who  states,  as  the  result  of  his  experience,  that  an  exceptional  rain- 
fall occurring  in  the  midst  of  even  the  most  violent  epidemic  will  be  followed, 
after  from  eight  to  ten  days,  by  a  large  reduction  in  the  death-rate,  but  that  on 
cessation  of  the  rain  the  disease  may  assert  itself  afresh.  The  results  of  Power's 
investigations  at  Leicester  are  also  in  harmony  with  this  statement. 

Lithe  table  compiled  by  Dawson  Williams  (p.  365),  the  two  years  1887  and 
1888  are  chosen  for  comparison,  because  1887  was  exceptionally  warm  and 
dry,  while  1888  was  unusually  cold  and  wet.  The  table  shows  also  that  the 
endemic  prevalence  of  fatal  diarrhoea  in  London  may  occur  with  a  lower  air 
temperature  than  60°  F. 

A  certain  amount  of  moisture  of  the  soil,  however,  is  favourable  to  the 
prevalence  of  diarrhoea,  and  as  warmth  is  also  a  necessary  factor,  it  is  highly 
probable  that  it  is  to  microphytic  processes  going  on  in  the  upper  layers  of 
the  soil  that  the  epidemic  spread  of  the  disease  is  due.  This  would  afford  an 
explanation  of  the  fact  that  summer  diarrhoea  is,  especially,  a  disease  of  cities 


THE  INFLUENCE   OF  SOIL   ON  HEALTH 


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3G6  HYGIENE 

having  a  polluted  soil,  although  the  organic  matter  present  need  not  necessarily 
be  of  a  faecal  or  excremental  nature.  Diarrhceal  mortality  is  apt  to  be  high 
where  dAvelliugs  are  built  upon  made  ground,  upon  the  refuse  of  towns  or  market 
gardens,  or  where  the  soil  is  fouled  by  the  escape  of  sewage  from  imperfect 
drains,  sewers,  or  cesspits,  or  by  soakage  from  midden-heaps.  It  is  therefore 
to  be  found  most  prevalent  in  those  parts  of  towns  where  the  soil  is  most 
polluted,  as  in  Leicester,  which  has  the  unenviable  notoriety  of  the  highest 
diarrheal  mortality  of  any  of  the  large  towns  of  En^dand,  those  parts  in 
which  the  soil  is  '  made  '  accounting  for  the  larger  proportion  of  the  fatal  cases. 

The  association  of  high  diarrhctal  epidemicity  with  certain  geological 
characters  of  the  soil  is  another  important  point  for  the  elucidation  of  wbich 
Ave  are  mainly  indebted  to  the  researches  of  Dr.  Ballard.  The  one  condition 
which  he  finds  gives  an  almost,  if  not  entirely,  absolute  exemption  from  the 
disease,  is  foundation  of  the  dwellings  of  a  locality  on  hard  and  impervious  rock. 
In  such  a  locality,  the  disease  may  indeed  spread  if  introduced  from  without, 
but  with  this  exception,  the  disease  is  so  rare  that  no  serious  or  fatal  case 
may  occur,  as  in  some  parts  of  Devon  and  Cornwall,  during  a  long  series  of 
years.  On  the  other  hand,  the  looser  and  more  pervious  the  soil,  the  more 
distmctly  is  it  found,  other  conditions  being  equal,  to  be  conducive  to  a  pre- 
valence of  diarrhoea  among  those  who  live  in  such  a  district,  sand,  gravel,  and 
marl  being  those  soils  which  are  most  favourable  to  a  high  diarrhceal  mortahty ; 
while  in  the  case  of  gravel,  the  smaller  its  particles — the  nearer  it  approaches 
to  sand  in  fineness,  or  conversely  the  more  its  stony  element  predominates — 
the  greater  its  likeness  to  rock  in  coarseness,  the  more  or  less  obvious  will 
its  relation  to  the  prevalance  of  diarrhoea  appear. 

Stagnation  of  air,  whether  induced  by  geographical  situation,  to  the 
arrangement  of  streets,  or  to  the  construction  of  houses,  as  when  crowded 
together  on  a  small  area,  or  built  back  to  back  so  as  to  hinder  or  altogether 
prevent  efficient  ventilation,  has  an  important  influence  on  the  progress  of 
the  malady  during  a  period  of  epidemic  prevalence,  acting  in  all  probability 
through  the  retention  in  such  locality  of  the  organisms  given  off  by  the  soil 
under  circumstances  which  have  been  previously  mentioned.  High  winds, 
on  the  contrary,  by  ventilating  the  soil  and  removing  the  strata  of  stagnant 
air  immediately  above  it,  will  check  the  disease  while  they  continue,  and  in 
locahties  where  free  circulation  of  air  is  permitted  and  where  dwelhngs  are 
well  ventilated,  an  epidemic  never  gains  so  firm  a  footing  ;  the  explanation  of 
this  fact  being  that  such  conditions  are  in  the  one  case  favourable  and  in  the 
other  unfavourable  to  the  dissemination  of  the  soil  products  which,  as  far  as 
our  present  knowledge  leads  us,  must  be  considered  the  essential  cause  of  the 
disease. 

Dr.  Klein,  in  the  course  of  an  extensive  microscopical  investigation,  has 
failed  to  find  anything  in  the  tissues,  blood,  or  excreta  of  a  number  of  diarrhoea 
cases  to  indicate  that  any  definite  microbe  is  concerned  in  the  production  of  the 
disease  ;  but  Dr.  Ballard,  arguing  from  the  fact  that  in  certain  groups  of  cases 
in  which  it  is  apparently  communicated  from  person  to  person  by  means  of 
the  exhalations  from  the  stools,  believes  that  in  the  excretions  of  such  cases  a 
specific  micro-organism  will  yet  be  found.  The  conclusions  at  which  he  has 
arrived  as  the  result  of  his  researches  may  best  be  given  in  his  OAvn  words  : — 

'  That  the  essential  cause  of  diarrhoea  resides  ordinarily  in  the  superficial 
layers  of  the  earth,  where  it  is  intimately  associated  with  the  life  processes 
of  some  micro-organism,  not  yet  detected,  captui'ed,  or  isolated. 

'  That  the  vital  manifestations  of  such  organism  are  dependent,  among 
other  things,  perhaps  principally,  upon  conditions  of  season,  and  on  the 
presence  of  dead  organic  matter,  which  is  its  pabulum. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  307 

'That,  on  occasion,  such  micro-organism  is  capable  of  getting  abroad 
from  its  primary  habitat,  the  earth,  and  having  become  air-borne,  obtains 
opportunity  for  fastening  on  non-hving  organic  material,  and  of  using  such 
organic  material  both  as  nidus  and  pabulum  in  undergoing  various  phases  of 
its  life-history. 

'  That  in  food,  inside  of,  as  well  as  outside  of  the  human  body,  such 
micro-organism  finds,  especially  at  certain  seasons,  nidus  and  pabulum  con- 
venient for  its  development,  multiplication,  or  evolution. 

'  That  from  food,  as  also  from  the  contained  organic  matter  of  parti- 
cular soils,  such  micro-organisms  can  manufacture  by  the  chemical  changes 
wrought  therein,  through  certain  of  their  life-processes,  a  substance  which  is 
a  virulent  chemical  poison  (probably  ptomaine). 

'  That  this  chemical  substance  is,  in  the  human  body,  the  material  cause 
of  epidemic  diarrhoea.' 

In  connection  with  the  fact  that  rising  currents  of  ground-air  may  carry 
bacteria  out  of  the  soil  into  the  atmosphere  above,  it  is  worthy  of  note,  per- 
haps, that  observations  have  been  recorded  by  Dr.  Tomldns  on  bacteria  in  the 
air  in  diarrhoeal  districts  in  Leicester.  His  experiments  were  directed  to 
ascertain  the  relative  number  of  germs  present  in  the  atmosphere  in  different 
parts  of  the  town,  and  particularly  in  those  portions  most  affected,  both  be- 
fore and  during  an  epidemic.  While  diarrhoea  was  prevalent  he  found  from 
two  to  three  times  as  many  microbes  in  the  air  as  before  or  after  this  period, 
while  in  the  particular  region  specially  affected  there  were  fourfold  as  many 
as  in  other  districts  where  the  disease  did  not  prevail.  None  of  the  bac- 
teria, however,  have  been  isolated  or  worked  out,  and  the  mere  presence 
of  germs  in  quantity  is  no  positive  proof  of  their  causative  agency,  so  that 
these  experiments  cannot  be  regarded  as  creating  anything  more  than  a  pre- 
sumption in  favour  of  the  influence  of  pathogenic  organisms  in  this  disease, 
more  particularly  as  no  simultaneous  bacteriological  examination  of  the  soil 
was  carried  out. 

Dysenteey 

Many  writers  have  considered  that  both  dysentery  and  malaria  are  due 
to  a  similar  cause,  for  the  reason  that  these  diseases  appear  equally  to  prevail 
in  almost  all  situations,  such  as  the  vicinity  of  the  swamps  and  sluggish 
rivers  of  tropical  and  sub-tropical  countries,  which  are  the  breeding-ground 
of  intermittent  fevers. 

The  two  diseases  indeed  may  occur  together  in  the  same  patient  and  at 
the  same  time,  and  Dr.  Aitken  has  stated  that  if  a  boat's  crew  be  sent  ashore 
in  a  tropical  climate,  and  exposed  to  paludal  miasmata,  the  probabilities  are 
that  of  the  men  returning  on  board  some  will  be  seized  with  dysentery  and 
some  with  intermittent  fever.  It  is  also  a  well-established  fact  that  where, 
both  in  Great  Britain  and  other  countries,  the  tendency  to  attacks  of  malaria 
has  been  diminished  by  improved  drainage,  and  the  conversion  of  marshes 
into  cultivated  land,  there  also  dysentery  has  gradually  diminished  to  an 
equal  extent.  There  are,  however,  places  in  which  dysentery  occurs  even  in 
an  epidemic  form,  but  which  never  under  any  circumstances  yield  ague, 
while  also  all  aguish  districts  are  not  necessarily  dysenteric.  Moreover, 
the  two  diseases  never  graduate  the  one  into  the  other,  so  that  although  it 
is  possible  that  the  real  cause  of  dysentery  is  some  poison  alhed  to  that 
which  produces  malaria,  the  two  need  not  be  identical. 

Dysentery,  although  still  common  in  some  parts  of  the  world,  has  not 
occurred  epidemically  in  London  since  1762,  but  isolated  cases  are  still  to  be 
met  with  which  have  been  imported  into  this  country  from  districts  on  the 


368  EYGIEXE 

Mediterranean  coast  line,  from  India,  Africa,  Central  America,  and  elsewhere. 
Until  within  recent  years,  however,  small  outbreaks  of  the  disease  were  of 
constant  occurrence  in  Millbank  Prison.  These  were  investigated  by  Dr. 
Baly,  and  subsequently  by  Dr.  Maclean,  both  of  whom  believed  them  to  be 
related  to  emanations  from  the  soil  on  which  the  prison  stands,  consequent 
on  the  decomposition  of  organic  matter.  It  is  more  probable,  however,  that 
the  water  supply  rather  than  the  ground  air  was  at  fault,  since  when  in  1854 
the  direct  supply  of  water  fi'om  the  river  Thames  was  exchanged  for  that 
obtained  from  the  artesian  well  in  Trafalgar  8quare,  dysentery  suddenly 
declined,  and  from  that  time  has  been  unknowTi. 

That  soil  laden  with  products  of  decomposing  sewage  and  the  like  may, 
however,  be  an  important  factor  in  the  genesis  of  the  disease  is  amply  proved 
by  an  interesting  account  given  by  Fagge  of  a  series  of  epidemics  which 
occurred  in  the  Cumberland  and  Westmorland  Asylum  during  the  years 
1804,  18G5,  and  1808.  For  a  long  time  no  cause  for  the  production  of  the 
disease  could  be  traced,  although  it  had  been  thought  possible  that  it  might 
be  connected  with  the  fact  that  the  sewage  of  the  asylum,  after  being  thrown 
into  a  large  tank,  was  distributed  over  a  field  about  three  hundred  yards 
distant.  On  hot  and  sultry  evenings  an  offensive  smell  was  often  noticed, 
and  Dr.  Clouston,  the  medical  superintendent,  then  had  the  sewage  carried 
away  to  a  distance  tlu'ough  a  covered  drain,  with  the  result  that  no  fresh 
cases  of  dysentery  occurred.  An  investigation  was  then  made  as  to  the  exact 
meteorological  conditions  which  had  existed  during  the  prevalence  of  the 
epidemic,  and  it  was  found  that  within  a  week  before  the  day  on  which  each 
patient  fell  ill  there  had  always  been  either  hot  sultry  evenings,  with  no  wind 
in  the  night,  or  northerly  winds  which  blew  from  the  direction  of  the  field 
which  was  being  irrigated.  Male  and  female  patients,  too,  were  attacked  at 
different  times,  according  as  the  exact  direction  of  the  wind  was  such  as  to 
carry  the  sewage  emanations  either  to  one  or  the  other  of  the  parts  of  the 
building  which  the  two  sexes  severally  occupied. 

In  the  following  year  five  cases  of  dysentery  all  occurred  within  a  week 
after  the  sewage  had  again  been  allowed  to  flow  over  the  field  during  a  calm 
night,  when  the  direction  of  the  wind  happened  to  be  towards  the  asylum. 
From  this  time  the  disease  entirely  disappeared  for  more  than  two  years,  but 
on  another  attempt  being  made  to  get  rid  of  the  sewage  by  irrigation,  although 
special  precautions  were  taken,  and  another  field  chosen,  six  patients  con- 
tracted dysentery  within  a  couple  of  months  of  the  commencement  of  the 
experiment.  All  the  cases  occurred  in  that  part  of  the  asylum  nearest  the 
field,  and  towards  which  the  wind  had  been  blowing  continuously  for  eight 
days  before  the  outbreak  occurred.  The  subsoil  of  the  land  surrounding  the 
asylum  was  a  stiff'  clay  which  was  impermeable  to  water,  and  which  con- 
sequently was  quite  unfit  for  irrigation  purposes,  the  sewage  simply  stagnating 
thereon  for  an  indefinite  length  of  time. 

Season  has  apparently  some  influence  on  the  prevalence  of  dysentery,  as 
both  in  tropical  and  temperate  chmates  it  is  more  apt  to  appear  in  autumn 
than  at  other  times  of  the  year.  The  temperature  of  the  atmosphere,  or  per- 
haps of  the  soil,  is  also  a  factor  which  must  be  taken  into  consideration,  as  it 
has  not  unfrequently  been  observed  that  the  disease  has  occurred  to  a  greater 
extent  in  years  which  were  exceptionally  hot. 

Whether  any  micro-organism  be  concerned  in  the  production  of  dysentery 
is  not  at  present  known ;  but  some  observers  maintain  that  it  is  certainly 
contagious.  The  researches  of  Hornan  and  Hertwig  in  Norway  would  seem 
to  prove  that  the  disease  may  be  conveyed  by  healthy  persons  from  infected 
places  to  other  spots  where  the  disease  had  not  before  appeared,  and,  arguing- 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  369 

from  the  analogy  of  cholera  and  enteric  fever,  it  appears  quite  possible  that 
there  may  be  present  some  organism  which  is  capable  of  multiplication  in 
the  body,  and  which  reaches  the  outer  world  in  the  alvine  evacuations. 

Lead-Poisoning 

This  disease,  or  rather  a  form  of  it  which  has  been  very  prevalent  of  late 
years  in  some  parts  of  England,  must,  in  the  light  of  recent  researches,  be 
included  in  the  list  of  those  which  are  predisposed  to  by  certain  conditions  of 
the  soil,  although  at  first  sight  the  relation  may  not  appear  obvious.  In 
Yorkshire  particularly,  lead-poisoning  has  always  been  more  or  less  prevalent 
owing  to  the  trades  carried  on  there,  the  file-cutters  being  specially  liable 
to  suffer  from  this  disease,  but  after  eliminating  all  cases  of  lead-poisoning 
arising  from  trade,  a  large  number  still  remain  for  which  the  only  cause 
appears  to  be  the  taking  of  lead  into  the  system  through  the  medium  of  the 
drinking  water  ;  this  supposition  being  confirmed  by  chemical  examination  of 
the  water  which  has  been  found  to  contain  varying  but  often  large  quanti- 
ties of  lead. 

The  poisonous  nature  of  the  water  in  the  affected  areas  is  due  to  its 
capacity  for  taking  up  lead  from  the  pipes  by  means  of  which  the  water  is 
distributed.  Such  water  is  obtained  from  high  gathering  grounds  on  the 
moors,  and  is  very  soft  and  otherwise  of  excellent  quality,  and  although  the 
amount  of  albuminoid  ammonia  is  usually  somewhat  high,  in  the  absence  of 
chlorides  and  nitrates  this  must  obviously  be  of  vegetable  origin,  the  peat 
which  is  so  plentiful  at  the  gathering  grounds  occasionally  also  giving  the 
water  a  brownish  tint.  Where  a  town  or  district  has  a  low-level  supply  also, 
it  is  found  that  this  has  no  such  solvent  action  on  lead  ;  the  only  reason  for 
this  difference  being  found  apparently  in  an  acid  reaction  of  the  high-level 
water,  that  obtained  from  the  low-level  gathering  grounds,  on  the  other  hand, 
being  neutral  or  faintly  alkaline. 

As  to  the  nature  of  the  acid  which  is  present  there  is  considerable  diver- 
gence of  opinion,  since  its  small  amount  makes  an  accurate  determination, 
a  matter  of  great  difficulty.  It  appears,  moreover,  that  the  acid  which  is 
found  in  the  water  obtained  from  the  service  pipes  is  not  in  some  cases  the 
same  as  that  to  which  the  acid  reaction  of  the  water  at  the  gathering  grounds 
is  due,  some  chemical  decomposition  apparently  taking  place  during  its  pas- 
sage through  the  reservoirs  and  mains.  The  amount  present,  therefore,  is 
generally  expressed  in  terms  of  sulphuric  acid,  which  by  some  observers  is 
believed  to  be  that  which  is  always  present  in  the  water.  It  has  been 
suggested  that  such  free  sulphuric  acid  might  be  derived  from  the  oxidation 
of  iron  pyrites  in  the  shale  which  usually  underhes  the  beds  of  peat ;  but  even 
though  it  may  be  present  in  the  water  of  the  moorlands,  it  by  no  means 
follows  that  the  acid  will  be  the  same  when  the  water  reaches  the  lead  service 
pipes,  since,  meeting  with  salts,  it  may  have  decomposed  these  with  the 
formation  of  sulphates,  other  acids  being  set  free. 

That  this  is  often  so  can  be  shown  by  neutrahsing  the  water,  evaporating 
to  dryness,  and  igniting  the  residue,  when  a  carbonate  is  formed,  thus  proving 
that  the  acid  now  present  is  of  an  organic  nature.  It  is  also  non-volatile, 
since  usually  none  appears  to  be  lost  on  concentration  of  the  water.  An 
obvious  source  from  which  such  acid  might  be  derived,  is  the  peat  of  the 
moors,  since  it  has  been  known  for  some  time  that  the  decomposition  of  peat 
and  other  vegetable  substances  gives  rise  to  the  formation  of  several  bodies 
which  have  been  described  under  the  names  of  crenic,  apocrenic,  ulmic, 
and  humic  acids.     Unfortunately,  however,  the  hterature  of  the  subject  is 

VOL.  I.  B  B 


370  HYGIENE 

extremely  scanty,  and  there  is  considerable  doubt  wlietber  any  of  tliese  acids 
have  ever  been  prepared  in  an  absolutely  pure  state.  In  support  of  the 
opinion  that  it  is  to  the  presence  of  one  or  more  of  these  bodies  that  the 
reaction  of  the  water  is  due,  it  may  be  mentioned  that  where  the  peat  is  most 
abundant  the  acid  reaction  and  the  amount  of  organic  matter  evidently  of 
vegetable  origin  are  most  noticeable. 

As  suggested  by  Mr.  Power  in  his  memorandum  on  lead-poisoning  from 
certain  public  water-supplies,  contained  in  the  Report  of  the  IMedical  Officer 
to  the  Local  Government  Board  for  1887,  it  is  possible,  however,  that  yet 
another  factor  has  to  be  considered.  He  believes  that  the  action  of  the  water 
on  lead  might  be  due  to  the  growth  of  micro-organisms  in  the  water,  basing 
this  opinion  on  the  facts :  (1)  that  the  action  on  lead  presents  marked 
seasonal  variations,  being  most  intense  in  the  autumn,  particularly  in 
September,  October,  and  November ;  (2)  that  instances  are  found  where  the 
ability  to  act  on  lead  has  been  newly  acquired  by  a  water-supply,  so  suddenly 
and  in  such  a  manner  that  a  great  quantity  of  lead-poisoning  is  produced, 
without  any  known  change  in  the  sources  of  water-supply,  among  the 
inhabitants  of  a  town  that  had  previously  been  unacquainted  with  the  disease; 
and  (3)  finally  that  the  introduction  of  some  comparatively  small  portion  of 
a  plumbo-solvent  water  into  the  total  water-supply  of  a  town  has  appeared 
to  confer  upon  the  whole  of  such  supply  the  power  of  dissolving  lead  from 
the  domestic  service  pipes  of  the  town. 

The  growth  of  bacteria  is  naturally  favoured  by  warmth,  so  that  the 
fermentation  processes  would  be  most  active  in  the  hottest  part  of  the  year, 
when  also  a  somewhat  lessened  rainfall  and  greater  evaporation  would  tend 
to  the  relative  as  well  as  absolute  increase  in  the  amount  of  the  products 
of  the  life-processes  of  the  micro-organisms  in  the  water,  and,  as  has  been 
stated,  it  is  apparently  in  the  few  months  immediately  following  the  latter 
part  of  the  summer  that  the  effects  of  the  increased  action  of  the  water  on 
lead  are  most  prone  to  manifest  themselves. 

If  this  be  so,  it  does  not  necessarily  disprove  the  truth  of  the  acid  theory, 
as  it  is  quite  possible  that  the  organic  substances  which  yield  the  acid 
detected  in  the  water  may,  at  any  rate  in  part,  be  the  result  of  the  presence 
of  bacteria,  while  some  may,  on  the  other  hand,  be  directly  derived  from  the 
peaty  soil.  It  is  hardly  necessary  to  add  that  the  presence  of  so  large  an 
amount  of  organic  matter  in  the  water,  as  is  shown  by  analysis,  would  form 
a  most  favourable  pabulum  for  the  development  of  micro-organisms,  especially 
when  exposed  to  light  and  air  in  the  uncovered  reservoirs.  In  this  connec- 
tion it  is  worthy  of  note  that  in  a  number  of  places  visited  for  the  purpose 
of  investigating  this  subject,  the  sudden  increase  in  the  amount  of  lead- 
poisoning,  which  first  appeared  in  1888,  followed  the  dry  year  1887,  when  in 
Sheffield,  for  instance,  the  rainfall  for  the  twelve  months  was  the  lowest  that 
had  been  recorded  for  fifty  years.  The  result  of  this  drought  was  that  when 
afterwards  rain  first  fell  in  any  quantity  a  considerable  amount  of  storm- 
water  which  would  usually  have  Ijeen  diverted  into  other  channels  was  allowed 
to  pass  mto  the  reservoirs,  into  which  it  would  be  likely  to  carry  countless 
numbers  of  bacteria  and  their  spores,  which  would  usually  be  more  or  less 
perfectly  removed  by  filtration  through  the  soil,  and  these  would  rapidly 
multiply  in  the  comparatively  stagnant  water. 

Dr.  W.  E.  Smith  has  conducted  a  series  of  biological  experiments  on 
behalf  of  the  Local  Government  Board  for  the  purpose  of  determining,  if 
possible,  whether  in  waters  which  have  been  proved  to  possess  considerable 
plumbo-solvent  power,  microphytes  are  to  be  found  which  are  capable  of 
working,  by  their  life  processes,  acid  changes  in  artificial  culture  media.     So 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  371 

far  as  these  experiments  have  gone,  although  they  are  not  yet  numerous, 
nor,  according  to  Dr.  Buchanan,  at  all  conclusive,  their  results  appear  to  be 
affirmative,  since  the  growth  of  some  micro-organisms  obtained  from  waters 
of  this  class  is  accompanied  by  a  distinctly  acid  reaction  in  the  media  in 
which  they  have  been  grown.  Further  observations  are,  however,  needed 
before  the  matter  can  be  considered  to  have  been  placed  on  a  sufficiently 
satisfactory  basis  to  give  definite  indications  as  to  the  treatment  necessary 
for  obviating  a  source  of  grave  danger  to  a  considerable  section  of  the  com- 
munity, and  Dr.  Buchanan  has  pointed  out  that  such  researches  should  be 
primarily  pursued  by  local  investigations  into  the  environments  of  the  various 
water  sources,  and  into  the  conditions  affecting  the  distribution  of  such  water, 
observing  always  the  conditions  of  time  and  place  surrounding  the  waters 
that  have  the  power  of  acting  on  lead,  and  comparing  them  with  the  con- 
ditions that  environ  the  waters  which  do  not  show  that  power.  Meanwhile, 
seeing  that  it  is  apparently  to  the  presence  of  free  acid  of  some  kind  or  other 
that  the  action  of  these  plumbo- solvent  waters  is  due,  the  logical  proceeding 
is  obviously  to  neutralise  the  acid,  either  with  carbonate  of  sodium,  with  lime, 
or  with  carbonate  of  calcium  in  the  form  of  chalk  or  limestone.  That  such 
treatment,  when  properly  applied,  is  an  efficient  agent  in  preventing  the 
solvent  action  of  water  on  lead  has  been  proved  in  Dessau,  which  is,  Hke 
many  of  the  towns  of  Yorkshire  and  Derbyshire,  supplied  with  soft  water. 
This  water,  which  showed  an  acid  reaction  to  which  its  lead-dissolving  power 
appeared  to  be  due,  has  become  quite  inoperative  in  this  respect  since  a 
method  of  neutralising  the  acid  has  been  successfully  carried  out,  and  it 
would  appear  that  a  similar  line  of  treatment  has  been  equally  efficacious  in 
certain  districts  in  this  country.     (See  also  Water,  ante,  p.  256). 

Tetanus 

It  is  usual  to  recognise  a  traumatic  and  an  idiopathic  form  of  this  disease, 
but  the  results  of  modern  research  all  tend  to  support  the  view  advanced  by 
Verneuil  that  tetanus  is  never  of  spontaneous  origin,  but  always  arises  from 
traumatic  infection.  The  active  agent  in  the  causation  of  the  disease  would 
seem  to  be  a  micro-parasite  first  discovered  by  Nieolaier  in  garden-earth  and 
subsequently  by  Eosenbach  in  human  beings  suffering  from  tetanus.  Nieolaier, 
experimenting  on  mice,  guinea-pigs,  and  rabbits,  found  that  when  soil  from 
fields,  gardens,  or  roads  was  introduced  subcutaneouslyin  these  animals,  clonic 
spasms  of  the  parts  nearest  the  point  of  inoculation  were  produced,  and  that 
this  was  followed  in  about  twenty-four  hours  by  general  tetanus.  Eosenbach 
induced  similar  effects  in  guinea-pigs  and  rabbits  by  implanting  beneath  the 
skin  small  pieces  of  tissue  obtained  from  the  neighbourhood  of  the  wounded 
part  in  a  man  dying  of  tetanus.  The  disease  was  not  only  produced  in  the 
animals  first  experimented  on,  but  by  inoculation  of  material  from  the  neigh- 
bourhood of  the  wound  from  case  to  case  it  was  propagated  through  a  long 
series  of  other  animals.  In  each  case  the  bacillus  could  be  found  in  the  tissues 
near  the  point  of  inoculation,  but  not  in  the  blood  or  any  of  the  internal 
organs.  It  is  an  interesting  point  that  in  cases  of  tetanus  in  the  human 
being  also,  the  bacillus  has  never  been  demonstrated  in  the  blood,  or  tissues 
other  than  those  at  the  site  of  the  lesion ;  and,  moreover,  inoculations  with 
tetanic  blood  alone  have  never  given  anything  but  negative  results,  while  when 
pus  or  lymph  from  the  neighbourhood  of  the  wound  was  used,  positive  results 
have  for  the  most  part  been  obtamed.  It  would  appear,  therefore,  that  the 
bacillus  produces  a  ptomaine  which,  when  absorbed  into  the  blood,  gives  rise 
to  the  characteristic  symptoms  of  the  disease.  This  idea  is,  of  course,  strongly 
supported  by  the  fact  that  the  bacillus  is  only  found  ia  the  neighbourhood 

BB  2 


372  HYGIENE 

of  the  wound,  and  Brieger  states  that  he  has  separated  from  an  impure' 
culture  of  the  baciUus  a  body  to  which  he  has  given  the  name  of  tetaniney 
because  it  produced  tetanus  in  animals  even  when  injected  in  minute  quantity, 
by  virtue  of  its  extremely  poisonous  eflect  on  the  nerve-centres.  He  suc- 
ceeded, moreover,  in  obtaining  a  similar  ptomaine  from  the  amputated  arm 
of  a  tetanic  patient,  and  he  believes  that  his  experiments  prove  that  the 
disease  is  due  to  a  species  of  septic  intoxication. 

The  question  of  the  identity  of  traumatic  and  so-called  spontaneous  tetanus 
is  a  most  interesting  one,  and  would  seem  to  be  strongly  supported  by  ex- 
periments carried  out  by  Lampiasi,  who,  starting  from  a  case  of  spontaneous 
tetanus,  obtained  a  virus,  which  after  the  lapse  of  two  years  was  still  capable 
of  inducing  tetanus  in  a  virulent  form.  Earth  also  is  capable  of  retaining  its 
infective  property  unimpaired  for  a  considerable  length  of  time,  specimens 
which  had  been  kept  in  a  laboratory  for  between  three  and  four  years  having 
caused  t}^ical  tetanic  attacks  when  inoculated  into  animals.  This  point  is 
demonstrated  by  Dr.  Peyraud  in  an  account  of  some  experiments  carried  out 
with  soil  taken  from  a  covered-in  enclosure  in  which  wine  was  stored,  and  which 
had  not  in  any  way  been  cultivated  since  the  store  was  erected.  With  this 
soil  he  obtained  positive  results  in  all  his  experiments,  and  five  out  of  every 
six  of  the  animals  inoculated  died. 

Kitasato  was  the  first  to  obtain  pure  cultures  of  the  bacillus  of  tetanus. 
A  patient  having  succumbed  to  the  disease,  he  first  inoculated  pus  from  the 
wound  into  rabbits,  and  having  obtained  positive  results,  he  proceeded  as 
follows  : — Some  of  the  pus  was  inoculated  into  solidified  blood  serum  and 
agar-agar,  to  which  had  been  added  two  per  cent,  of  grape-sugar.  These 
cultures  were  kept  at  a  temperature  of  37°  C.  for  twenty-four  hours,  when  they 
were  found  to  contain  a  number  of  micro-organisms,  including  the  bacillus  of 
tetanus,  in  small  numbers,  while  on  the  following  day  the  number  had  in- 
creased considerably.  The  tubes  were  then  exposed  to  a  temperature  ot 
80°  C.  for  about  an  hour  in  a  water-bath  in  order  to  kill  any  other  microbes 
present,  and  the  contents  inoculated  into  mice  in  which  characteristic  tetanus 
was  induced.  The  spores  remaining  in  the  tubes  were  cultivated  on  plates, 
and  also  in  closed  vessels  containing  hydrogen,  which  were  kept  at  a  tempe- 
rature of  20°  C.  A  week  later  the  plates  were  sterile,  while  colonies  were 
visible  in  the  hydrogen  tubes,  showing  that  the  bacillus  is  ana3robic. 

The  cultivations  have  a  repulsive  and  penetrating  odour,  due  to  gas  which 
is  evolved  during  growth.  They  retain  their  virulence  through  successive 
generations,  especially  when  mixed  with  sterilised  earth. 

The  spores  of  the  bacillus  are  very  tenacious  of  life,  although  active  growth 
is  suspended  below  a  temperature  of  18°  C. ;  they  are  able  to  withstand  a 
temperature  of  80°  C.  for  from  half  an  hour  to  an  hour,  but  a  moist  heat  of 
100°  C.  destroys  them  in  about  five  minutes.  Ten  hours'  immersion  in  a  five 
per  cent,  solution  of  carbolic  acid  does  not  impair  their  virulence,  but  they 
are  killed  in  fifteen  hours  ;  a  solution  of  corrosive  sublimate  (1  in  1,000)  kills 
them  in  about  thirty  minutes,  particularly  if  it  be  acidified. 

The  bacillus  has  the  form  of  a  slender  rod,  which,  when  actively  growing 
usually  presents  a  swollen  and  bulged  extremity,  due  to  the  presence  of  a  large 
terminal  spore.  The  bacillus,  which  is  motile,  seems  occasionally  to  multiply 
by  fission,  formmg  short  chains.  Staining  reagents  for  the  most  part  stain 
the  rods,  but  leave  the  spores  untouched. 

When  inoculated  into  solid  nutrient  media,  growth  commences  below  the 
surface,  and  as  it  increases  and  the  bacilli  gradually  penetrate  the  mass  of 
nutrient  material,  a  fine  feathery  appearance  is  produced  which  is  quite 
typical. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  373 

The  telluric  origin  of  tetanus  has  recently  been  investigated  by  Bassano 
in  a  series  of  experiments  carried  on  at  Marseilles.  Six  specimens  of  earth 
were  obtained  from  dry  localities  which  had  not  been  contaminated  with 
putrefactive  or  organic  material  for  a  long  time,  and  used  for  the  inoculation 
of  twelve  cobayes,  but  no  results  followed.  Ten  specimens  of  earth  were 
then  taken  from  cultivated  land,  meadows,  or  roads,  and,  each  being  inocu- 
lated upon  two  animals  gave  positive  results.  The  inoculations  were  in  each 
case  made  in  the  right  flank  at  the  level  of  the  hind  limb.  Four  of  the 
animals  died  of  septicaemia ;  the  other  sixteen  all  presented  similar  morbid 
phenomena  as  follows  : — Eigidity  of  the  limb  adjacent  to  the  seat  of  inocula- 
tion was  observed  two  days  after  the  inoculation,  the  limb  becoming  forcibly 
extended  as  this  rigidity  increased.  By  the  third  day  the  opposite  limb  was 
likewise  extended,  and  the  animal  assumed  and  preserved  the  dorsal  decubi- 
iiTS ;  then  appeared  trismus,  and  in  the  majority  of  cases  extreme  dyspnoea, 
which  increased  until  death  closed  the  scene,  the  fatal  termination  being 
not  unfrequently  preceded  by  violent  convulsions.  This  gradual  implication 
of  successive  parts  of  the  body  following  on  symptoms  commencing  in  the 
neighbourhood  of  the  inoculated  spot  is  very  typical,  and  throws  light  upon 
the  action  of  the  bacilli.  As  evidence  that  the  resulting  tetanus  is  really 
due  to  inoculation  of  a  specimen  of  earth  or  a  culture  of  the  organism  at 
the  particular  spot,  the  experience  of  other  observers  also  is  of  considerable 
interest.  Thus  Lockwood  states  that  a  few  hours  (usually  less  than  twenty- 
four)  after  the  root  of  a  mouse's  tail  has  been  inoculated  with  an  appreciable 
quantity  of  pure  culture,  the  tail  becomes  rigid,  and  either  bent  to  one  side  or 
in  a  corkscrew  fashion ;  the  hind  legs  are  next  seized  with  spasms,  and  some- 
times with  tremors.  The  spasm  becomes  so  intense  that  first  one  and  then 
the  other  leg  is  extended,  with  the  sole  of  the  foot  turned  upwards  ;  then  the 
muscles  of  the  trunk,  of  the  fore-limbs,  and  of  the  neck  and  head  become 
tetanic  in  definite  order,  those  nearest  the  point  of  inoculation  first,  and 
afterwards  those  at  a  distance  ;  and  in  about  twenty-four  hours  the  animal 
is  dead.  If  the  neck  or  fore-limbs  be  inoculated,  instead  of  the  root  of  the 
tail,  the  tetanus  begins  in  them.  The  period  of  inoculation  varies,  being 
about  twenty-four  hours  in  the  mouse,  five  days  in  rabbits,  and  from  about 
four  to  sixteen  days  in  the  human  subject. 

Verneuil  has  expressed  the  opinion,  to  which  he  still  firmly  adheres,  that 
"tetanus  is  of  equine  origin.  He  accepts  as  proven  that  the  disease  is  a  pro- 
duct of  a  special  micro-organism,  and  formulates,  among  others,  the  following 
conclusions  :  '  It  is  probable  that  several  domestic  animals  are  able  to  infect 
man,  but  satisfactory  demonstration  has  been  hitherto  given  only  for  soli- 
peds.  A  wounded  man  can  contract  tetanus  from  the  majority  of  neigh- 
bouring objects  which  may  touch  his  wound,  but  observation  and  experience 
show  that  far  the  most  dangerous  objects  are  the  horse  with  his  immediate 
surroundings,  then  cultivated  earth  and  some  of  its  products  ;  hence  arises 
conflict  between  the  equinist  and  the  tellurist.  Accord  would  be  easy  if,  in 
accepting  the  deductions,  one  would  subordinate  the  one  to  the  other,  and 
recognise  that  if  earth  is  able  to  induce  tetanus  it  does  so  because  it  is  soiled 
by  the  tetanised  horse.'  He  further  argues  that  the  disease  is  never  spon- 
taneous, but  is  always  due  to  infection.  His  views  have  received  great 
support  in  France,  so  much  so  that  we  find  cases  recorded  because  no  contact 
with  horses  could  be  discovered.  Other  observers  admit  the  power  of  culti- 
vated soil  to  give  rise  to  tetanus,  but  do  not  believe  that  this  is  due  to  horse- 
manure  rather  than  to  that  of  any  other  animal,  as  the  ox  or  sheep,  and 
they  strongly  oppose  the  equine  origin  of  tetanus,  not  because  such  may  not 
be  its  origin,  but  because  they  consider  that  this  has  not  yet  been  proved  to 
be  the  case. 


374  HYGIENE 

The  microbe  of  tetanus,  like  the  vibrio  of  gangrenous  septicaemia,  may 
be  innocuous  in,  and  pass  unchanged  through,  the  ahmentary  canal  of  an 
herbivorous  animal,  and  Sarmani,  in  Italy,  has  apparently  discovered  that 
such  may  be  the  case,  not  only  in  herbivorous  but  also  in  carnivorous 
animals,  the  micro-organism  stiU  keeping  its  infective  power.  Hence 
manure  may  become  a  potent  source  of  tetanus  dissemination.  On  the 
other  hand,  horses  are  imknown  in  the  New  Hebrides,  yet  tetanus  is  very 
common,  but  this,  of  course,  is  only  negative  e\idence.  In  the  case  of  two 
patients  mentioned  by  Eichelot  afi'ected  with  tetanus  after  ovariotomy,  the 
disease  appeared  shortly  after  manure  had  been  spread  in  the  hospital  court, 
thus  suggesting  also  that  air  may  be  a  vehicle  for  the  transfer  of  virulent 
germs.  Terillon  also  reports  a  case  in  which  tetanus  developed  fi'om  a 
wound  caused  by  a  horse-shoe  soiled  with  manure. 

There  cannot  now  be  any  reasonable  doubt  that  the  tetanus-producing 
bacillus  is  very  widely  distributed  in  the  superficial  layers  of  various  kinds 
of  soil,  on  the  foul  surface  of  streets,  and  in  the  dust  of  dwellings.  Thus 
Bonone  observed  that  out  of  seventy  persons  injm-ed  by  the  faUing  of  a 
church  during  an  earthquake,  seven  were  attacked  by  tetanus.  Animals 
inoculated  with  the  dust  of  the  church  died  of  tetanus,  although  those 
inoculated  with  the  dust  of  another  church  did  not.  Again,  he  observed 
that  at  the  storming  of  the  church  in  Bajaido,  out  of  a  similar  number  of 
injured  persons  nine  died  of  tetanus,  and  in  three  he  recognised  the  specific 
bacillus.  He  then  experimented  with  dust  taken  fi-om  the  ruins,  and  found 
that  this,  when  inoculated  into  animals,  produced  the  disease  in  them,  the 
bacillus  bemg  also  found  in  pus  taken  from  the  inoculated  part. 

Although  it  appears  probable  that  tetanus  is  usually  induced  by  direct 
inoculation  with  soil  or  other  material  containing  Eosenbach's  bacillus, 
the  possibility  of  communicating  the  disease  from  one  human  being  to 
another  must  be  kept  in  mind,  a  case  having  been  recorded  where  the 
accoucheur,  being  in  attendance  on  a  case  of  trismus,  transmitted  the 
disease  to  a  woman  in  labour.  A  striking  instance  of  apparent  indirect 
transmission  from  one  animal  to  another  is  related  by  Langer,  in  which  all 
the  horses  castrated  by  the  same  ecraseur  died  of  tetanus,  while  after  boihng 
the  instrument  in  oil  no  others  died  or  were  afi'ected  from  its  use.  Such 
cases,  however,  are  rarely  seen,  and  many  observers  deny  the  possibility  of 
direct  contagion  altogether. 

The  infiuence  of  predisposition  cannot  be  denied,  and  doubtless  plays  a 
principal  part  in  the  development  of  tetanus.  Thus  the  negro  race  in  par- 
ticular, and  those  inhabiting  hot  chmates  generally,  are  believed  to  be  more 
susceptible  to  the  disease  than  dwellers  in  more  temperate  chmates,  and  what 
is  stiU  more  interestiug  is  the  observation  that  the  natives  of  hot  chmates  are 
far  more  liable  to  be  attacked  than  Europeans  resident  there.  In  the 
American  Civil  War  3-1  per  cent,  of  the  cases  occurred  amongst  the  negro 
troops,  who  fm-nished  only  2*7  per  cent,  of  the  total  number  of  wounds. 
Tetanus  is  specially  apt  to  occur  in  feeble  and  debilitated  individuals, 
although  the  robust  are  by  no  means  exempt,  and  it  is  most  hkely  to  occur,, 
particularly  in  the  case  of  wounds  received  on  the  field  of  battle,  after  sudden 
changes  of  weather,  such  as  alternations  from  heat  to  cold,  especially  if 
associated  with  moistm-e  of  soil  or  air.  Thus,  in  certaiu  tropical  climates, 
as  in  some  of  the  West  India  Islands  and  amongst  the  marshes  of  Cayenne, 
it  occurs  with  pecuhar  frequency,  the  most  trifling  scratches  or  punctures 
bemg  followed  by  the  disease.  Macleod  states  that,  after  some  of  the  Indian 
battles  when  the  woimded  lay  exposed  to  cold  nights  after  very  hot  days, 
tetanus  was  of  very  frequent  occurrence.     From  these  observations  it  seems 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  d75 

probable  that  the  soil  plays  a  double  part  in  the  aetiology  of  the  disease ;  since 
it  not  only  harbours  the  organism  which  is  necessary  for  its  production, 
but  may  also  in  certain  instances  directly  predispose  to  the  attacks  of  the 
bacillus  by  means  of  the  amount  of  moisture  it  contains,  or  the  amount  of 
heat  it  is  capable  of  absorbing  and  of  radiating. 

The  relation  of  tetanus  to  soil  is  of  such  interest  and  importance  that  it 
may  be  well  to  add  a  brief  record  of  some  cases  observed  by  Eiselberg  which 
he  had  the  opportunity  of  investigating  thoroughly.  The  first  is  that  of  a 
woman  in  whom  tetanus  occurred  after  a  compound  fracture,  the  wound 
having  been  much  contaminated  with  dirt.  Like  other  observers,  he  found 
that  neither  cultures  made  from  the  blood  nor  inoculations  of  blood  into 
animals  produced  any  effect.  He  found,  however,  the  typical  bacillus  in  pus 
from  the  wound,  and  succeeded  in  transmitting  the  disease  to  animals  by 
inoculations,  both  of  the  pus  itself  and  of  cultivations  obtained  from  it,  l>ut 
lie  was  unable  to  find  bacilli  in  either  blood  or  tissues.  His  second  case 
was  a  very  mild  one,  occurring  in  a  man  who  had  injured  his  finger,  the 
wound  being  contaminated  with  dirt.  Inoculation  experiments,  however, 
gave  no  results.  In  the  third  and  fourth  cases  he  was  again  successful  in 
carrying  on  the  disease  through  various  animals — in  the  one,  starting  inocu- 
lations after  the  death  of  the  patient  from  small  pieces  of  skin  removed  from 
the  edges  of  the  wound,  and  in  the  other  with  earth  from  a  cellar  in  which 
the  injury  was  received.  His  fifth  and  sixth  cases  v/ere  both  due  to  tetanus 
following  on  the  running  of  splinters  of  wood  into  the  hand,  and  in  each 
instance  the  splinter,  or  portions  of  it,  caused  an  attack  of  the  disease  in 
rabbits,  when  inserted  beneath  the  skin,  the  bacillus  being  recognised  m 
the  secretion  from  the  wounds  thus  caused. 

In  this  connection  it  is  interesting  to  note  that  the  last  four  cases  of  tetanus 
that  have  been  under  treatment  in  the  Norfolk  and  Norwich  Hospital  were 
all  due  to  wounds  caused  by  agricultural  implements,  such  as  a  pitchfork  and 
a  scythe.  Inoculation  experiments,  however,  were  of  course  out  of  the 
question,  and  unfortunately  no  search  for  the  specific  bacillus  was  made. 


Anthbax 

Malignant  pustule  or  anthrax  is  a  specific  disease  which  is  communi- 
cable to  man,  directly  or  indirectly  from  the  lower  animals ;  the  herbivora 
being  specially  susceptible  to  it.  It  would  appear  that  direct  contagion  from 
living  animals  affected  with  anthrax  seldom  or  never  happens,  although 
butchers,  slaughterers,  and  veterinary  surgeons  occasionally  become  infected 
in  this  way. 

Under  the  name  of  woolsorters'  disease,  a  form  of  anthrax  has  prevailed 
at  Bradford  and  other  places  for  many  years,  which  is  due  to  the  handling 
and  sorting  of  wool  and  hair  obtained  chiefly  from  Asia  Minor,  where  anthrax 
disease  is  rampant.  This  method  of  communication,  however,  will  not  now 
be  discussed,  as  a  full  account  will  be  found  in  another  section. 

Anthrax  appears  to  be  specially  prevalent  in  certain  countries  among 
animals  pastured  upon  damp  soils  containing  much  humus,  as,  for  instance, 
upon  peat  bogs,  and  near  the  borders  of  lakes  and  rivers  that  have  overflowed ; 
the  hottest  months  of  the  year,  particularly  August  and  September,  being 
those  during  which  it  is  most  frequent.  Bollinger  has  suggested  that  damp- 
ness of  soil  may  affect  the  prevalence  of  anthrax  by  affording  conditions 
favourable  for  the  growth  and  multiphcation,  apart  from  a  living  host,  of  the 
bacillus  which  is  the  cause  of  the  disease.  The  bacilh,  however,  only  exist 
in  the  soil  when  derived  from  a  previous  case  of  anthrax,  either  from  the 


376  BYGIENE 

excreta  or  discharges  of  a  diseased  animal,  or  from  the  dead  bodies  of  those 
which  have  succumbed,  and  which  have  been  carelessly  buried  or  left  to  decay- 
on  the  surface.  Pasteur  indeed  is  of  opinion  that  when  carcases  of  animals 
which  have  died  from  anthrax  are  buried,  the  development  of  bacilli  into 
spores  can  take  place  ui  the  soil,  and  that  these  spores  may  in  turn  be 
swallowed  by  earth-worms  and  be  carried  to  the  surface  and  deposited  in  their 
castmgs.  In  this  way  animals  pastured  on  such  soil  would  be  hable  to  become 
infected.  Koch  and  others  strongly  combat  this  view,  and  seeing  that  spores  are 
only  produced  in  presence  of  oxygen,  it  is  quite  probable  that  then*  formation 
would  not  take  place,  provided  the  animal  be  buried  without  being  opened  ; 
but  where  this  has  been  done  for  the  purpose  of  investigating  the  cause  of 
death,  it  would  appear  that  the  amount  of  oxygen  in  the  pores  of  the  soil 
may  be  sufficient  to  enable  sporulation  to  come  about.  Schmidt  Muhlheim 
has  recently  brought  forward  some  experiments  which  bear  somewhat  on 
this  point,  as  well  as  on  the  question  of  the  anthrax  bacillus  producing  spores 
in  the  meat  of  animals  afflicted  with  this  affection  at  the  time  they  were 
slaughtered.  He  inoculated  guinea-pigs  with  anthrax,  and  as  soon  as  death 
took  place  they  were  skinned,  and  then  the  hmbs  were  remove  and  placed 
in  the  incubator  at  a  temperature  of  39°  C.  The  surface  of  the  flesh  was 
soon  covered  wdth  a  whitish  film,  which  was  found  to  consist  exclusively  of 
anthrax  bacilh,  in  many  of  which  commencing  spore-formation  was  apparent. 
This  vigorous  growth  did  not,  however,  extend  beneath  the  surface,  as  within 
the  tissues  there  did  not  appear  to  be  more  bacilli  than  were  found  in  portions 
of  flesh  which  had  not  been  placed  in  the  incubator. 

The  immediate  burial  of  the  carcases  of  animals  dying  from  anthrax  has 
indeed  been  recommended  as  a  preventive  measure  against  further  extension 
of  the  disease  ;  since,  if  the  skin  be  intact  and  the  interment  be  performed 
at  a  sufficient  distance  beneath  the  surface,  the  spores  which  are  more  re- 
sistant do  not  put  in  an  appearance,  while  the  bacilli  themselves  apparently 
are  destroyed  after  a  varying  period  by  putrefactive  organisms,  which  being 
anaerobic  are  capable  of  flourishing  in  absence  of  oxygen.  But  even  supposing 
that  Pasteur's  theory  cannot  be  looked  upon  as  proved,  it  is  evident  that  the 
soil  may  readily  become  infected  from  the  discharges  of  moribund  animals. 
The  bacilh  find  sufficient  pabulum  in  decaying  animal  and  vegetable  matter 
on  the  surface,  and  having  free  access  of  oxygen,  spores  are  formed  in  them 
in  abundance,  by  which  in  turn  the  herbage  becomes  contaminated.  In  the 
event  of  the  meadows  becoming  flooded  the  spores  may  thus  become  carried 
over  the  adjoining  land,  and  may  even  gain  access  to  the  drinking  water, 
instances  of  infection  of  human  beings  having  apparently  been  traced  to  such 
a  som'ce. 

The  Bacillus  Anthracis 

The  specific  organism  of  this  disease  is  perhaps  the  one  among  those  of 
a  pathogenic  nature,  the  morphological  and  biological  characters  of  which 
have  been  most  completely  worked  out.  For  this  very  reason,  however,  the 
subject  will  be  found  to  be  presented  in  so  detailed  a  manner  in  the  bacterio- 
logical section  of  this  work  that  only  the  merest  sketch  will  be  attempted 
in  this  place.  The  bacillus  was  first  discovered  by  PoUender  in  1849,  but 
Davaine  was  the  first  to  maintain  that  this  organism  was  the  essential  cause 
of  anthrax  in  its  various  forms.  The  bacilh  consist  of  straight,  slightly  bent, 
or  curved  rods,  of  comparatively  large  size,  with  square  extremities  ;  they 
often  cohere  by  their  ends,  this  being  specially  noticeable  when  they  are 
cultivated  artificially.  Under  these  circumstances  they  may  grow  into  long 
filaments  in  the  interior  of  which  bright  granules  appear. 

These  granules  are  spores,  the  appearance  of  which  is  of  considerable 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  377 

importance,  seeing  that  they  are  much  more  resistant  than  the  rods  them- 
selves, being  able  to  withstand  desiccation  and  a  considerable  amount  of  heat, 
while  under  favourable  circumstances  they  are  capable  of  again  giving  rise 
to  the  bacillary  form.  Spores  only  form  when  there  is  free  access  of  air, 
but  multiplication  of  the  bacilli  also  takes  place  by  a  process  of  fission. 

The  possibility  of  attenuating  the  infecting  power  of  pathogenic  organisms 
was  first  established  in  the  case  of  anthrax,  it  being  found  that  these  bacilli, 
which  thrive  best  in  an  alkaline  medium,  become  weakened  when  cultivated 
for  about  twenty  days  in  a  neutral  nutrient  fluid  kept  at  a  temperature 
somewhat  higher  than  that  of  the  body.  Animals  inoculated  with  such  a 
culture  pass,  as  Pasteur  has  shown,  through  a  mild  form  of  the  disease, 
which  protects  against  a  second  attack,  more  complete  immunity  being 
■obtained  by  the  subsequent  inoculation  of  a  more  virulent  material.  The 
protection  thus  afforded  appears,  however,  to  last  for  a  certain  time  only, 
when  further  treatment  in  a  similar  manner  becomes  necessary. 

Klein  has  also  shown  that  the  virulence  of  the  bacillus  may  be  lowered 
by  passing  it  through  certain  animals.  Thus  cattle  and  sheep  may  be 
protected  for  a  time  by  inoculating  them  with  the  blood  of  mice  which  have 
been  inoculated  and  killed  with  a  virulent  cultivation.  On  the  other  hand, 
.a  bacillus  thus  attenuated  may  once  more  be  made  to  regain  its  virulence 
for  sheep  by  first  passing  it  through  the  system  of  a  guinea-pig. 

Hankin  has  recently  announced  a  new  method  of  creating  immunity 
against  anthrax  by  means  of  an  albumose  isolated  from  bouillon  anthrax 
cultures,  where  it  is  formed  as  the  result  of  the  vital  activity  of  the  bacilh. 
This  albumose  is  obtained  by  filtering  the  nutrient  fluid  through  a  Chamber- 
land  filter  of  unglazed  porcelain  to  remove  the  micro-organisms  and  treating 
with  absolute  alcohol.  He  thus  precipitates  the  albumose  as  a  powder,  which 
is  redissolved  for  use. 

By  inoculation  with  this  chemical  material  rabbits  and  guinea-pigs  have 
loeen  enabled  to  resist  the  action  of  virulent  anthrax  cultivations.  More 
powerful  still  is  an  alkaloid  which  Sidney  Martin  has  obtained,  also  from  the 
mitrient  material  in  which  the  bacilli  have  been  grown,  and  it  would  appear 
more  than  likely  that  Koch's  '  tuberculin  '  derived  from  cultivations  of 
"tubercle  bacilli  is  in  reality  a  solution  of  a  somewhat  similar  substance.  If 
"this  be  so,  it  is  not  impossible  that  in  the  near  future  we  may  possess  the 
power  of  preventing  the  incursions  of  numerous  diseases,  to  which  not  only 
the  lower  animals  but  man  also  is  liable,  by  means  of  a  system  of  pro- 
jective vaccinations  of  one  and  another  chemical  substance. 

Canceb 

There  appears  to  be  no  doubt  that  the  number  of  deaths  from  cancer,  using 
this  term  as  a  general  designation  for  all  malignant  new  growths,  is  gradually 
increasing  in  number  in  this  country  year  by  year.  The  Eeport  of  the 
Eegistrar-General  for  1889  shows  that  there  were  18,654  deaths  from  this 
•cause  in  that  year,  a  number  which  is  in  the  proportion  of  643  to  each  million 
persons  living,  and  which  shows  a  further  increase  upon  the  ever-growing 
rates  previously  recorded.  Some  of  this  increase  is  most  certainly  to  be 
attributed  to  increased  accuracy  in  statement  of  cause  of  death,  and  to  the 
system  introduced  some  years  back  of  writing  for  further  information  in  cases 
where  some  vague  cause,  such  as  '  tumour,'  has  been  given  in  the  original 
■death-certificate ;  a  system  which  added,  for  instance,  in  the  year  under 
-consideration  no  less  than  421  deaths  under  the  heading  of  cancer.  Never- 
:theless,  in  face  of  the  constant  and  great  growth  of  mortality  under  this 


378  HYGIENE 

heading,  and  the  expressed  behef  of  medical  practitioners  specially  engaged 
in  dealing  with  this  class  of  diseases,  that  they  are  really  becoming  more  and 
more  common,  it  seems  scarcely  possible  to  maintain  the  optimistic  view 
that  the  whole  of  the  apparent  increase  can  be  explained  as  mere  matter  of 
registration  ;  and  it  must  be  admitted,  as  at  any  rate  highly  probable,  that  a 
real  increase  is  taking  place  in  the  death-rate  from  these  malignant  affections. 

Whether  an  inherited  tendency,  as  distinct  from  influence  of  locality, 
have  anything  to  do  with  the  causation  of  neoplastic  growths  or  not  is  a 
very  difficult  question ;  but  it  needs  to  be  pointed  out  that  neither  a  con- 
siderable proportion  of  cases  with  a  family  history  of  similar  disease,  nor 
even  a  considerable  proportion  of  cases  with  a  history  of  such  affliction 
among  the  direct  progenitors,  is  of  itself  sufficient  evidence  of  inheritance.. 
For  seeing  that  one  out  of  twenty- one  males  and  one  out  of  twelve  women 
who  reach  the  age  of  thirty-five  die  eventually  of  malignant  disease,  it  followa 
by  the  law  of  iDrobabilities  that,  on  an  average,  in  one  of  three  cases  either  a. 
parent  or  a  grandparent  will  have  died  of  such  an  affection.  Supposing  such 
parents  and  grandparents  to  have  died  after  tliirty-five  years  of  age,  and  the 
proportion  will  be  still  higher  if  the  circle  of  relatives  be  extended  so  as  to 
include  not  only  these  direct  progenitors,  but  collateral  relatives,  such  as 
uncles  and  aunts.  Seeing,  however,  that  such  a  tendency  if  it  exist  would 
not,  as  a  rule,  manifest  itself  till  after  the  usual  age  of  marriage  and  partu- 
rition, it  foUows  that  the  tendency  would  be  likely  to  spread  wider  and  wider 
among  the  population,  there  being  no  opportunity,  as  may  occur  in  tubercular 
phthisis,  of  weeding  out  by  early  death  from  the  candidates  for  matrimony 
those  who  are  most  seriously  liable  to  this  disease. 

With  regard  to  the  part  played  by  telluric  and  topograpliical  conditions 
in  the  aetiology  of  cancer,  Haviland  states  as  his  opmion  that  m  countries 
having  a  high  mortality  from  this  disease  the  tributaries  of  rivers  flow  from 
soft,  marshy,  and  easily  disintegrated  rocks  into  sheltered  valleys  through 
which  the  main  rivers  flow.  During  times  of  heavy  rainfall  these  rains  in- 
variably flood  the  adjacent  districts,  and  generally  have  their  water  coloured 
by  alluvial  matter  in  suspension.  He  further  cites  the  Thames  Valley  as  a 
typical  cancer  district  in  all  these  respects.  From  the  statistics  brought 
forward  it  would  appear  that,  as  is  also  the  case  with  phthisis,  cancer  does 
not  thrive  on  a  high  and  dry  soil ;  but  this  statement  must  be  received  with 
caution  in  connection  with  the  fact  that,  although  extensive  drainage  opera- 
tions have  been  carried  out  in  recent  years,  the  death-rate  from  cancer  does 
not  show  any  corresponding  decrease. 

Such  generalisations  are,  however,  opposed  by  the  fact  that  in  Norway 
cancer  occurs  mostly  in  the  mountainous  districts  and  at  considerable  eleva- 
tions, to  some  extent,  no  doubt,  along  the  shores  of  the  fjords,  but  least  of 
all,  as  Hirsch  has  shown,  on  the  open  coast.  Again,  in  Mexico  the  high  table- 
land is  more  subject  to  cancer  than  the  low  plains.  Obviously,  therefore, 
Haviland's  conclusions,  even  if  true  for  the  United  Kingdom,  are  by  no  means 
universally  applicable. 

Calculus 

In  considering  the  connection  of  calculous  disease  with  soil,  it  is  im- 
portant in  the  first  place  to  see  how  the  incidence  of  the  disease  is  affected 
by  geographical  distribution,  and  then  to  ascertain,  if  possible,  whether  any 
common  soil-condition  can  be  found  in  those  districts  in  which  calculus  is 
most  prevalent. 

The  geographical  distribution  of  calculus,  or  stone  in  the  bladder,  is  a 
subject  which  has  perhaps  been  better  worked  out  than  in  the  case  of  any^ 


THE  INFLUENCE  OF  SOIL   ON  HEALTH 


STQ' 


other  disease.  In  all  parts  of  the  world  calculous  diseases  are  known,  but 
in  certain  jDortions  of  the  globe  they  are  much  more  common  than  in  others. 
This  is  notably  the  case  in  India,  hardly  any  part  of  which  is  exempt,  although 
the  northernmost  districts,  particularly  the  North- West  Provinces,  are  those 
which  suffer  most  severely  in  this  respect.  Curiously  enough,  it  is  apparently 
only  of  recent  years  that  the  malady  has  become  so  prevalent  in  India,  since 
Scott,  writing  in  1816,  asserted  that  that  country  had  the  reputation  of 
enjoying  a  special  exemption  from  calculus. 

In  this  country  the  evidence  derived  from  hospital  statistics,  from  death- 
registration  and  other  sources,  points  to  a  special  prevalence  of  the  disease 
in  the  eastern  and  southern  counties,  while  of  these  it  is  most  common  in 
Norfolk.  The  following  table  compiled  by  Cadge,  of  Norwich,  from  the  death- 
returns  for  the  five  years  18G7-71,  giving  the  proportion  of  inhabitants  in 
the  several  counties  for  each  death  from  stone  during  that  period,  shows  this 
fact  very  clearly  : — 

Deaths  from  Urinary  Calculus  in  English  Counties  during  Five,  Years 


Eastern  Counties     . 

1  in  63,475  pop. 

Southern  MidLands 

1  in    86,367  pop 

Norfolk    . 

„    42,744     „ 

Hunts    . 

,,      59,137     „ 

Suffolk     . 

.       „    67,081     „ 

Bucks     . 

„      61,335     „ 

London   . 

„    70,099     „ 

Herts 

„      68,250     „ 

Wales  and  Monmouth 

„    77,202     „ 

Camb.     . 

„      69,845     „ 

Yorkshire 

»    77,520     „ 

Northampton . 

„      82,-525     „ 

West  Eiding    . 

„    61,405     „ 

Western  Midlands. 

„    128,216     „ 

N.    and    E.  Eiding 

Warwick 

„      65,670     „ 

and  York  . 

•       ,,    71,475     „ 

Shropshire 

„      66,750     „ 

South-Eastern  Counties 

„    83,978     „ 

Worcester 

.       „      73,100     „ 

Kent 

„    60,585     „ 

Stafford  . 

.       „      76,965     „ 

Sussex 

.       „    61,139     „ 

Northern  Counties 

„    191,875     „ 

Berks 

„    93,470     „ 

South- Western  Counties 

,       „    203,985     „ 

Northern  Midlands . 

„    85,959     „ 

North- Western  Countie 

3       „    209,681     „ 

Leicestershire  . 

„    64,115     „ 

It  is  probable,  however,  that  the  local  incidence  of  the  disease  in  Norfolk 
is  even  greater  than  v/ould  appear  from  these  statistics,  since  death  returns 
have  only  a  limited  value  in  deciding  this  question,  it  being  obvious  that, 
where  calculus  is  of  frequent  occurrence,  operators  will  acquire  more  skill  in 
its  treatment,  and  consequently  the  number  of  deaths  from  operation  or  from 
non-relief  of  the  condition  will  be  relatively  fewer.  It  should  also  be  borne 
in  mind  that  death  statistics  may  be  open  to  grave  fallacy  from  errors  of 
diagnosis  made  in  referring  death  to  this  particular  cause. 

In  Scotland  the  malady  is  for  the  most  part  somewhat  more  frequent 
than  in  England,  and  this  appears  to  be  still  more  the  case  if  mortahty 
statistics  be  taken  for  purposes  of  comparison.  Cadge,  however,  has  shown 
that  this  can  in  part  be  accounted  for  by  the  facts  that  not  only  are  many 
less  cases  admitted  into  hospital  in  Scotland  than  in  England,  but  also  that 
the  proportion  operated  on  is  much  fewer  than  in  this  country,  so  that  in  this 
way  the  mortality  from  calculus  is  increased. 

Curiously  enough,  Ireland,  on  the  contrary,  enjoys  an  almost  complete 
immunity  from  the  disease,  and  has  done  so  for  a  lengthy  period,  as  is  shown, 
from  the  earliest  authentic  statistics  on  the  subject.  Thus  Yelloly,  writing 
in  1845,  states  that,  although  he  had  inquired  very  thoroughly  into  the  sub- 
ject, he  found  that  not  a  single  case  of  operation  for  stone  had  occurred  fi'om 
first  to  last  in  the  hospitals  supplying  the  three  and  a  half  millions  of  people 
in  Antrim,  Armagh,  Londonderry,  Donegal,  Fermanagh,  Tyrone,  Carlo w,. 
Kildare,  Kilkenny,  Longford,  Louth,  Wicklow,  Clare,  Kerry,  Galway,  Eos- 
common,  Tipperary,  and  Mayo,  and  that  no  case  had  come  to  the  knowledge 


380  HYGIENE 

of  practitioners  among  the  poorer  classes  of  the  people  in  those  counties. 
For  the  whole  of  the  rest  of  the  country  the  result  of  his  investigations 
showed  that  the  average  number  of  operations  was  about  six  every  year. 

Other  European  countries  enjoying  a  like  immunity  are  Switzerland, 
Greece,  and  in  the  more  northern  districts  of  Norway,  Sweden,  and  Denmark, 
Holland,  on  the  other  hand,  has  held  the  unenviable  notoriety  of  supplying 
the  largest  number  of  cases  of  calculous  disease  in  this  part  of  the  world. 
This  fact  comes  out  prominently  in  the  surgical  writings  of  the  seventeenth 
and  eighteenth  centuries ;  and  although  the  prevalence  of  the  malady  has 
decreased  somewhat  of  recent  years,  Janssens  states  that  it  is  still  relatively 
common  in  Belgium. 

Many  of  the  earlier  writers  on  this  subject,  from  a  comparison  of  those 
parts  of  Europe  and  England  where  the  disease  manifests  itself  to  the 
largest  extent,  arrived  at  the  conclusion  that  chmatic  influences  likely  to 
affect  the  soil,  more  particularly  cold  and  damp,  were  of  great  ^etiological 
importance  in  the  production  of  the  malady,  Crosse,  in  his  treatise  on  the 
formation  of  the  urinary  calculus,  laying  special  stress  on  the  cold  and  wet 
chmate  of  Norfolk  as  accounting  for  the  gi'eat  frequency  of  stone  in  that 
comity.  The  results  of  later  investigations,  however,  do  not  support  this 
theory.  Thus  Cadge  shows  that  there  are  many  parts  of  the  North  of 
Scotland  as  well  as  of  Ireland  where  the  climatic  influences  are  the  same, 
and  yet  there  is  none  of  the  disease,  and  that  in  Norfolk  itself  stone  is  more 
frequent  in  inland  parishes  than  in  places  on  the  coast  which  are  least 
favourably  situated  as  regards  climate.  In  this  connection  it  is  also  worthy 
of  note  that  in  many  places  where  stone  is  endemic  the  areas  affected  are 
often  very  definitely  bounded,  so  that  the  malady  may  be  extremely  rare  in 
closely  adjoinmg  districts,  although  the  conditions  as  regards  climate  are 
identical. 

Again  certain  countries  which  have  a  decidedly  wet  and  cold  climate,  such 
as  Norway  and  Sweden,  are  practically  exempt  from  the  disease;  while,  on  the 
other  hand,  it  has  been  shown  that  Italy  and  Spain,  for  instance,  and  many 
parts  of  Southern  Asia  are  eminently  liable  to  calculus. 

Another  hypothesis  which  has  received  a  considerable  amount  of  support 
attributes  the  excessive  prevalence  of  calculous  diseases  in  certain  districts 
to  the  hardness  of  the  water  which  is  used  for  drinking  purposes  by  the 
inhabitants.  Seeing  that  this  will  depend  in  turn  on  the  nature  of  the  soil 
from  which  the  water  is  obtained,  many  observers  have  come  to  the  conclusion 
that  stone  is  more  common  on  certain  geological  formations,  and  particularly 
where  chalk  is  found  in  abundance.  This  theory,  which  has  received  the 
support  of  Sexton  and  others,  who  do  not,  however,  believe  that  the  water- 
supply  has  any  causative  influence  on  the  disease,  would  certainly  appear 
to  be  worthy  of  attention,  although  of  late  so  many  exceptions  to  the  rule 
have  come  to  light  that  it  cannot  now  be  considered  to  be  of  more  than 
lunited  application. 

The  arguments  both  for  and  against  this  view  are  so  well  summarised  by 
Hirsch  that  it  may  be  well  to  quote  his  own  words  :  '  When  we  survey  the 
distribution-area  of  the  disease,  we  certainly  discover  an  imposing  array  of 
facts  that  can  be  used  in  support  of  that  doctrine,  such  as  the  prevalence  of 
the  disease  on  the  calcareous  and  dolomite  soil  in  the  basins  of  the  Don  and 
Volga  in  Kussia  (to  which  Becketow  has  lately  called  attention),  on  the 
chalk  soil  of  the  eastern  counties  of  England,  and  on  the  Jurassic  limestone 
of  the  Swabian  Alp  in  Wiirtemberg,  beyond  the  limits  of  which,  as  on  the 
Keuper  of  the  Necker  VaUey,  or  on  the  Muschel  Kalk  (Triassic  formation)  of 
Franconia,  the  Spessart,  and  the  Khon,  calculus  is  very  unusual;  further,  in 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  381 

some  parts  of  Italy  with  a  soil  of  limestone,  such  as  the  provinces  of  Brescia 
and  Cremona,  on  the  chalk  and  limestone  of  Syria,  or  the  Jurassic  limestone 
of  Montreal,  in  a  part  of  Maine  with  the  same  formation,  and  in  Lexington, 
Ky.,  which  stands  on  more  recent  hmestone.  But  this  geographical  agree- 
ment of  a  number  of  centres  of  calculus,  very  striking  though  it  be,  loses  no 
small  part  of  its  significance  when  we  go  further  afield.  We  have  to  take 
into  account,  on  the  one  hand,  that  the  disease  is  indigenous  to  an  equal 
extent  on  other  kinds  of  soil,  such  as  the  basaltic  trap  formations  in  several 
parts  of  the  Deccan,  the  basaltic  and  volcanic  tufa  in  Mauritius  and  Reunion, 
the  alluvium-covered  granite  of  Canton,  the  transition  rocks  of  North  Wales, 
the  carboniferous  limestone  of  Yorkshire,  the  Zechstein  of  Altenberg,  the 
red  sandstone  and  variegated  sandstone  of  the  Eajestan  States  and  other 
parts  of  Hindostan,  the  Keuper  and  Muschel  Kalk  of  the  plateau  of  Lorraine, 
and  the  clay  soil  of  Reval  and  Ostend.  On  the  other  hand,  we  have  to  bear 
in  mind  that  large  territories  belonging  to  the  more  recent  limestone,  chalk, 
or  Jurassic  formations  are  almost  entirely  exempt  from  the  malady ;  such 
as  the  limestone  coast-margin  of  Barbadoes  and  other  West  India  Islands, 
the  Jurassic  formation  of  the  whole  of  Western  Switzerland  and  other  parts- 
of  that  country,  and  many  parts  of  England.' 

It  is  difficult  also  to  see  why,  if  there  be  some  such  common  cause  pre- 
disposing to  the  occurrence  of  stone  in  the  bladder,  the  composition  of  the 
concretion  should  not  in  all  cases  be  the  same.  No  doubt,  when  once  a  stone 
has  formed  it  may  increase  in  size  by  the  deposition  of  phosphatic  layers,  due 
to  an  ammoniacal  state  of  the  urine  resulting  from  cystitis,  particularly  in 
elderly  persons,  who  may  not  be  able  to  thoroughly  evacuate  the  bladder. 
Apart  from  this,  however,  we  find  that  the  composition  of  the  nucleus  varies 
in  different  parts  of  the  world,  even  when  the  conditions  of  soil  are  the  same. 
Thus  Vandyke  Carter  states  that  the  proportion  of  calculi  with  a  uric  acid 
or  urate  of  ammonium  nucleus  in  England  is  72  per  cent.,  while  in  India 
it  is  only  56 ;  an  oxalate  of  calcium  nucleus,  on  the  other  hand,  being  more 
than  twice  as  frequent  in  India  as  in  England,  a  similar  preponderance 
having  also  been  found  in  Wiirtemberg  and  Moscow.  It  is  possible  that 
oxalate  may  in  some  eases  develop  from  uratic  calcuh,  but  it  is  impossible 
to  account  for  the  frequency  of  their  occurrence  in  certain  localities  m  this 
way.  Many  suggestions  have  been  brought  forward,  ascribing  the  differ- 
ences to  peculiarity  of  race,  of  constitution  of  diet,  with  exposure  to  prevalent 
easterly  winds,  and  the  like,  but  probably  but  little  weight  can  be  attached  to 
any  of  these  supposed  factors,  the  exact  setiology  of  calculous  disease  having 
yet  to  be  worked  out. 

ElCKETS 

Many  are  the  attempts  that  have  been  made  to  define  a  cause  for  this 
disease.  Among  those  which  have  from  time  to  time  been  suggested  are 
prolonged  suckling  or,  on  the  other  hand,  prematiu'e  weaning  ;  the  effect  of 
indigestible  and  insufficient  food  or  of  a  deficiency  in  it  of  Hme  and  of  phos- 
phoric acid.  Experimental  evidence  has  been  invoked  in  support  of  these 
various  theories,  but  the  results  have  not  been  such  as  to  give  definite 
support  to  any  one  of  them.  All  authorities  are  agreed  that  the  morbid 
process  is  fundamentally  a  disorder  of  nutrition,  a  cause  for  which  must 
probably  be  sought  for  either  in  an  hereditary  taint  or  in  the  manner  of 
bringing  up,  defective  or  improper  food,  if  it  bear  any  import,  acting,  however, 
only  indirectly  by  producing  general  weakness. 

A  noteworthy  point  to  which  attention  has  not  perhaps  been  sufficiently 
directed  comes  out  when  we  examine  into  the  geographical  distribution 


882  HYGIENE 

of  the  disease.  Tliis  is  that,  while  in  temperate  regions  it  is  moderately 
common,  tropical  and  subtropical  countries  are  almost  free  from  it,  particu- 
larly in  its  severer  forms.  There  is,  in  fact,  abundant  evidence  that,  both  in 
amount  and  severity  of  type,  the  disease  stands  in  a  definite  relation  to 
climate,  and  that,  as  Hirsch  has  stated,  countries  with  a  cold  and  wet  climate, 
subject  to  frequent  changes  in  weather,  such  as  Holland,  many  parts  of 
England,  the  North  German  plain,  the  mountainous  regions  of  Central  and 
Southern  Germany,  and  the  plains  and  mountainous  districts  of  Northern 
Italy,  if  they  are  not  the  exclusive  seat  of  rickets,  are  at  all  events  its  head- 
quarters. It  wQuld  appear,  moreover,  that  of  the  districts  mentioned  the 
disease  is  more  prevalent  wherever  the  character  of  the  climate  is  specially 
dependent  on  the  nature  of  the  soil ;  as,  for  instance,  in  the  neighbourhood  of 
marshy  plains  or  in  valleys  which  are  deep  and  damp  and  liable  to  frequent 
floods. 

Oppenheim,  indeed,  arguing  from  this  preference  exhibited  by  the  disease 
for  wet  and  marshy  districts,  and  fi-om  the  fact  that  enlargement  of  the  spleen 
is  not  unfrequently  found  in  rickety  children,  has  been  led  to  the  conclusion 
that  the  disease  is  in  some  way  related  to  a  malarial  taint.  There  is,  however, 
little  or  nothing  to  be  found  in  support  of  this  \dew,  and,  indeed,  it  would 
appear  that  in  some  instances  at  any  rate  rickets  is  least  common  just  in 
those  very  districts  where  malaria  is  worst. 

On  the  other  hand,  rickets  is  of  rare  occurrence  at  elevated  sites,  particu- 
larly where  the  soil  is  also  dry,  even  though  at  the  same  time  the  hygienic 
conditions  among  which  the  population  live  may  be  the  reverse  of  favourable. 
From  a  consideration  of  these  observations  it  would  appear,  then,  that  a  line 
of  treatment  which  might  be  expected  to  be  attended  with  beneficial  results 
would  consist  in  the  removal  of  children  subject  to  this  disease  to  a  warmer 
and  drier  climate  for  a  time.  Unfortunately  in  the  majority  of  cases,  such  a 
complete  change  is  usually  impossible,  and  recourse  must  therefore  be  had 
to  care  in  feedmg,  combined  with  warm  clothing,  exercise  in  the  open  air, 
and  medical  treatment  of  a  more  or  less  empirical  kind. 

GOITEE   AND   CbETINISM 

Although  these  diseases,  and  more  particularly  goitre,  occur  in  widely 
different  portions  of  the  globe,  it  is  a  remarkable  fact  that  in  each  locality 
when  they  are  endemic  the  incidence  is  mainly  on  a  small  circumscribed  tract 
of  country,  the  surrounding  districts  being  often  completely  free.  There  is, 
then,  an  mtimate  relation  of  these  diseases  to  locality,  and  probably  there- 
fore to  the  natm-e  of  the  soil  or  the  soil  contents,  Klebs  having  shown  that 
atmospheric  influences,  such  as  the  amount  of  sunlight,  air,  and  so  on,  play 
but  a  subordinate  part  in  the  matter,  as  if  otherwise  these  affections  would 
not  be  so  limited  to  particular  spots  as  is  invariably  the  case. 

It  is,  moreover,  a  well-recognised  fact  that  healthy  persons  coming  into 
goitrous  districts  from  places  where  the  disease  is  unknown  not  unfrequently 
contract  the  malady,  sometimes  after  a  very  short  stay  only ;  while,  on  the 
other  hand,  removal  from  goitrous  centres  has  been  found  to  have  an  influ- 
ence for  good,  either  in  preventing  the  occurrence  or  in  arresting  the  further 
development  of  the  disease.  A  further  not  unimportant  point  is  found  in  the 
occurrence  of  goitre  among  domestic  animals,  such  as  horses,  mules,  goats, 
sheep,  pigs,  cats,  and  dogs  ;  a  fact  Avhich  was  Imown  to  Pliny,  and  which  has 
been  amply  substantiated  by  niimerous  observers  since  his  day. 

What  are  the  precise  conditions  of  soil  common  to  all  the  various  centres 
of  goitre  and  cretinism,  and  which  are  concerned  in  the  production  of  these 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  383 

nearly  related  diseases,  is,  however,  an  exceedingly  difficult  question.  Certain 
it  is,  at  any  rate,  that  the  degree  of  elevation,  or  the  configuration  of  the 
.ground,  has  no  influence  as  an  setiological  factor,  seeing  that,  although  per- 
haps mountainous  districts  are  more  frequently  affected  than  lower  lying 
tracts  of  country,  and  that  in  coast  regions  goitre  is  apparently  unknown, 
nothing  further  can  be  definitely  stated  in  this  respect  which  can  be  shown 
to  be  of  universal  application  with  regard  to  the  various  situations  in  which 
goitre  is  known  to  occur.  The  same  remarks  will  apply  to  the  theory  first 
propounded  by  Saussure,  and  which  has  received  a  certain  amount  of  support, 
namely,  that  the  spots  of  greatest  intensity  are  to  be  found  in  deep  dark  valleys, 
where  soil  and  air  alike  are  damp,  since  innumerable  instances  could  be  ad- 
duced of  wide  tracts  of  level  country  which  suffer  to  quite  a  similar  extent, 
even  where  the  soil  is  of  the  driest.  A  wet  or  marshy  soil  will  be  likely 
to  be  prejudicial  to  the  health  of  those  living  upon  it,  and,  therefore,  it  is 
likely  that  a  change  for  the  better  in  this  respect  may  become  apparent  after 
the  effectual  drying  of  the  soil  by  subsoil  drainage  and  the  like.  In  this 
manner,  no  doubt,  may  be  explained  the  decrease  in  the  amount  of  goitrous 
disease  which  has  occurred  of  late  in  certain  situations  which  formerly  were 
more  subject  to  it  than  at  present,  the  improved  hygienic  conditions  by  im- 
proving the  health  of  the  population  having  rendered  them  less  liable  to 
the  incursions  of  the  disease. 

We  are  thus  brought  back  to  the  conclusion  that  there  must  be  some 
connection  between  the  geological  and  mineralogical  character  of  the  soil 
and  the  endemic  occurrence  of  these  affections,  but  the  discrepancies  of  opinion 
between  the  various  observers  who  have  investigated  the  subject  afford  but 
little  ground  for  the  foundation  of  anything  like  a  dogmatic  assertion  on  the 
subject.  As  a  matter  of  fact,  it  would  appear  that  sufficient  care  has  not 
been  bestowed  on  the  determination  of  the  true  geological  conditions  of  the 
particular  localities  under  consideration,  especially  as  it  would  be  necessary 
to  investigate  not  only  the  characters  of  the  upper  layer  of  the  soil,  but  of 
the  subjacent  strata  also,  since  not  only  may  they  be  very  different  from  the 
surface  soil  above,  but  they  may  influence,  to  a  much  greater  extent,  the 
composition  both  of  the  air  and  water  of  the  district. 

A  view  that  has  much  to  be  said  in  its  favour,  and  which,  down  to  the 
present  day,  has  been  accepted  by  many  observers,  is  that  which  supposes 
that  the  use  of  water  containing  certain  mineral  constituents  in  considerable 
quantity  plays  the  chief  part  in  the  genesis  of  goitre.  Thus  in  many  parts 
of  the  world,  so-called  '  goitre  springs '  are  to  be  found  which  have  the  popu- 
lar reputation  of  causing  the  appearance  of  the  disease  in  those  who  drink 
of  them  ;  and  so  firmly  rooted  is  the  belief  that  there  are  numerous  records 
of  malingering,  especially  soldiers  desirous  of  escaping  active  service,  having 
taken  the  water  with  the  hope  of  inducing  an  attack. 

As  to  the  exact  nature  of  the  ingredients  of  the  water  which  would  appear 
to  possess  this  power  for  ill,  there  is  great  diversity  of  opinion,  but  seeing 
that  the  nature  of  the  water  must  in  time  depend  on  that  of  the  soil  from 
which  it  springs,  or  over  which  it  flows,  it  might  be  supposed  that  careful 
examination  of  the  constituents  of  the  soil  in  affected  areas  might  enable  us 
to  decide  the  point ;  unfortunately  up  to  the  present  no  such  successful 
result  has  been  obtained.  Many  suspected  goitre  springs  contain  a  large 
amount  of  carbonate  of  calcium  or  gypsum  dissolved  in  the  water,  and  thus 
the  idea  arose  that  endemic  centres  of  goitre  were  to  be  sought  for  in  places 
where  there  was  a  limestone  soil.  On  attempting  to  put  this  theory  to  the 
proof  accurate  examination  of  the  soil  has  undoubtedly  furnished  a  consider- 
able amount  of  corroborative  evidence  on  the  point.     Thus  McClelland,  who 


884 


HYGIENE 


instituted  a  most  thorough  iuqiiiry  into  the  subject  in  the  provinces  of  Ku- 
maon,  on  the  slope  of  the  Himalaya,  records  the  result  as  follows : — 

'  In  ninety- one  villages  situated  on  granite  and  gneiss,  hornblende  slate 
and  mica  slate,  clay  slate,  green  sandstone,  granitine,  and  silicious  sandstone, 
having  an  aggregate  population  of  5,383,  there  were  twenty-nine  goitrous 
jjersons  and  no  cretins  ;  whereas  in  thirty-five  villages,  on  Alpine  limestone 
(i.e.  Jurassic  limestone  and  Zechstein),  having  an  aggregate  population  of 
1,1  GO— 390  cases  of  goitre  were  found  and  thirty-four  of  cretinism.'  These 
statistics  have  received  support  from  Billiet  and  others,  who  asserted  that  in 
numerous  instances  in  which  adjoining  districts  were  found  to  show  a  strik- 
ing difference  in  the  extent  to  which  goitre  was  prevalent  the  state  of  the 
soil  was  obviously  the  determining  factor  in  the  one  direction  or  the  other, 
seeing  that  apparently  an  affected  district  might,  in  all  other  respects,  be  under 
absolutely  similar  conditions  to  an  adjacent  spot  where  the  disease  was  un- 
known. 

A  more  extended  series  of  observations  soon  showed,  however,  that  this 
theory  required  modification,  and  the  balance  of  opinion  veered  round  to  the 
hypothesis,  originally  put  forward  by  Zambroin  in  1825,  and  later  brought  into 
notice  independently  by  Grange,  that  the  question  did  not  depend  on  the 
presence  of  limestone  itself  so  much  as  on  the  amount  of  magnesium  salts 
combined  with  it,  goitre  being  found  to  the  maximum  extent  in  persons  living 
on  a  soil  of  magnesian  limestone  or  dolomite.  '  However  various  the  ele- 
vation, the  configuration,  and  the  formations  '  of  the  regions  investigated 
'  might  be,  an  unvarying  factor  in  them  all  was  the  presence  of  magnesia  in 
the  rock,  whether  it  occurred  in  the  form  of  magnesia  containing  silicates  (as 
particularly  in  gneiss  and  granite  and  hornblende  rocks)  or  in  the  form  of 
dolomite ;  and  it  was  the  absence,  or  the  somewhat  scanty  or  infrequent 
occurrence,  of  magnesia  in  the  younger  Jurassic  rocks,  in  the  chalk,  and  on 
the  Tertiary  formations  that  explained  the  immunity  of  localities  in  the  soil 
of  which  these  predominated.' 

Striking  as  is  the  manner  in  which  this  theory,  so  ably  developed  by 
Grange,  fits  in  with  the  results  of  observation  in  various  parts  of  the  world 
most  widely  separated  from  one  another,  such  as  Central  Europe,  Oudh,  and 
Brazil,  it  is  evident  that  it  cannot  be  considered  as  by  any  means  of 
universal  application.  Thus  Thomson  and  others  have  called  attention  to 
the  fact  that,  although  in  New  Zealand  large  masses  of  magnesian  limestone 
lie  exposed  in  the  Northern  Island,  where  live  by  far  the  greater  part  of  the 
native  population,  goitre  is  a  disease  entirely  unknown  among  them. 

Yet  another  theory,  apparently,  however,  more  untenable  than  the  older 
ones  it  challenges,  is  due  to  Saint  Lager,  who,  as  the  result  of  a  most  com- 
prehensive study  of  the  geological  characters  of  the  soil  in  all  parts  of  the 
world,  as  far  as  they  could  be  ascertained,  came  to  the  conclusion  that  the 
results  of  former  observers  as  to  the  importance  of  the  presence  of  magnesia 
was  capable  of  explanation  in  another  manner.  According  to  his  view,  goitre 
or  cretinism  is  prevalent  in  those  districts  only  where  there  is  an  amount 
of  metal-yielding  rock  to  be  found,  the  undoubted  connection  traced  by 
others  between  the  extent  of  the  disease  and  the  amount  of  magnesia  in  the 
soil  being  due,  in  his  opinion,  to  the  fact  that  limestone  rock  frequently  con- 
tains sulphide  of  iron.  Iron,  however,  is  not  the  only  metal  producing  this 
result,  as  the  presence  of  copper  pyrites  might,  he  believed,  produce  a  similar 
effect. 

From  what  has  already  been  stated  it  will  be  seen  how  various  are  the 
different  theories  that  have  been  brought  forward  to  account  for  the  special 
prevalence  of  goitrous  diseases  in  certain  localities,  but  at  the  same  time  it 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  385 

is  noteworthy  that  without  exception  they  all  agree  in  referring  such  ende- 
micity  to  conditions  of  the  soil,  although  at  this  point  agreement  ceases,  so 
that  the  problem  must  be  looked  upon  as  one  which  still  awaits  solution. 
It  appears  certain,  however,  that  whether  or  not  the  presence  of  magnesium 
salts  in  the  soil  in  any  way  predisposes  to  diseases  of  this  kind,  it  is 
extremely  unlikely  that  the  result  is  brought  about  through  the  medium  of 
drinking  water  which  has  been  rendered  hard  by  an  abnormal  quantity  of 
such  salts. 


^  EXAMINATION   OF   SOIL 
Physical  and  Chemical  Examination  of  Soil 

From  one  point  of  view  the  soil  may  be  considered  as  a  mass  of  particles 
of  matter  having  certain  physical  properties  which  will  depend  on  the 
relative  size  of  the  particles  of  which  it  is  composed,  on  the  density  with 
which  they  are  packed  together,  on  their  power  of  absorbing  and  retaining 
water,  and  on  the  friability  of  the  mass. 

Surface  or  subsoil  can  be  mechanically  analysed  either  by  removing  a 
block  of  a  certain  size,  for  instance  a  cube  of  about  six  inches,  or  by  taking 
a  known  weight  (100  grammes),  which  after  being  dried  and  broken  up  by 
the  hands  is  passed  through  a  series  of  sieves.  In  this  way  the  stones  may 
be  separated  according  to  their  various  sizes  by  the  sieves  of  larger  and 
smaller  mesh  until  fine  particles  only  are  left.  These  again  may  be 
separated  still  further  by  mixing  thoroughly  with  water,  and  then  when  the 
coarser  particles  have  subsided,  pouring  off  the  supernatant  fluid  containing 
suspended  matter,  which  consists,  for  the  most  part,  of  silicate  of  aluminium. 
This  part  of  the  process  is  more  accurately  carried  out  by  the  use  of  Noebel's 
apparatus,  which  subdivides  the  finer  matter  into  four  or  more  grades. 

Such  a  mechanical  analysis  is,  however,  of  comparatively  little  importance, 
except  in  so  much  as  it  makes  a  distinction  between  the  silica  which  exists 
as  sand  and  that  which  is  present  as  clay  ;  a  distinction  which  is  not  shown 
in  an  ordinary  chemical  analysis,  in  which  both  kinds  of  silica  would  be 
classed  together.  Should  the  soil  consist  almost  entirely  of  clay,  it  will  dry 
into  a  hard  mass,  which  it  may  be  extremely  difficult  to  break  up  with  the 
hands  alone ;  if,  however,  it  constitutes  what  is  called  loam,  though  still 
drying  into  lumps,  it  will  break  up  more  readily  than  true  clay  owing  to  an 
admixture  of  sand  or  lime.  If  this  latter  substance  be  present  in  considerable 
amount,  the  term  calcareous  will  be  applied  to  the  soil.  The  presence  of 
lime  in  the  soil  is  easily  detected  by  adding  a  few  drops  of  hydrochloric  acid, 
which  by  disengaging  carbonic  acid  gas  from  the  carbonate,  the  form  in 
which  lime  usually  occurs,  causes  effervescence.  The  extent  and  duration 
of  this  give  an  approximate  idea  as  to  the  amount  of  lime  present. 

By  such  a  simple  examination  of  soil  a  considerable  amount  of  information 
may  be  obtained  which  is  of  importance  from  a  hygienic  standpoint,  but 
when  possible  this  should  be  supplemented  by  a  more  extended  chemical 
examination.  The  various  constituents  of  the  soil  may  obviously  be  some- 
what numerous,  but  of  these  a  certain  number  are  extremely  rare,  and  for 
most  purposes  it  suffices  if  a  determination  of  the  following  substances  be 
made— viz.  silica,  alumina,  Mme,  magnesia,  chlorine,  sulphuric  and  nitric 
acids,  carbon  and  nitrogen.  Of  these,  the  two  latter  exist  for  the  most  part 
in  combination  in  the  organic  constituents,  although,  as  has  been  mentioned 
carbonic  acid  is  also  present  m  the  free  state  in  the  interstices  of  the  soil. 

Certain  of  these  constituents  or  compounds  of  them  are  not  soluble  in 

VOL.  1.  CO 


38G  HYGIENE 

water,  although  they  are  capable  of  being  taken  up  by  plants.  Such  is  the 
case,  to  a  considerable  extent,  with  phosphoric  acid  in  the  soil.  The  fact  has 
been  demonstrated  that  when  the  roots  of  plants  come  in  contact  with  a  stone 
slight  indentations  Avill  be  produced  which  have  evidently  been  eaten  away 
during  the  growth  of  the  roots.  This  is  accomplished  by  means  of  the 
extremely  thin  membranes  of  the  root-hair  being  permeated  by  an  acid  juice 
which  coming  in  contact  with  the  surfaces  of  the  particles  of  soil  renders 
soluble  the  molecules  of  nutrient  materials  adhering  there  ;  it  thus  becomes 
possible  for  these  substances  to  penetrate  into  the  root-hairs  according  to  the 
laws  of  diffusion,  and  thence  to  pass  over  into  the  stream  of  sap  to  be  carried 
finally  to  the  organs  of  assimilation.  Sachs  has  shown  experhnentally  that 
roots  which  become  closely  applied  to  the  pohshed  surfaces  of  marble  plates 
corrode  them  so  that  after  a  time  a  corrosion  figure  of  the  roots  is  obtained 
on  the  marble  surface.  Consequently  it  is  usual  in  agricultural  chemistry 
to  estimate  the  composition  of  such  portions  of  the  soil  as  are  soluble  in 
water  and  in  hydrochloric  acid  respectively,  the  former  portion  being  regarded 
as  that  which  is  capable  of  immediate  utilisation  by  plants,  while  the  latter 
insoluble  portion  is  looked  upon  as  a  reserve  fund  which  may  be  utilised  in 
the  future. 

In  order  to  estimate  the  amount  of  organic  matter  in  the  soil  a  known 
quantity  is  weighed  after  careful  drying,  heated  to  redness,  and  then 
reweighed,  the  loss  of  weight  representing  the  organic  matter  which  was 
present.  A  possible  fallacy  must,  however,  be  borne  in  mind  in  conductmg 
this  process,  particularly  when  a  clay  soil  is  being  examined,  seeing  that  in 
such  a  case  a  considerable  amount  of  the  loss  of  weight  which  occurs  on 
heating  will  be  due,  not  to  organic  matter,  but  to  water  of  combination,  which 
is  not  driven  off  unless  the  temperature  be  raised  above  that  of  boiling  water. 

Owing  to  this  fact  the  amount  of  organic  matter  present  in  clay  soils  has 
been  supposed  to  be  as  much  as  from  10  to  12  per  cent.,  which  is  obviously 
erroneous. 

The  portion  which  remains  after  the  organic  constituents  have  been 
dissipated  by  the  effect  of  heat  consists  of  the  inorganic  or  mineral  consti- 
tuents. 

The  substances  soluble  in  water  consist  for  the  most  part  of  chlorides, 
sulphates,  and  nitrates,  while  the  greater  part  of  the  magnesia,  lime,  alumina, 
and  iron  are  insoluble.  It  is  important  to  determine  the  extent  to  which  the 
constituents  of  a  given  soil  are  thus  soluble,  so  as  to  obtain  an  indication  as  to 
whether  drinking  water  obtained  from  such  a  soil  is  liable  to  be  injuriously 
affected.  For  this  purpose  10  grammes  are  to  be  thoroughly  shaken  with 
distilled  water.  Filter  ;  evaporate  the  filtrate,  weigh,  and  incinerate.  The 
loss  of  weight  after  incineration  will  indicate  organic  matter,  together  with 
varying  amounts  of  water  of  combination  and  of  ammonia  ;  Way  having 
shown  that  the  absorbent  property  of  clay  particularly  enables  a  soil  to  retain 
such  an  amount  of  ammonia  in  the  soil  as  to  exert  a  very  important  purify- 
ing influence  upon  water  impregnated  with  organic  and  other  substances, 
which  find  their  way  slowly  through  the  soil.  Dissolve  the  residue  again 
in  water  and  examine  for  chlorine,  sulphuric  acid,  lime,  alumina,  iron,  and 
nitric  acid.  (A  description  of  the  necessary  methods  will  be  found  in  the 
section  on  Wateb.) 

To  the  portion  insoluble  in  water  add  pure  hydrochloric  acid  after  pre- 
vious evaporation.  Or,  more  accurately,  (1)  take  40  grammes  of  a  fresh 
portion  of  the  soil  and  to  it  add  30  c.c.  of  hydrochloric  acid  and  heat,  noting 
whether  effervescence  takes  place.  Add  100  c.c.  of  distilled  water  and 
digest  for  about  twelve  hours.     Filter ;  dry  and  weigh  the  residue. 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  387 

(2)  To  the  acid  solution  add  ammonia,  which  will  precipitate  oxide  of  iron 
and  alumina.     Filter  ;  dry  and  weigh  the  precipitate. 

(3)  To  the  filtrate  add  ammonium  oxalate.  Filter ;  dry  ;  wash  and  burn 
the  calcium  oxalate  and  weigh  the  calcium  carbonate  produced. 

(4)  To  the  filtrate  from  (3)  add  sodium  phosphate.  Collect  the  precipitate  ; 
dry  and  weigh.  Every  100  parts  represents  seventy-nine  parts  of  magnesium 
carbonate. 

(5)  The  residue  remaining  after  treatment  with  hydrochloric  acid  consists 
of  clay,  quartz,  and  silicates  of  aluminium,  iron  calcium,  and  magnesium. 
Fuse  with  three  times  its  weight  of  sodium  carbonate  and  then  heat  with 
dilute  hydrochloric  acid.  Iron,  lime,  alumina,  and  magnesia  will  enter  into 
solution,  silica  remaining  undissolved.  Filter ;  dry  and  weigh  the  insoluble 
residue. 

(6)  Evaporate  the  filtrate  from  (5)  to  dryness.  Moisten  the  residue  with 
a  concentrated  solution  of  ammonium  nitrate  and  heat  on  the  water-bath 
until  the  evolution  of  ammonia  ceases.  Add  hot  water,  filter,  wash  the 
alumina  and  ferric  oxide  ;  dry,  ignite  and  weigh.  ^  The  mixed  oxides  should 
now  be  heated  in  a  porcelain  boat  for  about  half  an  hour,  while  a  stream  of 
dry  hydrogen  or  coal  gas  is  passed  over  them.  To  the  mixture  of  alumina 
and  reduced  iron  add  a  2^  per  cent,  solution  of  nitric  acid  in  distilled  water  ; 
warm,  filter,  precipitate  the  ferric  oxide  by  ammonia,  wash,  dry  and  weigh  it. 
By  deducting  the  weight  of  ferric  oxide  from  that  of  the  mixed  oxides  the 
quantity  of  alumina  is  obtained. 

The  iron  may  also  be  estimated  by  heating  the  mixture  of  alumina  and 
ferric  oxide  with  dilute  sulphuric  acid,  filtering,  reducing  with  a  small  piece 
of  zinc,  and  titrating  with  a  standard  solution  of  potassium  permanganate. 

This  method  of  estimating  Fe  depends  on  the  fact  that  KMn04,  added 
to  a  solution  of  a  ferrous  salt,  oxidises  it  to  the  ferric  state. 

The  reaction  is  : 

10FeS04-f  2KMn04  +  8H2SO4  =  5Fe2(S04)3  4-  K2SO4  -f  2MnS04  -f  8H2O 

The  ferrous  solution,  prepared  as  above  directed,  is  made  up  to  bulk 
with  cold  distilled  water  in  a  250  c.c.  flask,  and  50  c.c.  of  this  solution  are 
transferred  to  a  beaker  containing  200  c.c.  of  air-free  water  standing  on 
a  sheet  of  white  paper.  Now  run  in  the  standard  permanganate  from  a 
Mohr's  burette,  provided  with  a  glass  stopper,  little  by  little,  and  with  constant 
stirring :  as  the  KMn04  falls  into  the  solution  of  ferrous  salt  a  pink  blush 
is  formed,  but  disappears  on  stirring  as  long  as  there  is  any  ferrous  salt  un- 
oxidised  to  ferric.  As  soon  as  all  is  converted  into  ferric,  the  pink  coloura- 
tion is  permanent,  and  this  is  the  end  of  the  reaction.  Eead  off  the  number 
of  c.c.  needed  to  effect  this,  and  repeat  with  two  more  successive  quantities  of 
50  c.c.  of  the  ferrous  solution,  and  take  the  mean  of  the  three  results  as  a 
basis  for  calculation.  The  permanganate  solution  requires  standardising 
from  time  to  time  ;  the  method  of  doing  this  and  the  preparation  and 
standardisation  of  the  permanganate  solution  in  the  first  instance  are  well 
given  in  Thorpe's  '  Quantitative  Analysis,'  p.  148. 

Calculation : 

Let  X  =  number  of  c.c.  KMn04  used, 

y  =  weight  of  Fe  in  grammes  oxidised  by  1  c.c.  KMn04 ; 

•  •  -^y  ^    >)  J)  »>  V  ^         >j 

i.e.  xy  =      „  ,,  in  grammes  in  50  c.c.  solution  ; 

/.  5xy=  Fe  in  250  c.c.  or  in  mixture  of  Fe  and  Al  from  (6). 

1  For  the  total  aluminium  and  iron  the  results  of  (2)  should  be  added  to  the  residue 
thus  obtained. 

c  c  2 


)88 


HYGIENE 


Appended  are  some  complete  analyses  of  surface  soils  which  give  a  fair 
idea  of  the  mamieriu  which  they  ditier  from  one  another  iu  composition  : — 

Complete  Analyses  of  Soils  (Lloyd) 


No.V.    18 

— 

No.  I. 

No.IL 

No.  in. 

No.  IV. 

No.  V. 

to  27  in. 
deep 

♦Organic  matter    and    water 

1 

of  combination  . 

5^033 

6^844 

4^200 

8^858 

3-450 

1-550 

Oxide  of  iron 

5-200 

5-312 

3-659 

6-350 

4-001 

3-201 

Alumina       .... 

3-400 

4-560 

4-100 

8-430 

•649 

•449 

Lime     ..... 

1-360 

3-312 

•670 

•484 

•431 

•151 

Magnesia      .... 

•400 

•432 

•266 

•466 

•225 

-201 

Potassium  oxide   . 

•3G5 

•468 

•320 

•333 

•282 

•253 

Sodium  oxide 

•r2i 

•179 

•031 

•092 

•069 

•023 

Phosphoric  acid    . 

•141 

•204 

•141 

•217 

•217 

•141 

Carbonic  acid 

•875 

1-640 

•380 

— 

— 

— 

Sulphuric  acid 

•060 

•109 

•061 

•137 

•130 

•089 

Nitric  acid    .        .        .        • 

•001 

•001 

•001 

•002 

•008 

•002 

Chlorine        .... 

•005 

•Oil 

-002 

•005 

•007 

-004 

flnsoluble  silicates  and  sand 

88^066 

77-401 

86-232 

79-733 

90^675 

93-925 

100-027 

99-973 

100-063 

100-107 

100^144 

99-989 

f  Consisting  of  oxide  of  iron   . 

1-827 

1-625 

•763 

1-594 

I  1-995 

2-723 

Alumina    .... 

6-188 

4-489 

6-607 

1^897 

Lime          .... 

•511 

•774 

•638 

•558 

•553 

•732 

Magnesia  .... 

•388 

•332 

•167 

•223 

•126 

•181 

Potash      .... 

•424 

•578 

•182 

•358 

•399 

•197 

Soda 

•920 

•534 

•304 

1-012 

1^242 

•779 

Silica         .        .        .        . 

72^848 

69-273 

77-626 

74-091 

86-360 

89-363 

83^106 

77-545 

86-287 

79-738 

90-675 

93-925 

^Containing  nitrogen 

•170 

•107 

•141 

•254 

•101 

•050 

In  the  first  three  specimens  of  soil  which  were  analysed  by  Dr.  Voelcker 
there  was  a  considerable  amount  of  clay,  they  being  what  are  termed  '  stiff ' 
soils,  while  No.  IV.  is  a  loamy  soil  from  Bedfordshire,  and  No.  V.  a  light 
sandy  or  gravelly  soil.  The  sixth  table  shows  an  analysis  of  the  subsoil 
lying  beneath  No.  V.,  and  it  is  obvious  that  it  contains  far  less  soluble  con- 
stituents than  the  surface  layer  above. 


Bacteeiological  Examination  of  Soil 

The  number  of  bacteria  which  may  be  found  in  mould  or  surface  soil  is 
usually  very  large,  although  pathogenic  organisms  are  comparatively  rare, 
except  perhaps  in  the  filth-laden  soil  of  crowded  and  insanitary  districts. 
Certain  forms,  indeed,  are  distinctly  beneficial,  since  by  their  hfe  processes 
oxidation  (nitrification)  of  nitrogenous  organic  matters  in  the  soil  is  brought 
about,  while  other  forms,  as  agents  of  putrefaction  and  fermentation,  play  a 
very  important  part  in  the  economy  of  nature. 

It  will  be  obvious,  therefore,  that  the  mere  presence  of  even  considerable ' 
numbers  of  micro-organisms  in  a  sample  of  earth  does  not  of  necessity  show 
that  there  is  danger  to  health  in  building  on  or  even  in  obtaining  water  from 
the  locality  from  which  it  is  taken,  and  therefore  the  mere  enumeration  of 
the  number  of  colonies  which  can  be  grown  on  a  nutrient  medium  from  a 
given  weight  of  earth  is  a  very  fallacious  test. 

In  addition,  the  various  colonies  must  be  isolated  and  sown  on  media  of 
various  kinds,  and  methods  of  staining,  and  even  of  experimental  inoculation, 


THE  INFLUENCE   OF  SOIL   ON  HEALTH  389 

would  require  to  be  carried  out  before  it  can  be  definitely  asserted  that  any- 
thing of  a  pathogenic  nature  is  present  or  not.  It  is,  of  course,  impossible 
that  such  an  examination  can  in  every  case  be  carried  out  in  its  entirety,  and 
therefore  we  are  thrown  back  on  the  use  of  the  ordinary  microzyme  test,  the 
only  use  of  which  is  in  enabling  us  to  judge  of  the  approximate  number  of 
micro-organisms  present,  and  not  in  forming  an  opinion  as  to  whether  the 
soil  is  of  such  a  nature  as  would  be  likely  to  harbour  organisms  of  a  dangerous 
nature. 

For  the  purpose  of  obtaining  a  cultivation  of  the  micro-organisms  in  soil 
there  are  various  modes  of  procedure.  Either  the  ground  air  aspirated  from 
diiierent  depths  (as  in  the  method  used  by  Lewis  and  Cunningham  for  the 
estimation  of  the  carbonic  acid)  may  be  drawn  over  the  surface  of  nutrient 
gelatine,  or  samples  of  the  soil  itself  may  be  examined.  This,  which  is  the 
simpler  method,  is  carried  out  as  follows  : — 

A  sample  of  earth  is  first  dried,  then  finely  powdered  and  shaken  up  in  a 
test  tube  of  sterilised  water,  a  drop  of  this  being  afterwards  transferred  to 
another  tube  of  peptone-broth  or  gelatine.  Again  a  small  quantity  of  the 
earth  may  be  sprinkled  directly  over  the  surface  of  nutrient  gelatine  prepared 
for  a  plate  cultivation.  The  best  method  of  all,  however,  probably  consists 
in  taking  a  carefully  weighed  amount  of  dried  and  pulverised  earth  and 
adding  it  to  a  test  tube  of  gelatine,  which  has  been  previously  rendered  fluid 
by  heat.  By  shaking  it  is  distributed  as  evenly  as  possible  through  the 
medium,  which  is  then  poured  out  over  the  surface  of  a  carefully  levelled 
glass  plate,  on  which  it  gradually  sets  into  a  solid  film.  If  the  plate  has 
been  previously  divided  up  into  squares  by  carefully  ruled  lines  cut  on  the 
luider  surface  of  the  glass,  it  is  very  easy  to  count  the  number  of  colonies 
which  develop  in  a  given  area,  and  so  by  counting  the  squares  to  calculate 
the  number  of  bacteria  that  were  originally  present  in  the  given  sample  of  earth. 
These  colonies  become  noticeable  after  a  few  days'  growth,  when  the  various 
species,  owing  to  the  difference  in  their  mode  of  growth,  will  form  clusters 
varying  in  size,  aspect,  and  arrangement.  As  Klein  has  shown,  however, 
it  must  be  borne  in  mind  that  the  number  of  colonies  is  no  absolute  index  of 
the  number  of  bacteria  in  the  soil  for  the  following  reasons  :  (a)  not  every 
colony  that  makes  its  appearance  on  the  plate  cultivation — even  granted  that 
it  is  due  to  the  growth  of  a  single  species,  which  is  not  invariably  the  case — 
owes  its  origin  to  one  single  individual,  since,  for  instance,  micrococci, 
bacteria,  and  bacilli  may  occur  in  the  original  sample  as  zooglea  and  chains, 
and  these  cannot  by  any  amount  of  shaking  be  broken  up  into  single 
elements ;  {h)  not  all  bacteria  introduced  into  the  gelatine  come  up  as  colonies, 
since  not  all  of  them  are  capable  of  growing  in  the  gelatine,  and  not  ah.  of 
them  can  thrive  at  the  temperature  at  which  the  gelatine  remains  solid  ;  (c) 
the  liquefaction  of  the  gelatine  by  some  of  the  colonies  and  not  by  others  does 
not  necessarily  indicate  different  species,  since  this  depends  sometimes  on 
the  nature  of  the  nutrient  gelatine,  and  to  the  fact  whether  the  growth  takes 
place  in  the  depth  or  on  the  surface ;  [d)  accidental  contamination  with 
organisms  of  the  air  during  the  preparation  of  the  plate  cultivation  cannot 
be  prevented,  and  if  the  air  happens  to  contain  a  good  many  organisms, 
as  would  be  likely  to  be  the  case  in  an  ordinary  laboratory,  for  instance, 
the  total  number  of  colonies  appearing  in  the  plate  cultivation  may 
exceed  the  number  of  bacteria  present  in  the  sample  of  earth  which  was 
being  tested. 

There  are  certain  pathogenic  organisms  which  have  so  typical  a  mode  of 
growth,  as  is  the  case  with  the  anthrax  bacillus,  which  has  been  proved  by 
Pasteur  to  be  capable  of  existing  in  the  soil,  that  their  presence  or  absence 


390  HYGIENE 

may  be  detected  by  simple  examination  of  the  cultivation,  but,  as  stated 
above,  this  -svill  usually  not  be  the  case. 

In  a  similar  manner  to  that  already  described,  the  dust  which  settles  from 
the  air  in  houses  and  hospitals  or  other  pubhc  buildings  may  be  distributed 
over  the  surface  or  in  the  substance  of  nutrient  gelatine,  and  thus  the  micro- 
organisms which  develop  may  be  studied  both  as  regards  their  morphological 
and  biological  characteristics. 


FOOD 


BY 


SIDNEY   MARTIN,  M.D.,  F.R.C.P. 

ASSISTANT  PHYSICIAN  TO  UNIVERSITY  COLLEGE  HOSPITAL 


FOOD 

By  food  we  mean  the  substances  taken  into  the  body  which  are  utilised  in 
maintaining  the  functional  activity  of  the  organism.  By  means  of  food 
during  adolescence,  growth  is  maintained,  and  in  adult  life  the  body-weight 
remains  at  a  healthy  level,  or  increases  in  particular  conditions,  the  tem- 
perature is  maintained,  and  muscular  effort  is  made  possible.  The  importance 
of  the  scientific  study  of  food  and  of  dietetics  from  a  hygienic  standpoint 
cannot  therefore  be  overestimated.  The  definition  just  given  would  neces- 
sarily include  under  the  heading  Food  the  oxygen  taken  into  the  body  by 
means  of  the  lungs  ;  and,  strictly  speaking,  oxygen  is  a  food,  and  one  of 
the  most  important.  The  taking  in  of  oxygen  is,  however,  unlike  that  of 
food,  in  the  main  an  involuntary  act ;  so  that  the  term  'food'  is  limited 
to  substances  taken  by  the  mouth  into  the  digestive  tract,  where,  for  the 
most  part,  they  undergo  changes  preparatory  to  entering  the  tissues  of  the 
organism — preparatory  to  assimilation,  as  the  process  is  termed. 

The  Proximate  Pbinciples  op  Food,  ok  Foodstuffs 

are  the  substances  which  constitute  food.  They  may  be  classified  as 
follows  : — 

[1.  Nitrogenous,  as  proteids  or  albuminoids. 
I.  Organic      \  i{a)  Fats. 

(2.  Non-nitrogenous  \{h)  Carbohydrates. 
[(c)  Vegetable  acids. 
II.  Inorganic   (1-  Mineral  salts. 


.2.  Water. 
III.  Food- accessories,  such  as  tea,  coffee,  alcohol,  creatin,  &e. 

The  first  two  classes  of  foodstuffs  are  essential  to  life  ;  but  in  the  food 
of  man  there  is  a  third  class  of  what  may  be  called  '  food-accessories,' 
which  hold  an  important  position  in  dietetics.  They  are  flavouring 
agents,  stimulants,  &c.,  and  are  well  expressed  by  their  German  name, 
*  Genussmittel.' 

Nitrogenous  Foodstuffs 

The  greater  part  of  the  solid  constituents  of  the  tissues  of  the  body  (with 
the  exception  of  bone)  consists  of  abuminous  or  proteid  substances  ;  the 
liquids  of  the  body  also  contain  them  in  solution,  not  only  the  blood  and  the 
lymph,  but  also  the  interstitial  liquid  of  the  tissues,  which  is  really  a  form  of 
lymph.  A  certain  amount  of  nitrogen  in  the  form  of  urea  (30  to  iO 
grammes  or  500  grains  daily),  and  of  uric  acid  (0-5  gramme  or  7  to  10 
grains  daily),  with  a  few  other  nitrogenous  bodies  in  small  amount,  is  daily 
excreted  in  the  urine.  These  nitrogenous  bodies  are  formed  fi-om  the 
destruction  (oxidation)  of  the  proteids  of  the  body  ;  the  nitrogen  they  contain 
is  a  loss  to  the  body,  and  to  repair  this  loss  a  daily  intake  of  nitrogenous 
food  is  necessary.     By  this  means  the  nitrogen-equilibrium  of  the  body  is 


394  HYGIENE 

maintained — that  is,  the  relation  between  the  intake  and  output  of  nitrogen. 
The  equihbrium  is,  however,  not  perfect,  since  the  sum  of  the  nitrogen 
passed  in  the  urine  and  fa?ces  is  less  than  that  taken  into  the  system.  The 
only  form  of  nitrogen  which  the  body  can  assimilate  is  that  of  proteid  or 
albuminous  substances.  The  plant  builds  up  its  proteids  from  the  nitrates 
and  ammonia  of  the  soil,  but  the  animal  cannot  do  this  :  it  utilises  the 
proteids  originally  synthetised  by  the  plant. 

Proteids  are  composed  of  carbon,  hydrogen,  nitrogen,  and  oxygen ;  they 
all  contain  sulphur,  and  some  contain  phosphorus.  Their  chemical  con- 
stitution (and  so  their  molecular  weight)  is  unlmown ;  but  although  there 
are  individual  differences  of  composition,  especially  between  animal  and 
vegetable  proteids,  their  average  percentage  composition  may  be  stated  as 
follows  (Hoppe-Seyler) : — 

0  H  N  C  S 

From       .        .     20-9  6-9  15-2  51-5  0-3 

To  .         .        .     23-5  7-3  17-0  54-5  20 

Thus  more  than  half  of  a  given  weight  of  proteid  bodies  is  composed  of 
carbon,  while  they  contain  about  16  per  cent,  of  nitrogen.  The  proteids 
taken  in  as  food  are  derived  both  from  animals  and  plants  ;  and,  as  far  as 
is  at  present  known,  there  is  no  difference  in  nutritive  value  between  the 
proteids  from  these  two  sources.  Considered  as  food,  they  may  be  divided 
into  two  groups  :  one,  true  proteids,  the  members  of  which  are  of  equal 
nutritive  value,  and  are  capable  of  sustaining  the  N-equilibrium  of  the 
body  ;  the  other,  albuminoids,  which  are  not  equal  in  nutritive  value  to  the 
first  group,  and  are  not  capable  of  performing  completely  the  functions  of 
proteid  food. 

This  second  group  contains  substances  obtained  only  from  animals — such 
as  gelatin  [ossein^),  cliondrin,  and  keratin.  Gelatin,  the  only  important  member 
of  this  group,  contains  a  larger  percentage  of  nitrogen  than  the  ordinary 
proteids — viz.  from  17'8  to  18'8  per  cent. ;  it  differs  also  in  some  chemical 
reactions,  and  does  not,  like  most  proteids,  yield  tyrosin  on  decomposition. 

The  first  group  of  proteid  foods  are  the  most  important ;  they  may  be 
divided  into — 

1.  Globulins. — The  myosin  of  muscle,  the  globulin  of  the  serum  of  the 
blood,  those  contained  in  the  white  and  yolk  of  eggs,  are  examples  from  the 
animal  kingdom,  while  from  the  vegetable  kingdom  are  the  globulins  con- 
tained in  the  seeds  of  Leguminosse  and  of  the  cereals. 

2.  Albumins. — The  albumin  of  the  serum,  and  egg-albumin. 

3.  Insoluble  Proteids.'^ — The  fibrin  of  the  blood  and  the  gluten  of  wheat. 
These  three  classes  have  one  common  characteristic,  they  are  coagulated 

by  heat ;  when  coagulated,  as  in  the  process  of  cooking,  they  are  insoluble 
in  water  and  dilute  acids  or  alkalies,  but  are  readily  digested  and  rendered 
soluble  by  the  gastric  and  pancreatic  juices  (pepsin  or  trypsin). 

4.  Albumoses. — These  are  closely  related  to  peptones,  and  are  foimd  in 
the  cereals,  and  are  taken  as  food  in  wheaten  flour,  rye,  rice,  and  barley. 
They  are  probably  widely  distributed  in  the  vegetable  kingdom,  and  are 
formed  by  pepsin  from  the  ordinary  proteids  of  foods  (Classes  1  to  3). 
These  animal  albumoses  are  often  administered  in  partially  digested  foods  to 
invalids :  they  are  the  precursors  oi  peptones,  which  also  belong  to  this  class 
of  proteids. 

5.  A  fifth  class  of  food-proteids  includes  the  casein  of  milk,  and  tbe  legu* 

•  There  is  practically  no  difference  between  ossein  and  gelatin  (Schiitzenberger). 
'  That  is,  those  insoluble  in  water  and  in  saline  solutions  at  ordinary  temperatures. 


FOOD  895 

min  ^  and  conglutin  of  peas,  beans,  &c,  (Leguminosse).  Classes  4  and  5  have 
the  common  characteristic  of  not  being  precipitated,  and  thus  not  coagu- 
lated, by  boiling  their  solutions.  The  albumoses  and  peptones  do  not  require 
so  complete  a  digestion  as  the  casein  of  milk. 

As  an  appendix  to  Class  5  may  be  mentioned  syntonin  or  acid  albumin, 
which  exists  in  some  foods  (e.g.  meat)  and  alkali  albumin  :  these  are  formed 
by  the  action  of  dilute  acids  and  alkalies  on  ordinary  proteids,  and  are  not 
precipitated  from  solution  by  boiling. 

Non-nit7'ogenous  Organic  Foodstuffs 

These  are  fats  and  carbohydrates. 

Fats. — In  the  majority  of  diets  used  by  different  nations,  fat  is  an  added 
constituent.  It  is  absorbed  by  the  body  chiefly  in  the  form  of  neutral  fat, 
but  also  in  the  form  of  fatty  acids  and  of  their  compounds,  alkaline  soaps. 
The  neutral  fat  taken  as  food  always  contains  free  fatty  acids  in  greater  or 
less  proportion,  and  in  some  foods  {e.g.  cheese)  the  fatty  acids  are  in  large 
proportion. 

Fats  are  compounds  of  the  triatomic  alcohol  glycerine,  C3H5  (0H)3,  and 
fatty  acids.  These  fatty  acids  belong  to  two  series  :  1,  monobasic  acids,  of 
the  general  formula  CnH2i,._iO(OH),  such  as  palmitic  acid,  C16H32O2,  and 
stearic  acid,  C18H36O2.  The  fats  formed  are  called  palmitin  and  stearin, 
both  solid  compounds.  2.  x\cids  of  the  acrylic  acid  series,  with  the  general 
formula  CnH2n-30(OH),  such  as  oleic  acid,  C18H34O2.  Olein  is  a  liquid 
fat. 

All  fats  contain  carbon,  hydrogen,  and  oxygen,  and  differ  from  carbo- 
hydrates in  the  fact  that  the  oxygen  is  proportionately  less  than  will  form 
water  (HgO)  with  the  hydrogen  contained  in  the  molecule.  In  food  there  is 
a  mixture  of  neutral  fats  with  free  fatty  acids  ;  the  solid  fats  are  generally 
mixed  with  olein.  (For  fats  present  in  different  foods,  see  separate  accounts 
of  articles  of  diet.) 

Carbohydrates  are  derived  chiefly  from  vegetable  foods,  and  are  mostly 
taken  as  food  in  the  form  of  starch.  They  all  contain  carbon,  hydrogen,  and 
oxygen,  the  hydrogen  and  oxygen  being  in  the  proportion  to  form  water. 

1.  The  group  of  glucoses  (C6Hi206)n  consists  of  three  forms;  (a)  grape- 
sugar  (dextrose,  glucose),  {b)  galactose,  a  product  of  milk-sugar,  and  (c) 
IcBVulose  (invert-sugar),  which  is  contained  in  the  juices  of  plants  and  in 
honey ;  {d)  inosite,  isomeric  with  grape-sugar,  and  found  in  muscle  and 
some  other  animal  foods,  and  in  beans  and  the  juice  of  the  grape. 

2.  A  second  group  differs  from  the  first  group  in  containing  one  molecule 
of  water  less  than  the  double  molecule  of  glucose;  thus  2(C6Hi206)— HjQ 
=  C12H22O11.  To  this  group  belong  {a)  milk-sugar  or  lactose,  occurring  in 
milk  ;  (&)  maltose,  which  is  the  end-product  of  the  digestion  of  starch  in  the 
digestive  tract ;  (c)  saccharose  or  cane-sugar,  occurring  in  many  plants,  as 
the  sugar-cane  and  the  beet. 

3.  A  third  group  contains  bodies  with  the  formula  (CeHjoOg)!!,  and  are 
related  to  members  of  the  second  group  by  considering  them  as  containing 
one  molecule  less  of  water.  Thus  milk-sugar,  C12H22O11  —  H2O  =  starch, 
2(C6Hio0.5).  To  this  group  belong  [a)  glycogen  ('  animal  starch  '),  found  in 
certain  articles  of  diet,  such  as  liver  and  molluscs  ;  {b  )  dextrine,  associated 
with  starch  in  many  foods  and  formed  from  starch  m  the  digestive  tract ; 

'  It  is  probable  that  legumin  and  conglutin  are  not  really  '  vegetable  caseins,'  but  are 
artificial  products,  the  alkali  used  in  their  extraction  transforming  the  globulin  present 
(Vines).     The  proteids  of  vegetable  foods  require  complete  reinvestigation. 


396  HYGIENE 

(c)  amylum  or  starch,  found  in  vegetable  cells ;  {d)  cellulose.  This  last, 
although  of  no  great  value  as  food  to  man,  is  of  value  to  herbivorous  animals. 
The  presence,  however,  of  indigestible  cellulose  in  the  food  of  man  has  an 
effect,  as  will  be  pointed  out,  on  the  complete  digestion  and  absorption  of 
digestible  foods. 

Vegetable  Acids 

These  are  grouped  together,  although  they  belong  to  different  chemical 
groups,  because  they  perform  the  same  physiological  function  :  their  salts 
are  converted  into  carbonates  in  the  body,  and  thus  preserve  the  alkalinity  of 
the  blood,  tissues,  and  secretions  (e.g.  pancreatic  juice). 

Acetic  acid,  C2H.,02,  and  lactic  acid  (oxypropionic  acid),  CgHi^Oa,  belong 
to  this  group  :  they  are  related  to  fatty  acids,  but  in  their  function  as  food 
differ  greatly  from  fatty  acids. 

The  other  acids  belonging  to  this  group  are  also  allied  to  the  fatty 
acid  series  :  oxalic  acid,  H0C2O4 ;  tartaric  acid,  C4HQO6  (dioxysuccinic  acid) ; 
citric  acid,  CqH.^O'j  ;  malic  acid,  CiHgO^  (oxysuccinic  acid).  This  group 
differs  from  the  first  in  the  fact  that  they  have  an  excess  of  oxygen  in  their 
composition — more  0  than  will  form  water  with  the  H  they  contain. 

The  most  important  of  these  vegetable  acids  are  tartaric  and  citric  acids. 

Inorganic  Foodstuffs 

The  salts  taken  in  as  food  which  are  of  importance  to  the  organism  are 
sodium  chloride,  potassium  chloride,  the  phosphates  of  calcium  and  mag- 
nesium, and  iron  compounds.  Sulphates  are  of  minor  importance.  The 
carbonates  of  sodium  (NagCOg  and  NaHCOg)  are  of  great  importance  in  the 
organism :  they  are,  however,  chiefly  derived  from  the  vegetable  acids  taken 
with  the  food  (see  p.  lOO.) 


The  Change  of  Foodstuffs  in  the  Body — theik  Nutkitive 

Functions 

Nitrogenous  foodstuffs  are  necessary  to  animal  life  :  they  are  the  only  form 
in  which  nitrogen  can  be  assimilated  by  the  organism  so  as  to  act  as  nutri- 
ment to  the  tissues.  When  taken  into  the  digestive  tract,  both  animal  and 
vegetable  proteids  (Classes  1-3)  become  transformed  by  the  pepsin-hydro- 
chloric acid  of  the  gastric  juice  into  syntonin,  albumoses,  and  peptones ; 
by  the  trypsin  of  the  pancreatic  juice  into  peptones  and  an  intermediate 
body,  while  part  of  the  peptone  is  further  split  up  into  two  nitrogenous 
bodies,  leucin  and  tyrosin.  These  crystalline  bodies  cannot  replace  proteids 
in  a  diet.  They  are  amido-acids,  and  like  other  bodies  of  their  class,  except 
asparagin,  they  cause  a  decomposition  of  proteid  in  the  body  if  they  are 
given  in  the  food  as  part  of  the  proteid.^ 

Gelatine  is  also  transformed  into  albumoses  in  the  stomach  and  small 
intestine ;  keratin  is  not  digested  in  the  stomach  but  only  by  the  pancreatic 
juice  in  the  small  intestine.  The  digested  products  of  these  bodies  differ  in 
chemical  reactions  from  those  of  Classes  1-3.  The  difference  of  nutritive 
value  is  greater  than  that  of  their  chemical  reactions. 

Some  of  the  native  proteids  taken  in  as  food  may  be  absorbed  as  such 
(Briicke),  but  most  physiologists  are  agreed  that  proteids  are  absorbed  from 

'  See  P.  BaUmann,  Inaug.  Dissert.  Miinster,  1885.  Quoted  by  Konig,  Nahrungs- 
mittellehre,  Bd.  i.  p.  121,  3rd  edit. 


FOOD  307 

the  digestive  tract  in  the  form  of  albumoscs  and  peptones,  and,  according  to 
the  researches  of  Hofmeister,^  von  Ott,^  Popoff,^  and  Brinck,  they  are 
transformed  by  the  mucous  membrane  of  the  stomach  and  intestine  into 
serum-albumin.  Albumoses  and  peptones  thus  form  an  important  constituent 
of  the  artificial  foods  for  invalids  ;  they  do  not,  however,  possess  the  same 
nutritive  value  as  the  ordinary  proteids  of  food.  The  well-known  experi- 
ments of  Plosz  and  Maly  tend  to  show  that  they  are  equal  in  nutritive 
value  to  albumin  and  other  proteids  :  they  fed  a  dog,  for  example,  on  pep- 
tone, fat,  and  carbohydrate  for  a  period  of  eighteen  days,  and  found  that  at  the 
end  of  that  time  it  had  gained  considerably  in  weight.  According  to  Voit, 
however,  rats  in  whose  diet  peptones  are  substituted  for  the  ordinary  pro- 
teids of  food  succumb  after  a  period  of  seven  months.  It  is  possible  that 
when  a  large  quantity  of  peptone  is  given,  much  of  it  is  split  up  by  the 
pancreatic  juice  into  leucin  and  tyrosin,  and  is  thus  lost  as  food  to  the 
organism. 

We  may  take  the  fact  as  certain  that  the  nitrogenous  foods  absorbed 
from  the  digestive  tract  become,  sooner  or  later,  transformed  into  one  of 
the  proteids  of  blood ;  they  can  in  this  form  be  utilised  by  the  tissues.  We 
know  also  that  the  end-products  of  the  changes  they  undergo  in  the  body 
are  nitrogenous  excretive  matters,  urea  and  uric  acid.  Some  considerations  in 
relation  to  the  metabolism  of  proteids  in  the  body  are,  therefore,  of  extreme 
importance  from  a  dietetic  point  of  view :  these  will  now  be  reviewed.  The 
cells  which  compose  the  animal  body  are  formed  of 'protoplasm,'  whether 
metamorphosed  into  the  nerve-cell,  the  muscle-fibre,  or  the  chief  structures 
of  other  tissues.  Prom  one  point  of  view  protoplasm  may  be  considered 
as  '  living  '  proteid,  since  after  its  death  the  greater  part  of  it  consists  of  the 
proteids  or  nitrogenous  substances  which  are  taken  in  as  food.  Two  con- 
siderations are  of  importance  with  regard  to  the  life  of  the  cellular  elements 
of  the  body.  (1)  In  order  that  they  may  continue  to  exist,  they  must  be 
supplied  with  nitrogenous  food  in  the  form  of  proteids.  (2)  By  their  means 
the  physiological  processes  of  the  animal  body  are  carried  on.  When  the  body 
is  deprived  of  nitrogenous  food,  the  tissues  do  not  at  once  cease  their  activity, 
for  they  have  a  store  of  nitrogenous  food  on  which  they  can  draw.  This 
store  exists  partly  in  the  blood,  the  so-called  '  circulating  proteid,'  and  partly 
in  the  tissues  themselves :  when  this  is  exhausted,  the  tissues  then  begin 
to  waste  from  the  insufficiency  of  nitrogenous  food. 

Practically  speaking,  the  nutrition  of  the  nitrogenous  tissues  means  the 
nutrition  of  the  body.  Thus  the  physiological  activity  of  glands,  of  muscles, 
of  the  nerve-cells,  of  the  connective-tissues,  of  the  spermatozoa,  and  of  the 
ovum  depends  on  the  food  supplied  to  and  assimilated  by  them.  As  regards 
glands,  their  secretion  is,  in  the  case  of  the  digestive  glands,  rich  in  proteid 
substances  which  are  closely  associated  with  the  active  agents  of  the  secretion, 
the  ferments.  In  the  connective  tissue,  also,  the  fat  is  stored  up  by  means 
of  the  cells  it  contains  ;  it  is  not  simply  located  in  the  tissues  ;  its  storing  up 
is  due  to  the  assimilating  activity  of  the  cell,  developed  in  one  particular 
direction,  viz.  that  of  taking  in  fat.  The  liver-cells,  moreover,  take  up  most 
of  the  carbohydrates  digested  in  the  intestine,  and  this  assimilation  is  due 
to  the  activity  of  the  living  nitrogenous  cell.  Therefore  all  the  physiological 
processes  of  the  body  occur  by  means  of  its  nitrogenous  cell-elements,  and 
the  food  we  eat  to  nourish  the  tissues  of  the  body  must  be  taken  up  by  the 

'  Arch.  f.  exper.  Path.  Bde.  xix.  and  xs.     1885. 
*  Dubois-Eeymond's  Archiv.     1883. 
»  Zeits.f.  Biologic.    1889. 


898  HYGIENE 

cell-elements  before  it  produces  its  effect.  The  process  of  oxidation  is  also 
closely  associated  \\dtb  the  activity  of  the  cell-elements  of  the  tissue,  so  that, 
as  Pettenkofer  and  Voit  have  shown,  '  the  nitrogenous  substances  composing 
the  textures  of  the  body  determine  the  absorption  of  oxygen,'  and  it  is  not 
that  the  '  absorption  of  oxygen  determines  the  changes  in  the  tissues ; ' 
oxidation  in  the  body,  moreover,  is  not  proportional  to  the  amount  of  oxygen 
inspired,  as  Lavoisier  and  Liebig  thought,  but  to  the  necessity  of  the  tissues 
for  oxygen. 

The  proper  and  regulated  supply  of  nitrogenous  food  to  the  organism  is, 
as  is  evident  from  what  has  just  been  said,  of  prime  importance.  But  in  the 
matter  of  food,  it  is  difficult,  if  not  impossible,  to  point  out  that  one  food- 
stuff is  more  important  than  another,  difficult  where  a  deficiency  of  any  par- 
ticular foodstuff'  is  detrimental  to  healthy  existence.  Nitrogenous  food,  for 
example,  is  essential  to  life,  but  so  are  salts  and  water,  and  so,  again,  are 
fats  and  carbohydrates.  And  although  the  rdle  played  by  the  individual 
foodstuff'  may  be  pointed  out,  the  effect  of  the  mixture  of  foodstuffs  is  the 
chief  physiological  factor  in  considermg  food.  The  results  of  feeding  ex- 
periments (in  animals)  have  shown  that  the  proteids  taken  as  food  are,  to 
some  extent,  the  source  of  the  fat  of  the  body  and  of  the  glycogen  found  in 
the  Hver  and  muscles  ;  so  that,  besides  being  essential  to  the  life  of  the 
nitrogenous  tissues,  they  have  a  nutritive  relation  to  the  other  two  classes 
of  organic  foodstuffs,  fats  and  carbohydrates.  The  relation  of  proteids  to 
inorganic  foodstuff's  will  be  discussed  under  the  head  of  the  latter. 

Proteid-sparing  Foods 
From  what  has  been  said,  it  is  evident  that  an  excess  of  proteid  food 
would  throw  an  excess  of  work  on  the  nitrogenous  tissues.     Thus  it  is  found 
that  the  decomposition  of  proteid  in  the  body  varies  with  the  amount  taken 
as  food  ;  the  excretion  of  urea  is  greatest  with  animal  diet  and  less  with  a 
diet  of  vegetable  food  poor  in  proteid.^     To  preserve  health,  the  proteid  taken 
must  equal  that  destroyed.     No  constant  figure  can  be  given,  however,  of  the 
amount  of  proteid  taken  as  food,  for  with  every  individual  there  is  a  maxi- 
mum and  a  minimum  of  intake.    It  is  evidently  of  advantage  to  the  organism 
if  the  amount  of  proteid  taken  in  as  food  can  be  dimhiished  by  admixture 
with  other  foodstuffs,  without,  at  the  same  time,   affecting  the  organism 
injuriously,  because  the  diminution  of  proteid  food  takes  work  off  the  tissues 
and  the  digestive  organs.     Such  foodstuffs  wliich  in  a  diet  allow  the  proteid 
food  to  be  diminished  in  quantity  are  called  proteid-sparing  foods.     The 
chief  of  these  are  gelatine,  fats,  and  carbohydrates.    .Gelatine  has  not  the 
same  nutritive  value  as  myosin  of  flesh,  &c. ;  it  cannot  completely  replace 
such  proteids  in  a  diet.     But  it  has  a  certain  value,  for  on  a  diet  containing 
two  parts  of  ordinary  proteid  to  one  of  gelatiae,  an  animal  can  maintain 
health  ;  a  fact  of  both  physiological  and  practical  importance.     In  a  dog,  for 
example,  as  Voit  has  shown,  N-equilibrium  is  established  on  a  diet  in  which 
the  nitrogenous  food  consisted  of  400  grammes  proteid  and  200  grammes 
gelatine.     Gelatine  is  easily  digested  in  the  stomach,  but  is  rapidly  oxidised 
in  the  body  into  urea,  the  excess  of  which  in  the  system  causes  diuresis. 
Chondrin  and  keratin  are  far  behind  gelatme  in  nutritive  value  ;  and  as 
they  form  only  a  fractional  proportion  of  food  they  possess  no  great  practical 
value.     Weiske  and  others  have  shown  that  asparagin   (amido-succinamic 
acid)  is  a  proteid-sparing  body  in  herbivora  ;  in  carnivora  this  action  is  not 
certain.^ 

'  See  Lehmann,  Journ.  f.  p-aht.  Chemie,  Bd.  ii.  1850,  p.  447. 
*  Cf.  Konig,  op.  cit.  p.  110. 


FOOD  899 

Large  quantities  of  animal  food  (meat)  may  be  taken  :  Eanlce  took  as 
much  as  2000  grammes  (4-^-  lb.),  and  Eubner,  1400  grammes  (3  lb.),  in  a 
day.  This  is  of  no  advantage  ;  it  throws  great  work  on  the  tissues,  and, 
moreover,  such  a  diet  cannot  be  maintained  for  any  length  of  time.  Experi- 
ments are  not  wanting,  both  in  animals  and  in  man,  to  show  that  the  addition 
of  fat  to  a  diet  of  proteid  is  of  advantage.  In  a  dog,  for  example,  which  has 
a  diet  of  1200  grammes  of  flesh  daily,  more  proteid  will  be  destroyed  in 
the  body  than  is  taken  as  food,  while  an  equilibrium  between  intake 
and  destruction  of  proteid  is  obtained  if  the  diet  consist  of  500  to  GOO 
grammes  of  meat  and  200  grammes  of  fat  (Eubner).  The  addition  of  fat  has 
here  acted  as  a  proteid-sparing  food.  Carbohydrates  act  in  a  similar  manner. 
No  definite  proof  is  forthcoming,  whether  such  substances  as  coca 
(cocaine)  and  Kola  nut  (caffeine),  &c.,  are  proteid-sparing  materials :  such 
experiments  as  have  been  performed  tend  to  show  that  these  substances 
may  diminish  the  intake  of  food,  but  are  eventually  detrimental  to  the 
organism,  owing  to  the  effect  of  their  active  principles  on  the  central  nervous 
system.  They  may,  however,  have  some  use  in  hard  work,  such  as  in  forced 
marches  and  efforts  of  endurance. 

Fats. — The  use  of  fats  in  the  organism  is  that  they  are  sources  of  energy 
and  of  heat  to  the  body.  In  the  majority  of  diets  of  the  nations  of  the  world 
fat  finds  a  place,  and  in  some  cases  (that  of  the  Esquimaux)  it  is  greatly 
increased  in  the  dietary.  In  hard  work,  too,  an  excess  of  fat  is  taken.  What- 
ever the  mixture  of  fats  taken  in  as  food,  the  body-fat  always  has  the  same 
composition  :  this  fact  agrees  with  the  conclusion  that  the  deposition  and 
metabohsm  of  fat  in  the  body  is  due  to  cell- activity,  and  that  the  fat  in  part 
comes  from  the  proteid  and  from  the  carbohydrate  food. 

Carbohydrates  not  only  act  as  proteid-sparing  foods,  but  they  are  also 
fat-sparing.  They  diminish  the  consumption  of  fat  by  being  a  source  of 
energy  in  the  body,  and  thus  when  present  in  a  diet  in  which  but  little 
fat  is  present,  they  diminish  the  oxidation  of  fat  in  the  body.  They  are  also 
a  source  of  fat,  as  has  been  abundantly  proved  by  the  experiments  of  Lawes 
and  Gilbert,  and  others.  Carbohydrates,  however,  differ  from  fats  in  that  the 
amount  ingested  is  proportional  to  the  quantity  of  carbonic  acid  (COg)  excreted : 
there  is  no  such  relation  with  fats.  For  oxidation,  carbohydrates  require 
only  sufficient  oxygen  to  unite  with  their  carbon,  since  the  hydrogen  and 
oxygen  are  in  the  proportion  to  form  water  ;  but  fats  require  oxygen  to 
oxidise  their  hydrogen  as  well  as  their  carbon.  The  question  whether  fats 
and  carbohydrates  can  replace  each  other  completely  in  a  dietary  is  not  as 
yet  definitely  answered.  Practically,  however,  it  is  in  part  settled  by  a  con- 
sideration of  the  diets  used  by  civilised  nations :  in  all  of  these,  both  fats 
and  carbohydrates  find  a  place.  The  first  question,  therefore,  as  to  whether 
it  is  possible  to  maintain  health  on  a  diet  of  proteids,  fats,  salts,  and  water, 
and  on  one  of  proteids,  carbohydrates,  salts,  and  water,  is  one  of  greater 
physiological  than  of  practical  import.  It  is,  however,  an  important  point 
to  discover  in  what  proportion  fats  and  carbohydrates  are  mutually  inter- 
changeable in  a  dietary.  Carbohydrates  are  cheaper  than  fats,  and  thus 
form  a  large  part  of  the  diet  of  the  poor  ;  and  this  is  a  practical  aspect  of  the 
question.  Life  and  a  certain  degree  of  health  can  be  maintained  on  a  diet 
of  proteids,  fats,  salts,  and  water,  and  fat  seems  essential  in  the  dietary  of  man. 
If  an  excess  of  fat,  however,  be  present  in  the  diet,  it  is  not  digested,  but 
passes  away  with  the  faeces  and  favours  decomposition  in  the  digestive 
organs,  which  are  thus  put  out  of  order.  An  excess  of  carbohydrates,  on  the 
other  hand,  owing  to  the  large  bulk  of  food  taken,  also  deranges  the  digestion 
(see  under  Digestibility  of  Food,  p.  419).    The  conclusion,  therefore,  seema 


400  HYGIENE 

to  be  in  favour  of  an  admixture  of  fats  and  carbohydrates  in  the  diet.  As, 
however,  these  foodstuffs  perform  similar  functions  in  the  body,  they  can  be 
expressed  in  dietetic  terms  of  each  other  (see  Nutritive  Value  of  Food- 
stuffs, p.  401), 

Inorganic  Constituents  of  Food 

These  play  an  important  part  in  the  dietary.  Without  them,  indeed, 
life  is  no  longer  possible. 

Water  is  necessary  for  the  proper  carrying  on  of  all  the  chemical  and 
mechanical  functions  of  the  body,  for  producing  a  medium  for  the  solution  of 
the  digestive  juices,  for  aiding  the  absorption  of  the  products  of  digestion,  for 
tlie  excretion  of  substances  from  the  body,  and  for  the  dispersion  of  heat 
from  the  lungs  and  skin.  The  water  in  the  body  is  chieliy  derived  from  that 
taken  in  as  food,  but  a  portion  is  obtained  by  the  oxidation  of  the  hydrogen 
in  tissues,  about  29G  grammes  daily.  A  want  of  water  tends  rapidly  to 
death. 

Sodium  chloride  (NaCl)  is  essential  to  life ;  its  complete  withdrawal  from 
the  food  leads  to  dissolution.  Since  it  exists  in  very  small  proportion  in 
vegetable  foods,  it  is  a  necessity  to  vegetable  feeders.  In  the  making  of 
bread,  for  example,  the  sodium  chloride  added  supplies  the  deficiency  of 
sodium  and  chloride  which  exists  in  flour.  With  animal  feeders  the  use 
of  common  salt  is  not  so  peremptory,  since  the  fluid  which  bathes  muscular 
tissue  hke  other  animal  fluids  contains  a  sufficient  quantity.  The  uses  of 
chlorides  in  the  organism  are  very  important ;  they  keep  in  solution  the 
globuhns  of  the  blood  and  other  fluids  ;  they  are  closely  associated  with 
the  proteids  of  the  tissues,  although  the  utility  of  this  association  is  at 
present  unknown ;  they  are  the  source  of  the  hydrochloric  acid  of  the  gastric 
juice,  so  that  a  deficiency  of  chlorides  in  the  food  leads  to  digestive  dis- 
turbances, the  hydrochloric  acid  in  the  stomach  diminishing  while  the 
sodium  chloride  of  the  blood  is  not  affected  to  any  great  extent.^  Albumin- 
uria is  a  secondary  result  of  '  chlorine-hunger.' 

Phosphates  are  also  essential  to  hfe,  especially  to  the  growing  organism ; 
and  where  development  is  taking  place,  there  are  ahvays  present  phosphates, 
sulphur,  and  calcium.  Young  animals,  as  Kemmerich  has  shown,  when  fed 
with  food  poor  in  potassium  phosphate,  soon  die,  the  muscles  being  chiefly 
affected.  ^  In  the  body,  phosphates  are  united  with  alkalies,  sodium,  potas- 
sium, calcium,  and  macjnesittm. 

The  sodium  salts  are  in  the  form  of  normal  sodium  phosphate  (Na3P04) 
and  di-sodium  phosphate  (Na2HP04),  while  the  potassium  is  salt  in  the 
form  of  di-potassium  phosphate  only  (K2HPO4).  Phosphates,  like  chlorides, 
are  peculiarly  associated  with  proteids,  although  the  utility  of  this  association 
is  not  understood.  The  phosphates  of  calcium  and  magnesium  have  special 
functions  to  perform,  since  they  constitute  the  chief  solid  parts  of  bone. 
They  are  of  great  importance,  therefore,  to  the  growing  organism.  When 
the  food  is  deficient  in  calcium,  and  to  a  less  extent  of  magnesium,  the  bones 
of  growing  animals  are  badly  developed,  and  may  become  rickety .^  There 
is  apparently  some  relation  between  the  ingestion  of  calcium  salts  and  of 
sodium  chloride,  for  the  former  may  be  abundant  in  the  food,  and  yet  be  for 
the  most  part  excreted  in  the  faeces  combined  with  fatty  acids.  This  non- 
absorption  of  calcium,  so  important  a  body  to  the  child,  may  be  due,  as 

'  Forster,  Zeits.  f.  Biologic,  Bd.  ix.  1873,  p.  342. 
2  Pflliger's  Archiv,  Bd.  ii.  1869,  p.  85. 

^  Eoloff,  Arch.  f.  wisscn^chaftl.  u.  inaht.  Thicrhcilk.  Bd.  v.  p.  152  ;  Dusart,  De  V Inani- 
tion min&raU.     Paris,  1874. 


FOOD  401 

Forster  lias  pointed  out,  to  the  diminution  of  the  hydrochloric  acid  in  the 
gastric  juice,  owing  to  a  deficiency  of  chlorides  in  the  food  :  it  is  through 
the  acid  gastric  juice  that  calcium  salts  are  absorbed. 

The  carbonates  present  in  the  body  are  derived  from  two  sources  :  a  small 
quantity  is  taken  in  with  the  food,  but  the  greater  part  is  derived  from  the 
vegetable  acids  of  the  food — acetic,  tartaric,  citric,  malic,  and  lactic — which 
are  changed  into  carbonates  in  the  system.  Some  of  these  acids  (lactic,  for 
example)  are  probably  derived  in  part  from  the  splitting  up  of  carbohydrates 
in  the  body ;  so  that  m  this  indirect  way  carbohydrates  may  aid  in  maintain- 
ing the  alkalinity  of  the  blood  and  animal  fluids — both  the  interstitial  fluids 
of  the  tissues  and  the  alkaline  secretions,  such  as  that  of  the  salivary  glands 
and  of  the  pancreas.  Besides  this  important  function,  carbonates  in  the 
form  of  carbonate  of  calcium  form  an  integral  part  of  bony  tissue. 

Sulphates  exist  in  only  small  quantity  in  the  body  :  they  are  not  of  such 
importance  as  the  salts  already  considered,  although  organic  sulphur  (such 
as  exists  in  proteids)  is  essential  to  growth.  A  small  quantity  of  sulphates 
is  taken  in  with  the  food  and  a  little  is  formed  in  the  body  by  the  oxidation 
of  albuminous  substances  containing  sulphur. 

Iron  is  essential  to  health  and  to  life  :  it  forms  an  important  part  of  the 
haemoglobin  of  the  red  corpuscles.  It  is  contained  in  many  foods,  especially 
animal. 

Nutritive  Value  of  Foodstuffs 

In  the  preceding  section  a  short  account  has  been  given  of  the  part 
played  by  the  different  foodstuffs  in  the  body.  It  is  now  necessary  to  discuss 
their  nutritive  value.  It  is  evident  that  the  nutritive  value  of  the  salts  and 
water  of  food  is  easily  determined,  since  they  do  not  undergo  the  great 
chemical  change  that  proteids,  fats,  and  carbohydrates  do  in  the  organism.. 
Their  nutritive  value,  therefore,  may  be  expressed  in  terms  of  the  quantity 
ingested,  with  the  requisite  proportion  of  the  different  saline  constituents. 
But  with  proteids,  fats,  and  carbohydrates  the  case  is  different :  the  changes 
they  undergo  in  the  body  are  complicated,  and  the  functions  they  perform 
are  numerous,  and  at  present  incompletely  understood,  so  that  it  is  impossible 
to  so  express  their  nutritive  value  accurately.  An  approximate  estimate, 
however,  is  not  without  its  importance.  All  the  processes  of  the  body  are 
attended  with  the  manifestations  of  energy,  this  being  in  two  forms, 
mechanical  labour  and  heat.  The  process  going  on  in  all  the  cells  of  the 
body  are  thus  manifestations  of  energy.  The  contraction  of  muscles,  the 
beat  of  the  heart,  and  the  metabolism  of  cells  develop  energy  in  their  occur- 
rence. With  regard  to  mechanical  labour,  the  amount  of  energy  expended 
by  the  body  may  be  calculated  ;  a  good  day's  work,  for  example,  would  be 
equal  to  about  150,000  metre-kilogrammes.^  With  heat,  however,  it  is 
different.  The  amount  formed  in,  the  body  has  not  yet  been  accurately 
measured,  in  spite  of  numerous  experiments.  A  useful  proportion  to  recol- 
lect, however,  between  the  amount  of  mechanical  labour  and  heat  expended 
by  an  adult  in  a  fair  day's  work  is  one- sixth  or  one-fifth  mechanical  labour 
to  five-sixths  or  four-fifths  heat.  Food  is  the  means  by  which  this  loss  of 
energy  to  the  body  is  made  good.  The  foodstuffs  possess  a  certam  amount 
of  potential  energy  which  may  be  expressed  either  in  terms  of  heat  or  of 

'  The  amount  of  energy  required  to  raise  1  kilogramme  1  metre  high  is  taken  as  the 
unit  of  force  :  on  the  English  scale,  the  unit  is  a  foot-pound. 

The  amount  of  heat  required  to  raise  1  gramme  of  water  1  degree  Centigrade  is  the 
unit  of  heat,  or  1  calorie. 

VOL.    I.  D  D 


402 


HYGIENE 


mechanical  labour.  This  potential  energy  is  different  in  each  particular  kind 
of  foodstufifs,  not  only  in  the  classes  of  proteids,  fats,  and  carbohydrates,  but 
also  in  the  individual  members  of  each  of  these  classes.  The  potential  energy 
of  any  foodstuff  is  calculated  by  estimating  the  amount  of  heat  used  on  the 
complete  combustion  of  a  certain  weight  of  the  substance  ;  and  this  heat  can 
be  expressed  in  foot-poimds  or  metre-ldlogranimes  by  calculating  how  much 
work  the  heat  can  do. 

By  this  means  the  following  calculations  have  been  made  : — 


Substance — one  gramme  (ili-ied) 

Give  rise  to  gr.-degrees ' 

Metre-kilogrammes 

Casein 

5,855 

2,488 

Peptone 

4,87& 

2,072 

Ox-tlesh 

5,724  (5.103)- 

2,432  (2,161) « 

Gelatine 

5,493 

2,334 

Gluten 

6,141 

2,610 

Legumir 

5,573 

2,368 

Ox-fat 

9,686  (9,009)- 

4,116  (3,841)2 

Palmitin 

8,883 

3,775 

Stearin 

9,036 

3,840 

Olein 

8,958 

8,807 

Butter 

7,264  2 

3,077  * 

Starch 

4,479 

1,903 

Arrowroot 

3,912  2 

1,657  * 

Dextrose 

3,989 

1,674 

Maltose 

4,163 

1,769 

Cow's  milk      ...... 

5,733 

2,436 

Human  milk 

4,837 

2,055 

Potatoes 

4,234 

1,799 

VV  beaten  bread 

4,351 

1,849 

Eice 

4,806 

2,042 

Peas 

4,889 

2,077 

Alcohol 

6,980 

2,966 

Liebig's  extract  of  muscle 

4,400 

1,870 

Urea 

2,537  (2,206)- 

1,078  (934)2 

These  are  figures  for  the  complete  oxidation  of  the  foodstuffs,  but  in  the 
body  it  is  only  the  fats  and  carbohydrates  which  are  completely  oxidised  ;  the 
proteids  get  no  farther  than  the  stage  of  urea.  In  expressing,  therefore,  the 
available  potential  energy  of  food  proteids,  the  potential  energy  of  urea 
(2,537  calories)  must  be  subtracted.  One  gramme  of  dry  proteid  gives  rise  to 
about  ^  gramme  urea  ;  therefore,  according  to  Frankland's  figures,  the 
available  potential  energy  of  one  gramme  of  proteid  is  as  follows  : — 


Gr.-deg. 

Met.-kilo. 

1  gramme  of  dried  ox-flesh 

.     5,103 

2,161 

77ltnUS 

^  gramme  urea 

.        735 

311 

Available  potential  energy  of  proteid  . 

.     4,368 

1,850 

Danilewsky  gives  the  available  energy  of  one  gramme  of  albumen  as 
5,100  calories  (5,945  minus  one-third  of  2,537). 

From  what  has  been  said,  it  is  evident  that  foodstuffs  may  be  expressed 
in  equivalents  in  terms  of  energy  ;  to  foods  which  when  burnt  yield  the  same 
number  of  calories  the  term  isodynaviic  has  been  applied.  From  the  point 
of  view  of  energy  we  may  say,  therefore,  that  so  much  proteid  is  isodynamic 
with  so  much  fat  or  carbohydrate.    Eubner  has  calculated  that  100  grammes 

'  One  gramme-degree,  or  calorie,  is  equivalent  to  0-425  kilogramme-metre ;  or,  better 
expressed,  one  kilogramme-degree  is  equivalent  to  425  kilogramme-metres. 

-  Frankland,  Fhii.  Mag.  xxxii.  p.  182.  The  other  figures  are  from  Danilewsky. 
F.  Stohmann  and  others  give  somewhat  different  figures.  See  Journ.f.praktische  Cheniie, 
N.F.  Bd.  xxxi.  p.  273  ;  Bd.  xxxii.  pp.  93,  407,  420. 


FOOD  403 

of  animal  albumin  =  52  grammes  of  fat  =  114  grammes  of  starch  =  129 
grammes  of  dextrose.  Also  that  100  parts  of  fat  are  isodynamic  with  232 
parts  of  starch,  234  parts  of  cane-sugar,  and  250  parts  of  dry  dextrose, 
making  a  mean  of  250  parts  of  carbohydrate. ^ 

From  a  dietetic  point  of  view,  however,  it  is  not  so  much  a  question  of  the 
energy  developed  by  the  burning  of  the  foodstuffs  outside  the  body,  but  of  the 
amount  of  their  potential  energy  which  is  available  during  combustion  in  the 
organism.  Theoretically,  the  potential  energy  ought  to  be  equal  to  the 
energy  developed  by  them  in  the  body ;  and  this  was  Liebig's  notion  when 
he  stated  that  100  grammes  were  equivalent  to  240  grammes  of  carbohydrates 
(Rubner  says  250  grammes).  But  owing  to  the  varying  digestibility  and 
absorption  of  foodstuffs,  and  probably  to  many  metabolic  conditions  in  the 
body  with  which  we  are  at  present  imperfectly  acquainted,  only  a  portion  of 
the  potential  energy  of  foodstuffs  is  actually  available  to  the  organism. 
Eubner  has  stated  that  in  man  the  available  heat  units  for  1  gramme  of 
albumin  are  4,100 ;  1  gramme  of  fat,  9,300  ;  and  1  gramme  of  carbohydrate, 
4,100.  These  figures  differ  considerably  from  the  total  potential  energy  of 
the  foodstuffs.  By  another  method,  Pettenkofer  and  Voit  have  come  to  the 
conclusion  that  100  grammes  of  fat  is  equivalent  to  170  or  180  grammes  of 
carbohydrates  a  dietary  ;  a  conclusion  which  may  be  taken  as  more  correct 
than  deductions  from  mere  calculations  of  potential  energy. 

This  question  of  potential  energy  of  foodstuffs  is  therefore  merely  an  indi- 
cation of  their  nutritive  value  in  a  particular  direction.  To  say,  for  example, 
that  so  much  fat  is  isodynamic  in  the  body  with  so  much  carbohydrate  does 
not  mean  that  it  is  of  no  consequence  to  the  health  of  the  organism  whether 
the  non-nitrogenous  foodstuffs  of  the  diet  be  given  in  the  form  of  fat  or  of 
carbohydrate.  As  we  have  seen,  not  only  physiological  considerations,  but 
the  custom  of  communities,  have  decided  that  health  is  best  maintained  when 
carbohydrates  and  fats  form  part  of  the  diet. 

Other  points  must  be  considered  in  dealing  with  the  nutritive  value  of 
foods  and  foodstuffs :  the  chief  of  these  are  their  digestibility,  associated 
closely  with  the  changes  produced  by  cooking  and  the  preparation  of  food  and 
with  the  bulk  of  food  taken  ;  the  interaction  of  the  foodstuffs  and  the  effect 
of  adventitious  substances  in  food ;  the  effect  on  food  of  food-accessories. 
These  subjects  will  be  discussed  afterwards. 

Another  question  arises  in  considering  the  nutritive  value  of  foods,  and 
that  is  whether  individual  members  of  the  classes  of  proteids,  fats,  and  carbo- 
hydrates do  not  differ  from  each  other  in  nutritive  value.  There  is  not  much 
known  on  this  point.  We  have  seen  that  among  proteids,  the  members  of 
the  sub-class  of  albuminoids  (gelatine,  &c.),  have  not  the  same  nutritive  value 
as  ordinary  proteids  ;  but  it  is  usually  considered  that  the  animal  proteids 
(myosin,  egg-albumin,  &c.)  have  the  same  nutritive  value  as  the  vegetable 
proteids  (gluten,  legumin,  &c.)  This  has  been  confirmed  by  the  carefully 
conducted  experiments  of  Dr.  Rutgers  on  himself.^  There  are,  however, 
undoubtedly  individual  differences  in  nutritive  value  in  proteids,  which 
further  research  will  perhaps  elucidate  ;  but  these  differences  are  perhaps 
not  great,  and  it  may  be  concluded  that  man  has  chosen  the  three  best  pro- 
teids for  his  food  in  the  myosin  of  meat,  the  casein  of  milk,  and  the  gluten 
of  bread. 

The  differences  in  nutritive  value  of  fats  seem  to  depend  almost  solely 
on  their  digestibility  (see  p.  420). 

'  Zeits.  /.  Biol.  1883,  p.  312.     Quoted  by  Konig. 
=  Zeits.  filr  Biol.  Bd.  xxiv.  1887,  p.  351. 

D  D  2 


404  HYGIENE 

The  differences  in  carbohydrate  foods  cannot  at  present  be  correctly 
estimated.  There  is  very  httle  evidence  to  show  that  starch,  dextrose, 
maltose,  and  cane-sugar  differ  in  nutritive  value.  Lawes  and  Gilbert,  how- 
ever, consider  that  cane-sugar  is  rather  more  fattening  than  starch.^ 

The  question  as  to  the  most  advantageous  form  in  which  to  take  proteids, 
fats,  and  carbohydrates  is  not  simply  one  of  the  nutritive  value  of  mixed 
foods — such  as  meat,  bread,  potatoes,  &c. — it  is  a  question  of  digestibility,  bulk 
of  food,  &c. ;  so  that  the  discussion  of  this  point  is  best  taken  under  the  con- 
sideration of  diet. 

Diet  and  Dietaries 

To  preserve  health,  a  diet  containing  proteids,  fats,  and  carbohydrates, 
with  salts  and  water,  is  necessary.  It  has  been  pointed  out  that  proteids,  salts, 
and  water  are  essential  to  life ;  and  it  has  been  shortly  discussed  to  what 
extent  fats  and  carbohydrates  are  mutually  interchangeable  in  a  dietary. 
Whatever  may  be  the  physiological  import  of  the  interchangeability  of  fats 
and  carbohydrates,  the  question  is  practically  settled  by  the  consideration 
that  both  in  the  diets  of  nations  and  in  the  standard  diets  calculated  from  labo- 
rious research  it  has  been  found  advantageous  to  include  both  fats  and  carbo- 
hydrates. For  practical  purposes,  therefore  (and  diet  is  essentially  a  practical 
question),  we  cannot  consider  the  two  classes  of  non-nitrogenous  organic 
foodstuff's  as  completely  interchangeable,  notwithstanding,  as  has  been  pre- 
viously pointed  out,  the  fact  that  their  physiological  roles  are  very  similar. 

Under  the  heading  Diet  we  have  to  consider  the  quantity  of  foodstuffs 
requisite  to  preserve  health.  This  quantity  is,  however,  not  fixed  ;  each  indi- 
vidual differs  in  the  amount  of  food  required  to  support  health,  and  in  each 
individual  there  is  a  minimum  and  maximum  of  the  daily  ingesta,  beyond 
the  bounds  of  which  health  is  not  maintained.  Diet  is  also  affected  by 
several  conditions.  To  some  extent  sex  influences  it :  age  greatly  affects  the 
daily  ingestion  of  food ;  the  dietary  of  childhood  (the  period  of  growth),  that 
of  adult  hfe  (the  period  of  vigour),  and  that  of  old  age  (the  period  of  decay 
or  of  inactivity)  differing  in  important  particulars.  Work  has  great  influ- 
ence on  diet ;  climate  and  the  temperature  of  the  air  have  only  a  slight  effect. 

The  standard  diets  which  have  been  compiled  from  the  results  of  experi- 
ments vary  to  some  extent  in  the  quantity  of  foodstuffs  contained  in  them, 
so  that  they  can  only  be  considered  as  approximate.  The  methods  by  which 
they  have  been  obtained  may  be  briefly  stated.  A  healthy  individual  is 
selected,  and  the  exact  quantity  of  foodstuffs  is  estimated  by  experiment, 
requisite  to  preserve  an  equilibrium  between  the  amount  of  carbon  and 
nitrogen  taken  into  the  body  and  that  discharged  from  it.  This  method  has, 
however,  to  be  corrected  by  two  other  methods — 1,  estimating  the  amount  of 
foodstuffs  present  in  the  daily  food  used  by  communities  of  men,  that  used  in 
famihes,  by  labourers  of  a  class,  and  in  ships  ;  2,  by  weighing  the  amount  of 
daily  food  uniformly  used  by  a  single  healthy  individual,  and  then  estimating 
the  quantity  of  combustible  foodstuffs. 

By  experiments  of  this  kind,  the  diets  of  subsistence,  during  rest  and 
during  tvork,  have  been  calculated.  The  diet  of  subsistence  is  of  physiological 
interest  only,  because  it  is  calculated  only  in  proportion  to  the  internal 
needs  of  the  organism.  But  such  absolute  rest  is  not  possible  in  health  ;  so 
that  on  a  subsistence  diet  a  man  would  waste.  The  diet  of  rest  implies 
very  little  exercise  :  that  of  work  varies  with  the  amount  of  work  done. 

In  the  following  tables  the  foodstuffs  are  reckoned  in  grammes  as  water- 
free,   the   daily  amount  of  water  requisite  being  placed  under  a  separate 

'  Brit.  Assoc.  Be])ort,  1854. 


FOOD 


W. 


Iisading,  and  the  calculation  is  for  a  man  of  average  weight,  68  kilogrammes, 
or  150  pounds. 


- 

Subsistence  diet 
(Smith  and  Play  fair)' 

Average  diet  of  rest 
(weight  of  man,  60-70  kg.) 

Proteid 

Fat 

Carbohydrate. 

Salts 

Total 

Grammes 

06 

24 

330 

14 

Oz.  avoir. 

2-32 

0-84 

11-5 

0-5 

Grammes 

100 

50 

400 

Oz.  avoir. 

3-52 

1-76 

14-08 

434 

15-16 

— 

— 

The  diet  of  rest,  however,  varies  like  other  diets.  Thus  Pettenkofer  and 
Toit  ^  found  that  in  a  strong  workman,  during  rest,  the  diet  contains  137 
grammes  of  proteid,  72  of  fat,  and  352  of  carbohydrate.  He  gave,  moreover, 
to  a  resting  soldier  a  diet  containing  86"3  grammes  of  proteid,  108*9  grammes 
of  fat,  and  331-4  grammes  of  carbohydrate,  and  found  that  he  lost  10  grammes 
of  proteid  daily  from  the  body. 

Diet  for  a  Man  iveighing  150  lb.  during  Work 


- 

Medium  work 

Severe  work 

Very   laborious 
work 

Molescliott 

Pettenkofer 
and  Voit 

Eanke 

llolescliott 

Smith  &  Play- 
fair  (average) 

Proteid  . 

Fat        .        .        . 

Carbohydrate 

Salts      . 

Total  dry  food   . 

Gr. 
130 

84 
404 

30 

Oz.  av. 
4-59 
2-96 

14-26 
1-06 

Gr. 
137 
117 
352 

30 

Oz.  av. 
4-83 
4-12 

12-40 
1-06 

Gr. 
100 
100 
240 
25 

Oz.  av. 
3-52 
3-52 
8-46 
0-89 

Gr. 
140 

90 
434 

32 

Oz.  av. 
4-94 
3-17 

15-31 
1-13 

Gr. 
184 

71 
570 

40 

Oz.  av. 
6-50 
2-85 

20-10 
1-40 

648 

22-87 

636 

22-41 

465 

16-39 

696 

24-55 

865 

30-85 

Of  these  diets,  that  of  Moleschott's  for  medium  work  has  been  taken  as 
the  average  diet  for  the  adult  man.  Eanke's  diet,  which  is  superior  in  that 
it  contains  more  fat,  was  calculated  from  experiments  on  an  individual  whose 
body- weight  was  74  kilogrammes  (163  pounds). 

Relation  of  Total  Water-free  Food  in  Daily  Diet  to  Body-weight 


- 

Subsistence 
diet 

Medium  work 

Very 

laborious 

work 

Moleschott 

Eanke 

Proportion  per  kilo,  of  body-weight     . 
Proportion  of  total  body-weight  . 

6-4 

1^6 

9-5 

1 

105 

6-3 

Grammes 

12-7 

1 

78 

From  this  table  it  will  be  seen  that  Eanke's  diet  for  medium  work  is 
actually  less  than  Playfair's  subsistence  diet,  and  differs  greatly  from 
Moleschott's.  Eanke's  results  may  be  taken  as  true  for  the  particular  indi- 
vidual experimented  upon,  but  Moleschott's  is  a  better  average  diet. 

Amount  of  Garhon  and  Nitrogen  in  Diets. — The  carbon  and  nitrogen  of 
the  foodstuffs  are  the  chief  elements  which  undergo  metabohsm  in  the  body ; 
and  from  one  point  of  view  the  food  ingested  may  be  looked  upon  as  so  much 
carbon,  nitrogen,  hydrogen,  and  salts. 

>  See  E.  Smith,  Ann.  Report  to  Privy    Council,  1863   and   1864 ;    also    Playlair, 
Edinburgh  Med.  PJiilosopMcal  Journal,  1854. 
2  Zeits.  f.  Biol.  Bd.  ii.  1866,  p.  488. 


406 


HYGIENE 


The  following  table  shows  the  quantity  of  carbon,  nitrogen,  &c.,  in  100 
grammes  of  each  dried  foodstuff : 


100  grammes  of  dried  foodstuff  contain  of 

Carbon 

Nitrogen 

Hydrogen 

Sulphur 

Proteid  (average) 

Fat 

Carbohydrates  : 

Starch 

Cane-sugar 

Lactose 

Glucose          

530 

76-5 

411 
42-1 
42- 1 
400 

16-1 

7-1 
10-9 

115 

Converting  Moleschott's  diet  into   terms  of  carbon,  nitrogen,  &c.,  we 
obtain  the  followLna:  ficfures  : — 


Nitrogen  . 

20-9  grammes 

or  321  grains 

Carbon 

.     307-0 

4,737     „ 

Hydrogen 

.       11-6 

179     „ 

Sulphur    . 

1-8 

28     „ 

Salts 

.       30-0 

464     „ 

Eoughly  speaking,  therefore,  the  average  diet  ouglit  to  contain  in  the- 
form  of  foodstuffs  20  grammes  of  nitrogen  and  300  grammes  of  carbon. 

Salts  and  Water  of  the  Diet. — -The  loss  of  water  from  the  lungs  and  skin, 
and  in  the  urme  and  fteces,  is  continuous,  but  varies  during  rest,  during  work, 
and  with  changes  of  external  temperature.  Pettenkofer  and  Voit '  give  the 
following  figures  for  rest  and  work  : — 

Daily  Loss  of  Water  from  Body  in  Grammes 


- 

During  rest 

During  work 

By  urine 

By  faeces 

By  skin  and  lungs 

Total        .... 

Grammes 
1,200 
110 
930 

Grammes 
1,150 
80 
1,730 

2,240 

2,960 

Part  of  the  water  lost  is  replaced  by  the  combustion  of  hydrogen  in  the 
body  :  this  is  equal  to  296  grammes  daily  ;  the  remainder  is  made  up  by  the 
water  taken  in  with  the  food,  which  varies  from  2,700  to  2,800  grammes  daily 
(70  to  80  ounces). 

The  total  amount  of  salts  needed  daily  has  been  already  given,  viz.  30 
grammes.  These  salts  consist  of  chlorides  and  phosphates  united  with 
sodium,  potassium,  calcium,  and  magnesium.  Iron  is  taken  in  the  food 
united  with  complex  organic  compounds. 

The  chief  salts  taken  in  as  food  are  sodium  chloride,  potassium,  calcium, 
and  magnesium  phosphates  ;  the  first  chiefly  from  animal  foods  or  added  to 
the  food,  the  latter  chiefly  from  vegetable  food ;  milk,  however,  contains  a 
sufficient  proportion,  not  only  of  sodium  chloride,  but  of  potassium  and 
calcium  phosphates  and  iron.  Owing  to  the  deficiency  of  sodium  chloride 
in  vegetable  food,  it  is  a  necessity  which  is  added  to  the  food  of  those  who 
feed  chiefly  on  carbohydrates  and  plant  proteids ;  the  animal  feeder,  on  the 
other  hand,  gets  a  sufficiency  of  sodium  chloride  in  his  food ;  and  when 
added  to  animal  food,  sodium  chloride  is  more  of  a  condiment  than  a  food. 
More  sodium   chloride  is   necessary  to  vegetable  feeders,  because  in  man. 

'  Zeits.  f.  Biol.  Bd.  ii.  1866,  p.  459. 


FOOD 


407 


potassium  salts  increase  the  excretion  of  sodium  cliloride  in  the  urine.  In 
vegetable  food  there  is  twice  or  three  times  the  amount  of  potassium  salts 
that  exists  in  animal  food  (see  sections  on  separate  foodstuffs). 

Influence  of  Constitution  and  Work  on  Diet. — It  has  been  stated  that  there 
are  great  individual  differences  in  the  diets,  due  chiefly  to  the  different  physio- 
logical conditions  of  men  and  to  the  different  surrounding  conditions.  The 
chief  difference  between  the  diets  of  men,  however,  is  duo  to  the  amount  of 
mechanical  labour  they  perform.  The  greater  the  work  done,  the  larger 
the  amount  of  food  necessary,  and  in  the  diet  (see  table)  the  proteids  and 
fats  are  chiefly  increased.  Although  work  does  not  increase  the  excretion  of 
nitrogen,  as  has  been  shown  by  the  experiments  of  Fick  and  Wislicenus  and 
others,  yet  by  work  the  living  nitrogenous  muscle  is  made  physiologically 
active :  this  leads  to  partially  using  up  the  muscle  substance,  which  has 
to  be  replaced  by  the  taking  in  of  nitrogenous  food.  Moreover,  the  increase 
of  proteids  in  the  diet  is  necessary  for  the  hypertrophy  of  the  muscles  which 
occurs  during  prolonged  efforts. 

The  influence  of  sex  on  diet  rests  chiefly  on  the  greater  manual  work  that 
men  do ;  the  woman's  diet  being  |  to  -^  that  of  the  man's.  An  increased 
amount  of  food  is  taken  by  the  woman  during  lactation,  and  probably  during 
gestation  also. 

Climate  influences  diet  to  some  extent.  Thus  in  cold  countries  the  fat 
of  the  diet  is  increased.  Great  stress  has  been  laid  on  the  fact  that  some 
of  the  nationalities  in  India  subsist  chiefly  on  carbohydrate  food  and  do 
great  work  on  it.  Carbohydrates,  however,  do  not  form  a  large  part  of  the 
diet  if  animal  food  can  be  procured  ;  so  that  its  extensive  use  is  due  more  to 
economical  necessities  than  to  its  being  advantageous. 

Influence  of  Age. — Diet  varies  in  childhood  and  in  old  age  from  that  which 
we  have  discussed  as  essential  to  health  in  adult  life.  During  childhood, 
from  birth  to  puberty,  the  organism  is  growing,  tissues  are  developing, 
especially  the  nervous,  muscular,  and  bony  tissues ;  food  has  to  be  supplied 
for  the  growth  of  these  tissues,  as  well  as  to  maintain  the  nitrogen- 
equilibrium  of  the  body.  In  old  age  less  food  is  required  than  in  adult 
life,  owing  to  the  diminished  metabolism  of  the  body  and  the  cessation  of 
mechanical  labour.     In  old  age  there  is  diminished  excretion  of  carbonic  acid. 

Childhood. — During  the  first  six  months  of  life,  the  child  grows  rapidly. 
According  to  Vierordt,  during  this  time  it  gains  from  120  to  300  grammes  (4*5 
to  10"5  ounces)  per  week  ;  during  the  second  six  months  the  gain  is  less, 
being  100  to  200  grammes  weekly  ;  while  during  the  second  year  it  is  50  to  100 
grammes  a  week.^  The  rapidity  of  gain  of  weight  then  diminishes  up  to 
puberty. . 

The  following  table  ^  shows  the  minimum  daily  need  of  foodstuffs  at 
different  ages  : — 


Coudition 

WeigM  in  grammes 

Proteid 

Pat 

Carbohydrates 

Child  up  to  Ih  year  (average) 
,,     from  6-15  years  (average)  . 

Man  (moderate  work) 

Woman  (moderate  work)       .... 

Old  man 

Old  woman 

20-36 
70-80 
118 

92 
100 

80 

30-45 
37-50 

56 

44 

68 

60 

60-90 
250-400 
500 
400 
350 
260 

Physiologie  des  Xindesalters.     Tubingen,  1877. 

Konig,  Procent.-Zusammensetzung  der  menschl.  Nahrungs-Mittel,  &c.  Berlin,  1888. 


408 


HYGIENE 


The  carbohydrate  and  fat  in  the  diet  of  the  child  is  proportional  to  the 
carbonic  acid  excreted.  Of  mineral  foods,  besides  sodium  chloride  calcium 
and  magnesium  salts  and  phosphates  are  most  essential  to  the  child.  About 
5  per  cent,  of  the  food  is  undigested  in  children. 

The  diet  of  children  varies  with  rapidity  of  growth,  and  also  in  different 
individuals.  The  daily  minimum  necessary  for  growing  children  is  as 
follows  : — 

Of  proteid  .         .  2-3  to    3-0  grammes  pur  kilogramme  of  body-weight ; 

Of  fat  .         .  2-1  to    2-6 

Of  carbohydrate    9-5  to  12-3  „ 

Meat,  milk  (milk  products),  bread,  and  flour  make  up  the  diet  of  children, 
peas,  potatoes,  and  other  vegetables  being  adjuncts  only.  One  litre  of  milk 
(35  ounces)  contains  half  the  proteids  required  by  the  child  daily — i.e.  about 
38  grammes  (see  p.  429).  Up  to  the  fourth  year  of  age  milk  forms  practically 
half  the  diet  of  the  child  ;  from  that  age  to  the  eleventh  year  it  forms  about 
one-third  (Camerer).  From  the  fourth  year,  also,  the  vegetable  food  is  in- 
creased in  the  diet. 

A  complete  daily  diet  for  children  of  six  to  seventeen  years  is  as  follows  :  ^ 


Article  of  food 

Weight  in 

Proteids 

Fat 

Carbohydi-ates 

Meat  (raw) 

Bread         .... 
Potatoes     .... 
Fat  (butter  and  lard) 

Milk 

Flour  (for  soup) 
Vegetables  (various)  . 

Total      . 

Grammes 
170 
300 
180 
15 
250 
100 
180 

Oz.  avoir. 

6-0 
10-5 
6-3 
0-5 
8-8 
3-5 
6-3 

Grammes 
300 
19-5 
3-0 

8-5 

100 

7-0 

Granmies 
17-0 
1-0 
0-3 
140 
90 
10 
10 

Grammes 

150 
36 

12 

74 

9 

1,195 

41-9 

78-0 

43-3 

281 

To  such  a  diet  must  be  added  food-accessories,  such  as  coffee,  tea,  chocolate, 
and  flavouring  materials. 

The  diet  of  old  age,  which  is  given  on  p.  407,  is  important  for  considera- 
tion in  public  institutions,  almshouses,  &c.,  where  the  aged  poor  are  eared  for. 
The  figures  given  above  represent  the  minimum  diet ;  but  in  many  institutions 
less  food  is  taken.  Thus  Forster  found  in  an  almshouse  that  each  man  re- 
ceived daily  91*5  grammes  of  proteid,  45'2  grammesof  fat,  and  331  "6  grammes 
of  carbohydrates,  part  of  the  food  consisting  of  171  grammes  of  meat  (without 
bone)  and  282  grammes  of  bread  ;  each  woman  received  79*1  grammes  of 
proteids,  48*6  grammes  of  fat,  and  265"1  grammes  of  carbohydrates,  partly 
contained  in  94  grammes  of  meat  (without  bone)  and  259  grammes  of  bread, 
with  cheese. 

The  Proportion  of  Nitrogenous  to  Non-nitrogenous  Foodstuffs  in  a  Diet. — 
The  amount  of  proteid  daily  necessary  for  the  organism  is  a  more  or  less 
constant  quantity  ;  as  we  have  seen,  a  certain  minimum  must  be  ingested  to 
feed  the  nitrogenous  tissues,  to  maintain  the  N-equilibrium,  and  to  carry  out 
the  other  functions  of  proteid  food  which  have  been  already  indicated.  As 
we  have  seen,  also,  the  functions  performed  by  the  non -nitrogenous  organic 
foodstuffs— fats  and  carbohydrates — in  the  organism  are  more  or  less  similar, 
though  there  are  reasons  why  both  forms  should  be  included  in  a  diet.  We 
have  now  to  consider  the  proportion  between  the  nitrogenous  and  non- 
nitrogenous  foodstuffs  in  different  diets,  and  also  between  fats  and  carbo- 
'  Konig,  Zusammensetzimtj  der  menschl.  Nahrungs-Mittel,  Bd.  i.  1889,  p.  149. 


FOOD 


409 


hydrates  ;  in  other  words,  with  regard  to  the  latter  question,  what  proportion 
between  fats  and  carbohydrates  is  the  most  advantageous  in  a  diet. 

From  numerous  experiments,  it  has  been  concluded  that  the  proportion 
between  the  nitrogenous  and  non-nitrogenous  organic  foodstuffs  in  a  diet 
ought  to  be  as  1  to  3'5  or  4*5  ;  this  is  the  average.  Thus,  in  Moleschott's  diet, 
the  proteids  (130  grammes)  are  to  the  non-nitrogenous  (fats,  84  grammes 
+  carbohydrates  404)  as  130  :  488,  or  1  :  3-9.  And  this  relation  is  preserved, 
not  only  in  the  diets  of  adults  in  moderate  work,  but  in  the  diet  of  laborious 
work,  in  that  of  childhood,  and  in  that  of  old  age. 

Taking  Pettenkofer  and  Voit's  conclusion  that  100  grammes  of  fat  is  iso- 
dynamic  with  175  grammes  of  carbohydrate  (p.  403),  we  may  express  the  non- 
nitrogenous  organic  foodstuffs  of  a  diet  in  terms  either  of  fat  or  of  carbohydrate. 
Thus,  taking  Moleschott's  diet,  containing  84  grammes  of  fat  and  404  grammes 
of  carbohydrate  daily,  the  non -nitrogenous  foodstuffs  would  be  expressed — 


a.  In  the  form  of  Fat 

84  grammes  of  fat 

404  grammes  of  carbohydrate,  equal  to  (175  =  100) , 

fc.  In  the  form  of  Carbohydrate 
84  grammes  of  fat,  equal  to  (100  =  175)  . 
404  grammes  of  carbohydrate  .         r         .         • 


84 
231 

315  grammes 

147 
404 

551  grammes 


In  one  case,  therefore,  the  non-nitrogenous  foodstuffs  would  be  taken  in 
the  form  of  315  grammes  fat ;  in  the  other  of  561  grammes  carbohydrate. 
We  shall  see  reasons  why  neither  of  these  modes  of  taking  non-nitrogenous 
food  is  advantageous.  In  the  following  table'  the  proportion  of  fat  to 
carbohydrates  is  given  for  diets  under  different  conditions. 


Fat  in  the  diet  of                               is  as  1  to 

Child  at  breast    .... 

1-4 

carbohydrate 

Child  five  months  old  . 

1-4 

Workman's  child 

5-6 

Adult  (in  easy  circumstances) 

3-4 

Adult  workman   .... 

5-0 

Old  man 

51 

Old  woman 

5-3 

Nursing  woman  .... 

2-4 

According  to  Voit,^  the  proportion  of  fat  to  carbohydrates  in  the  daily  diet 
ought  not  to  be  less  than  1  to  9,  which  would  mean  56  grammes  of  fat  and 
500  grammes  of  carbohydrates.  Increase  of  carbohydrate  above  this  amount 
is  disadvantageous  to  the  organism.  We  have  seen  that  fat  is  increased  in 
the  diet  when  laborious  work  is  performed,  and  in  very  cold  cUmates,  its 
great  potential  energy  being  of  service  to  the  organism.^  Carbohydrates  are 
increased  in  a  diet  out  of  the  standard  proportion  to  fat  in  the  food  of  the 
poor,  because  they  are  cheaper,  the  chief  part  of  the  fat  of  food  being  derived 
from  animal  food,  which  is  dearer  than  vegetable.  As  wages  improve,  how- 
ever, the  carbohydrates  are  diminished  and  more  animal  food  and  fat  are  taken. 

For  the  effects  of  an  excess  of  fat  and  of  carbohydrates  on  digestion,  see 
Digestibility  of  Food  (p.  420). 

1  Forster,  art. '  Ernahrung,'  Ziemssen's  Handbuch,  p.  137. 

*  Quoted  by  Forster,  loc.  cit. 

*  Potential  energy  of  one  gramme  of  fat  =  9,070  calories  (Frankland) ;  of  one  gramme  of 
grape-sugar,  3,939  calories  (Von  Eeichenberg). 


410  HYGIENE 

Construction  of  Diets  with  Articles  of  Food 
The  particular  dietary  of  a  race  is  the  result  of  ancient  traditional  rules, 

purely  empirical ;  these  rules  naturally  alter  with  the  varying  surrounding 

conditions  and  modes  of  life  of  the  people.     It  would  be  out  of  place  here  to 

deal  with  the  various  diets  of  different  races  ;  only  the  diet  of  civihsed  peoples 

will  be  discussed. 

The  construction  of  a  dietary  and  the  examination  of  a  given  diet  are  of 

importance,  not  so  much  to  the  well-to-do,  but  to  soldiers,  sailors,  and  other 

collections  of  indi\-iduals  who  are  fed  en  masse. 

It  will  be  well  to  recapitulate  the  several  points  to  which  attention  must 

be  directed  in  regard  to  food : — 

1.  The  necessary  daily  quantity  of  foodstuffs  has  already  been  discussed. 
It  varies  with  childhood,  adult  hfe,  and  old  age,  and  with  the  amount  of 
mechanical  labour  performed.  The  last  point  is  important,  and  it  necessitates 
an  increase  in  the  organic  constituents  of  the  diet. 

2.  Even  though  the  daily  necessary  amount  of  foodstuffs  may  be  ingested 
the  body  may  suffer,  and  this  is  due  to  several  causes  : — 

(a)  Conditions  of  digestibility  ;  the  food  being  rendered  indigestible  by 
being  taken  in  too  great  bulk,  or  by  containing  a  large  amount  of  cellulose, 
or  by  being  too  acid,  or  by  being  badly  cooked. 

(b)  The  flavouring  may  be  deficient  or  of  too  uniform  a  character.  In 
large  institutions  the  condition  of  the  inmates  is  materially  improved  in 
some  cases  by  attending  to  this  point. 

(c)  If  one  food  is  continued  for  too  long  a  time,  it  is  finally  refused  or  not 
eaten  with  relish. 

No  mere  calculation,  therefore,  of  the  amount  of  foodstuffs  can  gauge  the 
efficacy  of  a  particular  diet.  The  other  conditions  just  mentioned  must  be 
also  considered. 

Milk  has  been  considered  by  some  as  the  type  of  a  perfect  food.  It 
contains  4  per  cent,  (by  weight)  of  proteid,  in  the  form  chiefly  of  casein, 
but  also  as  albumin  in  very  small  quantity ;  '  3'7  per  cent,  of  fat  (butter) ; 
4-8  per  cent,  of  carbohydrates  in  the  form  of  lactose  ;  and  0"7  per  cent,  of 
salts,  with  8G-8  per  cent,  of  water.  The  proportion  between  the  proteids  and 
the  non-nitrogenous  organic  foodstuff  is  as  1  to  2-125,  and  the  proportion  of 
fat  to  carbohydrates  is  as  1  to  1*4.  In  cow's  milk,  therefore,  the  proportion 
of  nitrogenous  to  non-nitrogenous  foodstuffs  does  not  reach  the  normal, 
which  is  1  to  3-5  or  4-5.  Cow's  milk  is  therefore  not  a  perfect  food  for  man. 
In  human  milk,  however,  which  contains  less  proteids  than  cow's  milk,  but 
more  carbohydrates,  this  ratio  is  as  1  to  4.  Human  milk  is  therefore  more 
suited  to  the  child  than  cow's  milk,  and  the  latter  is  brought  up  to  the 
standard  of  human  milk  by  removing  some  of  the  casein,  by  diluting  with 
water  and  adding  carbohydrates,  such  as  sugar  (see  Milk,  p.  428). 

The  salts  of  milk  consist  mainly  of  sodium  chloride,  and  potassium  and 
calcium  phosphates.  Calcium  phosphate,  which  is  so  important  to  the  child, 
is  taken  in  greater  quantity  (four  to  five  times)  in  the  day  than  is  stored  up. 
During  the  lactating  period  about  5*5  grammes  of  calcium  phosphate  is  stored 
up  each  week,  which  is  equivalent  to  an  increase  of  weight  of  one  kilo- 
gramme in  the  first  year  (Forster).  Although  milk  is  both  scientifically  and 
practically  the  proper  food  for  children  (cow's  milk  to  a  less  extent  than 
human  milk),  for  adults  it  is  not  so  suitable,  chiefly  because  the  great  quantity 
of  water  taken  with  the  food  is  prejudicial  to  the  healthy  digestion  of  adults. 

'  What  has  been  described  as  '  lacto-protein  '  and  '  other  proteids  '  are  probably  not 
normally  present  in  milk  ;  they  are  due  to  decomposit  on  of  the  casein  and  albumin. 


FOOD 


411 


o  o 

tig 

o  hi) 
P*  o 


In  adults  the  diet 
is  mainly  composed 
of  meat  of  varying 
degrees  of  fatness, 
butter,  bread,  and  ^  ^ 
potatoes ;  these  must 
be  considered  as  the  chief 
articles  of  diet,  although  in 
some  countries  rice  and 
maize  take  the  place  of 
bread  and  potatoes  as 
carbohydrate  food. 

The  annexed  diagram, 
taken  from  Konig,  shows 
the  proportion  of  food- 
stuffs in  these  articles  of 
diet : — 

A  glance  at  the  dia- 
gram will  show  that  in 
none  of  the  articles  of  diet, 
with  the  exception  of  milk, 
is  the  proportion  between 
the  nitrogenous  and  non- 
nitrogenous  foodstuffs  as 
1  to  3-5-4-5.  In  beef  the 
proportion  is  about  4  to  1  ; 
in  eggs,  about  1  to  1  ;  in 
bread,  1  to  8  ;  m  potatoes, 
1  to  10  ;  in  peas,  1  to  2-3. 
In  peas,  therefore,  the  pro- 
portion approaches  the 
normal.  A  single  food 
is,  therefore,  on  these 
grounds  alone,  not  of  the 
composition  requisite  to 
supply  the  daily  need  of 
foodstuffs.  If  beef,  e.g., 
formed  the  sole  article  of 
diet,  an  excessive  quantity 
would  have  to  be  taken 
to  procure  the  daily  need 
of  non-nitrogenous  food. 
In  the  same  way,  if 
vegetable  food  (with  the 
exception  of  peas  and 
beans)  formed  the  chief 
article  of  diet,  a  very  large 
quantity  would  be  neces- 
sary to  obtain  the  requisite 
amount  of  proteid. 

This  is  shown  in  the 
following  table,  in  which, 
Moleschott's  diet  being 
taken  as  the  standard,  the 


1^ 


■ 


^^:;> 


m 
1 


i€§ 


g 


m 


i 

i 


^ufi 


V) 

N 

< 
111 

< 

0. 

Z 

n    -s 


5    -3 


iu     S 


b 


412 


HYGIENE 


quantities  of  foods  are  given  containing  the  daily  need  of  the  different  food- 
stuffs : — 

MolescJioWs  Daily  Diet :  Protcids  130  grammes  (4-59  oz.).  Fats  84  grammes  (2-96  oz.), 
Carbohydrates  404  grammes  (14-26  02.) 


To  obtniu 

Food 

130  gi-ammes  proteids 

84  prammes  fat 

404  grammes 

aru  rt'iiuisite 

carbohydrates 

Gr. 

Oz.  avoir. 

Cr. 

Oz.  avoir. 

Gr. 

Oz.  avoir. 

Of  beef 

604 

21-3 

1,527 

53-8 

— 

. — 

Of  eggs. 

946 

33-3 

700 

24-6 

. — 

— 

Of  milk 

3,250 

5pt.l4oz. 

2,270 

4  pts. 

— 

— 

Of  cheese 

388 

13-3 

345 

120 

. — 

— 

Of  fat  of  meat 

1,487 

52-3 

112 

3-9 

— 

— 

Of  butter       . 



— 

95 

3-3 

— 

— 

Of  lard . 



— 

84 

2-96 

— 

— 

Of  peas 

565 

20-0 

— 

— 

777 

27-4 

Of  maize 

1,300 

45-8 

1,254 

44-2 

626 

22-0 

Of  rice  . 

1,625 

57-3 

— 

— 

521 

18-3 

Of  wheaten  bread  (fine) 

1,857 

65-5 

— 

— 

732 

25-8 

Of  potatoes   . 

0,500 

229-2 

— 

— 

1.951 

65-9 

The  nutritive  value  of  the  food  articles  will  be  discussed  under  the  head- 
ing of  each.  It  is  necessary,  however,  here  to  point  out  the  most  advan- 
tageous way  in  which  these  food  articles  can  be  combined  in  a  diet.  For 
this  purpose  we  may  divide  articles  of  food  into  animal  and  vegetable,  the 
animal  foods  supplying  the  chief  part  of  the  proteids  and  the  fat  almost 
exclusively,  the  vegetable  supplying  the  carbohydrates  and  a  small  part  of 
the  proteids,  while  the  salts  come  from  both  classes  of  food,  some  vegetables 
(the  succulent  especially)  being  taken  chiefly  for  the  salts  they  contain. 

In  translating  the  elements  of  a  diet  into  terms  of  food  articles,  it  is 
essential  to  remember  (1)  the  effects  on  the  food  of  cooking  in  the  way  of 
gain  or  loss  (especially  of  salts),  and  of  physical  and  chemical  changes  in  the 
foodstuffs  (see  p.  421) ;  (2)  also  that  in  children  about  5  per  cent,  of  the  food 
consumed  is  undigested,  and  in  adults  about  10  per  cent. 

Supposing  a  simple  diet,  Moleschott's  figures  can  be  expressed  approxi- 
mately in  the  following  table  : — 


Article  of  food 

Weight  in 
gi-ammes 

Weight 
in  oz. 

Proteids 

Fat 

Carbo- 
hydrates 

Salts 

Water 

Meat     . 
Butter  . 
Milk      . 
Bread   . 
Cabbage 
Potatoes 
Sugar    . 

385 
70 

500 

225 

250 

70 

13-5 
2-4 

17-6 
7-9 

8-8 
2-4 

82-8 
2-3 

35-0 
4-5 
5-0 

21-0 
62-0 

2-5 

276-0 
11-25 
51-75 
67-4 

3-85 
1-89 

5-6 
2-25 
2-5 
3-5 

279-0 
4-0 

180-0 
202-25 
170-0 
2-0 

Total     . 

1,500 

52-6 

129-6 

85-5 

406-4 

20-59 

837-25 

The  total  weight  of  food  then  would  be  about  1,500  grammes,  to  which 
must  be  added  150  grammes  in  calculating  a  diet,  as  10  per  cent,  is  undigested, 
making  the  total  1,650  grammes. 

In  this  calculated  diet,  milk  and  fliour  may  be  with  advantage  used : 
500  cc.  of  milk  and  200  cc.  of  flour  would  replace  20  grammes  of  the  butter, 
120  grammes  of  the  potatoes,  and  220  grammes  of  the  bread. 

A  diet  with  an  excess  of  vegetable  food  or  consisting  solely  of  vegetable 
food  produces  copious  soft  fteces,  containing  a  large  quantity  of  water; 


FOOD 


413 


animal  food  produces  scanty  and  tenacious  faeces.  Comparing  a  mixed  diet 
with  a  vegetable  diet,  Schiister  found  that  the  fsBces  in  the  latter  were  (when 
dried)  more  than  double  that  in  the  former,  while  a  large  amount  of  proteid 
of  the  vegetable  diet  was  unabsorbed  (quoted  by  Forster).     Thus  : 


- 

Proteids 
In  food    1  Absorbed 

In  dried 
faeces 

Prisoner,  vegetable  diet 

Experimental  prisoner  on  mixed  diet  of  bread,  vegetables, 
milk,  and  meat  ...,..., 

104 

87 

78 
70 

70 
30 

This  would  agree  with  the  fact  that  a  large  admixture  of  indigestible 
matter  (cellulose)  with  the  food  diminishes  the  absorption  of  the  digestible 
foodstuffs — a  point  to  be  considered  more  fully  afterwards  (see  Bread). 

Another  result  of  the  excessive  or  exclusive  ingestion  of  some  forms  of 
vegetable  food  is  the  amount  of  gas  formed  in  the  intestines,  as  well  as  the 
large  amount  of  undigested  matter. ' 

The  poor  classes  use  in  their  diet  a  larger  proportion  of  carbohydrates 
than  the  well-to-do,  the  excess  of  carbohydrates  taking  the  place  of  part  of 
the  fat,  which  is  more  expensive.  With  the  labourers  inLombardy,  Bavaria, 
and  Saxony  the  carbohydrates  vary  from  800  to  1,200  grammes  in  the  daily 
diet,  while  the  proteids  are  from  140  to  180  grammes.^  An  ordinary  labourer 
will,  however,  use  much  less  carbohydrates  (450  grammes),  while  the  better 
classes  use  still  less  (325  grammes). 

Forster  ®  gives  the  following  comparison  between  part  of  the  daily  food 
of  a  young  doctor  and  a  workman  : — 


Fresh 
meat 

Bread 

Beer 

Pro 
In  form  of 
meat 

teids 
In  form  of 
bread 

Carbo- 
hydrates in 
bread 

Carbo- 

hydi-ates  in 

beer 

Workman 
Young  doctor 

G-r. 
161 
385 

Or. 
412 
150 

Co. 
1,500 
1,625 

Gr. 

35-5 

84-8 

Gr. 
44-3 
24-8 

Gr. 
287-3 

86-4 

Gr. 
78-0 
84-5 

That  is,  the  workman  takes  27  per  cent,  of  his  proteids  in  the  form  of 
meat,  the  young  doctor  65  per  cent. 

The  diet  of  the  doctor  was  richer  in  fat,  and  the  proportion  of  fat  to 
carbohydrates  in  his  diet  was  that  of  1  :  3*5  in  the  workman,  on  the  other 
hand  1  :  5-8. 

The  total  daily  amount  of  food  in  the  two  diets  may  be  thus  compared : 


- 

Proteids 

Fat 

Carbohydrates 

Water 

Proportion  of  nitrogen 
ous  to  non-nitrogenous 

Workman 
Yomig  doctor  . 

132 
131 

81 
95 

458 
332 

2,916 
2,975 

1  :  5-0 
1  :4-3 

Special  Diets 

The  study  and  correct  understanding  of  diet  are  important  to  those  able 
to  command  every  variety  of  food,  but  they  are  of  vital  importance  to  com- 
munities and  bodies  of  individuals  which  are  supported  by  the  State  or  in 

*  See  Kutgers,  Zeits.  f.  Biologic,  Bd.  xxiv.  1887,  p.  351. 

^  Quoted  by  Forster,  op.  cit.  p.  125. 

'  Op.  cit.    Also  Zeits.  f.  Biologic,  1873,  p.  351. 


114 


HYGIENE 


public  institutions.  The  diet  of  tlie  soldier  and  the  sailor  in  peace  and  war, 
of  the  working  classes,  of  prisoners,  of  those  in  almshouses,  workhouses, 
and  schools,  and,  lastly,  the  diet  of  patients  in  hospitals,  have  in  this  respect 
to  be  considered.  The  diet  of  the  sick  is  a  special  subject,  and  will  not  be 
treated  here  :  it  is  a  part  of  medical  treatment. 

In  considering  the  diet  of  such  communities  of  individuals  as  have  been 
enumerated,  not  only  must  the  food  contain  the  proper  proportion  of  food- 
stufi's,  such  as  we  have  been  considering,  but  the  food  must  be  obtainable  at 
a  certain  price,  the  object  being  to  provide  the  most  nutritious  food  at  the 
lowest  possible  cost.  And  it  is  evident  that  in  the  case  of  soldiers,  sailors, 
and  the  working  classes,  who  are  called  upon  either  continuously  or  at 
intervals  to  perform  hard  work,  the  question  of  the  energy  obtainable  by 
the  body  from  the  food  supphed  is  of  prime  importance.  In  such  classes  of 
men,  too,  the  question  of  stimulants  has  to  be  considered — stimulants  to  the 
nervous  system,  such  as  tea,  coffee,  beef-tea,  and  alcoholic  drinks.  This  last 
subject  will  be  dealt  with  under  Food-accessoeies  ;  at  present  we  are  only 
concerned  with  the  daily  amount  of  food  required  to  preserve  the  health  of 
communities  of  men. 

Soldiers'  and  Sailors'  Bations 

According  to  Parkes  ^  the  usual  food  of  the  soldier  may  be  expressed  as 
follows : — 


Articles 

Daily  quan- 
tity in  oz.  av. 

Water 

Proteids 

Fats 

Carbo- 
hydrates 

Salts 

Total  water 
per  food 

Meat 

Bread     . 

Potatoes 

Other  vegetables 

Milk       . 

Sugar    . 

Salt 

Coffee    . 

Tea 

12  (1  bone) 
240 
160 
80 
3-25 
1-33 
0-25 
0-33 
0-16 

7-20 
9-60 
11-84 
7-28 
004 

1-44 
1-92 
0-32 
0-14 
0-13 

0-81 
0-36 
002 
0-04 
012 

11-81 
3-36 
0-46 
0-16 
1-29 

0-15 
0-31 
0-02 
0-06 
002 

0-25 

2-40 
14-40 
3-72 
0-70 
0-43 
1-29 
0-25 

Total 

65-32 

37-78 

3-95 

1-35 

17-08 

0-81 

23-19 

This  dietary  contains  276  grains  of  nitrogen  and  4,588  grains  of  carbon. 
It  consists  of  112  grammes  of  proteid,  38*3  grammes  of  fat,  485  grammes 
of  carbohydrates,  and  23  grammes  of  salts  ;  and  the  proportion  of  nitro- 
genous to  non-nitrogenous  foodstuffs  is  as  1  :  4*6. 

The  diet  is,  however,  deficient  in  proteids,  and  especially  in  fat,  the  pro- 
portion of  fat  to  carbohydrate  being  1  :  12.  This  is  too  small  a  proportion 
(see  p.  409) ;  so  that  the  diet  would  be  much  improved  by  adding  butter  or 
cheese  to  it.  A  larger  quantity  of  proteids  would  also  be  obtained  by  substi- 
tuting peas  and  beans  for  the  less  nutritious  vegetables,  such  as  cabbage 
(returned  in  the  table  as  '  other  vegetables  ').  Vinegar  is  also  with  advantage 
added  to  the  food. 

The  mean  of  the  observations  of  Voit,  Artmann,  Hildesheim,  and  Play- 
fair  of  the  soldier's  daily  diet  during  peace  is  114  grammes  of  proteids,  45 
grammes  of  fat,  and  486  grammes  of  carbohydrates  ;  a  diet  closely  resembling 
that  of  the  English  soldier.  In  war  the  diet  would  be  138  grammes  of  pro- 
teids, 72  grammes  of  fat,  and  497  grammes  of  carbohydrates ;  proportion  of 


Pract.  Hygiene,  p.  516. 


FOOD 


415 


nitrogenous  to  unnitrogenous  foodstuffs  being  1  :  4'9  (mean  of  Hildeslieim, 
Artmann,  and  Playfair's  calculations).^ 

When  there  is  hard  work  to  be  done,  as  in  the  field  or  in  forced  marches, 
it  is  advantageous  to  increase  the  fat  of  the  diet,  and  to  increase  the  food- 
accessories.  The  increase  of  fat  enables  more  work  to  be  done,  and  the 
food-accessories  (tea,  coffee,  beef-tea,  &c.)  act  serviceably  as  stimulants  to 
the  nervous  system. 

In  the  Franco-Prussian  war  (1870-71)  the  German  soldier  had  daily  :  ^ 


- 

Protciil 

Fat 

Carbohydrate 

Bread,  750  grammes 

Meat,  500  grammes 

Bacon  fat,  250  grammes 

1  litre  of  beer  .... 

Total   .         .         . 

48 
100 

11 

5 

4 

15 

190 

345 

55 

164 

209 

400 

Each   man  had  also   30  grammes  of  coffee  and  60  grammes  of  tobacco. 
Such  a  diet,  rich  in  fat,  is  only  for  the  most  strenuous  exertion. 

Diet  of  the  Working  Glasses 

The  working  classes  have  to  arrange  their  diet  according  to  the  wages 
they  earn,  and  there  is  but  little  doubt  that  teaching  them  how  to  obtain 
the  most  nutritious  food  at  the  cheapest  possible  price  is  one  of  the  great 
aims  of  hygiene.  A  proper  dietary  for  the  working  classes  would  mean  the 
improved  health  of  the  larger  portion  of  the  community,  since  deficient  food 
itself  causes  disease  and  exposes  an  individual  to  the  dangers  of  infectious 
diseases. 

In  the  dietary  of  the  working  classes  in  all  parts  of  Europe  there  is  a 
deficiency  of  proteid  and  of  fat  and  an  excess  of  carbohydrates.  The 
deficiency  of  proteid  in  the  diet  is  due  to  the  fact  that  but  little  animal  food 
is  eaten ;  fat  is  deficient  from  the  same  cause. 

Voit  gives  in  the  diet  of  a  workman  and  workwoman  with  moderate  work 
the  following  minimum  as  the  daily  need  (see  also  p.  407). 


—                       1      Total  proteid 

Digestible  proteid 

Fat 

Carbohydrate 

Man         .        , 
"Woman    . 

Grammes 

118 

94 

Grammes 

106 

84 

Grammes 
54 
49 

Grammes 
500 
400 

The  woman's  diet  may  be  reckoned  as  from  three-quarters  to  four-fifths 
of  the  man's. 

The  actual  diets  used  by  the  various  classes  of  working  men  and  women 
differ  considerably  from  Voit's  figures  ;  as  seen  in  the  following  table,  taken 
from  C.  A.  Meinert,^  the  daily  food  taken  is  greatly  deficient  in  proteids  and 
fats,  a  point  which  has  been  already  mentioned.  Although  in  tliis  table  the 
diets  investigated  are  those  of  the  working  class  in  Germany,  almost  precisely 
similar  results  are  obtained  from  the  diet  of  the  Enghsh  working  class. 


'  Konig,  Zusavimensetz.  der  menschlich.  Nalirungs-  u.  Genussmittel,  1889,  ii.  156. 
also  C.  A.  Meinert,  Armee-  u.  Volks-Erncihrung,  Berlin,  1880,  i.  286. 
-  Konig,  op.  cit.  p.  160. 
*  Op.  cit.  ii.  171-260. 


Sea 


416 


HYGIENE 


Total  amt. 

Total 

Digestible 

Carbo- 

of food 

protcid 

proteid 

hydrate 

Kind  of  food 

Grammes 

Gr. 

Grammes 

Gr. 

Gramnip;; 

rence 

Poor  woikman  . 

— 

86-0 

— 

130 

GlO-0 

— 

Potatoes 

Uerlin  workman,  ob- 

taining foodchiefh' 

from  People's  Kit- 

chens    . 

— 

— 

C80 

37-0 

2900 

— 

Chiefly  vege- 

Seamstress or  book- 

table food 

binder  (female) 

846 

OO'O 

47-4 

51-4 

229-2 

41- 

Little  meat 

Painter  iii  Leipzig     . 

1,199 

86-7 

73-3 

68-6 

366-2 

5} 

Mixed  food 

Cabinet-maker  .• 

1,281 

70-5 

60-5 

57-2 

465-8 

5,V 

»» 

All  these  diets  are  those  of  poor  workpeople. 

The  question  as  to  the  means  by  which  the  poor  and  the  working  clasa 
can  obtain  the  best  food  at  the  lowest  price  is  an  important  one,  but  too  wide 
to  deal  with  fully  here.  0.  A.  Meinert  has  treated  the  subject  in  a  pamphlet 
entitled  '  ^Yie  niihrt  man  sich  gut  und  billig  ? ' '  Some  of  his  conclusions 
may  be  given  here.  A  family  is  reckoned  as  consisting  of  a  man,  wife,  and  two 
children  of  ten  to  twelve  years  of  age,  all  of  whom  together  consume  the  food 
of  three  men.  In  families  earning  15s.  6d.  to  21s.  a  week  60  per  cent,  of  the 
income  may  be  spent  on  food — that  is,  from  9s.  Gd.  to  12s.  6d.  a  week.  In 
those  earning  29s.  a  week  half  may  be  spent  on  food — that  is,  14s.  Gd.  weekly. 
For  the  table  showing  how  the  working  man  can  obtain  the  best  food  for  this 
money  Meinert's  pamphlet  must  be  consulted.-  He  reckons  that  the  two 
poorer  families  can  obtain  100  grammes  of  proteid,  50  grammes  of  fat,  and 
500  grammes  of  carbohydrate  daily  ;  while  the  family  better  off  can  obtain 
120  grammes  of  proteid,  70  grammes  of  fat,  and  500  grammes  of  carbohy- 
drate— a  diet  more  closely  resembling  the  normal  than  the  first.  In  the  first 
diet  the  proportion  of  nitrogenous  to  non-nitrogenous  foodstuff  is  as  1  :  5-5, 
of  fat  to  carbohydrate  as  1  :  10  ;  in  the  second  diet  the  proportions  are  as 
1  :  4*7  and  1  :  7.  Fat  in  a  cheap  form,  such  as  is  now  sold  as  '  margarine,' 
is  a  very  important  addition  to  the  working  man's  diet. 

Diet  in  Prisons  and  Workhouses 

A  proper  diet  in  prisons  is  one  of  the  great  preventives  of  a  large  mor- 
tality. Besides  the  evil  effects  of  bad  housing,  prisoners  are  especially  liable 
to  diseases  arising  from  food.  The  occurrence  of  scurvy  has  by  some  been 
ascribed  to  the  deficiency  of  animal  fat  in  the  food.^  This  is  perhaps 
doubtful ;  but  what  the  diet  of  prisoners  lacks  chiefly  is  animal  proteid  and 
fat.  The  diet  is  chiefly  vegetable,  and  this  may  lead  to  all  the  trouble 
which  an  almost  exclusively  vegetable  (carbohydrate)  diet  causes.  The  un- 
palatable mode  of  preparation  of  the  food  is  also  a  great  drawback  in  the  food 
of  prisoners. 

In  Prussian  prisons  since  1872,  210  grammes  (about  7oz.)  of  meat  are 
given  weekly;  in  Belgian,  400  grammes  (about  14  oz.)  ;  in  Pentonville,  117 
grammes  (4  oz.)  are  given  daily  ;  and  in  Portland,  with  hard  labour,  175- 
grammes  (6  oz.)  is  the  daily  allowance."* 

The  average  amount  of  foodstuffs  present  in  the  different  food  articles 


'  Berlin,  1882.     E.  S.  Mittler  u.  Sohn. 

^  Abstracted  also  in  Konig,  op.  cit.  i.  165.  For  England,  the  amount  capable  of  being 
spent  on  food  is  proportionately  less,  since  the  rent  is  greater  on  the  average  than  in 
Germany. 

»  Eonig,  O]o.  cit.  p.  171.  *  Ihid.  p.  171. 


FOOD 


417 


used  may  be  calculated  from  Richter's  results  : '  108  grammes  of  proteid,  26 
grammes  of  fat,  and  551  grammes  of  carbohydrate  ;  a  diet  far  behind  the 
minimum  diet  of  a  workman  with  moderate  work,  which  is  118  grammes  of 
proteid,  56  grammes  of  fat,  and  500  grammes  of  carbohydrate  (Voit). 

The  diet  in  orphan  asylums  and  other  institutions,  where  the  young  are 
cared  for,  and  that  in  almshouses,  where  there  are  the  aged  poor,  must  be 
regulated  on  the  data  given  on  p.  408.'^ 

Arrangement  of  the  Daily  Food  in  Meals 

But  little  can  be  said  on  this  subject  here.  Although  as  a  rule  it  is  a 
matter  of  custom,  the  meals  being  taken  at  the  times  most  convenient  to  the 
different  classes  of  society,  yet  there  are  a  few  general  considerations  which 
are  important.  Food  is  usually  taken  three  or  four  times  daily,  the  largest 
meal  being  taken  midday  or  in  the  evening.     About  one-half  of  the  tt)tal 


- 

In  100  parts 

Water 

Proteids 

Fats 

Carbo- 
hydrates 

Salts 

Cellulose 

Beef,  witli   little    fat     (beef 

steak)        .... 

76-5 

21-0 

1-5 

— 

1-0 

— 

Beef  (medium  fat) 

72-5 

21-0 

5-5 

— 

1-0 

— 

Beef  (very  fat) 

55-5 

170 

26-5 

— 

1-0 

— 

Cooked  meat  (roast  or  boiled) 

54-0 

27-6 

15-45 

— 

2-95 

— 

Salt  beef  (Girardin) 

49-1 

29-6 

0-2 

— 

21-1 

— 

Salt  pork  (Girardin) 

44-1 

26-1 

7-0 

— 

22-8 

— 

Fat  pork  (Letheby) 

390 

9-8 

48-9 

— 

2-3 

— 

Dried  bacon  (Letheby) . 

150 

8-8 

73-3 

— 

2-9 

— 

White  fish  (Letheby)     . 

78-0 

18-1 

2-9 

— 

1-0 

— 

Poultry  (Letheby) 

74-0 

21-0 

3-8 

— 

1-2 

— 

Egg  (deducting  10  per  cent. 

for  shell)   .         .         . 

74-5 

12-5 

12-0 

— 

1-0 

— 

Human  milk 

87-0 

2-5 

40 

6-0 

0-5 

— 

Cow's    milk    (sp.    gr.    1029 

and  over)  .... 

87-5 

3-4 

3-6 

4-8 

0-7 

—        1 

Skimmed  milk  (Letheby) 

88-0 

4-0 

1-8 

5-4 

0-8 

— 

Cream  (Letheby)  . 

660 

2-7 

26-7 

2-8 

1-8 

— 

Cheese .         .         .         . 

36-8 

33-5 

24-3 

— 

5-4 

— 

Butter 

60 

3-3 

88-0 

— 

2-7  (avera 

ge)  — 

Bread  (fine  white  wheaten)  . 

36-0 

7-0 

0-5 

55-2 

1-0 

Whole-meal  bread  (Church) 

43-4 

10-4 

0-3 

42-7 

1-5 

1-7 

Wheat  flour  (average)  . 

12-81 

12-06 

1-36 

71-83 

0-96 

0-98 

Whole  meal  (Atwater)  . 

13-0 

11-7 

1-7 

69-9 

1-8 

1-9 

Barley  meal .... 

14-83 

11-38 

1-53 

71-22 

0-59 

0-45 

Pearl  barley  (Church)    . 

14-7 

7-3 

1-1 

75-8 

1-0 

— 

Eye  (average  composition)    . 

13-71 

11-57 

2-08 

69-61 

1-44 

1-59 

Eice 

13-0 

8-0 

1-0 

76-5 

1-0 

0-5 

Oatmeal  (Letheby) 

150 

12-6 

5-6 

63-0 

3-0 

— 

Maize 

14-21 

9-65 

3-8 

69-55 

1-33 

1-46 

Macarpni       .         .         .         . 

13-07 

9-02 

0-3 

76-77 

0-84 

— 

Millet  (Konig),  cellulose  ex- 

cluded      .         .         .         . 

12-3 

11-3 

3-6 

67-3 

2-3 

— 

Arrowroot     .         .         .         . 

15-4 

0-8 

— 

83-3 

0-27 

— 

Pea  flour  (dry) 

11-41 

25-2 

201 

57-17 

2-89 

1-32 

Potatoes        .         .         .         . 

74-98 

2-08 

0-15 

21-01 

1-09 

0-69 

Carrots  (cellulose  excluded)  . 

85-0 

1-6 

0-25 

8-4 

1-0 

— 

Cabbage        .         .         .         . 

91-0 

1-8 

0-5 

5-8 

0-7 

— 

Cane  sugar    .... 

3-0 

— 

— 

96-5 

0-5 

— 

>  Konig,  p.  171.  For  further  information  see  TJeber  Massenernahrung,  by  Baer,  Jeserich, 
and  C.  A.  Meinert,  Berlin,  1885.  '  Untersuch.  der  Kost  in  einigen  offentlichen  Anstalten.' 
By  C.  Voit.     Miinchen,  1877. 

2  The  food  supplied  in  soup-kitchens  and  other  places  for  the  working  classes  ia 
treated  in  C.  Voit's  work  already  quoted. 

VOL.  I.  E  E 


418 


HYGIENE 


daily  food  is  taken  at  the  chief  meal,  and  about  one-third  at  the  next  largest 
meal,  which  is  supper  or  luncheon  or  breakfast  according  to  custom.  For 
further  details,  see  Fiirster's  paper  in  the  Zcitschrift  fiir  Biologie  (1873, 
p.  881). 

The  taking  of  a  large  meal  late  in  the  evening  leads  to  digestive  distur- 
bances, since  during  sleep  the  process  of  digestion  is  practically  in  abeyance, 
and  the  presence  of  food  in  the  stomach  leads  to  bacterial  fermentation. 
Physiologically  speaking,  the  proper  times  for  the  man  who  is  busy  all  day 
to  have  his  chief  meals  are  at  breakfast  and  at  dinner  early  in  the  evening  ; 
and  custom  has  settled  it  so.  To  the  working  man,  however,  it  is  more 
convenient  to  have  the  largest  meal  in  the  middle  of  the  day ;  this  is,  owing 
to  his  hard  work,  a  necessity  to  him. 

The  table  on  page  41G  shows  the  proportion  of  organic  and  inorganic  food- 
stuffs in  many  articles  of  diet.' 

From  this  table  the  amount  of  foodstuff'  present  in  a  diet  can  be  estimated, 
so  as  to  test  the  efficacy  of  a  given  dietary.  Allowance  must  be  made  for 
cooking  and  for  digestibility,  as  has  been  previously  explained. 

Digestibility  of  Food 

No  mere  calculation  of  the  amount  of  nitrogen  and  carbon  or  the  amount 
of  organic  foodstuff's  in  the  diet  can  determine  the  nutritive  value  of  a  diet. 
To  be  of  use  to  the  organism  the  organic  foodstuff's  must  undergo  a  process 
of  digestion  before  they  are  absorbed.  With  the  changes  (chiefly  patholo- 
gical) Avhich  the  digestive  juices  may  undergo  and  thus  aft'ect  the  absorption 
of  food  we  are  not  here  concerned.  But  the  mixed  food  itself  may  be  of  such 
a  nature  as  to  interfere  with  its  proper  assimilation.  There  are  three  points 
which  have  to  be  considered  xmder  this  head. 

1.  The  digestibility  of  the  different  organic  foodstuffs  obtained  from  the 
animal  and  vegetable  worlds. 

2.  The  bulk  and  chemical  reaction  of  the  food  taken  ;  and  the  admixture 
of  indigestible  matter. 

3.  The  effect  of  cooking  on  the  food. 

1.  The  digestibility  of  the  organic  foodstuffs — proteids,fats,  carbohydrates. 

The  proteids  obtained  from  the  animal  kingdom  are  more  completely 
digestible  than  those  obtained  from  the  vegetable  ;  so  animal  fat  is  also  more 
digestible  than  vegetable.  This  is  shown  in  the  following  table,  constructed 
fi'om  results  obtained  by  Eubner: — 

Digestibility  of  Foodstuffs  {percentage  digested) 


—                  Meat 

Eggs 

■Wilk 

Cheese 

Bice 

Potatoes 

Peas 

Wliite 
bread 

Black 
bread 

Carrots 

Proteid 

Fat 

Carbohydrates 

97-5 
80-0 

97 
95 

92 
95 

97 
95 

80 
99 

75-0 
92-5 

80 
95 

78 
99 

68 
88 

79-5 
82-0 

From  this  table  it  is  seen  that  the  proteids  of  meat,  eggs,  milk,  and 
cheese  are  far  more  digestible  than  those  of  rice,  potatoes,  peas,  white 
bread,  &c. 

The  carbohydrates  of  rice  and  white  bread  are  the  most  digestible  ;  while 
the  fat  of  milk  is  more  digestible  than  that  of  meat. 

There  is  a  difference,  too,  in  the  digestibility  of  the  different  kinds  of  flesh. 
Using  artificial  gastric  juice,  Chittenden  and  Cummins^  have  found  that  fish 

'  Compiled  from  Parkes  and  Konig.     See  also  separate  sections  on  food  articles. 
*  Avicrican  Chem.  Journal,  No.  6,  p.  5. 


FOOD 


419 


is  more  difficult  to  digest  than  meat,  white  flesh  more  digestible  than  dark, 
raw  beef  more  digestible  than  smoked  (as  100  :  95),  while  the  presence  of  fat 
increases  the  difficulty  of  digestion.  Taking  the  digestibility  of  ox-fiesh  as 
the  standard,  100,  veal  would  be  95,  mutton  92,  lamb  88,  poultry  (fowl) 
84-86,  while  fish  would  be  about  90  (although  there  are  great  individual 
differences).  These  results  have  been  obtained  by  artificial  digestion  with 
gastric  juice.  They  are  not  so  valuable  as  the  results  of  Beaumont's  and  of 
Eichet's  experiments,  which  were  performed  on  cases  of  gastric  fistulse  in 
man.  Beaumont,  moreover,  showed  that  artificial  digestion  with  gastric 
juice  was  much  longer  in  duration  than  digestion  in  the  stomach.  In  the 
following  table  Beaumont's  and  Eichet's  results  are  given  ;  they  are  impor- 
tant from  a  dietetic  point  of  view,  for  although  many  of  the  substances 


Table  of  the  Digestibilily  of  Articles 

of  Diet  in  the  Stomach  ' 

Length  of  time  in  stomach  till  digested, 

absorbed,  or  discharged 

Food 

Preparation 

Beaumont 

Eichet 

Schnapps     .... 



— 

30-40  min. 

Milk 

— 

— ■ 

30  min.,  1  hr. 

Bice     ..... 

Boiled 

Ihr. 

— 

Peas,  with  bacon  fat    . 

— 

— 

1-2  hr.  30  min. 

Baked  potatoes    . 

— 

— 

1  h.,  2  h.  15  m.,  2-30-3  h. 

Eggs,  whipped     . 

Baw 

1  hr.  30  min. 

— 

Barley  soup 

Boiled 

1  hr.  30  min. 

— 

Salmon  trout        .         .         . 

Boiled 

1  hr.  30  min. 

— 

Flesh 

— 

— 

1  h.  30  m.,  2  h.  30  m., 
4h.,  5h.  30  m. 

Sago    ..... 

Boiled 

1  hr.  45  min. 

— 

Spinach       .... 

— 

— 

1  hr.  45  min.,  2  hr.,  4  hr. 

Tapioca        .... 

Boiled 

2hr. 

— 

Barley.         .... 

Boiled 

2hr. 

— 

Milk 

Boiled 

2hr. 

— 

Fresh  eggs  .... 

Baw 

2hr. 

— 

Cabbage,  with  vinegar 

Baw 

2  hr. 

— 

Soup,  with  fat  and  Joread     . 

Boiled 

— 

2hr. 

Bice,  with  fat      . 

— 

— 

2h.,2h.45m.,3h.,3h.l5m. 

Milk 

Unboiled 

2  hr.  15  min. 

— 

Fresh  eggs  .... 

Boasted 

2  hr.  15  min. 

— 

Ox-liver       .... 

Baw 

2  hr.  15  min. 

— 

Gelatine       .... 

Boiled 

Lamb 

Broiled 

Hash — meat  and  vegetables 
Beans  ..... 

Warmed 
Boiled 

>-2hr.  oOmin. 

— 

Potatoes       .... 

Boiled  or  roasted  1 1 

Cabbage       .... 

Boiled 

1 

Macaroni  and  fat 

Boiled 

—          12  hr.  30  min..  3hr.  45  min.! 

Eggs 

Soft  boiled 

\ 

Beef  steak   .... 

— 

"White  bread 

Baked 

Ham    .        .        . 

Boiled 

I     ghi. 

_ 

Lean  beef     .... 

Boasted 

Fish 

Boiled 

Mutton        .... 

Broiled  or  boiled 

^ 

,,              .... 

Boasted 

3  hr.  15  min. 

_- 

Pork 

Boasted 

\ 

Poultry         .... 
Veai 

Boasted 
Boasted 

■      4hr. 

— 

Brown  bread 

Baked 

Pork 

Salted 

}      5hr. 

Eggs 

Hard  boiled 

*  Beaumont,  Experiments  and  Observations  on  the  Gastric  Juice  and  the  Physiology 
of  Digestion,  Edin.  1838  (reprint).  Bichet,  Die  Stic  Gastrique  dies  VHomme  et  les 
Aniviaux,  Paris,  1878. 

£  £  2 


420  HYGIENE 

experimented  with  contain  foodstuffs,  such  as  carbohydrates  and  fats,  which 
are  not  digested  in  the  stomach,  yet  the  length  of  time  the  food  remains  in' 
that  organ  is  important,  for  the  longer  it  remains  after  a  certain  time  the 
less  is  it  acted  upon,  and  the  more  likely  is  it  to  undergo  fermentation,  and 
thus  to  cause  digestive  disturbances. 

From  this  table  the  following  conclusions  may  be  drawn  : — 

(1)  That  the  flesh  of  animals  remains  from  two  and  a  half  hours  to  five 
hours  in  the  stomach,  the  most  digestible  being  lamb,  then,  in  order,  beef 
steak,  lean  meat,  mutton,  veal  and  pork,  while  fish  is  equal  to  mutton  in 
digestibility.  • 

(2)  That  starchy  foods,  as  rice,  barley,  and  tapioca,  do  not  remain  more 
than  two  hours  in  the  stomach,  while  beans,  peas,  and  potatoes  remain  for 
two  and  a  half  hom-s,  white  bread  for  three  hours,  and  brown  bread  for  four 
hours. 

(3)  Eichet's  results,  however,  show  that,  even  for  the  same  substance  in 
the  same  subject,  there  are  varying  times  in  which  it  remains  in  the  stomach  : 
thus,  baked  potatoes  remained  sometimes  one  hour,  sometimes  two  and  a  half- 
hours,  or  even  three  hours. 

The  figures  quoted,  therefore,  only  give  broad  differences  of  digestibility 
between  foods  ;  digestions  differ  almost  as  much  as  individuals. 

The  effect  of  cooking  on  meat  is,  that  the  more  tough  the  process  makes 
the  meat,  the  more  indigestible  it  is.  Honigsberg,  comparing  the  amount  of 
peptone  formed  by  artificial  gastric  juice  from  boiled  beef  and  roasted  beef, 
found  that  in  the  digested  material  the  proportion  of  peptone  to  other  nitro- 
genous substance  in  boiled  meat  was  as  1  :  2*75,  while  in  roasted  beef  it 
was  1  :  1*03  ;  from  roasted  meat,  therefore,  more  peptone  is  formed  than 
from  boiled,  raw  meat  being  intermediate  in  digestibility '  (see  Effect  of 
Cooking). 

2.  Btdk  and  Beaction  of  Food. — The  division  of  the  daily  food  into  meals 
has  been  previously  discussed.  If  too  large  an  amount  of  the  daily  food  be 
taken  at  one  meal,  the  result  is  not  advantageous  to  the  organism.  The 
excess  of  food  throws  extra  work  on  the  stomach,  and  continued  will  end 
in  imperfect  digestion  and  assimilation,  with  the  liability  of  fermentation  of 
the  ingesta,  butyric,  lactic,  acetic,  and  other  fatty  acids  being  formed  in 
excess.  This  fermentation  is  especially  hable  to  occur  when  an  excess  of 
vegetable  (carbohydrate)  food  is  taken.  Not  only  do  the  carbohydrates 
readily  spht  up  under  the  action  of  bacteria  into  the  different  fatty  acids,  but 
most  vegetable  food  contains  the  so-called  vegetable  acids,  acetic,  tartaric, 
citric,  &c.,  either  free  or  in  the  form  of  salts,  and  these  simply  add  fuel  to  the 
fire  in  the  stomach.  Fats,  also,  both  when  neutral  and  when  containing  fatty 
acids,  may  aid  in  increasing  the  acidity  of  the  stomach's  contents  (due  to 
organic  acids),  and  thus  diminish  the  absorption  of  foods  taken  into  the 
digestive  tract.  Even  if  this  fermentation  does  not  occur,  in  some  cases  the 
food  ingested  is  imperfectly  assimilated  owing  to  its  admixture  with  indi- 
gestible matter — e.g.  cellulose.  This  result,  therefore,  occurs  when  vegetable 
food  is  chiefly  taken.  Thus,  with  a  diet  of  meat  alone,  no  muscle  fibres  are 
found  in  the  faeces,  but  they  are  observed  when  food  containing  much  cellu- 
lose is  taken  with  the  meat.-  With  brown  bread,  also,  S.  Meyer  found  that 
20  per  cent,  (dried)  was  passed  out  of  the  body,  while  with  white  bread  only 
6  per  cent.^    Kubner  has  also  shown  that  with  the  daily  use  of  960  grammes 

>  Wiener  vied.  Blatter,  1882,  p.  582. 

'^  Forster,  art.  '  Ernahrung,'  Zierassen's  Handhiichder  Hygiene,  1882. 

•  Zeits.  fur  Biologic,  vol.  vii.  1871. 


FOOD  421 

'(33'8  oz.)  of  peas  15  per  cent,  is  passed  out  in  the  feces  ;  but  with  GOO 
grammes  (21  oz.)  only  10  per  cent,  is  lost.^ 

Fats  when  taken  in  as  food  are  acted  upon  by  the  bile  and  pancreatic  juice 
in  the  small  intestines  ;  for  the  most  part  they  are  emulsified  and  absorbed 
by  the  mucous  membrane  direct  (probably  by  means  of  the  epithelial  cells 
and  the  leucocytes),  but  they  are  also  in  part  split  up  into  fatty  acids  and 
glycerine,  the  acids  uniting  with  the  alkalies  present  to  form  soaps  which  are 
absorbed.  An  excess  of  fat  in  the  diet  is  passed  off  in  the  faeces,  and  may 
lead  to  great  digestive  disturbance  by  being  split  up  into  fatty  acids  by  means 
of  bacteria.  Nothing  very  definite  can  be  stated  as  to  what  is  an  excess  of 
fat  in  a  diet ;  what  is  excess  for  one  individual  is  readily  digested  by  another, 
the  labourer  eats  an  amount  of  bacon  fat  which  would  nauseate  and  disturb 
'the  digestion  of  another  person  not  doing  so  much  work. 

Bertha's  experiments  (quoted  by  Parkes)  show  that  30  grammes  of 
animal  oil  added  to  the  ordinary  diet  were  absorbed  ;  but  with  increasing 
quantities  less  was  absorbed,  and  if  60  grammes  were  continued  in  the 
<daily  diet  for  some  time,  50  grammes  passed  away  by  the  intestine. 

Animal  fats  are  more  digestible  than  vegetable,  and  it  is  from  animal 
food  and  products  that  the  fats  of  a  diet  are  derived. 

The  reaction  of  food  is  also  an  important  point.  As  a  rule  it  is  slightly 
.alkaline,  and  this  stimulates  the  flow  of  the  gastric  juice.  If  too  alkaline,  it 
will  tend  to  neutraUse  the  acid  in  the  stomach,  and  thus  to  Innder  digestion. 
The  usual  mistake  is,  however,  that  the  food  is  too  acid.  The  excess  of 
acidity  is  usually  due  to  the  vegetable  acids,  vinegar,  lactic,  tartaric,  or  citric 
acid.  The  excess  of  these  acids,  especially  when  a  large  amount  of  carbo- 
hydrates exists  in  the  food,  tends  to  diminish  digestion  and  absorption  of  the 
food,  and  will  if  persisted  in  lead  to  dyspepsia. 

There  are  other  considerations  with  regard  to  the  digestion  of  food  which 
may  be  briefly  summed  up.  Sleep  diminishes  digestion,  and,  therefore, 
food  ought  not  to  be  taken  just  before  going  to  sleep.  Food  taken  too  often 
also  tends  to  diminish  the  activity  of  the  digestive  juices,  and  gives  no  rest 
to  the  ahmentary  tract.  According  to  Eanke,  laborious  ivorh  diminishes 
digestion  ;  but  Forster  considers  that  it  has  no  great  influence  on  it.  The 
eflect  of  work  on  digestion  probably,  however,  differs  in  the  labouring  man 
-and  in  the  well-to-do. 


3.  Preparation  and  Cooking  op  Food 

Civilised  man  requires  the  majority  of  articles  of  food  to  be  prepared  and 
to  be  cooked.  And  the  higher  the  civilisation,  the  more  is  the  food  elaborated 
:in  its  preparation,  and  the  more  complicated  the  process  of  cooking. 

1.  Preparation  of  Food 

This  is  necessary  with  those  foods  which  contain  a  large  proportion  of 
indigestible  matter.  Thus  the  grain  of  the  wheat,  containing  internally  the 
starch  and  proteid  food,  is  separated  from  its  covering,  which,  although  rich 
in  salts,  contains  much  indigestible  cellulose.  The  starch  and  proteid  are  also 
subjected  to  a  process  of  grinding,  and  finally  are  manufactured  into  bread, 
which  may  be  considered  as  a  partially  digested  food  (see  sub-section  Bread). 
The  removal  of  the  grain-covering  and  the  grinding  of  the  grain-contents  and 
the  making  of  bread  are  all  processes  which  enable  the  digestive  organs 
1)0  obtain  the  greatest  amount  of  nutriment  from  the  wheat-graio,  a  gain 
*  Zeits.  fur  Biologic,  vol.  xvi.,  1880. 


422  HYGIENE 

which  more  than  compensates  for  the  loss  of  salts  contained  in  the  grain- 
covering. 

Other  cereals  are  also  prepared  and  made  into  flours  with  the  object  of 
removing  most  of  the  cellulose.  The  rougher  parts,  too,  of  ordinary  vege- 
tables are  also  removed  for  a  similar  reason.  Animal  foods  do  not  require 
so  much  preparation  as  vegetable— the  removal  of  tendon  from  meat  is  the 
chief  point  to  be  attended  to. 

2.  Effect  of  Cooking 

The  general  effect  of  cooking  is  to  increase  the  digestibility  of  food.  This 
is  more  marked  in  the  case  of  vegetable  food  than  in  that  of  animal.  The 
cooking  also  of  animal  food  especially  develops  '  flavours  '  in  the  food;  which 
is  an  important  point,  since  tasteless  food  cannot  for  long  be  eaten.  Flavour- 
ing agents  are  thus  often  added  to  increase  the  savouriness  of  food  (see  Food- 
Accessories).  Another  result  of  cooking  food  is  the  advantage  of  taking  food 
hot ;  cold  food  has  to  be  raised  to  the  internal  temperature  of  the  body,  and 
thus  when  food  is  hot  less  heat  is  abstracted  from  the  surrounding  parts. 

Cooking  is  also  a  prophylactic  measure.  The  temperature  to  which  well- 
cooked  food  is  exposed  is  sufficient  to  destroy  the  numerous  parasites  which 
may  be  present  in  meat,  such  as  the  cysticerci  of  tapeworms,  and  other  worms, 
and  to  some  extent  to  destroy  any  bacteria  present.  A  much  higher  and  more 
prolonged  temperature  is  necessary  to  completely  destroy  the  micro-organ- 
isms present  in  food,  as  the  presence  of  numerous  bacteria  in  the  digestive 
tract  testifies. 

Vegetables,  such  as  peas,  beans,  &c.,  take  up  during  the  process  of  cooking 
a  large  percentage  of  water  (see  Table,  p.  423).  They  lose  a  certain  proportion 
of  salts,  which  escapes,  if  they  are  boiled  in  much  water.  They  are  best 
cooked,  therefore,  with  a  minimum  of  water,  some  fat  and  salt  being  added 
dming  the  process.  The  chief  effect  on  the  organic  foodstuffs  in  the  cooking 
of  vegetable  food  is  that  part  of  the  proteids  (the  globulins  and  albumins)  is 
coagulated  by  the  heat  to  which  they  are  subjected,  the  remainder  of 
the  proteids  ('legumiu,'  albumose)  being  imaffected  by  the  heat,  while  the 
starch  undergoes  a  complete  change.  Whether  the  coagulated  proteids  are 
more  digestible  than  the  uncoagulated  is  not  at  present  certain  ;  the  heating, 
however,  certainly  renders  them  less  liable  to  be  decomposed  by  the  bacteria 
constantly  found  in  the  digestive  tract.  The  starch-grain  is  in  the  uncooked 
state  hard  and  not  readily  affected  by  the  digestive  juices.  This  is  chiefly 
due  to  the  fact  that  the  grain  is  composed  of  starch  (granulose)  and  a  Httle 
erythrogranulose,  which  are  both  enclosed  in  cellulose  coverings.  The 
efi'ect  of  moist  heat  is  to  burst  the  coats  of  cellulose,  so  that  the  grain  swells 
and  the  starch  is  practically  set  free.  By  boiling,  the  starch  is  converted 
partly  into  so-called  '  soluble  '  starch,  which,  although  of  the  same  chemical 
composition  as  natural  starch,  is  more  readily  acted  upon  by  the  ferments  of 
the  saliva  and  pancreatic  juice.  The  process  of  the  manufacture  of  bread 
must  be  considered  as  a  partial  artificial  digestion,  since  some  of  the  starch 
of  the  flour  is  transformed  into  dextrine  and  maltose,  the  gluten  being: 
semi-coagulated. 

Animal  food  is  as  well  digested  artificially  in  the  fresh  state  as  when 
cooked.  But  cooking  is  necessary,  as  it  diminishes  the  time  of  mastication 
and  increases  the  savouriness  of  the  food.  Unlike  vegetable  food,  animal 
food  loses  instead  of  gains  weight  during  cooking.  The  loss  is  chiefly  water, 
but  is  also  due  to  some  fat,  salts,  and  extractives.  The  following  table  showa- 
the  proportional  loss  or  gain  in  both  kinds  of  food  : — 


FOOD 


423 


Table  showing  Amount  of  Water  in  Foods  before  and  after  Cooking  (Furster) 


Fresh  Foods 


Beef  (Wolff) 


Percentage 
75 


Veal  (Wolff ) 78 

Wheaten  flour 12-14 

Peas li 


Potatoes 
Cabbage 


75 

87 


Cooked 


rernentage 
.  55-69 
.  56-63 
.  60-64 
.  36-40 


Boiled  .... 
Boast  .... 
Boast  .... 
Bread       .... 

Mashed  peas 68-78 

Pea-soup 90 

Mashed  potatoes       ....        78 

Potato  soup 91 

85-90 


As  regards  other  a,nimal  foods,  mutton  loses  in  weight  rather  more  than 
beef  during  cooking  (Letheby). 

Loss  in  Percentage  of  Weiglit  in  Meat  during  Cooking 


- 

Boiling 

Baking 

Boasting 

Beef         ..... 
Mutton 

20 

20 

29 
31 

31 
35 

In  all  forms  of  cooking  large  pieces  of  meat,  the  first  object  is  to  rapidly 
coagulate  the  external  parts,  so  that  during  cooking  the  juice  of  the  meat 
should  be  retained  as  far  as  possible.  After  the  coagulation  of  the  external 
parts,  the  process  of  cooking  ought  to  be  conducted  at  a  low  temperature, 
not  exceeding  160°  F.  (about  71°  C.)  Thus,  in  boiling,  the  meat  ought  to  be 
steeped  for  five  minutes  in  boiling  water ;  in  roasting,  the  joint  must  be 
exposed  quite  close  to  the  fire  at  first  till  the  outer  parts  are  hard,  when  it 
can  be  removed  farther  off.  The  reason  why  meat  should  be  cooked  at  a 
temperature  not  exceeding  70°  C.  is  that  most  of  the  proteid  matter  of  the 
meat  coagulates  between  65°  and  75°  C. ;  the  object  is  to  leave  some  of  the 
proteid  in  a  semi-coagulated  state  ;  but  by  increasing  the  heat  over  70°  C. 
up  to  the  boiling-point  (100°  C.)  the  proteid  matters  are  not  only  completely 
solidified,  but  become,  from  their  hardness,  indigestible.  Over-heating  is, 
therefore,  to  be  avoided ;  and  the  slower  the  cooking,  the  better  the  result. 
In  meat  the  chief  proteid  is  the  myosin  of  the  muscle  fibre ;  there  is  also 
the  serum  of  the  blood  in  the  blood-vessels  and  the  fibrin  of  the  clot  with  the 
hemoglobin.  The  myosin  is  soft  just  after  death,  but  coagulates  soon  after- 
wards, sarcolactic  acid  being  developed  as  well.  This  coagulation  is  called 
rigor  mortis.  After  a  time  rigor  mortis  passes  off  and  the  myosin  becomes 
softer  again ;  the  meat  is  then  ready  for  cooking.  In  hunted  and  over- 
driven animals,  rigor  mortis  is  early  in  appearing. 

In  between  the  muscle  fibres  is  connective  tissue,  the  collagen  of  which, 
during  cooking,  yields  gelatine.  The  dissolved  gelatine  partly  escapes  with 
the  melted  fat  out  of  the  meat,  and  the  muscle  fibres  are  thus  loosened, 
and  rendered  more  easy  to  chew.  There  is  also  a  great  loss  of  salts — more 
in  boiling  than  in  roasting  meat. 

To  sum  up  the  changes  that  occur  during  the  cooking  of  animal  food : 
there  is  a  gradual  and  not  complete  coagulation  of  the  proteid  constituents 
of  the  food,  the  formation  of  gelatine  chiefiy  from  the  connective  tissues, 
causing  partial  disintegration  of  the  tissue,  and  finally  a  loss  of  salts. 

Soups  and  broths  are  best  considered  as  food-accessories,  and  their  effect 
will  be  considered  under  that  head.  Simple  soups  contain  some  of  the  salts 
of  meat  (potassium  and  phosphates)  with  added  sodium  chloride,  and  the 


424  HYGIENE 

extractives  of  meat,  together  with  the  aromatic  products  (sometimes  called 
osmazome).  The  chief  proteid  they  contain  is  gelatine  derived  from  the 
connective  tissue  of  the  meat.  The  aromatic  products  differ  as  to  whether  the 
broth  is  made  from  beef,  mutton,  chicken,  &c.  Broths  often  have  vegetables 
added  to  them,  potatoes,  carrots,  &c. 

For  the  action  of  soups  and  broths  see  Food-accessokies  (p.  477). 

The  Diseases  caused  by  Food 

In  the  preceding  pages  the  data  on  which  food  must  be  taken  have  been 
given.  It  has  been  shown  that  not  only  must  there  be  a  certain  amount  of 
foodstuff's  present  in  the  food,  but  the  food  must  be  in  a  digestible  form  and 
must  be  properly  cooked.  If  these  points  are  not  attended  to  in  a  dietary, 
the  food  ingested  does  not  perform  its  functions  ;  it  does  not  support  the 
nitrogen  equihbrium,  nor  does  it  supply  sufficient  material  for  the  energy 
required  by  the  body.  The  evils  that  may  arise  from  indigestible  food  have 
already  been  discussed  (Digestibility  op  Food,  p.  420),  as  well  as  those 
arising  from  bad  cooking.  There  remain  for  consideration  the  bad  effects 
which  arise  from  an  excess  of  food,  from  a  diminution  of  it,  or  from  diseases 
communicated  by  it.  This  last  point  will  be  left  for  discussion  after  each 
separate  article  of  food  has  been  treated. 

Effect  of  an  Excess  of  Food 

The  effect  of  over-feeding  is  more  often  noticed  in  the  well-to-do  than  in 
the  poorer  classes.  In  many  cases  it  is  simply  a  habit,  but  one  which  leads 
to  serious  consequences.  A  very  large  excess  of  food,  as  we  have  seen,  throws 
great  work  on  the  digestive  system,  so  that  the  digestive  juices  cease  to 
secrete  and  the  peristalsis  of  the  stomach  and  intestines  fails  to  propel  the 
food  along.  The  result  of  this  is  a  putrefying  and  fermenting  mass  in  the 
intestines,  which  may  be  large  in  amomit  and  may  necessitate  removal  by 
artificial  means  ;  or  it  may  be  discharged  by  setting  up  diarrhoea.  Although 
not  commonly  of  such  a  severe  type,  the  symptoms  of  an  excess  of  food  are 
often  present  in  large  eaters.  Excess  of  food,  therefore,  primarily  causes 
mdigestio7i,  with  diminished  absorption.  But  more  food  than  necessary  may 
be  absorbed,  so  that  the  body  gains  weight  considerably,  as  Voit  has  shown, 
the  gain  being  chiefly  in  the  form  of  fat.  An  excess  of  proteid  food  (chiefly 
of  animal  food)  throws,  as  we  have  seen,  great  work  on  the  nitrogenous 
tissues,  so  that  disorders  of  the  hver  and  muscles  follow  ;  it  is  considered,  too, 
as  one  of  the  factors  in  the  production  of  gout.  And  if  proteids  are  taken  in 
excess  while  the  fat  and  carbohydrate  of  the  diet  are  in  small  proportion,  the 
body  loses  in  weight,  and  this  loss  is  chiefly  fat.  For  although  it  has  been 
clearly  demonstrated  that  proteids  are  to  some  extent  a  som'ce  of  fat  in  the 
body,  they  cannot  replace  the  fat  in  the  food  ;  so  that  when  a  diet  is  greatly 
deficient  in  fat  and  carbohydrate,  the  body  draws  on  its  own  store  of  fat, 
which  then  gradually  disappears.  These  facts  are  the  explanation  of  the 
Banting  cure  of  obesity.  The  amount  of  stored-up  fat  which  is  destroyed 
depends,  therefore,  on  the  quantity  of  fat  in  the  food  and  that  in  the  body. 

Other  facts  are  important  in  the  consideration  of  the  effect  of  an  excess  of 
proteid  food  in  the  body.  These  are  that  the  decomposition  of  proteid  in  the 
body  is  proportional  to  the  intake,  even  if  large  quantities  be  taken  ;  in  other 
words,  the  excretion  of  urea  augments  with  the  increase  of  proteid  in  the 
food.  As  a  corollary  of  this,  it  may  be  stated  that  the  amount  of  proteid 
taken  in  the  body  is  proportional  to  the  oxygen  absorbed  in  the  lungs ;  for  if 


FOOD  425 

there  is  aiii  excess  of  proteid,  there  must  be  an  excess  of  oxygen  (above  the 
normal)  to  oxidise  it.^ 

An  excess  of  fats  and  starches  in  the  dietary  tends  to  produce  corpulence 
and  dyspepsia.  As  we  have  seen,  both  the  fat  of  the  food  and  the  carbo- 
hydrates lead  to  the  deposition  of  fat  in  the  body.  The  excess  of  fat  and 
starch  also  partly  passes  away  in  the  faeces,  or  after  absorption  some  of  the 
starch  may  pass  away  in  the  urine  as  dextrose. 

But  little  is  known  of  the  effect  on  the  body  of  an  excess  of  mineral  food. 
Two  points  may,  however,  be  mentioned.  An  excess  of  potassium  salts  in  the 
food  withdraws  sodium  and  chlorine  from  the  tissues  and  causes  an  increased 
excretion  of  sodium  chloride.  This  occurs  when  vegetable  food  forms  the 
chief  part  of  a  diet,  since  such  food  contains  a  large  quantity  of  potassium 
phosphates.  The  necessity  of  sodium  chloride  for  vegetable  feeders  is  thus 
•explained.^ 

An  excess  of  water  in  the  food  is  not  stored  up  in  the  body,  but  is  excreted 
by  the  urine.  The  excess  over  the  normal  does  not  simply  filter  through  the 
body,  but  it  has  an  effect  on  the  tissues.  Thus  it  tends  to  produce  oxidation 
of  the  proteid  of  the  body,  and  a  great  excess  may  even  lead  to  hypertrophy 
of  the  heart  and  fatty  degeneration  (Buhl,  quoted  by  Forster). 

Sodium  chloride  in  excess  increases  the  metamorphosis  of  proteids  in  the 
body.^ 

Effect  of  Diminution  of  Food 

The  complete  withdrawal  of  food,  or  an  insufficient  supply  of  it,  leads  to 
■the  phenomena  of  starvation,  with  symptoms  more  or  less  intense.  The 
-complete  withdrawal  of  food  leads  to  rapid  wasting  of  the  body,  dryness  of 
the  mucous  membranes,  weak  action  of  the  heart  and  of  the  respiratory 
system,  and  on  the  part  of  the  nervous  system  to  restlessness  and  delirium, 
ending  in  coma.  A  vigorous  adult  dies  when  he  loses  two-fifths  of  his  body- 
weight  ;  the  young  succumb  sooner,*  More  important,  however,  from  the 
point  of  view  of  hygiene,  than  the  effect  of  complete  withdrawal  of  food  is  the 
effect  of  an  insufficient  supply.  In  public  institutions,  prisons,  workhouses, 
orphan  asylums,  &c.,  and  in  the  army  and  navy,  where  there  is  a  prescribed 
diet,  it  is  evident  that  an  inadequate  supply  of  food  may  be  fraught  with 
disastrous  consequences  to  large  bodies  of  individuals  ;  and  especially  is  this 
so  with  the  young,  for  inadequate  nourishment  during  the  growing  period 
leaves  its  stamp  on  the  organism  for  Hfe.  A  general  diminution  of  all  the 
foodstuffs  in  a  dietary,  if  continued  for  some  time,  leads  to  a  general  weaken- 
ing of  the  body,  and  so  exposes  the  individual  to  greater  danger  from  the 
effects  of  specific  fevers  and  disorders  and  from  the  effects  of  cold;  and 
especially  is  this  so  if  work  has  to  be  done  on  an  insufficient  diet,  for  in 
this  case  work  is  added  to  the  balance  against  the  individual. 

In  the  previous  pages  it  has  been  pointed  out  in  what  respects  the  diets 
of  communities  living  together  are  deficient.  Proteids  and  fats,  especially 
•the  latter,  are  the  two  chief  foodstuffs  deficient  in  their  dietaries ;  and  by 
an  increase  of  the  fats  of  the  diet,  the  health  of  the  communities  is  undoubt- 
edly greatly  improved.  It  has  even  been  considered  that  the  occurrence  of 
scurvy  in  prisoners  may  be  connected  with  a  deficiency  of  animal  fat  in  the 

*  Some  of  the  absorbed  proteid  may  not  be  oxidised,  and  thus  pass  out  of  the  body  in 
;the  urine ;  excess  of  proteid  food  is  thus  considered  one  of  the  causes  of  functiotial 
.albuminuria. 

2  See  Bunge,  Zeits.  f.  Biol.  Bd.  ix.  1873,  p.  104  ;  ibid.  Bd.  x.  1874,  p.  111. 
^  Voit,  Einfluss  des  Eochsalzes  u.s.w.  auf  d.  Stoffwechsel.    Miinchen,  1860. 

*  For  fuller  details  see  works  on  physiology. 


420  HYGIENE 

diet.'  The  most  that  can  be  said  of  this,  however,  is  that  it  may  be  a  part 
of  the  history  of  scurvy. 

The  eflects  of  a  diminution  of  proteids  have  ah-eady  been  considered,  as 
well  as  that  of  a  diminution  of  fats  and  carbohydrates  in  the  diet ;  we  may 
repeat  that  a  diminution  of  nitrogenous  food  leads  to  increased  oxidation  of 
the  body  proteids,  i.e.  to  a  loss  from  the  body,  in  order  that  the  nitrogea 
equihbrium  may  be  maintained.  Fats  and  carbohydrates  are,  as  has  been 
shown,  eminently  proteid- sparing  foods  ;  therefore  the  diminution  of  them  in 
the  diet  leads  either  to  increased  ingestion  of  proteids  in  the  food  or  to  an 
increased  destruction  of  proteids  in  the  body. 

With  regard  to  mineral  foods ,  the  effect  of  this  diminution  in  the  diet  has 
been  already  for  the  most  part  discussed  in  treating  of  the  necessity  of  the 
earthy  phosphates  for  the  growing  organism,  and  that  of  sodium  chloride  to 
vegetable  feeders.  The  salts  of  the  body  exist  in  two  forms,  the  body-salts 
or  those  united  with  the  tissues,  and  the  floating  salts  or  those  dissolved  in 
the  fluids  (Forster).  These  bear  a  certain  proportion  to  each  other  ;  and  if 
the  floating  salts  are  not  replaced  by  the  salts  of  the  food,  the  body- salts  are 
more  or  less  withdrawn  from  the  tissues.  In  scurvy,  for  example,  there  is. 
a  diminution  of  potassium  salts  in  the  body  ;  and  this  is  considered  one  of 
the  factors  of  the  disease.  Forster  (quoting  Felix)  says  that  there  may  also 
be  excessive  excretion  of  potassium  salts  in  the  urine  when  salt-junk  is  eaten. 
Ammonium  chloride  (and  probably  sodium  chloride)  increases  the  excretion 
of  potassium  salts  :  hence  the  effect  of  salt-junk  may  possibly  be  explained. 
On  the  other  hand,  the  beneficial  effect  of  lime-juice  in  scurvy  has  led 
some  to  consider  that  there  is  a  connection  between  the  disease  and  the 
ingestion  of  vegetable  acids  (citric,  tartaric,  &c.),  although  it  has  been  shown 
that  these  acids  of  themselves  have  no  curative  powers  in  scurvy. 

Diminution  in  the  amount  of  wate7'  leads  to  storage  of  water  in  the  body, 
especially  in  the  muscles,  and  this,  like  an  excessive  ingestion  of  water, 
leads  to  the  destruction  of  body-proteid.  The  tissues  in  this  watery  condi- 
tion are  deficient  in  activity,  and  this  condition  may,  according  to  Forster,  be- 
connected  with  the  predisposition  of  the  lower  classes  to  infectious  diseases, 
and  in  general  with  a  diminished  resistance  against  disease.  Scurvy  is 
specially  considered  after  Lemon-juice  (p.  474). 

ABTICLES   OF  FOOD 
Anibial  Foods 

Articles  of  diet  derived  from  the  various  parts  of  animals  are  important 
in  several  ways.  First,  they  are  pre-eminently  proteid  foods.  In  them, 
speaking  generally,  the  proteids  exist  in  large  proportion  ;  are,  as  a  rule,  easily 
digested ;  and  are  not  mixed  with  substances  (such  as  cellulose)  which  inter- 
fere with  digestion. 

Second,  most  of  the  fat  taken  as  food  is  derived  from  animal  products. 
The  fat  forms  part  of  the  various  kinds  of  edible  flesh,  of  milk,  and  is  sepa- 
rated as  butter,  suet,  lard,  &c.  These  fats  are  more  easily  digested  and  more 
readily  assimilated  than  vegetable  fats. 

Third,  animal  foods  are  one  of  the  sources  of  sodium  chloride,  which  ia 
necessary  for  existence.  Thus,  although  the  solid  tissues  themselves  con- 
tain an  excess  of  phosphates  and  of  potassium  over  chlorides  and  sodium,. 
yet  in  the  liquids  which  bathe  the  solid  tissues,  e.g.  the  liquid  round  the- 
muse  alar  fibres  or  the  liquid  part  of  the  blood  in  the  muscle,  and  in  fact  iiL 

'  Konig,  op.  cit.  Bd.  i.  p.  171. 


FOOD 


427 


all  animal  liquids,  this  relation  is  reversed.  The  fact  has  already  been  referred 
to,  that  with  vegetable  feeders  common  salt  is  a  necessity  which  has  to  be  added 
to  the  food,  whereas  with  animal  feeders  it  is  not  so  imperatively  called  for. 

Fourth,  a  great  distinction  between  certain  vegetable  foods  and  animal 
foods  is  that  the  latter  do  not  possess  to  any  degree  an  antiscorbutic  power. 
It  is  true  that  in  the  '  Eira  '  Arctic  Expedition,  fresh  meat  (walrus)  was  found 
to  prevent  an  outbreak  of  scurvy  in  the  men  ;  but,  as  a  rule,  it  may  be  said 
that  fresh  meat  is  not  to  any  extent  antiscorbutic. 

It  may  agam  be  pointed  out  that  cooking  is  all-  important  for  animal  foods, 
not  only  to  render  the  food  more  digestible,  but  also  to  destroy  parasites 
(see  Cooking  of  Food,  p.  421) ;  and  this  remark  applies  to  the  boiling  of 
milk  as  well  as  to  the  cooking  of  the  solid  animal  foods. 

Milk  (and  to  some  extent  liver)  is  the  only  animal  food  which  may  be 
considered  a  carbohydrate  food. 

MILK  AND   MILK-PRODUCTS 

The  chief  forms  of  milk  and  milk-products  may  be  arranged  as  follows  :  — 

1.  Milk  from  the  cow,  buffalo,  ass,  goat,  and  mare  ;  human  milk. 

2.  Milfc-products. 

Unaltered  from  natural  milk  : — 

a.  Skimmed  milk,  including  various  forms. 
h.  Cream. 

c.  Butter. 

d.  Condensed  milks. 

Altered  from  natural  milk  by  decomposition  or  fermentation : — 

e.  Cheese. 

/.  Koumiss  and  Kephir. 

3.  Prepared  milk-foods  for  infants  and  invalids. 


Composition  of  diffebent  Milks 

All  forms  of  milk  are  emulsions  of  fat  containing  proteids,  carbohj'drates, 
and  salts  in  solution  in  water.  In  the  following  table  (summarised  from 
Konig)  the  average  composition  of  milks  is  given  in  percentages,  i.e.  in 
100  cubic  centimetres  is  contained  the  dried  weight  of  foodstuffs  in  grammes 
stated. 

Composition  of  Milks  in  100  parts  (average  of  many  analyses) 


- 

Sp.  gr. 

Total 
solids 

Pro 
Casein 

;eid 
Albumin 

Fat 

Lactose 

Salts 

Water 

Proportion 
of  nit.  to 
non-nit.  as 

Mare's  . 
Ass's 
Human  . 
Cow's    . 
Goat's   . 
Buffalo's 

1035 
1023-1035 
1027 
103ii 
1032 
1032 

9-22 
10-36 
12-59 
12-83 
14-29 
18-59 

1-24 

0-75 

1-21 
1-64 
3-78 
3-69 
4-78 
7-47 

5-67 
5-99 
6-21 
4-88 
4-46 
4-15 

0-35 
0-51 
0-31 
0-71 
0-76 
0-87 

90-78 
89-64 
87-41 
87-17 
85-71 
81-41 

1  :  3-4 
1  :3-4 
1:4-4 
1  :2-5 
1:2-0 
1:1-9 

1-99 
0-67    1    1-55 

2-22 
1-03    1    1-26 

2-29 
3-02    1    0-53 

3-55 
3-20    1    1-09 

4-29 
5-85    1    0-25 

6-10 

428  HYGIENE 

The  kinds  of  milk  important  from  the  point  of  view  as  food  to  man  are 
human  milk  and  cow's.  They  differ  in  the  following  particulars  :  as  regards 
the  proteids,  human  milk  differs  from  cow's  in  havini^  less  casein  but  more 
albumin ;  the  fat  is  about  the  same  in  both  kinds,  there  is  more  sugar  in 
human  than  in  cow's  milk,  but  less  salts. 

The  salts  of  milk  are  composed  of  all  the  constituents  necessary  to  the 
growing  organism :  calcium,  sodium,  potassium,  chlorides,  phosphates,  and 
iron.  As  in  most  foods,  the  potassium  and  phosphates  are  in  excess.  The 
calcium  phosphate  present  aids  in  the  solution  of  the  casein.  Besides  the 
mineral  salts,  there  are  organic  compounds,  such  as  urea,  creatin,  sarkin, 
ttc,  which  are  included  under  the  term  extractives. 

Percentage  of  Salts  in  the  Ash  of  Human  Milh.^ 

NaCl 10-73 

KCl 26-33 

KHO 21-44 

Ca 18-78 

Mg 0-87 

V.O, 19-0 

Fe.,P.,0=, 0-21 

HoSO^ 2-64 

Silica Trace 

Variations  in  the  Composition  of  Cow's  Milk 

1.  Time  after  Calving. — The  first  milk,  or  colostrum,  varies  greatly  from 
that  subsequently  secreted.  It  contains,  like  the  colostrum  of  human  milk,  a 
large  quantity  of  serum-albumin,  a  larger  quantity  than  normal  of  casein  ; 
while  the  lactose  is  diminished.  The  mean  of  many  analyses  given  by  Konig 
is  74-67  percent,  of  water  ;  4-04  of  casein,  13-6  of  albumin  ;  3*59  of  fat,  2-67 
of  lactose,  and  1*67  per  cent,  of  salts. 

After  the  colostrum,  the  milk  varies  shghtly  in  quaHty,  being  at  first 
mixed  with  the  colostrum. 

Up  to  the  second  month  after  delivery,  the  casein  and  fat  are  increased. 
From  the  tenth  to  the  twenty-fourth  month  the  casein  diminishes,  while  the 
fat  becomes  less  from  the  fifth  to  the  sixth  month,  and  the  tenth  to  the 
eleventh.  The  sugar  is  diminished  during  the  first  month,  but  increases  from 
the  eighth  to  the  tenth  month.  The  salts  increase  up  to  the  fifth  month,  after 
"which  they  steadily  diminish.^ 

2.  The  Race  of  the  Goto. — Some  milks  are  rich  in  fat,  others  in  casein. 

3.  The  Kind  of  Feeding. — Fodder  rich  in  carbohydrates,  such  as  beet, 
carrot,  &c.,  causes  an  increase  of  the  amount  of  sugar  in  the  milk.  An  in- 
crease of  proteids  in  the  diet  causes  an  increase  of  the  casein,  while  the  fat  is 
not  much  influenced. 

The  age  of  the  cow  and  the  number  of  pregnancies  also  affect  the  compo- 
sition of  the  milk. 

Milk  as  an  Abticle  of  Diet 

Milk  is  the  chief  diet  for  children  up  to  the  age  of  eighteen  months  or  two 
years  :  its  value  has  already  been  partly  pointed  out  (p.  410).  It  is  almost 
completely  digested  in  the  iatestiaes :    when  exclusively  used  for  adults,  it 

*  The  composition  of  the  ash  of  cow's  milk  is  similar. 
*  Landois  and  Stirling's  Physiology,  3rd  ed.  p.  347. 


FOOD 


42? 


leads  to  constipation.  When  digested  either  by  pepsin  or  the  pancreatic  juice, 
milk  clots,  the  casein  being  precipitated  in  large  curds.  This  is  the  first 
stage  of  digestion ;  the  curds  are  then  changed  into  albumoses  and  peptones  hy 
the  ferments,  a  bitter  substance  being  formed  which  makes  the  peptonised 
milk  unpleasant  to  the  taste. 

For  infants,  human  milk  contains  the  nitrogenous  and  the  non-nitro- 
genous organic  foodstuffs  in  the  right  proportion,  viz.  1  :  4*4  ;  and  so  does 
mare's  or  ass's  milk.  But  in  cow's  milk  the  proportion  is  1  :  2*5,  and 
therefore  cow's  milk  is  not  a  perfect  food  by  itself.  If  the  non-nitrogenous 
organic  foodstuffs  are  increased,  as  by  adding  sugar  or  arrowroot  to  the  milk,, 
it  then  becomes  a  very  important  food.  Such  additions  are  made  for  young 
children  and  in  the  dietary  of  adults. 

As  cow's  milk  has  often  to  be  substituted  for  human  milk  in  the  rearing 
of  children,  it  is  important  in  many  instances  to  artificially  bring  the  compo- 
sition of  the  milk  to  that  of  human  milk.  This  is  done  in  the  following 
manner  :  the  cream  is  separated  from  a  pint  of  milk,  and  the  casein  of  one- 
half  of  the  skimmed  milk  coagulated  with  a  small  quantity  of  rennet  and 
strained  off.  To  this  whey  the  cream  which  has  been  removed  and  the 
rest  of  the  skimmed  milk  is  added.  The  composition  of  this  artificial 
human  milk  varies  :  it  contains  on  the  average  a  little  over  2  per  cent,  of 
proteid,  4*5  per  cent,  of  fat,  5  per  cent,  of  lactose,  and  0'6  per  cent,  of  salts. 
Li  feeding  infants,  the  cow's  milk  has  to  be  diluted ;  for,  containing  much, 
casein,  this  forms  large  clots  in  the  stomach,  which  cause  indigestion. 
Dilution  diminishes  the  size  of  the  clots  of  casein,  and  in  many  instances 
this  is  suflficient ;  lime-water  or  barley-water  added  is  also  beneficial  in  some 
cases.  After  dilution,  the  addition  of  sugar  to  the  cow's  milk  is  necessary  to 
bring  it  nearer  to  the  standard  of  human  milk.  Spiegelberg  ^  says  that  during 
the  first  three  or  four  weeks  of  life  two  parts  of  water  must  be  added  to 
one  part  of  milk ;  after  the  third  and  fourth  months,  more  milk  may  be 
given,  till  from  the  fifth  and  sixth  months  the  child  may  have  undiluted, 
milk.  The  milk  has  often  to  be  more  diluted  than  this.  To  each  litre  of 
diluted  milk  thirty  grammes  of  milk-sugar  must  be  added. 

Percentage  Composition  of  diluted  Milk  and  added  Lactose 


- 

Proteid 

Fat 

Sugar 

Salts 

Water 

Proportion 
of  nit.  to 
non-nit.  as 

Cow's  milk  with  equal  parts  of  water     . 
Cow's  milk  with  two  parts  of  water 

1-77 
1-18 

1-85 
1-23 

5-44 
4-68 

0-35 
0-23 

92-73 
90-59 

1  :4 

1  :4-8 

During  the  first  half-year  a  child  weighing  5  to  6  kilogrammes  consumes 
1  to  2  litres  of  mother's  milk  daily,  i.e.  in  a  litre  nearly  30  grammes  of 
proteid,  39  grammes  of  fat,  62  grammes  of  sugar,  and  3  grammes  of 
salts.  To  obtain  a  similar  amount  of  foodstuffs,  it  would  require  to  take  daily 
3  litres  of  milk  diluted  with  2  parts  of  water  ;  it  would,  however,  be  then  receiv- 
ing nearly  140  grammes  of  lactose. 

Ass's  milk  is  nearest  in  composition  to  human  milk,  and  is  sometimes  used 
as  a  substitute :  its  chief  deficiency  is  in  the  amount  of  fat.  Mare's  milk 
contains  less  proteids  and  fat  than  ass's  milk  ;  while  goat's  milk  and  buffalo's 
are  very  rich  in  fat,  the  former  having  a  pecuUar  smell. 

^  Midwifery,  New  Syd.  Soc.'s  Trans,  vol.  i.  1887,  p.  829. 


430  HYGIENE 

One  litre  of  cow's  milk  (35  ounces)  contains — 

35-0  grammes  of  proteid 
36-9  „         fat 

48-8  „         lactose 

7"1  „  Baits 

and  871'7  „         water 

Sucli  a  quantity,  then,  contains  half  the  daily  quantity  of  proteids,  and 
more  than  half  the  daily  quantity  of  fat  necessary  for  a  child  from  six  to 
fifteen  years  of  age. 

An  adult  would  require  5  Htres  (ahout  9  pints)  of  milk  daily  to  obtain  the 
requisite  amount  of  proteids,  180  grammes  ;  and  then  he  would  be  taking  180 
grammes  of  fat,  and  only  240  grammes  of  carbohydrates.  Milk,  being  easily 
digested,  is  a  useful  article  of  diet  in  certain  cases  of  mal-assimilation  of  food 
or  in  old  age. 

Diseases  Caused  by  Milk  and  Milk-peoducts 

1.  Milk  after  standing  for  some  time  becomes  sour  and  coagulates.  This 
effect  is  due  to  the  bacillus  acidi  lactici,  so  named  because  lactic  acid  is  the 
chief  product  of  its  activity,  carbonic  acid  being  at  the  same  time  formed. 
Such  milk  is  a  fruitful  source  of  digestive  trouble  in  infants,  and  is  unfit  for 
food.  It  leads  to  vomiting,  flatulence,  and  diarrhoea.  To  sour  milk  are 
to  be  ascribed  many  of  the  cases  of  infantile  diarrhoea. 

Blue  milk  is  not  common.  The  colouration  is  due  to  the  growth  in  the 
milk  of  the  bacillus  cyanogemis,  which  is  itself  colourless,  but  imparts  a 
blue  colour  to  the  milk,  intensified  if  the  lactic  acid  fermentation  also 
occurs.  The  blue  colour  was  at  one  time  ascribed  to  the  eating  of  cer- 
tain meadow-plants.  Blue  milk  causes  irritation  of  the  stomach  and  in- 
testines, producing  diarrhoea. 

Many  micro-organisms  produce  coagulation  of  milk,  e.g.  the  bacillus 
butyricus  of  butyric  acid  fermentation.  Other  fungi  turn  the  milk  bluish 
black  or  green.  Yelloio  milk  is  due  to  bacterium  synxantlium,  which 
makes  the  milk  first  acid,  then  strongly  alkaline.  Bed  milk  is  due  to  micro- 
coccus inodigiosus  ;  the  change  was  formerly  ascribed  to  disease  of  the  cow. 
Both  the  colouring  matters  of  yellow  and  red  milks  are  related  to  anihne. 
Milk  may  also  become  stringy  or  ropy,  due  to  the  action  of  bacteria. 

2.  Besides  these  visible  changes  in  the  milk,  occurring  after  the  milk 
has  been  drawn,  there  are  others  which  are  present  in  the  milk  when 
drawn. 

a.  Many  substances  are  excreted  in  the  milk  when  given  to  the  mother 
or  taken  in  loith  the  fodder  of  the  animal.  Iodides,  arsenic,  antimony, 
mercury,  carbohc  and  sahcylic  acids,  rhubarb,  and  opium  may  thus  be  present 
in  the  milk  and  affect  the  child.  Castor  oil  also  when  taken  by  the  mother 
acts,  as  is  well  known,  as  an  aperient  to  the  child. 

Turnips,  diseased  potatoes,  and  other  plants  in  the  fodder  of  the  cow  may 
impart  an  unpleasant  aroma  to  the  milk  without  altering  its  efficacy  as  an 
article  of  diet.  But  some  other  kinds  of  fodder  produce  poisonous  milk, 
owing  to  the  excretion  of  poisonous  substances.  For  example,  the  milk  of 
goats  which  have  eaten  colchicum  or  Euphorbiaceous  plants  produces 
poisonous  symptoms,  including  diarrhoea.  The  milk  from  cows  feeding  on 
wort  is  injurious.^  The  Ii7t7(s  toxicodendron  olso  i^roduces  poisonous  milk; 
children  partaking  of  it  suffering  from  weakness,  vomiting,  and  constipation. 

'  Forster,  op.  cit.  p.  159. 


FOOD 


431 


The  plant  also  causes  '  trembles  '  in  the  cows.     The  poison  is  destroyed  by 
boiling  the  milk. 

h.  The  milk  7nay  he  affected  by  the  diseased  condition  of  the  cow.     The 
mammary  gland  of  the  animal  may  be  affected  with  disease  ;   it  may  be 


Fig.  87.  Human  milk  with  colostrum 
corpuscles  {a).     (Carpenter.) 


Fig.  88. — Milk  iu  foot-and-mouth  disease, 
showing  clustered  milk  corpuscles  and 
Isacteria  (early  stage).'- 


Fig.  89. — Milk  in  foot-and-mouth  disease  (late  stage).'- 
1  &  3.  Granular  corpuscles.         2.  Milk  corpuscles.        4  &  5.  Bacteria. 

acutely  inflamed  (acute  mastitis)  or  chronically  (interstitial  mastitis),  or  it 
may  be  tubercular.  Pus  may  then  be  present  in  the  milk  as  well  as  tubercle 
bacilli.  The  analysis  by  Flirstenberg  of  milk  from  a  cow  with  interstitial 
hyperasmia  of  the  mammary  gland  shows  a  varying  composition.     In  one 

'  Figs.  88  and  89  are  taken  from  tlie  Lancet,  vol.  ii.  1869,  p.  590. 


432 


HYGIENE 


animal  the  milk  contained  5-78  per  cent,  of  proteid,  with  only  a  trace  of  fat 
and  lactose  ;  in  another  the  proteid  was  still  higher— 8-89  per  cent.,  while 
the  fat  and  salts  were  increased  and  the  lactose  helow  normal ;  in  a  third  the 
composition  of  the  milk  was  within  the  normal  limits.  In  acute  mastitis 
the  casein,  fat,  and  sugar  were  found  diminished,  while  the  albumin  was 
greatly  increased— 5-3  per  cent.  (Fiirstcnbcrg,  quoted  hy  Konig).^ 

In  foot-and-month  disease  {eczema  epizootica)  the  milk  varies  in  com- 
position greatly,  and  under  the  microscope  pus  and  blood  corpuscles  are 
often  seen  (figs.  88  and  89).  The  following  analyses  (quoted  by  Konig)  show 
this  : — 

Composition  of  Milk  in  Foot-and-Month  Disease 


- 

Water 

Casein 

Albumin 

Fat 

Lactose 

Salts 

Acute  stage    . 

87-70 

3-90 

3-90 

3-81 

-  „',  ^  Lassainne 

During  convalescence    . 

90-60 

2-85 

2-30 

3-02 

On  '2nd  daj'  of  disease  . 

79-90 

—      i    14-38 

5-01 

— 

0-711 

0-21  I  Wynter  Blyth 

On  4tli  day  of  disease    . 

83-85 

3-47 

7-80 

4-67 

On  lith  day  of  disease  . 

83-88 

—      1    11-48 

3-9(5 

— 

0-G8  1 

The  composition  of  the  milk,  therefore,  varies  greatly  ;  the  chief  point  in 
Wynter  Blyth's  analyses  is  the  great  excretion  of  serum-albumin  in  the  milk. 
The  milk  from  cows  suffering  from  foot-and-mouth  disease  may,  according 
to  some,  cause  disease  in  the  human  being,  and  especially  in  the  case  where  the 
udder  of  these  cows  is  in  an  aphthous  condition. ^  The  symptoms  are 
limited  to  the  mouth,  and  consist  in  aphthous  ulceration,  with  hyper^emia 
and  the  formation  of  a  membrane,  and  swollen  tongue  (Parkes).  The  milk 
is  fatal  to  calves  and  to  young  pigs.- 

Tuberculosis  in  cows  {Perlsucht)  affects  the  milk,  and  may  lead  to  the 
same  disease  in  man.  A  distinction  must  be  drawn  between  the  milk  from 
cows  with  tubercular  udders  and  that  from  animals  with  general  tuberculosis 
only,  since,  according  to  Bang,  tubercle  bacilli  are  rare  m  milk  unless  the 
udder  is  tuberculous.  Animals  can  be  given  tuberculosis  by  feeding  them 
with  milk  from  tubercular  cows  (Bollinger).  Boiling  the  milk  is  a  preventive 
measure,  as  the  tubercle  bacilli  are  destroyed  by  heat.  The  composition  of 
the  milk  varies  from  the  normal.  If  the  glands  are  themselves  tubercular 
the  secretion  is  strongly  alkaline.  The  mean  of  three  analyses  by  Storch  ^  of 
milk  taken  at  different  times  from  the  same  cow  is  87'52  per  cent,  of  water, 
5-58  per  cent,  of  proteid,  4-29  of  fat,  1-65  of  lactose,  and  0-96  of  salts. 
Lehmann,  however,  found  in  the  milk  of  a  tubercular  cow  only  a  small  pro- 
portion of  casein  and  fat,  and  Forster  *  in  another  case  found  a  large  quantity 
of  proteid  and  fat,  but  only  1-06  per  cent,  of  lactose — a  result  more  closely 
resembhng  Storch's  analysis. 

The  milk  from  cows  suffering  from  cattle-2)lague  {Binderpcst)  is  altered  in 
composition.  According  to  Monier's  analyses  it  contains  a  large  proportion 
of  casein  (8"2  to  10-12  per  cent.),  a  trace  of  albumin  (0-49  to  0-85  per  cent.), 
a  large  proportion  of  salts  (1*12  to  1"59),  while  in  the  late  stages  of  the  dis- 
ease there  is  a  great  diminution  in  the  amount  of  fat  and  sugar. 

Power  and  Klein  have  described  a  disease  of  cows  which  leads  them  to 
think  that  scarlet  fever  may  be  transmitted  by  the  milk  to  man.  The 
organisms  found  in  scarlet  fever  and  in  the  cow  disease  (at  Hendon)  were 
described  as  identical.^ 

»  Forster,  loc.  cit.  *  Lancet,  vol.  ii.  1869,  p.  590. 

3  Quoted  by  Konig,  op,  cit.  p.  332.  *  Op.  cit.  p.  161. 

*  For  the  controversy  on  this  subject  see  the  medical  journals,  1888-9. 


FOOD 


433 


3.  After  being  drawn  the  milk  may  be  infected,  and  it  is  in  this  -way  that 
milk  has  been  supposed  to  be  the  vehicle  for  the  poisons  of  typhoid  fever 
and  diphtheria  and  many  cases  of  scarlet  fever.  Cases  of  these  diseases 
have  been  present  near  the  dairy,  and  the  milk  has  become  infected  either 
directly  or  by  the  use  of  water  impregnated  with  the  poison. 

One  of  the  best  prophylactics  against  diseases  arising  from  the  use  of  milk 
is  boiling  the  milk ;  this  ought  always  to  be  done  in  summer  and  winter. 

Peeseevation  op  Milk 

Cow's  milk  may  be  preserved  by  boiling,  and  tightly  corking  the  vessel. 
The  preservation  is,  however,  only  temporary.  Antiseptics  may  be  added 
after  boiling,  such  as  salicylic  acid,  boric  acid,  boroglyceride,  sulphurous 
acid.     Of  these  the  most  innocuous  are  boric  acid  and  boroglyceride. 

The  best  forms  of  preserved  milks  are  the  concentrated  forms — the  con- 
densed milks,  with  or  without  the  addition  of  sugar,  and  the  dried  milk. 

In  condensed  milk  without  the  addition  of  sugar  the  preparation  is  sold 
in  tins,  and  the  milk  does  not  keep  for  very  long  after  the  tin  is  opened. 
The  sweetened  condensed  milks  keep  for  a  month  or  longer  after  opening. 

Scherff's  preserved  milk  is  condensed  to  one-half  or  one-third  of  the 
original  bulk. 

Percentage.  Composition  (average)  of  Condensed  Milks  ' 


- 

AVater 

Proteid 

Fat 

Lactose 

Cane- 
sugar 

Salts 

Proportion  of 

nitrogenous  to 

non-nitrogenous 

food-stuffs  as 

Condensed  milk  with  added 

cane-sugar 
Do.  without  added  sugar 
Scherff's  condensed  milk 

25-61 

59-00 

72-87 

11-79 

11-92 

8-20 

10-35 

12-42 

6-62 

13-84 
15-48 
10-63 

36-22 

2-19 
2-18 
1-68 

1  :5-2 
1  :2-3 
1  :2-l 

Some  preparations  of  condensed  milk  contain  more  sugar  than  the  aver- 
age given  above. 

Sweetened  condensed  milk  is  much  used  as  an  infant  food,  especially 
among  the  lower  classes.  For  very  young  children  it  is  diluted  to  the 
strength  of  one  teaspoonful  to  four  or  five  tablespoonfuls  of  water.  Accord- 
ing to  J.  Forster  a  child  of  four  to  five  months  of  age  ought  to  have  daily 
214  grammes  of  condensed  milk,  i.e.  7|  ounces.  This  would  (on  an  average) 
contain  as  the  daily  food  21-3  grammes  of  proteid,  18"4  grammes  of  fat,  and 
98"2  grammes  of  carbohydrate,  with  about  5  grammes  of  salts.  The  pro- 
portion of  nitrogenous  to  non-nitrogenous  foodstuffs  is  in  this  diet  1  to  5 "4, 
which  is  a  great  deal  too  high.  The  amount  of  sugar  is  excessive  and  the 
fat  deficient. 

Average  Composition'^  (percentage) 


- 

Water 

Alcohol 

Lactic 
acid 

Carbonic 
acid 

Lactose 

Proteid 

Pat 

Salts 

Glycerine 

Koumiss       from 

mare's  milk  .  90-44 
Koumiss       from 

cow's  mdlk  .  89-20 
K^phir        .        .    91-21 

1-91 

1-14 
0-75 

0-91 

0-55 
1-02 

0-857 
0-86 

.1-77 

4-09 
2-4 

2-24 

2-66 
3-49 

1-46 

1-83 
1-44 

0-22 

0-43 
0-68 

0-16 

Other  preparations  of  milk  are  koumiss  and  kephir.  These  were  both 
originally  prepared  from  mare's  milk,  by  a  peculiar  process  of  bacterial  fer- 
mentation, in  the  Caucasus  ;  koumiss  is,  however,  now  made  from  cow's 


>  Konig,  op.  cit. 
VOL.   I. 


2  From  Konig,  opi.  cit. 
F  P 


434  EYGIENE 

luilk  as  well.  They  both  contain  free  carbonic  acid  and  lactic  acid,  with 
some  alcohol.  In  kepliir  the  casein  is  partially  changed  into  albumose  and 
peptone.  Both  preparations  are  used  as  food  in  phthisis  and  in  cases  of 
vomiting. 


Examination  of  Milk.    Adultebations 

Milk  is  so  largely  used  as  an  article  of  diet,  and  so  important  a  food  not 
only  to  the  young  but  to  adults,  that  a  regular  and  good  milk-supply  to  large 
towns  is  largely  mixed  up  with  the  well-being  of  the  inhabitants. 

Although  the  milk  from  different  cows  varies  in  composition,  yet  the  ad- 
mixture of  the  milk  given  by  a  herd  averages  the  composition  mthin  certain 
limits.  In  investigating  the  milk-supply  from  any  particular  locality  it  is 
important  to  determine  the  number  of  cows  in  a  herd,  the  age  and  race,  the 
kind  of  fodder,  the  health,  and  the  time  of  milking. 

A  single  cow  will  give  on  the  average  9  to  14  litres  of  milk  in  the  twenty- 
four  hours  ;  but  the  quantity  may  be  less  (in  poorly-fed  cows)  or  more  (soon 
after  parturition).  If  the  cow  gives  less  than  eight  litres  a  day  it  is  best  not 
to  use  the  milk  for  consumption.  Milk  also  ought  not  to  be  consumed  until  the 
expiration  of  a  fortnight  after  calving.  The  necessary  regulations  regarding 
the  animals  on  a  dairy  farm  come  under  several  headings.  The  fodder  is 
important.  All  those  substances  that  impart  a  bad  taste  to  the  milk  ought 
to  be  withheld  :  such  as  brewers'  wort,  turnips,  and  decomposed  food. 
Carrots  up  to  a  certain  quantity  are  allowable  ;  but  the  chief  food  ought  to 
be  rape-seed  cake,  bran,  corn,  hay,  and  grass.  A  regular  inspection  of  the 
animals  is  necessary,  to  see  the  quantity  of  milk  given  by  each  cow,  and  to 
investigate  the  health  of  the  animals.  The  milk  of  sick  and  weakly  animals 
must  be  excluded,  as  well  as  that  from  animals  with  diseased  udders — mas- 
titis or  tuberculosis.  Strict  cleanliness  in  the  milking  is  necessary,  and  the 
mixed  milk  of  the  herd  is,  with  advantage,  strained  to  remove  gross  impuri- 
ties, or  passed  through  two  gravel  filters  of  different  coarseness,  as  is  directed 
by  the  Copenhagen  Milk  Supply  Company. 

Microscopical  Examination. — Pure  milk  under  the  microscope  shows  a 
great  quantity  of  highly  refractive  oil  globules  floating  in  a  clear  hquid. 
These  oil  globules  are  large,  medium-sized,  and  minute  ;  they  vary  in  diameter 
between  0'017  millunetre  and  0*01  millimetre.  In  old  milk  they  are  not  so 
well  defined  as  in  fresh  milk.^  Colostrum  (the  first  milk  after  delivery)  has  a 
very  different  appearance  under  the  microscope  (fig.  87).  It  contains  very 
large  oil-globules,  some  epithelial  scales,  granular  matter,  and,  most  cha- 
racteristic of  all,  granular  corpuscles,  the  largest  of  which  are  about  0-05 
millimetre  in  diameter.  Good  milk  may  contain  some  of  these  corpuscles,  but 
they  ought  to  be  very  few  in  number.  The  fat  globules  of  milk  are  not  dis- 
solved by  ether  alone,  but  are  completely  soluble  if  milk  is  shaken  up  with 
ether  and  potash. 

Diseased  milk  sometimes  shows  abnormal  constituents.  Pus  corpuscles 
may  be  seen  in  abundance  ;  also  red  corpuscles.  Bacteria  may  be  seen  with- 
out the  aid  of  staining ;  but  if  the  appearances  are  doubtful,  they  may  be 
stained  for  fifteen  minutes  with  a  2  per  cent,  watery  solution  of  methylene  blue 
after  drying  a  drop  of  milk  carefully  on  a  cover-slip,  wasliing  off  the  excess 
of  colouring  matter  under  the  tap,  and  examining  under  the  microscope  after 
mounting  on  a  slide  with  a  drop  of  water.  If  necessary  the  fat  may  be 
removed  from  the  dried  specimen  before  staining  by  washing  it  with  ether. 

*  Hilger,  op.  cit. 


FOOD  435 

To  decide  the  kind  of  bacteria  present,  cultivations  must  be  made.  Staining 
in  this  way  is  also  the  best  method  for  showing  pus  corpuscles.  For 
tubercle  bacilli  the  cover-glass  is  prepared  in  the  same  way,  and  stained  for 
five  minutes  in  warmed  carbohc-fuchsin  solution  (Ziehl's  solution]  ;  de- 
colourised in  25  per  cent,  sulphuric  acid,  washed  in  water,  stained  with 
methylene  blue,  washed  again,  dried,  and  mounted  in  Canada  balsam. 
Several  preparations  must  be  made. 

Variations  in  the  Composition  of  Milk 

Specific  gravity 1028-1034 

Water 85-88  per  cent. 

Casein  &c.  (albumin,  0"05-4-5)       .        .        .  2*5-5        „ 

Fat 2-7-6 

Lactose 3-5-6         „ 

Salts 0-5-0-75    „ 

Total  solids 9-2-17-75  „ 

On  the  average,  however,  the  total  solids  should  not  be  below  12  per  cent. 

Beaction  of  Milk. — Milk  is  normally  alkahne  (shghtly).  London  milk  is 
usually,  however,  slightly  acid  ;  this  is  due  either  to  change  in  the  milk  in 
the  milk  ducts  or  after  it  has  been  drawn.  Strong  acidity  means  lactic  or 
butyric  acid,  the  presence  of  which  may  be  demonstrated  by  shaking  the 
milk  with  ether,  which  dissolves  them  ;  the  casein  is  usually  coagulated  in 
such  milks.  Strong  alkalinity  may  mean  added  sodium  bicarbonate  or 
diseased  milk. 

Adulterations  of  Milk 

1.  Water  may  be  added  to  the  milk. 

2.  A  common  adulteration  is  removing  part  of  the  cream  and  adding 
water  to  brmg  the  specific  gravity  up  to  the  normal ;  or  removing  the  cream 
from  the  evening  milk  and  adding  the  morning  milk. 

3.  Sodium  bicarbonate,  borax,  boric  acid,  and  salicyhc  acid  are  added 
to  preserve. 

4.  Starch,  flour,  gum,  dextrine  may  be  added. 

1.  An  excess  of  water  may  sometimes  be  detected  by  taking  the  specific 
gravity.  This  is  done  by  means  of  a  lactometer  (an  accurate  hydrometer), 
and  must  be  done  at  15°  0. ;  or,  if  at  other  temperatures,  the  result  must  be 
corrected  for  15°  C. 

In  good  milk  the  specific  gravity  is  from  .  .  .  1028-1034 
In  creamed  milk  the  specific  gravity  is  from  .  .  1033-1037 
In  half-creamed  milk  the  specific  gravity  is  from        .     1031-1034 

This  method,  however,  has  to  be  supplemented  by  the  following  methods 
and  by  estimating  the  total  sohds. 

To  estimate  the  total  solids,  take  10  grammes  (weighed)  of  milk,  add  two 
drops  of  acetic  acid  and  2  c.c.  of  alcohol,  and  evaporate  to  dryness  in  a  water- 
bath,  afterwards  keeping  for  some  time  at  105°  C.  The  total  sohds  ought 
not  to  be  below  12  per  cent. 

2.  The  detection  of  deficiency  in  cream  is  the  most  important  point  in 
the  examination  of  milk. 

The  cream  may  be  estimated  in  a  cylindrical  vessel,  graduated  in  100 
parts  (creamometer).  Fresh  milk  is  poured  into  the  vessel  up  to  the  gradua- 
tion, and  kept  for  twenty-four  hours  at  a  temperature  of  10°-15°  C.  The 
cream  floats  on  the  top,  and  ought  to  measure  10-15  volumes  per  cent.  In 
half-creamed  milk  the  amount  is  5-6  volumes.    The  cream  may  be  removed, 

ff2 


436 


HYGIENE 


and  the  specific  gravity  of  the  underlying  watery  liquid  (containing  salts, 
lactose,  and  casein)  may  be  taken.  The  specific  gravity  ought  to  be 
2-5°-3'5°  higher  than  that  of  the  whole  milk.  If  less  than  2-5°  higher  it 
shows  admixture  of  water  (Hilger). 

Fat  in  good  milk  ought  not  to  be  less  than  3  per  cent.,  and  in  creamed 
milk  not  less  than  1  per  cent. 

The  amount  of  fat  may  be  determined  in  the  following  manner : 
Ten  grammes  (weighed)  of  milk  are  mixed  with  20  grammes  of  burnt 
gypsum,  and  evaporated  to  di-yness  in  a  water-bath.     The  fat  in  the  residue 
is  extracted  by  ether,  and  the  ethereal  solution  after  removal  is  evaporated, 
and  the  residue  dried  at  105°  C.  and  weighed. 

3.  Sugar  is  estimated  by  titrating  with  Fehling's  solution  ;  10  c.c.  of 
this  solution  is  decomposed  by  O'OGTt)  gramme  lactose. 

4.  In  the  detection  of  starch,  &c.,  50  c.c.  of  milk  is  diluted  with  200  c.c. 
of  water,  heated,  and  alcohol  is  added  to  coagulate  the  proteid.  The  mixture 
is  then  filtered,  and  the  filtrate  evaporated  to  half  its  bulk  (or  less).  In  this 
filtrate  great  alkalinity  usually  means  sodium  bicarbonate. 

Starch  is  shown  by  the  blue  colour  with  iodine  ;  and  if  starch  is  absent, 
dextrine  is  indicated  by  the  red  colour  with  iodine.  Gum  is  precipitated  from 
the  filtrate  by  alcohol.  Salicylic  acid  is  shown  by  the  violet  colour  on  the 
addition  of  perchloride  of  iron. 

The  serum-albumin  may  be  estimated  in  the  whey  after  clotting  a  mea- 
sured portion  of  the  milk  by  rennet,  A  measured  quantity  of  the  filtered 
whey  is  precipitated  by  excess  of  alcohol,  the  precipitate  collected,  washed 
with  ether  and  alcohol,  dried  and  weighed. 


Milk  Products  : — Skimmed  Milks  ;  Cream  ;  Butter 

The  cream  may  be  removed  from  the  milk  by  allowing  the  milk  to  stand, 
or  by  the  centrifugal  machine.  The  liquid  remaining  is  skimmed  milk,  and 
is  a  useful  article  of  food.  The  composition  of  these  products  is  shown  in 
the  following  table  : — 


Composition  in 

LOO  parts 

- 

Water 

Proteids 

Fat 

Lactose 

Salts 

Lactic  acid 

Cream        .... 

Centrifugalised  milk ' 
SVimmed  milk  . 
Buttermilk 
Butter  (English) 

68-82 

90-60 

90-12 

90-6 

13-33 

3-76 

3-06 

4-03 

3-8 

1-06 

22-66 
0-31 
1-09 
1-2 

84-40 

0-59-5-52 
5-29 
4-04 
3-4 

0-53 
0-74 
0-72 

1-21 

0-32 

Cream  varies  in  composition. 

Specific  gravity 1004-1025 

Fat from  18-70  per  cent. 

Water „       20-76 

It  is  adulterated  with  albumin,  starch,  and  sometimes  other  insoluble 
substances.     The  methods  of  examination  are  the  same  as  those  for  milk. 

Cream  may  be  utiHsed  for  feeding  the  child  when  the  casein  of  milk 
disagrees.    According  to  Kehrer  and  Biedert  (quoted  by  Spiegelberg  3),  125  c.c. 

'  The  composition  of  skimmed  milk  is  closely  similar  to  that  of  centrifugalised  milk. 
*  Konig,  quoted  by  Forster.     Buttermilk  varies  greatly  in  composition  :  it  often  con- 
tains much  less  fat  (0-5  per  cent.)  and  more  lactic  acid  than  in  the  analyses  given. 
s  Op.  at.  p.  331. 


FOOD  437 

of  cream  must  be  mixed  with  375  c.c.  of  boiled  water  in  which  15 
grammes  of  milk-sugar  have  been  dissolved.  The  proportion  in  English 
measure  is,  cream  one  ounce,  water  three  ounces,  milk-sugar  one  drachm. 
The  mixture  contains  1  per  cent,  of  casein,  about  6\  per  cent,  of  fat,  and  about 
4  per  cent,  of  sugar ;  if  necessary,  the  amount  of  fat  can  be  reduced.  An 
eighth  of  a  litre  (4^  ounces)  is  to  be  given  every  two  hours. 

Buttermilk  and  skim  milk  are  useful  articles  of  diet ;  they  may  be  thick- 
ened with  carbohydrate  (starchy)  food,  and  are  serviceable  in  the  dieting  of 
children  and  of  dyspeptics. 

An  alkaloid,  tyrotoxicon,  may  be  present  in  decomposed  cream  and  cause 
serious  symptoms  of  poisoning  (Vaughan). 

Butter 

Butter,  the  fat  of  milk,  is  one  of  the  most  important  articles  of  diet,  being 
;an  easily  assimilated  form  of  neutral  fat.  The  well-to-do  take  a  large  part 
of  their  fat  in  this  way.  It  consists  chiefly  of  neutral  fats,  mixed  with  water 
and  a  small  proportion  of  casein  and  salts  (see  above).  These  fats  are  the 
glycerides  of  oleic,  palmitic,  and  stearic  acids,  with  smaller  quantities  of  the 
glycerides  of  myristic  and  butyric  acids,  and  of  the  higher  fatty  acids,  such  as 
caproic,  caprylic,  &c.  When  rancid  it  contains  free  fatty  acids  with  the  decom- 
position products  of  glycerine  (acrolein,  &c.)  and  is  apt  to  cause  or  to  aggravate 
the  symptoms  of  acid  dyspepsia.  The  average  amount  taken  daily  is  about 
:28  grammes  (one  ounce),  which  contains  about  24  grammes  of  neutral  fat,  or 
about  two-fifths  of  the  daily  allowance  of  fat  for  an  average  man  in  moderate 
work. 

Variations  in  Composition. — The  water  in  fresh  butter  is  from  6  to  30 
per  cent.,  the  fat  70  to  95  per  cent.,  and  the  casein,  lactose,  and  salts  (which 
may  be  reckoned  together)  from  0'9  to  6  per  cent. 

The  greatest  amount  of  water  ought  to  be  12  per  cent. ;  quantities  above 
ithis  represent  water  added  to  give  weight.  The  casein,  lactose,  and  salts 
ought  not  to  be  more  than  2  per  cent.,  and  the  fat  must  be  at  least  86  per 
■cent. 

In  fresh  butter  the  added  chloride  of  sodium  should  not  be  more  than 
0*5  to  2  per  cent.  Strongly  salted  butter  contains  about  8  per  cent,  of  added 
salt,  and  16  per  cent,  of  water.  Salt  is  almost  absent  from  French  butter, 
,and  boric  acid  is  added  as  a  preservative. 

Adulterations  of  Butter. — Butter  is  generally  coloured  by  such  substances 
as  saffron,  curcuma,  annatto,  &c.  No  deleterious  effect  can,  however,  be 
ascribed  to  these  additions. 

Insoluble  substances  may  be  added  to  give  weight,  such  as  potato- starch, 
chalk,  gypsum,  and  sometimes  alum  and  free  alkalies. 

Foreign  fats  are  the  most  important  addition  :  tallow,  lard,  artificial 
butter,  palm  oil,  cocoa-nut  oil,  and  rapeseed  oil. 

Method  of  Examination  of  Butter. — The  smell  and  taste  of  butter  are 
characteristic.  On  saponifying  with  alkalies  it  gives  the  characteristic  smeU 
of  the  compound  ether  of  butyric  acid,  which  is  not  perceived  if  the  product 
saponified  is  artificial  butter.^  , 

The  amount  of  water  present  in  butter  may  be  estimated  by  drying  the 
butter  at  110°  C,  and  weighing  before  and  after.  A  very  small  quantity  of 
-water  is  suspicious  of  foreign  fat  (Angell,  quoted  by  Parkes). 

The  amount  of  fat  is  estimated  by  dissolving  it  in  ether,  evaporating  the 
ether  solution,  drying  and  weighing.     After  dissolving  the  fat  in  ether,  the 

'  A.  Hilger,  Ziemssen's  Handbuch  der  Hygiene,  Th.  1,  Abth.  1,  1882,  p.  237. 


438  HYGIENE 

residue  consists  of  casein,  lactose,  and  salts.  The  casein  is  estimated  by  wash- 
ing the  residue,  drying,  and  weighing  ;  it  ought  not  to  be  more  than  I'OG  per 
cent. 

The  added  chloride  of  sodium  is  estimated  by  titrating  with  the  standard 
solution  of  silver  nitrate,  after  solution  of  the  fat  in  ether. 

Detection  of  gross  impurities  in  butter :  starch,  gypsum,  sulphate  of 
barium,  &c. 

Hilger  recommends  the  following  method.  To  from  five  to  ten  grammes 
of  butter  add  twice  the  volume  of  water  with  a  little  alcohol,  and  keep  the 
mixture  at  the. melting  pouit  of  the  butter  for  a  short  time.  The  fat  sepa- 
rates from  the  watery  substratum  and  may  be  removed.  The  watery  layer 
may  contain  in  solution  the  added  colouring  matter,  borax,  free  alkali,  alum, 
and  sodium  chloride,  and  traces  of  salicylic  acid.  The  insoluble  impurities 
sink  to  the  bottom,  and  may  consist  of  starch,  barium  sulphate,  chalk,  &c. 
The  microscope  detects  the  starch  grains,  as  does  a  solution  of  iodine,  and 
chemical  tests  detect  the  other  insoluble  impurities. 

Detection  of  the  Admixture  of  Foreign  i^a^s.  —Foreign  fats,  chiefly  animal, 
such  as  beef  and  mutton  fat  and  lard,  are  the  most  important  adulterations- 
of  butter. 

There  are  several  methods  for  the  detection  of  these  impurities. 

1.  SjJeciflc  gravity  (Bell's  method). 

The  fat  is  first  melted  at  100°  F.,  and  the  specific  gravity  estimated  by 
weighing  in  a  specific-gravity  bottle. 

The  specific  gravity  of  butter  ought  never  to  be  below  910 ;  as  a  rule  it  is 
between  911  and  913  ;  if  adulterated  butter,  it  is  902-904  ;  if  artificial  butter, 
it  is  859  ;  and  if  lard,  beef  fat,  and  mutton  fat,  it  is  8G0-8G2. 

2.  Determination  of  the  melting  point  of  the  fat. 

The  fat  is  first  separated  from  the  other  constituents  of  the  butter,  and 
the  melting  point  determined  by  gradually  heating  the  fat  in  a  water-bath. 
The  following  table  of  melting  points  is  given  by  Hilger  : — 

Melting  point 

Butter  (dehydrated) 30-8°-35°C. 

Butter  fat 32-5°-36'" 

Lard ,        .  41°-42° 

Beef  fat 42°-44° 

Mutton  fat 47°-51° 

Artificial  butter 28°-31° 

Palm  oil 30°-44° 

Cocoa  fat 28°-35° 

Parkes  attached  great  importance  to  the  determination  of  the  melting 
point,  and  variations  from  the  average  are  sure  indications  of  admixture  of 
foreign  fats,  especially  beef  fat  and  lard.^ 

3.  The  microscope  may  indicate  foreign  fats  by  discovering  crystals  of 
margaric  and  stearic  acids.  Pure  butter  shows  only  oil  globules.  The 
microscopic  tests  require  to  be  supplemented  by  the  other  tests  mentioned,, 
and  by  the  following  : — 

4.  Determination  of  the  fixed  {insoluble)  fatty  acids  (Hehner).^ 

This  method  is  based  on  the  fact  that  the  fixed  fatty  acids  obtainable 
from  butter  differ  in  amount  from  those  obtainable  from  other  animal  fats. 

'  See  Parkes's  Pract.  Hygiene,  Tth  ed.,  p.  307,  where  a  useful  table  is  given  of  the- 
temperatures  of  fusion  and  solidification  of  different  fats. 
■'  Chem.  News,  1877. 


FOOD  43a 

From  butter,  86'5-88  per  cent,  of  fixed  fatty  acids  is  obtainable  ;  from  other 
animal  fats,  95-28-95-8. 

To  5  grammes  of  butter  fat  50  c.c.  of  alcohol  containing  2  grammes  of 
caustic  potash  (KHO)  is  added,  by  which  the  fat  is  saponified.  The  soaps 
are  dissolved  in  150  to  200  c.c.  of  water  and  decomposed  with  hydric  chloride. 
The  separated  fatty  acids  are  filtered  and  washed  with  two  litres  of  boiling 
water,  and  dried  at  95°  to  98°C. ;  they  are  then  weighed. 

If  the  fixed  fatty  acids  are  over  90  per  cent.,  there  is  admixture  of  foreign 
fat  in  the  butter.  ^ 

Artificial  Butter — Margarine 

Oleo-margarine  was  first  manufactured  by  a  process  discovered  by  M6ge- 
Mouries.^  Several  products  have  since  that  time  been  sold  under  the  name 
of  hutterine  ;  all  such  products  are  now  by  law  (1887)  directed  to  be  called 
margarine.  Oleo-margarine  is  chiefly  made  from  beef  fat,  from  which  most 
of  the  stearin  is  removed  ;  the  product  is  mixed  with  milk,  and  colouring  and 
flavouring  compounds.  Other  '  margarines  '  are  made  from  beef  fat,  olive 
oil,  and  milk,  and  others  from  tallow,  lard,  rapeseed  oil,  and  palm  oil.^ 

They  have  not  the  characteristic  smell  of  butter  either  when  fresh  or 
when  saponified.  The  fixed  fatty  acids  obtainable  from  them  are  from  92  to 
95  per  cent.  The  average  melting  point  is  28°  C.  to  31°  C,  and  the  average 
composition  is  8  to  15  per  cent,  of  water,  80  to  92*5  per  cent,  of  fat,  and  5  to 
6  per  cent,  of  casein,  colouring  matter,  and  salts. 

As  an  an  article  of  food,  margarine  supplies  to  the  poorer  clases  a  cheaper 
fat  than  butter,  and,  although  not  so  assimilable,  it  is  yet  of  great  nutritive 
value. 

Cheese 

Cheese  is  an  important  product  of  milk.  It  is  made  from  milk  simply,  or 
milk  to  which  cream  is  added,  or  from  milk  with  the  cream  for  the  most  part 
removed.  Different  kinds  of  cheese  thus  vary  in  composition,  chiefly,  how- 
ever, in  the  amount  of  fat  they  contain.  They  all  contain  casein,  fat,  lactose, 
salts  (with  in  some  cases  added  sodium  chloride),  and  water ;  but  the  organic 
foodstuffs  have  during  the  ripening  of  cheese  undergone  decomposition, 
chiefly  the  fat  and  casein,  and  to  some  extent  the  lactose  ;  so  that  cheese 
contains  free  fatty  acids,  butyric,  lactic,  and  some  of  the  higher  fatty  acids. 
Considered  as  a  food,  the  smaller  amount  of  free  acids  the  cheese  contains,, 
the  better  is  it.  It  also  contains  leucin,  tyrosin,  and  ammonium  salts. 
They  react  either  alkaline  or  acid  to  test  paper.  As  an  article  of  diet  cheese 
is  very  useful,  since  it  contains  a  large  quantity  of  proteid  or  fat  in  a  con- 
centrated form.  But  this  concentration  is  from  the  point  of  view  of  digesti- 
bihty  a  great  drawback,  since  the  harder  the  cheese  is,  the  more  difficult  of 
digestion  is  it,  and  remaining  a  long  time  in  the  stomach  it  sets  up  and 
aggravates  the  symptoms  of  fermentative  or  acid  dyspepsia.  Some  people, 
too,  even  with  healthy  digestions,  cannot  eat  cheese  ;  and  this,  taken  with  the 
general  indigestibility  of  the  substance,  makes  the  nutritive  value  of  cheese 
much  smaller  than  would  appear  from  its  composition,  and  from  experiments 
with  artificial  digestion.* 

Composition  of  Cheese. — This  varies  according  to  the  milk  from  which 

'  For  Eeichart's  method,  whicli  is  an  estimation  (in  terms  of  alkalinity)  of  the  volatile 
fatty  acids  obtainable  from  butter,  see  Zeits.  Anal.  Chem.  1879,  p.  68,  or  Hilger,  op.  cit. 

2  See  Boudet,  Bapp.  fait  au  Conseil  d'HygUne,  etc.,  autoris.  la  Vente  de  la  Margarine 
Mourids.    Paris,  1872. 

^  Cf.  Hilger,  op.  cit. 

*  For  an  account  of  these  see  Konig,  op.  cit.  p.  382. 


440 


HYGIENE 


the  cheese  is  made,  and  according  to  the  length  of  time  during  which  the 
cheese  'ripens.' 

Cream  cheese  is  made  from  cream  or  cream  and  milk.  In  it,  therefore, 
the  fat  is  in  greater  proportion  than  the  casein. 

'  Fatty  cheese  '  is  made  from  milk  simply. 

'  Half-fatty  cheese  '  is  made  from  equal  parts  of  skimmed  milk  (evening 
milk  allowed  to  stand  twelve  hours)  and  of  morning  milli.  In  it  the  fat  is 
about  equal  to  the  casein. 

'  Lean  cheese  '  ^  is  made  from  skimmed  milk  or  partially  skimmed  milk. 
The  fat  in  it  is  much  less  than  the  casein. 


Percentage  Compo. 

^itioii  of  Cheeses 

- 

Water 

Casein 

Pat 

Lactose, 
&c. 

Salts 

Sodium 
chloride.adJed 

1.  Cream  cheese      .... 

2.  Fatty  cheese  (such    as   Stilton, ^ 
Cheddar,  Gloucester,  Gorgonzola, 
Roquefort)    ..... 

3.  Half -fatty       cheese      (Gruy^re, 
Dutch) 

4.  Lean  cheese  (such  as  Parmesan) 

30-66 

380 

39-79 
31-80 

2-84 

25-35 

29-67 
41-19 

62-99 

30-25 

23-92 
19-52 

2-03 

1-43 
1-79 

ri8 

1-15 

4-97 

4-73 
6-31 

2-37 
1-97 

Compared  to  medium  fat  beef,  a  fatty  cheese  contains  1*2  time  more 
proteid  and  5*6  times  more  fat. 

Bad  Effects  of  Cheese. — Besides  the  effect  on  digestion  above  mentioned, 
cheese,  when  it  has  become  sour,  may  cause  diarrhoea.  The  ptomaine, 
tyrotoxicon,  may  also  be  developed  and  cause  symptoms  of  poisoning. 

Adulterations. — Starch  is  the  commonest  addition  to  give  weight.  It  is 
detected  by  the  blue  colour  given  with  iodine.  The  fat  may  also  be 
removed  with  ether,  so  that  the  residue  is  easily  examined  microscopically 
for  starch  grains  and  coarse  additions. 

Small  quantities  of  copper,  zinc,  and  lead  may  be  found  in  the  ash. 
Arsenious  acid  may  be  found  in  the  rind. 

Cheese  often  becomes  green  and  red,  owing  to  the  development  of  fungi ; 
and  an  acarus  (cheese-mite)  commonly  is  found  in  old  cheese.  When 
mouldy,  cheese  contains  in  large  quantity  the  products  of  decomposition  by 
bacteria. 

EGGS 

Hens'  eggs  are  the  usual  form  in  which  eggs  are  eaten  as  food,  but  ducks' 
eggs  are  also  used,  and  on  the  sea-coast  the  eggs  of  sea-fowl. 

Cmjqyositioii. — Hens'  eggs  vary  greatly  in  size  and  in  weight.  Thus 
small  eggs  weigh  between  45  and  50  grammes,  the  medium-sized  between 
55  and  60  gi'ammes,  and  the  large  ones  70  grammes  or  over  (Forster).  The 
average  weight  is  about  58  grammes  (two  ounces). 

The  shell  forms  10  per  cent,  of  the  weight ;  it  is  relatively  greater  in  the 
smaller  eggs  than  in  the  larger.  The  egg  itself  consists  of  two  parts — the 
white  and  the  yolk  in  the  proportion  of  67  to  33.  The  white  contains  chiefly 
albumin  (egg-albumin),  with  a  trace  of  fat  and  a  small  proportion  of  salts  ; 
the  yolk  contains  a  globulin  (vitelHn)  and  a  large  quantity  of  fat  and  a  larger 
proportion  of  salts  than  the  white. 

'  The  German  terms  '  Fettkase,'  '  Halbfetterkase,"  Magerkase,'  have  been  literally 
translated  to  express  these  different  kinds  of  cheese. 

^  Stilton  is  sometimes  considered  as  a  cream  cheese,  but  in  composition  it  belongs  to 
Class  2. 


FOOD 


411 


Composition  c 

)/  the  Hell's 

Egg  (Konig) 

- 

Water 

Proteid 

Pat 

Free  extractions 

Salts 

Whole  egg  (less  shell)    . 
White  of  egg  . 
Yolk  of  egg     . 

73-67 

85-5 

51-03 

12-55 

12-87 
16-12 

12-11 

0-25 

31-3'J 

0-55 

0-77 
0-48 

1-12 
0-61 
1-01 

The  yolk  of  ducks'  eggs  contains  more  fat  than  that  of  hens'  eggs.  The 
fatty  bodies  of  the  yolk  consist  of  the  neutral  fats — palmitin  and  olein, 
cholesterin  and  lecithin.  A  small  quantity  of  grape-sugar  is  also  found,  and 
the  most  important  mineral  constituent  present  in  the  yolk  is  iron  united 
with  an  organic  body.  Potassium  and  phosphates  are  in  excess  in  the  salts 
over  sodium  and  chlorides.  In  the  white,  the  sodium  and  chlorides  are  in 
excess. 

Ptomaines  have  been  found  in  eggs  (Gautier)  and  albumoses,  but  only 
in  very  small  quantities  ;  the  presence  of  both  these  classes  of  bodies  is  to  be 
ascribed  to  incipient  decomposition. 

Digestibility  of  Eggs 

According  toEubner,  with  an  egg  diet  most  of  the  proteids  are  absorbed, 
only  about  3  per  cent,  of  nitrogen  being  found  in  the  faces  (equal  to  about 
20  per  cent,  proteid),  while  the  fat  is  not  so  well  absorbed,  about  5  per  cent, 
appearing  in  the  fasces.  Eggs  disagree  with  some  people,  and  when  in- 
cipient decomposition  is  established  ought  not  to  be  eaten. 

Preservation  of  Eggs 
Eggs  are  preserved  by  excluding  air  from  entering  through  the  shell. 
This  may  be  done  by  covering  the  shell  with  oil  or  gum,  or  with  insoluble 
lime  compounds.     Good  eggs  sink  in  a  10  per  cent,  solution  of  common 
salt :  bad  ones  float. 


FLESH 

The  muscular  tissue  of  various  animals — chiefly  herbivorous — and  of  fish 
and  of  birds,  forms  one  of  the  chief  foods  of  adult  man.  Not  only,  however,  is 
the  muscular  tissue  utilised,  but  also  some  of  the  internal  organs,  and  some 
invertebrate  animals  are  also  eaten.  These  will  all  be  considered  under  the 
heading  of  Flesh. 

Meat 

The  flesh  of  many  animals  is  eaten  by  man  in  different  parts  of  the 
world :  but  that  chiefly  used  is  obtained  from  the  ox  (beef),  the  calf  (veal), 
the  sheep  (mutton),  the  pig  (pork),  and  the  goat.  The  flesh  of  wild  animals 
(deer,  &c.)  is  also  eaten,  but  it  is  in  civilised  countries  a  luxury,  and  does  not 
enter  into  the  dietary  of  the  majority. 

Composition 

Flesh  in  the  form  of  meat  is  a  food  containing  many  substances.  It  is 
chiefly  utihsed  as  a  proteid,  a  fatty,  or  a  saline  food,  the  carbohydrate  con- 
stituents being  in  very  small  quantity.  The  chief  proteid  is  myosin,  which 
exists  in  the  muscle-fibre  itself,  and  constitutes  the  greater  part  of  the  amoimt 
■of  nitrogenous  element  mentioned  in  the  table.  It  is  a  globuhn,  soluble  only 
in  saline  solutions,  and  in  dilute  acids  and  alkalies,  and  is  coagulated  by  a 
lieat  below  100°  C.  These  properties  show  why  it  is  not  present  in  solution 
in  ordinary  beef-tea.  Myosin  itself  is  the  result  of  coagulation  of  the  hving 
muscle  which  occurs  on  its  death — that  is,  on  the  onset  of  rigor  mortis.     The 


442 


HYGIENE 


meat  is  in  this  state  hard.  "When  the  rigor  mortis  passes  off  the  meat  be- 
comes tender  and  is  fit  for  cooking. 

Other  proteids  present  in  meat  are  a  small  quantity  of  alkali- albumin,' 
serum-albumin,  and  globulin  derived  from  the  blood ;  gelatin  formed  in  the 
process  of  cooking  from  the  connective  tissue  surrounding  the  fibres,  the 
vessels,  and  nerves,  and  a  small  quantity  of  elastin.  The  next  most  important 
dietetic  constituent  of  meat  is  the  fat.  This  exists  attached  to  the  muscles 
(part  of  the  subcutaneous  fat),  but  in  well-fed  and  in  fattened  animals  it  is  found 
in  the  connective  tissue  between  the  muscle  fibres ;  meat  may  thus  be  spoken 
of  as  fat,  medium  fat,  and  lean,  and  these  three  kinds  have  necessarily  a 
different  dietetic  value  in  considering  a  given  dietary.  The  amount  of  fat  in 
the  meat  varies  in  diflerent  kinds  of  beef,  in  mutton,  and  especially  in  pork, 
which  is  thus  rendered  indigestible.  The  fiesh  of  young  animals  (calf  and 
lamb)  is  lean  meat. 

The  fat  itself  solidifies  after  death  and  is  composed  of  stearin,  palmitin, 
and  olein  in  different  proportions,  the  more  solid  fats  containing  an  excess  of 
stearin  (see  p.  395). 

The  saline  constituents  of  meat  consist  mainly  of  potassium  and  phos- 
phoric acid;  magnesium  is  in  greater  abundance  than  calcium.  Sodium  and 
chlorine  are  in  less  quantity.  This  follows  the  general  rule  that  the  hquids 
of  the  body  contain  sodium  and  chlorine  in  excess  of  potassium  and  phosphate, 
while  in  the  solid  parts  of  the  tissues  the  reverse  holds  good.  In  1,000  parts 
of  the  ash,  there  are  4-654  parts  of  KgO,  0-770  of  Na,0,  0-086  of  CaO,  0-412 
of  MgO,  0-057  of  FeoOg,  4-644  of  Podj,  0-672  of  CI,  and  a  trace  of  SO2. 

Glycogen  is  the  chief  carbohydrate  in  meat ;  it  forms  usually  only  0-5  per 
cent.  After  death  it  is  mostly  changed  into  grape-sugar.  Inosit  (muscle 
sugar)  is  isomeric  with  grape-sugar ;  it  occurs  in  very  small  quantity. 
The  so-called  extractives  of  meat  are  important,  since  they  constitute 
the  stimulating  principles  of  beef-tea  and  other  broths.  These  are  mostly 
nitrogenous  crystalline  bodies  derived  from  the  proteid  metabolism  of  the 
muscle  ;  creatine  and  creatinine  are  the  chief,  but  taurin,  sarkine,  xanthine^ 
carnine,  urea,  and  uric  acid  also  occur  to  a  less  extent. 

Sarcolactic  acid  is  a  product  of  the  activity  of  muscles  ;  it  is  formed  to 
a  great  extent  during  rigor  mortis. 


- 

Water 

Nitrogenous 
substances 

Fat 

N.-free 
extractives 

Ash 

Proportion  of 
nit.  to  non- 
nit,  foodstuffs 

Beef  (very  fat) 

53-05 

16-75 

29-28 



0-92 



„     (medium  fat) 

72-03 

20-96 

5-41 

0-46 

1-14 

1  :  0-28 

,,    (lean)    .... 

76-37 

20-71 

1-74 

— 

1-18 

— 

Veal  (fat)      .... 

72-31 

18-88 

7-41 

0-07 

1-33 

— 

.,     (lean)    .... 

78-84 

19-86 

0-82 

— 

0-50 

1 :  0-04 

Mutton  (very  fat)  . 

53-31 

16-62 

28-61 

0-54 

0-93 

— 

„       (medium  fat)    . 

75-99 

17-11 

5-77 

— 

1-33 

1 :  0-33 

Pork  (fat)      .... 

47-40 

14-54 

37-34 

— 

0-72 

1  :  2-57 

(lean)  .... 

72-57 

20-25 

6-81 

— 

1-10 

1  :  0-33 

Horseflesh     .... 

74-27 

21-71 

2-55 

0-46 

1-01 

1  :  014 

Internal  organa  : 

Tongue  and  heart 

G5-66 

19-61 

13-75 

0-10 

0-88 

1:0-7 

Kidney''^     .... 

76-58 

16-64 

5-56 

0-10 

1-12 

1  :  0-34 

Liver          .... 

71-39 

19-7-2 

5-55 

1-69 

1-65 

1  :  0-36 

The  preceding  table  gives  the  percentage  composition  of  different  kinds  of 
meats  (Konig). 

'  This  alkali-albumin  is  formed  from  the  globulin   of  muscle   when   the   tissue  i» 
alkaline.  -  Average  of  ox,  sheep,  and  pig's  kidney. 


FOOD 


443 


Meat  is  chiefly  a  proteid  and  fatty  food.  It  is  not  to  be  deduced  that  the 
amount  of  nitrogenous  substances  given  in  the  above  table  is  completely 
available  for  assimilation.  In  other  words,  the  21  per  cent,  of  nitrogenous 
substances  in  beef  does  not  consist  solely  of  myosin  and  serum  albumin, 
which  are  of  great  nutritive  value,  but  also  of  gelatin  and  elastin,  the  nutri- 
tive values  of  which  are  not  equal  to  that  of  myosin  ;  and  of  the  nitrogenous 
extractives,  which  are  stimulants  and  are  not  proteid  foods.  Parkes  gives  the 
total  proteids  of  beef  and  mutton  as  17  per  cent.,  of  which  13  per  cent,  are 
useful,  i.e.  assimilable  by  the  organism.  Rubner,  however,  found  that  only 
2"5  per  cent,  of  the  nitrogen  taken  in  as  proteid  of  meat  was  passed  out  in 
the  faeces.  This  reckons  the  percentage  of  proteids  in  meat  as  20-90,  of 
which,  therefore,  18"46  per  cent,  are  available  for  the  organism — a  higher 
reckoning  than  that  given  by  Parkes.  These  experiments  were  done  with 
good  meat.  Meat  as  sold,  however,  contains  gristle  and  bone,  and  Parkes's 
figures  may  be  taken  as  accurate  for  the  proteid  value  of  meat  inclusive  of 
gristle  but  exclusive  of  bone. 

Bone  forms  about  20-25  per  cent,  of  the  meat  as  sold.  It  is  relatively 
more  in  young  animals  ;  in  veal,  for  example,  it  forms  as  much  as  30  per  cent. 
and  over  (Forster).  Fattened  and  well-fed  animals  also  possess  relatively  less 
bone  than  the  badly  nourished.  A  well-nourished  lamb  has  5|-  per  cent,  of 
bone,  a  similar  animal  poorly  fed  over  8  per  cent,  of  the  weight  during  life 
(Weiske).  This  proportion  of  bone  is  thus  important,  as  the  meat  (inclusive 
of  bone)  obtainable  from  differently  nourished  animals  varies. 


In  thin  oxen    . 
In  medium-fed 
In  well-fed 
In  fattened  pigs 


53-60  per  cent,  of  the  life-weight  is  meat  with  bone 

55-65 

60-70 

80-85  1      „ 


A  full-grown  sheep  weighs  60-90  lb.  or  more,  and  yields  60  per  cent,  of 
available  food ;  a  full-grown  pig  weighs  100-180  lb.  or  more,  and  yields 
75-80  per  cent,  of  available  food. 

The  amount  of  fat  in  meat  varies  with  the  feeding  of  the  animals.  In  a 
fat  ox  it  forms  about  one-third  of  the  flesh,  in  a  fattened  pig  about  one-half 
(Lawes  and  Gilbert).  In  thin  and  badly  nourished  animals,  on  the  other 
hand,  the  amount  of  fat  may  be  reduced  to  1*3  per  cent  of  the  meat,  or  even 
lower  (Siegert). 

The  fat  of  animals  when  separated  varies  slightly  in  composition  in  the 
different  animals. 

Composition  of  Animal  Fats  (percentage) 


- 

Water 

Membrane 

Fat 

Proteid 

Salts 

Mutton  and  beef  suet 
Pig's  fat     . 

Lard  ..... 
Beef  tallow 

10-22 
6-44 
0-70 
1-33 

1-40 
1-35 

88-38 
92-21 
99-04 
98-15 

0-26 
0-44 

Traces 
0-08 

Artificial  butter  (margarine)  is  made  from  animal  fats  (see  p.  439). 


Variations  in  the  Composition  of  Meat 
These  have  been  partly  discussed  above.     The  amount  of  bone  varies, 
but  the  greatest  difference  between  meat  from  different  animals  is  in  the 
amount  of  fat  present.     The  flesh  of  young  animals  and  of  fish  contains 
more  gelatin  (when  cooked)  and  less  proteid  than  that  of  adult  animals. 

'  Forster,  op.  cit.  p.  165. 


iU 


HYGIENE 


Digcstih'ilihj  of  Meat — CooMng 
Both  the  preparation  and  the  digestihiUty  of  meat  have  ah-eady  been  dig. 
cussed  (p.  422) ;  also  the  preparation  of  soups,  broths,  &c. 

Fish 

Many  varieties  of  fish  are  eaten  as  food ;  both  fresh  and  in  the  dried  or 
*  cured '  state.  As  food,  however,  fish  may  be  considered  as  divided  into  two 
classes,  the  fatty  and  the  non-fatty.  Of  the  fatty,  the  salmon,  herring, 
and  mackerel  may  be  quoted  as  examples ;  and  of  the  non-fatty,  the  cod. 

Percentage  Composition  of  the  Flesh  of  Fish 


- 

Water    Protcid 

Fat 

Salts 

Snilium 
chloride 

Proportion  of 
nit.  to  non- 
nit.  foodstufEs 

Fat  Fish : 

Salmon  (Salmo  salar) 
Herring  {Clupea  harencjns) 
Mackerel  (Scomber  scombrtts) 

Lean  Fish : 

Cod  (Gadiis  morrhua,  var.  0.  cala- 
rias)     ...... 

Cured  Fish : 
Dried  cod  (unsalted) 

„          (salted)   .... 

64-29 
74-64 
71-20 

82-20 

16-16 
13-20 

21-60 
14-65 
19-36 

16-23 

81-54 
73-72 

12-72 
9-03 

8-OB 

0-33 

0-74 
3-37 

1-39 

1-78 
1-36 

1-36 

1-56 
9-92 

4-74 

1  :  0-59 
1  :  0-61 
1  :  0-41 

1  :  0-02 

Fish  are  preserved  by  smoking  and  salting. 

Diseases  Caused  by  Meat 

Meat  forming  such  a  large  proportion  of  the  diet  of  man,  it  is  evident  that 
a  proper  inspection  of  the  meat  sold  with  the  view  of  the  rejection  of  not  only 
unwholesome  meat,  but  also  of  doubtful  kinds,  is  extremely  important  to 
the  health  of  the  community.     (See  article  on  Meat  Inspection.) 

1.  Meat  may  undergo  changes  (putrefaction)  after  being  prepared  for  the 
market.  It  seems  doubtful  whether  meat,  healthy  when  prepared,  can  com- 
municate acute  infective  diseases,  after  being  exposed  to  contagion;  but  meat, 
especially  pork  and  ham,  has  been  shown  to  be  affected  by  micro-organisms, 
which  produce  a  specific  diarrhoeal  disease  in  man  (p.  445). 

2.  It  may  also  be  affected  by  drugs  which  have  been  administered  to  the 
animal,  or  by  the  peculiarity  of  its  fodder. 

3.  It  may  be  affected  by  disease  of  the  cow  ;  and  the  proper  investigation 
of  these  kinds  of  diseased  meat  is  of  the  highest  importance. 

1.  Putrefactive  Changes  of  Meat. — Healthybeef  has  a  marbled  appearance, 
is  of  reddish  colour,  firm  consistence,  and  gives  a  reddish  juice  on  allowing  it 
to  stand  some  time.  The  fat  is  firm,  whitish  yellow  in  colour,  and  does  not 
show  any  haemorrhagic  spots. 

In  putrefaction  the  meat  becomes  of  a  less  firm  consistence,  paler  in  colour, 
and  finally  emits  an  offensive  odour.  The  colour  finally  changes  to  a  greenish 
yellow,  and  parts  of  the  meat  are  easily  torn  or  become  diffluent ;  a  knife 
thrust  into  such  meat  smells  offensively  on  being  withdrawn  ;  the  marrow 
soon  decomposes  and  becomes  diffluent  and  offensive.  The  changes  awe  due 
to  the  action  of  putrefactive  bacteria,  feeding  on  the  proteid  bodies  which  are 
broken  up  with  the  production  of,  in  many  cases,  crystalline  products — the 
eo-called  cadaveric  alkaloids  or  ptomaines.' 

'  L.  Brieger,  '  JJeber  Ptomaine,''  parts  i.  and  ii.  1885  ;  part  iii.  1886. 


FOOD  445 

From  meat  (beef  and  horseflesh)  which  has  been  allowed  to  decompose 
in  water  at  the  temperature  of  the  blood  for  five  to  six  days,  Brieger  has 
separated  several  alkaloids,  neuridine,  neurine,  choline,  and,  most  important  of 
all,  an  alkaloid  apparently  identical  with  muscarine,  the  active  principle  of 
A.manita  muscaria  (Schmiedeberg  and  Koppe).  This  alkaloid  produces  the 
following  symptoms  in  animals  :  first,  a  great  increase  in  the  secretions — 
salivation,  nasal  discharge,  lachrymation,  sweating,  and  diarrha3a — the  respi- 
ration is  also  quickened,  becoming  finally  dyspnoeic,  and  with  a  large  dose 
asphyxial  clonic  spasms  may  be  noticed.  The  cardiac  beat  is  accelerated,  the 
blood-pressure  sinks,  and  the  heart  finally  stops  in  diastole.  Similar  'muscarine- 
like  '  symptoms  are  produced  by  neurine  and  choline,  although  large  doses 
require  to  be  administered.  From  decomposing  horseflesh  Brieger  separated 
a  poison  acting  like  curare — viz.  paralysing  the  ends  of  the  motor  nerves. 
From  decomposing  fish,  Brieger  has  separated  several  alkaloids — trimethyl- 
amine,  methylamine,  diethylamine,  neuridine,  cadaverine,  putrescine. 
Cadaverine  and  putrescine  do  not  appear  very  poisonous  unless  injected  into 
the  circulation,  in  which  case  they  produce  '  haemorrhages  and  ulcerations  ' 
very  similar  to  those  occurring  in  cholera. ^  They  do  not,  however,  cause 
muscular  cramps.  There  are  probably  other  poisons  in  decomposing  flesh, 
not  yet  separated.  It  is  important  to  notice  that  Brieger  found  the  poisonous 
effects  of  neurine,  choline,  and  of  muscarine  (from  decomposed  meat)  neutral- 
ised by  the  administration  of  atropine. 

The  flesh  of  some  animals  which  is  not  decomposed  may  be  poisonous  : 
the  common  mussel,  the  sea-water  mussel  {Mytilus  edulis]  and  some  Crustacea 
are  sometimes  poisonous.  No  definite  poison  has  been  separated  from  such 
animals,  with  the  exception  of  the  sea-water  mussel.  In  the  outbreak  of 
mussel-poisoning  occurring  at  Wilhelmshaven  in  Germany,  the  mussels  were 
found  to  contain  a  poisonous  alkaloid — mytilotoxine — which  produced  the 
symptoms  of  poisoning  noticed  in  the  persons  who  were  affected. 

The  symptoms  in  man  produced  by  the  consumption  of  decomposed  flesh  are 
chiefly  confined  to  the  gastro-intestinal  tract,  as  shown  in  nausea,  vomiting, 
abdominal  pain,  and  diarrhoea,  sometimes  choleraic  in  character.  With  these 
signs,  there  is  prostration  and  sometimes  a  rash  on  the  skin  of  an  urticarial 
or  erythematous  character.     Symptoms,  however,  may  be  altogther  absent. 

In  a  fatal  outbreak  of  diarrhoea  occcuring  at  Welbeck  in  1880,  Dr.  Ballard 
showed  that  the  eating  of  ham  was  the  cause,  and  (with  Dr.  Klein)  demon- 
strated that  the  disease  was  due  to  a  specific  bacillus.  This  micro-organism 
also  appeared  to  account  for  a  similar  outbreak  of  diarrhoea  at  Nottingham  in 
1881,  which  was  also  investigated  by  Dr.  Ballard.^ 

2.  The  peculiarity  of  the  fodder  may  impart  a  disagreeable  smell  to  the 
meat,  but  actual  poisonous  properties  transmitted  from  the  fodder  to  the 
flesh  is  more  often  observed  in  birds  feeding  on  certain  berries.  Beef  may 
become  poisonous  by  the  cattle  feeding  on  poisonous  plants,  delirium  and  the 
symptoms  of  narcotic  poisoning  being  observed  when  the  meat  is  eaten  by  man. 

Similarly  the  meat  of  cattle  which  have  been  dosed  with  arsenic  and  an- 
timony previous  to  slaughtering  may  cause  poisonous  symptoms — vomiting, 
diarrhoea,  &c.,  when  eaten,  owing  to  the  presence  of  the  metal  in  the  meat. 

8.  The  most  important  question  in  regard  to  the  deleteriousness  of  meat 
is  how  far  it  is  affected  by  disease  of  the  animal.     It  is  still  doubtful  to  what 

1  See  Brieger,  op.  cit.  Udranszky  and  Baumann,  Zeits.  f.  Physiol.  Chemie,  xiii.  562. 
For  further  information  on  ptomaines  see  Selmi,  Sulla  Ptomaine,  &c.  Bologna,  3  878 ; 
ihid.  1882.  Guareschi  et  Mosso,  Les  Ptomames,  Turin,  1883.  Gautier,  Sur  Us  AlcaMdes 
d6riv6s  de  la  destniction  bacterienne,  &c.  Paris,  1886. 

*  See  Report  of  Medical  Officer  of  Local  Government  Board,  1880. 


446  HYGIENE 

extent  the  diseases  of  the  animals  used  by  civihsed  man  affect  the  meat  so  as  to 
render  it  unfit  for  consumption.  Some  facts  are,  however,  definite,  and  will 
now  be  discussed. 

Disease  of  the  animal  may  affect  the  meat  in  two  ways  : — 

1.  The  meat  may  be  infected  with  the  young  of  worms. 

2.  It  may  be  altered  in  composition  by  the  general  or  local  disease  of  the 
animal,  so  as  either  to  diminish  the  nutritive  value  of  the  meat  or  to  render 
it  actually  injurious. 

Parasites  {Animal) 

a.  The  j^ig  is  infested  with  two  parasites  which  are  of  importance  to 
man  ;  both  these  have  their  habitat  in  the  flesh  (pork) :  the  one,  Cysticercus 
celluloses,  gives  rise  to  the  common  tape-worm  {Tcenia  solium)  in  man,  the 
other,  Trichina  sinralis,  gives  rise  to  a  disease  in  man,  trichiniasis,  which  is 
often  fatal. 

Cysticercus  cellulosce  maybe  detected  during  life  by  examining  the  under 
surface  of  the  tongue  ;  if  necessary,  one  of  the  vesicles  may  be  removed  for 
microscopic  examination.     The  parasite  renders  the  flesh  '  measly,'  i.e.  the 

meat  has  scattered  through  its 
substance  small,  round,  whitish 
yellow  bodies. 

A  microscopical  examina- 
tion ought,  however,  to  be 
made.  By  digesting  the  meat 
with  pepsin  and  hydrochloric 
acid  for  some  hours  at  40°  C, 
the  bladders  fill  to  the  bottom 
of  the  vessel,  and  may  then 
readily  be  examined  (Schmidt 
Fig.  90.  Fig.  91.  — Mulheim).       The     bladders 

Cysticercus  cellulosm,  with  head  retracted  (fig.  90),       yary  in  size,  and  are   COmpOSed 
and  extruded  (fig.  91).   (Leuckart.)  ,.  -xi     t       •  n  7      j 

of  a  sac.  With  liquid  contents, 
in  which  float  calcareous  and  other  particles.  At  one  part  the  sac  is  pro- 
longed into  a  head,  which  is  crowned  with  booklets.  These  booklets  are 
diagnostic  of  cysticercus,  and  are  not  readily  dissolved  by  hquor  potassas. 
The  pork  may  therefore  be  heated  for  a  few  minutes  with  the  caustic  solu- 
tion, when  the  bladders  and  numerous  booklets  will  be  set  free  if  the 
treatment  be  continued. 

Cysticerci  are  killed  by  a  temperature  of  57°-60°  C.  (Lewis),  and  as  the 
temperature  of  well-cooked  meat  is  about  65°  C.  such  meat  containing 
cysticerci  would  be  harmless  if  eaten.  But  no  dependence  can  be  placed  on 
the  meat  being  so  well  done  ;  therefore,  pork  containing  cysticerci  ought 
always  to  be  condemned  as  food.  Neither  salting  nor  the  ordinary  smoking 
kills  the  cysticerci. 

Trichiniasis  is  a  serious  result  of  eating  diseased  pork  when  imperfectly 
cooked,  and  after  being  made  into  sausages.  The  disease  is  rare  in  England, 
but  common  in  Germany. 

Trichinised  pork  shows  small  white  specks  between  the  bundles  of  muscle 
fibres  ;  these  are  the  encapsuled  worm  (figs.  92  and  93).  When  eaten,  the  eggs 
which  are  freed  in  the  alimentary  canal  develop,  and  the  embryos  pass  through 
the  walls  of  the  gut,  and  migrate  to  the  muscles  and  other  parts.  During 
this  migration  they  produce  trichiniasis,  which  first  appears  some  time  after 
the  ingestion  of  the  meat.  Diarrhoea  and  loss  of  appetite  are  often  noticed 
first.     Then  there  is  a  fever,  with  severe  muscular  pains  and  contractions. 


FOOD 


447 


weakness,  and  even  coma.     Death  may  occur  within  a  few  weeks.     The  early 
symptoms  sometimes  resemble  those  of  typhoid  fever. 

Trichinas,  when  free,  are   killed   by  a  temperature  of   63°-70°  C,  the 
albumen  becoming  coagulated.    Ordinary  smoking  does  not  destroy  them, 
nor  does   decomposition ;    hot 
smoking    is    fatal    (Leuckart). 
Trichinised   fish   is    unfit    for 
food. 

h.  The  cysticercus  of  beef 
gives  rise  to  Tcenia  meclio- 
canellata  in  man,  a  tape-worm 
without  hooklets,  and  with  four 
pigmented  suckers. 

c.  In  mutton,  Cobbold  de- 
scribed a  cysticercus  which  was 
the  young  of  Tce,nia  tenella ; 
very  little  is  known  about  it. 
The  cysticercus  has  a  double 
crown  of  hooklets. 

Flukes  are  common  para- 
sites in  the  liver  of  sheep  ;  they 
are  probably  rendered  com- 
pletely innocuous  by  cooking. 

Echinococcus  disease  aflects  sheep  and  cattle  in  Iceland :  it  gives  rise  to 
hydatid  disease  in  man,  the  original  infection  coming  from  the  adult  worm 
{Tcenia  echinococcus),  which  is  found  in  the  dog. 

The  flesh  of  domestic  animals  (beef,  mutton,  pork)  may  contain  oval 
bodies  from  3-^  to  ^  inch  in  length,  which  are  called  Psorospermia  or  Eainey's 
corpuscles.  They  are  probably  innocuous  to  man,  but  in  pigs  and  sheep  may 
produce  symptoms  of  illness. 


Pig.  92. 


Fig.  93. 


Trichina  spiralis  in  muscle  fibre  (Leuckart). 


Meat  of  Diseased  Animals 

There  is  very  little  accurate  knowledge  as  to  the  deleterious  or  non-dele- 
terious character  of  the  meat  of  animals  affected  with  general  diseases.  In 
some  cases  such  meat  has  produced  serious  symptoms  ;  in  other  cases  it  is 
harmless.  The  symptoms  are  chiefly  those  previously  described  or  caused  by 
decomposed  meat — viz.  sickness  and  diarrhcea  with  prostration,  and  in  some 
cases  fever.  The  poisons  in  the  meat  which  prodiice  these  symptoms  are  not 
known,  and  until  further  investigation  has  been  made,  it  is  impossible  to  say 
whether  they  are  alkaloidal,  or  whether  they  are  produced  from  a  trans- 
formation (non-alkaloidal)  of  the  proteids  of  the  msat. 

In  many  cases  of  disease  the  meat  is  pale  and  moist,  and  is  altered  in 
consistency.     It  may  also  be  tasteless. 

The  meat  of  cattle  suffering  from  epidemic  pleuro-pneumonia  is  considered 
by  some  harmless,  and  a  large  quantity  of  such  meat  goes  into  consumption  ; 
that  of  those  suffering  from  foot-and-mouth  disease  is  also  probably  harmless. 
Cattle  plague  is  considered  in  Belgium  to  affect  the  meat  dangerously ;  cases, 
however,  where  no  harm  has  resulted  from  the  consumption  of  such  meat 
are  recorded.  Small-pox  in  sheep  injuriously  affects  the  meat,  which  ought 
not  to  be  consumed. 

Doubt  exists  as  to  the  value  of  the  meat  of  animals  suffering  from  anthrax 
and  erysipelas  carbunculosum.  The  organism  in  anthrax  [Bacillus  anthracis) 
is  rendered  innocuous  by  exposure  to  a  temperature  of  55°  C.  (Toussaint). 


448 


HYGIENE 


T\\Q  bacilli  would  therefore  be  destroyed  in  tlie  cooking,  and  this  result  would 
explain  the  harmless  consumption  of  the  meat  in  many  cases.  Infection 
might,  however,  be  produced  by  handling  the  uncooked  meat  if  there  were  an 
abrasion  of  the  skin.  Black-quarter  (symptomatic  anthrax,  erysipelas  carbun- 
culosum)  may  cause  the  meat  to  be  poisonous  (Gamgee). 

The  question  whether  tuberculosis  can  be  transmitted  to  man  by  meat  is 
an  important  one,  which  is  not  yet  decided.  It  may  safely  be  said,  however, 
that  meat  which  contains  tubercles  in  any  stage,  and  in  which  tubercle  bacilli 
are  found,  ought  to  be  condemned  as  unfit  for  human  food  ;  and  in  London  and 
three  towns  in  the  British  Isles  lately  (1889)  this  has  been  the  magisterial 
decision.  Tubercles,  however,  are  not  commonly  found  in  meat.  The  only 
doubtful  question  is  whether  cows  affected  with  tuberculosis  (Perlsncht),  but 
in  the  meat  of  which  there  are  no  tubercle  or  tubercle  bacilli,  ought  to  be 
allowed  for  human  food — i.e.  in  cases  where  the  disease  is  limited  to  the 
internal  organs.  Such  meat  is  often  quite  normal  in  appearance.  At  present 
the  question  cannot  be  considered  as  settled. 

Peesebvation  of  Meat — Peepabations 

A  common  mode  of  preserving  meat  is  by  freezing,  and  in  a  frozen  state  it  is 
imported  in  large  quantities  from  America  and  Australasia.  Other  modes  are 
drying,  and  in  some  cases  powdering  (forming  the  so-called  '  meat  powders  '),, 
and  also  smoking,  during  which  process  the  meat  becomes  j)artly  dried. 

The  chief  defect  of  the  preparations  of  beef,  mutton,  and  veal  is  that  they 
are  unsavoury,  and  do  not  cook  well,  and  cannot  for  a  long  time  be  partaken  of 
with  advantage.  Such  preparations  are  of  chief  use  for  soldiers  and  sailors 
in  time  of  war. 

Many  extracts  of  meat  are  now  sold,  some  of  which  act  as  stimulants 
(such  as  Liebig's  Extract),  and  others  are  useful,  both  as  stimulants  and  as 
nitrogenous  foods.     The  latter  may  be  described  as  nitrogenous  beef-teas. 

In  time  of  war,  the  mixtures  of  meat  with  vegetables,  in  the  form  of 
sausages  or  concentrated  soups,  have  been  found  of  great  use ;  but  owing 
to  want  of  the  natural  flavouring  of  the  meat,  the  food  soon  causes  loss  of 
appetite  for  it.  Such  preparations  are  those  of  mutton  and  rice,  veal  and 
rice,  smoked  mutton  and  beans,  German  pea-sausage  (Erbsivurst)  made  of 
pea-flour  and  fat  pork,  with  many  others,  chiefly  Russian  preparations.^ 

The  following  table  gives  the  composition  of  some  of  these  preparations 
of  meats : — 

Freparations  of  Meat,  with  and  without  added  Vegetables  (percentage  Composition) 


Carne  pura  (American  dried  beef,  powdered) 
Hassall's  flour  of  meat  (mixed  with  8  per  cent. 

arrowroot,  8^  per  cent,  sugar,  and  3  per  cent. 

salts  and  pepper,  &c.) 

Tinned  meat  ....... 

German  pea-sausage  (Erhszuursi)  (average)  . 
Ham  (Westphalian) 


Water 

Proteids 

Pat 

N.-free 
extrac- 
tives 

Ash 

10-99 

69-50 

5-84 

0-42 

13-25 

12-70 

55-80 

6-5.3 

28-li 

57-00 
29-04 
15-46 
24-74 

11-00 
11-54 

37-94 
36-45 

15-50 

31-38 
0-16 

3-80 

3-62 

8-69 

10-54 

Many  preparations  (chiefly  of  beef)  are  now  made  by  partially  digesting  the 
meat,  and  drying  more  or  less  completely.  The  preparation  is  in  some  cases 
mixed  with  carbohydrates.  It  will  suffice  to  mention  a  few  of  these  articles  : 
they  are  chiefly  used  for  invalids.     Darby's  Fluid  Meat,  a  liquid  preparation, 


'   Bee  Konig,  op.  cit.  i.  232  and  242. 


FOOD  449 

contains  30"70  per  cent,  of  peptone.  It  has  an  agreeable  odour  and  aroma. 
Carnrick's  Beef  Peptonoids  is  a  dried  powdered  mixture  of  digested  beef  and 
gluten  and  concentrated  milk.  It  contains  56*62  per  cent,  of  albumose  (pro- 
pepton),  7*11  per  cent,  of  peptone,'  with  5*5  per  cent,  of  salts.  Kemmerich's 
Fleischpepton  contains  14-56  per  cent,  of  albumose  and  32-57  per  cent,  of 
peptone,  while  Koch's  somewhat  similar  preparation  contains  15"95  per  cent, 
of  albumose  and  18*83  per  cent,  of  peptone. 

Beef -tea  is  usually  made  from  the  skin  or  breast  of  beef,  but  the  best  kind 
is  made  from  beefsteak.  In  its  preparation,  the  beef  must  be  freed  from 
tendon  and  any  excess  of  fat,  and  cut  into  small  pieces.  It  is  then  covered 
with  cold  water,  salt  added,  and  placed  on  the  hob  for  two  to  three  hours  ;  hot 
water  is  added,  and  the  mixture  allowed  to  heat  gently  from  one  to  one  and  a 
half  hours,  the  temperature  never  being  raised  to  the  boiling  point.  By  this 
means  most  of  the  salts  and  extractives  are  dissolved  out  of  the  meat,  together 
with  some  gelatine  and  fat. 

Beef- tea  is  not  a  proteid  food,  since  it  contains  only  a  trace  of  other  proteid 
besides  gelatine  ;  most  of  the  myosin  is  coagulated  during  the  preparation, 
and  in  order  to  utilise  this  myosin  as  food,  it  is  best  to  take  the  '  dregs  '  of 
the  beef-tea  as  well  as  the  Uquid.  Beef-tea  is  a  salty  food,  containing  the 
sodium  chloride  from  the  blood  and  the  interstitial  liquid  of  the  muscle,  and 
the  potassium  and  phosphates  from  the  muscle  fibre  itself  (see  p.  442).  It  is 
also  a  stimulant  to  the  nervous  system,  and  a  restorative  of  muscular  energy. 
These  effects  are  ascribed  to  the  extractives,  and  chiefly  to  creatine,  which  is 
in  larger  amount  than  the  other  extractives.  The  mineral  salts,  however,  may 
participate  in  this  stimulant  effect.  Soups  made  without  the  addition  of 
vegetables  have  a  composition  and  action  similar  to  that  of  beef- tea  ;  if  bones 
are  used  in  their  preparation,  they  contain  more  gelatine  and  salts  than  ordi- 
nary beef-tea. 

Liehig's  Extract  of  Meat  (Extractum  Carnis)  is  prepared  by  freeing  the 
meat  from  fat  and  tendon,  and  applying  a  moderate  heat ;  the  juice  exuding  is 
the  extract.  Sufficient  heat  is  not  employed  to  change  the  collagen  into 
gelatine,  so  that  the  extract  consists  almost  solely  of  salts  and  extractives, 
creatin,  and  the  other  nitrogenous  non-proteid  bodies  present  in  muscle. 
Liebig's  Extract  is  thus  not  a  proteid  food,  but  is  a  salty  food,  and  a  powerful 
stimulant  Uke  beef-tea.    It  is  a  useful  agent  to  restore  mental  or  bodily  activity. 

Extractum  Carnis  is  also  made  by  pressure  alone,  without  the  appUcation  of 
heat.  Many  other  preparations  are  in  the  market,  concentrated  forms  of  beef- 
tea.  They  do  not  keep  like  Liebig's  Extract,  but  they  are  more  pleasant  to  take. 

VEGETABLE  FOODS 

Articles  of  diet  derived  from  the  various  parts  of  plants,  seed,  stem,  root, 
leaves,  &c.,  have  three  chief  functions  to  perform.  First,  they  are  the  chief 
source  (in  fact  the  only  practical  source)  of  the  carbohydrate  food  of  the 
animal ;  for  although,  as  we  have  seen,  glycogen  is  a  constituent  of  meat  and 
of  liver,  it  is  in  too  small  quantity  to  supply  the  needs  of  the  economy  : 
therefore  it  is  necessary  to  consume  vegetable  starches  and  sugars.  Secondly, 
they  supply  a  large  amount  of  salts  to  the  body — phosphates,  calcium, 
magnesium,  potassium,  and  iron,  while  sodium  and  chlorides  are  present  in 
deficient  quantity,  as  has  already  been  pomted  out.  Owing  to  the  amount 
of  water  they  take  up  during  cooking,  they  also  supply  a  large  quantity  of 

'  The  analysis  was  performed  before  the  recent  researches  of  Kiihne  and  Chittenden  on 
albumoses;  hence  most  of  this  peptone  must  be  considered  as  albumose.  The  same 
remark  applies  to  other  analyses  of  '  peptone '  preparations. 

VOL.     I.  QQ 


450  HYGIENE 

■water  to  the  organism.  Uncooked  fruits  also  perform  this  fmiction.  Thirdly, 
they  are  antiscorbutic.  This  action  in  this  respect  varies  in  the  different 
vegetable  foods,  and  it  is  not  known  what  particular  constituent  or  con- 
stituents possess  the  effect  of  preventing  and  of  curing  scurvy.  This  anti- 
scorbutic action  is  of  great  importance  in  considering  vegetable  foods. 

Stress  has  been  laid  under  the  iirst  heading  to  the  fact  that  vegetable 
food  is  the  chief  source  of  the  carbohydrate  ingested.  To  a  less  extent  they 
are  the  source  of  proteid  food.  As  we  shall  see,  the  Leguminosae  are  rich  in 
proteids,  but,  as  has  already  been  pointed  out,  the  mixture  of  proteids,  carbo- 
hydrates, cellulose,  and  salts,  present  in  the  leguminous  foods  does  not  form 
a  combination  in  which  the  proteids  are  most  easily  assimilable  by  the 
organism.  The  proteids  of  the  cereals,  and  especially  of  wheaten  flour  when 
made  into  bread,  are  not  to  be  forgotten  as  of  great  importance. 

Vegetable  fats  are  of  secondary  importance  as  food.  Most  of  the  vegetable 
foods  contain  but  little  fat,  and  this  is  not  so  digestible  as  animal  fat.  The 
fatty  vegetable  foods  (chiefly  varieties  of  oats)  are  not  in  general  use  as  foods 
among  civilised  races.  Olive  oil  (with  its  common  adulteration,  cotton-seed 
oil)  does  not  form  an  important  constituent  of  dietaries.  The  fat  of  diets 
is  usually  derived  from  animals — butter,  &c. 

Preparation  of  Vegetable  Food.— The  seeds  of  the  cereals,  and  of  some  of 
the  Leguminoste  after  removing  the  outer  coats,  are  ground  into  flours.  The 
advantages  of  this  mode  of  preparation  are  plain.  It  removes  a  large  quantity 
of  cellulose,  which  is  not  only  indigestible,  but  prevents  the  complete  digestion 
and  absorption  of  the  foodstuffs,  and  it  renders  the  food-article  more  easily 
cooked  and  digested,  owing  to  the  fine  division  and  the  ease  with  which  the 
starch  grains  are  acted  upon  by  boiling  water  (see  pp.  418  et  seq.iov  cooking  and 
digestibility  of  vegetable  foods).  During  the  process  of  milling  there  is  a  slight 
loss  in  the  percentage  of  proteid,  and  a  greater  loss  of  salts  with  a  corre- 
sponduig  increase  in  the  percentage  of  carbohydrates  (see  tables  following). 
In  the  case  of  wheaten  flour,  the  better  the  milling,  the  less  cellulose  there 
is  present,  and  the  less  salts,  while  the  whiteness  of  the  flour  increases, 
although  the  colour  to  some  extent  depends  on  the  natural  colour  of  tlie 
varieties  of  wheat. 

Wheaten  flour  undergoes  a  further  preparation  into  bread ;  rye  flour  is 
also  made  into  bread  ;  millet  and  buckwheat  yield  an  inferior  kind  of  '  bread.' 

General  Composition  of  Vegetable  Foods ;  Characters  of  the  Foodstuffs 

1.  Proteids. — The  characters  of  the  vegetable  proteids  have  already  been 
partly  discussed.  The  researches  of  Vines,  the  author,  and  others  of  late 
years  have  tended  to  show  that  in  the  seeds  of  plants  the  two  chief  proteids 
present  are  of  the  nature  of  a  globulin  and  of  albumoses.  The  legumin  and 
conglutin  of  leguminous  seeds,  Vines  considers,  are  artificial  products  of  the 
action  on  the  globulin  of  the  dilute  potash  solution  used  in  extracting.  This 
point  is,  however,  not  quite  settled.  Some  of  the  vegetable  proteids  exist  in 
a  crystalline  form  ;  a  crystalline  form  of  vegetable  vitellin  has  been  described 
by  Maschka,^  Weyl,  Schmiedeberg,^  and  others.  The  aleurone  grains  found 
in  the  cells  of  plants  consist  partly  of  crystalline  proteids  (Vines).  It 
may  be  pointed  out  again  here  that  the  nutritive  value  of  the  proteids  of 
leguminous  seeds  is  probably  equal  to  that  of  animal  proteids  (in  meat,  eggs, 
&c.),  as  the  experiments  of  Eutgers  (previously  quoted)  and  others  have 

'  Journ.  prakt.  Chem.  Bd.  Ixxiv.  p.  43G. 

-  Zeit.  fiir  physiol.  Chcmic,  Bd.  i.  p.  205.  See  also  Jcncrn.  prakt.  Chem.  Bd.  cxxxi. 
pp.  105,  481. 


FOOD  451 

shown ;  but  that  the  admixture  with  other  foodstuffs  and  with  cellulose  found 
in  the  seeds  renders  them  less  serviceable  as  proteid  foods  than  meat  from 
animals. 

The  most  important  vegetable  proteid  is  the  gluten  of  wheat,  owing  to 
the  fact  that  bread  is  a  universal  article  of  diet  and  a  necessity  of  ordinary 
hfe.  Gluten  is  not  present  in  wheaten  flour,  but  is  formed  from  the  globulin 
and  albumose  present  by  the  action  of  water.'  It  is  composed  of  gluten 
fibrin,  derived  from  the  globulin,  and  of  insoluble  albumose,  derived^  from 
the  soluble  form  in  the  flour.  This  insoluble  albumose  probably  corresponds 
to  Eitthausen's  gluten-casein  :  the  occurrence  of  this  observer's  gliadin  and 
mucedin  was  not  confirmed  by  the  author.  Some  of  the  reactions  of  gluten 
are  important  from  a  dietetic  point  of  view.  Boiling  water,  for  exa'rnple, 
coagulates  the  gluten-fibrin  and  dissolves  out  part  of  the  albumose  ;  while 
uncoagulated  gluten  is  completely  soluble  in  dilute  acids  and  alkalies, 
although  with  some  difficulty.  This  solubility,  with  its  ready  digestibihty 
by  pepsin-hydrochloric  acid  and  by  pancreatic  juice,  renders  gluten  a  valuable 
proteid  food.  Eye  flour  yields  a  gluten  with  water,  but  to  a  less  extent  than 
wheaten  flour,  and  it  cannot  be  obtained  readily  by  washing,  like  wheat-gluten. 

2.  Fats. — The  fats  of  the  vegetable  foods  in  ordinary  use  are  quite  unim- 
portant from  a  nutritive  point  of  view,  being  present  in  small,  and  even 
minute  quantity. 

3.  Carbohydrates.— ^ioxckes,  dextrines  (gums),  and  sugars  are  found  in 
vegetable  foods.  In  the  seeds  of  cereals  and  Leguminosse  the  starch  is  the 
<3hief  carbohydrate,  although  dextrines  and  sugars  are  also  present.  In  some 
vegetable  foods,  sugar  in  the  form  of  cane-sugar  (sugar-cane,  beet)  or  in  the 
form  of  glucose  (various  ripe  fruits)  is  the  only  carbohydrate  present  in 
quantity.  Dextrine  is  usually  present  in  small  quantity  with  the  starch  (see 
special  section).  The  starches  vary  greatly  in  physical  characteristics,  in 
the  size,  form,  and  structure  of  the  starch  grain. 

Commercial  Starches.— The  average  percentage  composition  of  the  starches 
found  in  commerce  is  16-04  of  water,  1-18  of  proteid,  0-06  of  fat,  82-13  of 
carbohydrate,  0-13  of  cellulose,  and  0-86  of  salts.  Of  such  an  average  com- 
position are  arrowroot,  tapioca,  sago,  potato  starch,  and  maize  starch. 

Arroioroot  is  obtained  from  different  sources.  The  West  Indian  is  obtained 
from  Maranta  arundinacea,  and  is  white  and  granulated  in  lumps.  Forms 
of  arrowroot  are  also  obtained  from  Curcuma,  Jatropha  Manihot  (Eio 
arrowroot,  yielding  tapioca),  the  arum  (Portland  sago),  and  Canna  edulis 
(Tous-les-mois).  All  these  preparations  of  starch  readily  form  a  clear  jelly 
on  cooling  after  heating  with  water. 

The  chief  adulteration  of  true  arrowroot  (Maranta  and  Tous-les-mois)  is 
with  potato,  sago,  and  tapioca. 

Tapioca  is  made  from  the  pith  of  Jatropha  Manihot  (the  cassava).  It  is 
adulterated  with  potato  starch,  and  sago. 

Sago  is  obtained  from  the  uaterior  of  the  sago-palm  {Sagus  farinifera). 
The  commercial  varieties  are  '  common '  or  '  pearl.'  The  starch  is  soluble  in 
cold  and  hot  water. 

Potato  starch  is  the  usual  adulteration. 

Identification  of  the  Starches  by  the  Microscope 

Adulterations  of  the  starches  by  other  varieties  is  detected  best  by  the 
microscope.     Owing  to  the  characteristic  form  of  the  starch  granules  in  such 

'  Weyl  and  Bischoff,  Ber.  d.  deutscJi.  Chem.  Gesellsch.  Bd.  xiii.  1880,  p.  367 ;  Sidney 
Martm,  Brit.  Med.  Journal,  II.  1886. 

gg2 


452 


HYGIENE 


varieties,  the  adulteration  of  the  pure  starches  just  discussed  or  of  the  dif- 
ferent flours  may  be  detected.  Wheaten  flour,  being  the  most  important,  is 
the  flour  usually  adulterated. 

The  structure  of  the  starch  grain  has  already  been  described  (p.  422). 
Each  grain  is  laminated  to  a  greater  or  less  extent,  and  has  a  point  round 
which  the  laminfe  are  ranged  ;  this  point,  which  is  variously  shaped,  is  the 
hilum.  The  lamination,  the  position  of  the  hilum,  the  shape  of  the  grain, 
the  character  of  the  contour,  and  the  size  all  serve  in  the  identification  of 
the  varieties. 

Starch  grains  may  be  divided  into  two  groups:  (1)  a  group  in  which 
the  contour  is  even,  containing  potato  starch,  most  of  the  varieties  of  arrow- 
root, beau,  pea,  wheat,  barley,  and  rye  starch  ;  (2)  a  group  in  which  the  con- 
tour is  facetted  either  partially,  as  in  sago  and  tapioca,  or  completely,  as  in 
rice,  maize,  and  oats. 

1.  Starch  Grains  with  even  Contour. — (a)  Potato  starch  may  be  taken 
as  the  type.  The  largest  grains  average  0-0G52  millimetre  in  the  longest 
diameter  ;  the  smaller  grains  0'024;  millimetre.'  The  grains  are  pyriform 
in  shape,  with  an  eccentric  hilum  (at  the  small  end  of  the  grain),  and  the 
lamination  is  well  marked  (see  fig.  O-l).- 

(b)  Bermuda  Arroivroot. — Large  grains,  0*044  millimetre  ;  medium-sized 
grains,  0*02  millimetre ;  and  smallest  grains,  0*012  millimetre  in  the  longest 
diameter. 


Fig.  94. — Potato  starch. 


Fig.  95. — Bermuda  arrowroot         Fig.  96. — St.  Vincent  arrowroot 
starch.  starch. 


The  grains  are  ovoid,  with  the  hilum  at  the  larger  end,  the  hilum  being 
a  dot,  a  slit,  or  crucial  (see  fig.  95).  The  lamination  is  well  marked.  The 
grain  is  frequently  beaked. 

St.  Vincent  Arroioroot. — Large  grains,  0"04o6  millimetre  ;  medium-sized, 
0'028  ;  and  smallest,  0"012.  The  grains  have  the  same  character  as  those  of 
Bermuda  arrowroot,  and  it  is  almost  impossible  to  distinguish  them  (see 
fig.  96). 

Tous-les-Mois  arroivroot  has  grains  like  potato  starch,  but  they  are 
much  larger.  The  hilum  at  the  smaller  end  of  the  grain  distinguishes  tous- 
les-mois  from  Bermuda  and  St.  Vincent  arrowroot. 

Curcuma  arroivroot  has  large  oblong  grains,  well  laminated  ;  the  hilum 
is  at  the  smaller  end  of  the  grain. 

(c)  The  grains  of  beans  and  2y^tts  are  oval  or  reniform,  with  a  longitudinal 
hilum,  which  is  irregvilar  in  bean  starch,  but  more  regular  in  pea  starch. 
Lamination  is  indistinct. 

Pea-starch  grains  {Pisum  sativum),  largest  grains,  0*044  millimetre  in 
longest  diameter  ;  medium-sized  grains,  0'028  millimetre  ;  and  smallest,  0*01 
millimetre  (fig.  97). 

'  These  measurements  are  the  average  of  5  to  10  grains  ;  they  give  a  good  idea  of  the 
difference  of  size  of  grains  in  the  different  starches.  The  measurements  are  in  all  cases  of 
the  longest  diameter. 

-  All  the  figures  are  drawn  under  the  magnifying  power  of  Hartnack,  Oc.  7,  Obj.  .3. 


FOOD 


453 


Bean-starch  grains  (haricot  bean,  Phaseohis  vulgaris).  Average  longest 
■diameter,  0*044  millimetre  (fig.  98). 

(d)  The  starch  grains  of  loheat  and  barley  cannot  be  distinguished  under 
the  microscope  ;  barley,  however,  contains  many  medium-sized  grains,  while 
wheat  contains  only  large  and  very  small  grains  (see  figs.  99  and  100). 


Pig.  97.— Pea  starch. 


Fig.  98. — Bean  starch  {Phaseolus 
vulgaris). 


The  grains  are  round  and  oval,  Avith  a  central  hilum,  slit-like,  and  some- 
times star-shaped  in  the  wheat  (see  fig.  100).     Lamination  is  very  faint. 

Wheat  Starch  Grains. — Lai-gest,  0-032  millimetre  in  longest  diameter ; 
smallest,  0-004  to  0-008  millimetre. 


Pig.  100.— Wheat  starch. 


Pig.  99.— Barley  starch. 


Pig.  101. — Rye  starch. 
a,  crushed  grain. 


0-02 


Barley  Starch  Grains. — Largest,  0-03  millimetre  ;  medium-sized, 
smallest,  0-004  to  0-008  millimetre  in  longest  diameter. 

The  starch  grains  of  rye  are  very  similar  to  those  of  wheat  and  barley  ; 
the  contour  is,  however,  spherical,  and  the  hilum  frequently  star-shaped  (see 
fig.  101),  especially  in  the  largest  grains.  The  smallest  grains  are  0-004 
millimetre  in  diameter.  The  medium-sized  are  0-02  milhmetre,  and  the 
largest,  0*04  miUimetre  in  diameter.    The  presence  of  these  large  grains  with 


Pig.  102.— Sago  starch. 


Pig.  103. — Tapioca  starch. 


star-shaped  hilus  distmguishes  rye  from  barley ;  the  presence  of  numerous 
medium-sized  grains  and  of  many  grains  with  star-shaped  hilus  distinguishes 
rye  from  wheat. 

2.  Starch  Grains  ivith  a  facetted  Contotor.— In  sago  and  tapioca,  the  grains 
are  partially  facetted  (see  figs.  102  and  103).    The  grains  of  sago  are  large,  the 


454 


HYGIENE 


hilmn  often  cavernous,  and  there  is  a  liollow  in  the  centre  of  the  grain. 
Lamination  is  imperfect  and  irregular,  bize  of  largest  grains,  0'059  milli- 
metre ;  medium -sized,  0-082  millimetre  in  the  longest  diameter. 

Tapioca  is  only  to  be  distinguished  from  sago  by  the  size  of  the  starch 
grains ;  these  are  about  one-third  the  size  of  the  largest  grains  of  sago,  i.e. 
about  0-022  millimetre  in  the  longest  diameter  (fig.  108). 

The  starch  grains  of  maize,  oats,  and  rice  are  completely  facetted,  and  are 
readily  distinguished  under  the  microscope.  The  points  they  have  in  common 
are  that  they  are  completely  facetted,  and  that  lamination  is  very  indistinct 
or  absent.  In  maize  the  facets  are  the  most  perfect,  the  grain  being  like  a 
disc  or  half  a  tetrahedron  ;  the  hilum  is  distinct,  stellate,  sometimes  a 
mere  dot,  sometimes  cavernous  (see  fig.  104).  The  diameter  of  the  grains 
averages  0-028  millimetre. 

In  rice  (fig.  105)  and  oats  the  grains  are  very  small,  in  the  former  0*006 
milhmetro  in  diameter,  in  the  latter  twice  the  size,  viz.  0-012  millimetre. 


Fig.  104. — Maize  starch 
(Indian  com). 


Fig.  105. — Eice  starch. 


Fig.  100.— Oat  starch. 


Apart  from  the  size,  oat-  starch  grains  are  readily  distinguished  from  rice  by 
their  aggregation  into  spherical  clumps  (see  fig.  106).  They  are  both  dis- 
tinguished from  maize  by  the  size  of  the  grain,  and  by  the  fact  that  in  very 
few  grains  of  oat  and  rice  starch  can  a  hilum  be  seen. 

Sugars. — The  two  chief  varieties  of  sugar  found  in  commerce  are  cane- 
sugar  from  the  sugar-cane  {Saccharum  officinarum),  and  beet-sugar  from 
Beta  vulgaris. 

White  cane-sugar  contains,  in  100  parts,  98-38  parts  of  saccharose,  1-78 
of  dextrose,  0-85  of  proteid,  0-30  of  gum  and  vegetable  acids,  O'Ql  of  ex- 
tractives, 0-76  of  salts,  and  2-16  of  water. 

Beet-sugar  contains,  in  100  parts,  94-42  parts  of  saccharose,  0-21  of  invert- 
sugar,  3-44  of  various  substances,  and  1-93  of  water. 

The  colour  of  brown  sugar  is  due  to  invert-sugar,  of  which  there  is  4-5 
per  cent,  present.  Brown  sugar  also  contains  more  water  than  white ;  on 
the  average  4-6  per  cent,  is  present,  but  as  much  as  10  per  cent,  may  be 
found  in  coarse  brown  sugar. 

Honey  dijffers  from  ordinary  sugar  in  containing  more  invert-sugar 
(dextrose  and  lasvulose)  than  saccharose.  The  composition  varies  greatly, 
but  on  an  average,  in  100  parts,  there  are  72-88  parts  of  invert-sugar 
(consisting  of  38-65  lacculose  and  84-48  dextrose),  1-76  of  saccharose,  0-22 
of  dextrine,  0-71  of  wax,  0-76  of  proteid,  2-82  of  non-saccharine  sub- 
stances, 0-25  of  ash,  0-028  of  phosphoric  acid,  and  20-60  parts  of  water.  The 
total  invert-sugar  may  be  as  low  as  64-10  per  cent.,  and  as  high  as  79-37 
per  cent.  Lsevulose  is,  however,  always  in  greater  proportion  than 
dextrose. 

Honey  is  adulterated  with  cane-sugar,  with  sugar  made  from  starch,  and 
with  inert  matter.    . 

Salts. — These  will  be  considered  under  the  special  headings  of  foods. 
As  has  already  been  pointed  out,  potassium  and  phosphates  are  in  excess 


FOOD  4^5 

over  sodium  and  chlorides,  showing  the  necessity  of  common  salt  to  vege- 
table feeders.  Iron  is  an  important  constituent  of  the  salts  of  vegetable 
foods  ;  in  white  wheat,  for  example,  phosphate  of  iron  forms  0-3 1  per  cent, 
of  the  ash,  while  in  the  Peruvian  quinoa  seeds  it  is  present  in  the  proportion 
of  0*75  of  the  whole  seed  (quoted  by  Parkes  ^). 

A  rough  but  useful  classification  of  vegetable  foods  may  be  made  accord- 
ing as  the  organic  foodstuffs  or  the  inorganic  are  the  chief  constituents 
present. 

1.  In  one  class,  for  example,  there  are  the  food  grains,  including  the 
cereals,  in  which  the  proteids  are  present  in  the  proportion  of  about  10  per 
cent.,  while  the  carbohydrates  are  from  65  to  70  per  cent.  These  foods  are 
chiefly  carbohydrate  foods,  to  a  less  extent  proteid  foods.  Edible  chestnuts 
also  belong  to  this  class. 

2.  In  another  class  the  seeds  of  Leguminosae  are  included.  In  these  the 
proteids  are  from  20  to  25  per  cent,  (sometimes  over  30  per  cent,  in  Soja 
beans),  while  the  carbohydrates  are  from  46  to  69  per  cent.  This  class  then 
includes  vegetable  products  which  are  eminently  proteid,  as  loell  as  carbo- 
hydrate foods. 

3.  A  third  class  contains  members,  such  as  the  potato,  in  which  the  pro- 
teid is  insignificant  in  quantity,  Avhile  the  carbohydrates  are  fairly  abundant 
(20  per  cent.)  To  this  class  would  pre-eminently  belong  the  commercial  pre- 
parations of  starch,  such  as  arrowroot,  tapioca,  and  sago. 

4.  Some  vegetables,  as  the  beet  and  ripe  fruits,  are  also  carbohydrate 
foods  ;  but  they  have  a  more  important  function  than  this  to  perform,  viz. 
that  of  supplying  vegetable  acids  and  salts  to  the  organism.  In  this  way 
foods,  such  as  cabbage,  turnips,  carrots,  &c.,  act  as  antiscorbutics. 


CLASS   I.     THE    CEREALS 

The  cereals  belong  to  the  first  class  of  vegetable  foods,  those  which  are 
chiefly  serviceable  as  yielding  carbohydrates,  while  to  a  less  extent  they  are 
proteid  foods. 

To  the  cereals  belong  wheat,  barley,  oats,  rice,  rye,  maize,  and  millet. 
Buckwheat  may  also  be  included.  By  far  the  most  important  of  these  is 
wheat,  as  yielding  bread,  but  in  some  countries  other  cereals  are  also  of 
great  importance — in  Scotland  oats,  in  India  rice  and  millet,  and  in  the 
Spanish- speaking  countries  of  America  maize-cakes  take  the  place  of  bread, 
which  is  almost  unknown. 

The  preparation  which  these  grains  undergo  and  the  effect  it  has  on  the 
percentage  composition  have  already  been  discussed  (p.  450).  This  effect  is 
evident  by  referring  to  the  tables  following.  Bread  is  made  chiefly  from 
wheaten  flour,  but  inferior  kinds  are  also  made  from  rye,  millet,  and  buck- 
wheat. 


Wheat  {Triticum  vulgare  et  sp.  var.) 

The  wheat  grain  is  surrounded  by  four  coats,  the  outermost  of  which  is 
cuticular  and  hairy  ;  the  next  coat  is  composed  of  rounded  cells  ;  the  third 
coat  is  almost  hyaline  ;  and  the  internal  coat  is  also  very  thin.  The  second 
coat  is  the  only  conspicuous  one.     Within  the  innermost  coat  is  the  wheat 

'  Hygiene,  p.  286. 


456 


HYGIENE 


grain  proper,  which  contains  the  starch,  fat,  proteid,  and  salts  of  the  flour. 
In  the  process  of  miUing  the  coats  are  removed  as  far  as  possible,  being 
separated  as  bran  ;  in  the  so-called  wholemeal  the  whole  grain  is  milled. 

Percentage  Composition  of  Cereal  Grains  and  of  Flours 


Carbo- 

Proportion of 



Water 

Proteid 

Fat 

Cellulose 

Ash 

nit.  to  non- 

hydrates 

nit,  foolstufl'p 

1.  Wheat  : 

Grain    (average    of   948 

analyses  of  all  countries) 

13-37 

12-04 

1-85 

68-65 

2-31 

1-78 

— 

Flour,  fine 

13-37 

10-21 

0-94 

74-71 

0-29 

0-48 

1  :7-4 

„     coarse  . 

12-81 

12-06 

1-36 

71-83' 

0-98 

0-96 

1  :  5-98 

„     wholemeal       (At- 

water) 

13-00 

11-70 

1-70 

69-90 

1-90 

1-80 

1  :6-l 

2.  Barley: 

Grain  (shelled,  average)  . 

14-05 

9-66 

1-93 

66-99 

4-95 

2-42 

— 

Flour      .... 

14-83 

11-38 

1-53 

71-22- 

0-45 

0-59 

1  :  6-4 

3.  Oats: 

Grain  (shelleil) 

12-11 

10-66 

4-99 

58-37 

10-58 

3-29 

— 

Meal  (line) 

9-65 

13-44 

5-92 

67-01^ 

1-86 

2-12 

1  :5-4 

4.  Eice: 

Shelled    .... 

12-58 

6-73 

0-88 

78-48' 

0-51 

0-82 

1  :  11-8 

5.  Hte  : 

Grain  (shelled,  average) 

13-37 

10-81 

1-77 

70-21 

1-78 

2-06 

— 

„       German 

13-37 

11-52 

1-84 

68-88 

2-45 

l-'.)4 

— 

Flour      .... 

13-71 

11-57 

2-08 

69-61^ 

1-59 

1-44 

1  :  6-2 

6.  Maize  (Indian  corn) : 

Grain  (average) 

13-35 

9-45 

4-29 

69-33 

2-29 

1-29 

— 

Meal        .... 

14-21 

9-65 

3-80 

69-55 

1-46 

1-33 

1  :7-6 

(For  Millet  and  Buckwheat  see  p.  468.) 

Wheateii  flour,  as  just  stated,  is  of  two  kinds,  the  one  ordinarily  used 
being  white,  the  other,  wholemeal,  being  of  a  dark  colour,  owing  to  the  ad- 
mixture of  bran. 

In  the  market  there  are  several  varieties,  according  to  the  completeness 
of  the  milling — separation  of  the  coats  and  grinding  of  the  grain.  The  most 
highly  milled  flours  are  the  whitest,  and  contain  least  bran  and  least  cellu- 
lose ;  as  has  been  pointed  out,  they  lose  in  the  process  some  proteid  and 
some  salts,  but  this  loss  is  more  than  compensated  for  by  the  fineness  of  the 
bread  prepared  from  it.  The  chief  flours  in  the  market  are  in  the  order  of 
their  excellence  (fineness  and  whiteness),  Vienna  whites,  best  whites,  best 
households,  second  households,  and  other  flours  inferior  in  quality.  There 
are  also  brown  meal  and  whole  meal. 

We  have  already  stated  that  the  two  proteids  present  in  flour  are  a 
globulin  and  an  albumose,  and  that  gluten  is  formed  from  these  by  the  action 
of  water.  All  the  globulin  and  albumose  is  not  transformed  into  gluten — 
some  remains  dissolved  in  the  water  with  which  the  flour  is  washed."  For 
the  proportion  of  gluten  see  p.  4G1. 

The  amount  of  gluten  obtainable  is  a  test  of  the  quality  of  the  flour  as 
regards  proteid  and  its  capacity  for  making  bread.  In  bad  wheat  (due  to 
bad  seasons,  &c.)  very  little  gluten  may  be  obtainable  from  the  flour,  the 

'  The  carbohydrates  are  composed  of  starch  66-28  per  cent.,  dextrine  4-00  per  cent.,  and 
BUgar  1-86  per  cent. 

'  Composed  of  starch  61-59  per  cent.,  dextrine  6-52,  and  sugar  3-11  per  cent. 

^  Starch  59-39  per  cent.,  dextrine  3-08  per  cent.,  sugar  2-26  per  cent. 

*  A  small  proportion  of  dextrine  and  a  trace  of  sugar  (Pillitz). 

'  Starch  58-61  per  cent.,  dextrine  7-16  per  cent.,  sugar  3-80  per  cent. 

•^  This  is  often  erroneously  referred  to  as  '  albumen  '  in  works  on  food,  and  gluten  is 
6poken  of  as  a  constituent  of  flour. 


FOOD 


457 


proteids  being  in  the  form  of  '  soluble  albuminoids,'  as  they  are  often  called, 
and  thus  remain  dissolved  in  the  water  used  in  washing  the  flour  without 
yielding  gluten.  The  better  the  flour  the  less  the  '  soluble  albuminoids ' 
yielded  by  water  (see  Examination  of  Flouk,  p.  4G1).  Why  they  should  not 
form  gluten  is  not  known,  any  more  than  why  barley,  which,  according  to  my 
researches,  contains  proteids  of  the  same  character  as  wheat,  should  not  yield 
gluten  at  all.  Some  wheats  (called  hard)  yield  much  gluten ;  from  such 
macaroni  is  made.  Soft  wheats  contain  less  gluten  than  the  hard,  and  more 
starch.  The  starch  presents  the  characters  previously  mentioned  (p.  453). 
Some  dextrine  and  sugar  are  also  present  (Table,  p.  456).  The  salts  consist 
chiefly  of  phosphates  and  potassium  and  magnesium. 

Percentage  Composition  of  Wheat-grain  Ash  • 


Lawes  and  Gilbert  Way  and  Ogston 


Phosphoric  acid   . 
Phosphate  of  iron 
Potash . 
Soda     . 
Magnesia 
Lime    . 
Sulphuric  acid 
Carbonic  acid 
Chlorine 
Silica,  &c.     . 

Total 


49-68 

45-01 

2-36 

0-82 

29-35 

31-44 

1-12 

2-71 

10-70 

12-36 

3-40 

3-52 



0-34 



0-02 

0-13 

0-13 

2-47 

3-67 

99-21 


100-02 


Wheat  as  a  Food. — In  fine  flour  the  proportion  of  nitrogenous  to  non- 
nitrogenous  organic  foodstuffs  is  as  1  to  7-4 ;  the  proteids  are  therefore 
deficient.  Wheat  is  therefore  chiefly  a  carbohydrate  food,  although  the  pro- 
teid  constituents  are  very  nutritious.  When  made  into  bread  it  is  a  food 
which  may  be  eaten  for  any  length  of  time,  since  it  never  cloys  ;  but,  as  seen 
from  what  has  been  said,  it  is  deficient  in  two  foodstuff's — fat  and  common 
salt.  The  addition  of  salt  to  the  bread  (in  the  making)  and  the  eating  with 
butter  are  two  empirical  discoveries  of  mankind  which  have  a  very  rational 
basis.  '  Brown. '  bread  is  made  from  white  flour  (often  not  of  the  best)  mixed 
with  varying  proportions  of  bran.  It  is  far  below  white  bread  as  a  food, 
owing  to  the  admixture  of  coarse  bran  and  its  aperient  action. 

Of  late  years  it  has  been  proposed  to  include  the  whole  of  the  wheaten 
grain  in  the  making  of  bread,  wholemeal  yielding  Avholemeal  bread.  The 
advantages  claimed  for  this  process  are  that  the  bread  is  thereby  rendered 
more  nutritious  ;  there  are  more  proteid  foodstuffs  and  more  salts  in  the 
bread.  The  exact  gain  depends,  of  course,  on  the  quahty  of  the  wheat 
originally  used.  If  we  take  bran  as  forming  16  parts  of  the  grain,  we  have 
an  addition  of,  on  the  average,  0-7  per  cent,  of  proteid,  and  0"16  per  cent,  of 
salts.  The  disadvantages  of  wholemeal  bread  are  first  its  dark  colour,  and 
the  fact  that  the  gain  in  proteid  and  salts  is  accompanied  by  an  admixture 
of  cellulose.  This  indigestible  cellulose,  whether  the  flour  is  finely  milled 
or  not,  is  not  only  an  irritant  to  the  intestines  (as  shown  by  its  stimulating 
peristalsis),  and  especially  so  in  disease  of  the  alimentary  tract,  but  it 
also  diminishes  the  absorption  of  the  digestible  foodstuffs  ;  a  fact  which  has 
already  been  insisted  upon.  These  effects  of  cellulose  more  than  counter- 
balance the  gain  in  proteid  and  salts.     Salts  in  abundance  are  obtained  from 


'  Quoted   by  Dr.  C.  Graham,  '  Chemistry   of   Bread-making,'    lecture   at  the   Health 
Exhibition,  1884. 


458  HYGIENE 

many  foods  besides  flour,  and  bread  is  not,  as  has  been  stated,  a  pre-eminently 
proteid  food.  It  seems  wiser,  tberefore,  to  adhere  to  the  tradition  of  centuries., 
and  finely  mill  the  grain  so  as  to  obtain  white  flour  and  white  bread. 

Preparations  of  Wheaten  Flour 
Of  the  preparations  of  flour,  bread  is  the  most  important :  of  less  import- 
ance are  biscuits,  macaroni,  and  vermicelli. 

1.  Bread 

The  best  bread  is  made  from  white  wheaten  flour.  In  times  of  famine  or 
war  other  starchy  foods  are  added  to  the  flour,  to  make  up  the  weight  of  the 
loaf ;  these  starchy  foods  are  rice,  barley,  oats,  rye,  maize,  millet,  peas,  and 
buckwheat.  Under  ordinary  conditions,  these  additions  are  regarded  as 
adulterations,  under  which  heading  they  will  be  considered  (p.  4G1). 

The  processes  for  making  bread  are  various.  The  first  process,  the  origin 
of  which  is  hidden  in  prehistoric  times,  consisted  in  simply  mixing  the  flour 
with  water,  and  baking.  This  process  is  still  used  in  Spain,  in  India  (making 
'  chupatty  ' ),  and  in  Austraha  ( making '  damper  ') ;  leaven  was  then  discovered, 
and  is  now  used  in  some  countries  in  the  North  of  Europe.  Leaven  is  dough, 
with  or  without  an  admixture  of  salt  and  boiled  potatoes,  allowed  to  stand 
exposed  to  the  air,  until  decomposition  commences.  This  decomposition  is 
produced  by  a  ferment  action  on  the  starch,  whereby  alcohol  and  carbonic  acid 
gas  are  formed.  The  leaven  acts  the  part  of  the  ferment  (presently  to  be 
described)  in  the  ordinary  making  of  bread.  The  modern  process  of  bread- 
making  consists  in  the  use  of  yeast  as  a  ferment. 

(a)  Bread-making  by  Means  of  Yeast. — The  London  system  is  a  long 
process  with  three  stages :  ' — 

1.  The  preparation  of  the  'ferment.' 

2.  The  preparation  of  the  '  sponge.' 

3.  The  preparation  of  the  '  dough.' 

One  sack  of  flour  Aveiglis  280  lb.,  and  94  to  9G  quartern  (4  lb.)  loaves  may 
be  obtained  from  it ;  in  other  words,  280  lb.  of  flour  yield  o7G  to  384  lb.  of 
bread.     The  following  remarks  apply  to  a  sack  of  flour. 

1.  The  '  ferment '  is  made  with  8  to  12  lb.  of  the  best  potatoes,  cleaned,  cut 
up,  boiled,  and  made  into  a  thin  paste  ;  the  temperature  of  the  mixture  is 
then  reduced  by  cold  water  to  about  30°  C.  (86°  F.)  To  it  2  lb.  of  flour  are 
added  and  one  quart  of  brewer's  yeast.  The  process  which  takes  place  in 
this  mixture  of  potato  starch,  flour,  and  yeast  is  that  the  yeast  decomposes  the 
proteids  of  the  flour  and  the  starch  of  the  potato,  forming  maltose,  dextrine, 
and  peptone-like  bodies.  The  process  is  continued  for  five  hours.  The  yeast 
becomes  very  active  with  the  sugar  and  proteid  food. 

2.  The  '  sponge  '  is  made  by  mixing  one-fouitli  or  one -third  of  the  total 
quantity  of  flour  into  the  '  ferment,'  the  water  present  being  about  30 
quarts.  Three  pounds  (48  oz.)  of  salt  are  then  added.  With  the  best  flours 
the  salt  is  not  necessary.  If  too  much  be  used,  fermentation  is  checked.  The 
chemical  process  going  on  in  the  sponge  stage  is  one  of  active  fermentation  ; 
in  about  five  hours  the  sponge  breaks,  owing  to  the  development  of  carbonic 
acid,  i.e.  the  fermentation  has  gone  a  step  further  than  the  first  stage ;  from 
the  maltose  and  dextrine  carbonic  acid  and  alcohol  are  formed.  The  sponge 
is  allowed  to  break  a  second  time. 

8.  The  remainder  of  the  flour  of  the  sack  (three-fourths  or  two-thirds) 

'  See  lecture, '  Chemistry  of  Bread-making,'  by  Dr.  Charles  Graham,  previously  quoted,, 
to  which  lecture  I  am  indebted  for  the  facts  stated. 


FOOD  4u9' 

with  the  remainder  of  the  water  (60  quarts  to  the  sack)  are  now  mixed  with 
the  sponge  and  the  dough  is  formed.  It  rises  in  an  hour,  and  is  placed  in  an 
oven  at  400  to  450°  F.  (204°  to  282°  C.)  for  an  hour  and  a  half.  The  tempe- 
rature of  the  dough  itself  is  not  much  over  100°  C.  The  chemical  processes  in 
the  dough  stage  are  not  very  active  ;  the  high  temperature  stops  the  fermen- 
tation. But  it  is  during  this  stage  that  the  bread  becomes  well  aerated,  and 
that  the  aroma  and  flavour  of  the  loaf  are  developed.  Both  these  are  very 
important  points,  and  are  useful  in  aiding  digestion.  The  fine  aroma  and  the 
*  nutty '  taste  of  good  bread  increase  the  appetite  for  food,  and  moreover  do  not 
lead  to  distaste  of  the  food.  The  aeration  allows  the  bread  to  be  better  heated 
in  the  internal  parts,  so  that  the  loaf  is  not  too  sodden,  and  thus  rendered 
indigestible. 

{h)  Bread  Aerated  by  Chemical  Mea^is  {non-fermented  Bread). — In  on& 
method,  sodium  bicarbonate  and  hydrochloric  acid  are  mixed  with  the  dough  ; 
the  carbonic  acid  formed  expands  in  the  oven,  and  the  bread  is  aerated. 

In  another.  Dr.  Dauglish's  system,  the  water  to  be  mixed  with  the  flour 
is  supersaturated  with  carbonic  acid  gas,  and  mixed  with  the  flour  under 
pressure.  The  carbonic  acid  expanding  with  the  heat  of  the  oven  aerates  the 
bread.   This  form  of  bread  is  Hkedby  some,  but  is  somewhat  tasteless  to  others. 

Baking  powders  consist  of  tartaric  acid  and  sodium  bica^rbonate  in  different 
proportions.  Church  gives  as  the  percentage  of  these  substances  in  two 
powders  the  following :  in  one,  12-8  per  cent,  tartaric  acid  and  11-9  per  cent, 
sodium  bicarbonate,  with  nearly  60  per  cent,  of  rice  flour,  a  httle  wheat 
and  rye  flour,  and  a  trace  of  common  salt ;  in  the  other,  27*6  per  cent,  of 
tartaric  acid,  31*6  percent,  of  sodium  bicarbonate,  with  some  potato  flour.^ 

Unfermented  bread,  i.e.  bread  aerated  with  carbonic  acid,  is  supposed  to 
have  the  advantage  of  not  containing  alcohol,  acetic  acid,  and  other  bodies,  the 
product  of  the  action  of  the  yeast.  It  certainly  does  not  contain  these  ;  but 
the  advantage  is  a  doubtful  one,  since  the  yeast  begins  the  digestion  of  some 
of  the  starch,  changing  it  into  maltose  and  dextrine,  and  also  of  some  of  the 
proteids,  since  peptone-like  bodies  ^  are  produced  by  it. 

Chemical  Composition  of  Bread. — From  what  has  been  said  about  the 
making  of  bread,  it  will  be  seen  that  bread  differs  in  composition  from  flour.  It 
is  a  preparation  of  flour,  indeed,  in  which  the  proteids  and  (to  a  greater  extent) 
the  starch  are  in  part  digested  ;  probably  albumoses  are  in  greater  abundance, 
and  maltose  and  dextrine,  than  in  the  flour.  The  crust  forms  not  less  than 
30  per  cent,  of  the  loaf.  Being  the  part  most  exposed  to  heat,  it  contains 
less  water  than  the  crumb  and  more  dextrine,  owing  to  the  action  of  the  heat 
into  transforming  the  starch  into  dextrine.  According  to  Van  Bibra,  the 
proteids  in  the  crust  of  bread  form  about  9"22  per  cent.,  in  the  crumb  9-86 
per  cent,  (see  Table,  p.  460) .  Even  the  best  bread  is  shghtly  acid.  Parkes  gives 
the  acidity  of  two  samples  of  good  fresh  bread  as  0-054  and  0*055  per  cent, 
respectively,  reckoned  as  glacial  acetic  acid.  The  acidity  of  good  bread  may  be 
somewhat  higher,  but  when  the  acidity  reaches  0*18  per  cent,  the  bread 
ought  to  be  condemned  as  sour.^ 

Advantages  of  Bread  as  a  Food. — These  advantages  are  easily  summed 
up.  The  development  of  an  aroma  and  of  a  pleasant  taste  during  ihe  making 
of  yeast  bread  is  a  great  aid  to  its  consumption.  In  addition  to  this  the 
bread  is  finely  divided  by  the  aerating  process  which  it  undergoes  ;  digestion 
is  thus  aided.     Part  of  the  proteids  and  starch  is  also  digested,  so  that,  as 

'  Food,  by  A.  H.  Church,  M.A.,  p.  76. 

2  These  are  probably  albumoses,  although  the  exact  nature  of  these  bodies  has  not  yet 
been  investigated. 

»  Hygiene,  pp.  717,  718. 


4G0 


HYGIENE 


lias  been  already  pointed  out  several  times,  yeast  bread  may  be  considered  as  a 
partially  digested  flour,  and  from  this  point  of  Yievf  it  must  be  regarded  as 
superior  in  a  dietary  to  the  non-fermented  forms  of  bread.  This  is  a  point 
often  lost  sight  of  in  considering  the  difterent  forms  of  bread.  It  is  true 
that  cooked  starch  is  very  readily  digested  by  the  healthy  organism,  but  a 
partial  pre-digestion  must  be  considered  an  aid  to  the  economy,  especially 
when  the  complicated  feeding  of  modern  life  is  taken  into  account. 


Table  showing  Percentage  Composition  of  Bread 

- 

Water 

Proteid 

Fat 

starch 

and 
dextrine 

Sugar 

Cellulose 

Salts 

Troportion  of 
nit.  to  non-nit. 
foodstufifs  as 

Fine  white  bread 
Coarse  bread     . 

35-59 
40-45 

7-06 
6-15 

S-00 

10-40' 
7-18 

10-90 

0-46 
0-44 

1-50 

0-30 

9-28 

1-CO 

52-56 
49-04 

4-02 

2-08 

0-32 
0-62 

1-70 
0-16 

1-20 

1-09 
1-22 

1-30 

1-50 
0-85 

1-10 

1  :7-5 

1  :  8-4 

1  :  6-3 
1  :4-7 

1  :7 

quality  (Parkes)    . 
Wholemeal        bread 

(Church) 
Biscuits  (English)     . 
Navy               biscuits 

(Church) 

40-00 

43-40 
7-45 

10-20 

49 

42 
58-08 

75-00 

2 

7 
17-02 

The  disadvantages  of  tread  as  a  food  are  those  of  flour ;  it  has  too  Httle 
salt  (sodium  chloride)  and  too  httle  fat.  Salt,  as  we  have  noticed,  is  added  in 
the  making  of  bread,  beuig  present  to  the  amount  of  about  half  an  ounce  in 
each  quartern  (4  lb.)  The  deficiency  of  fat  is  made  up  by  eating  butter  and 
fat  bacon  with  bread  ;  a  custom  originating  in  experience  and  ratified  by 
science. 

Preservation  of  Bread. — After  baking,  the  bread  begins  to  lose  water  by 
evaporation.  In  quartern  loaves  (with  crust  on  two  sides)  there  is  less  than 
6  per  cent,  loss  in  24  hours  ;  the  loss  is  greater  if  there  is  less  crust.  Stale 
bread  is  rendered  palatable  by  moistening  and  placing  in  the  oven. 

For  transport  the  bread  is  partially  dried,  the  water  being  reduced  to  12 
to  14  per  cent.  (Von  Bibra),  and  softened  with  Avater  before  using.^ 

Plain  biscuits  are  a  mixture  of  flour  and  water  well  baked.  Fancy  biscuits 
contain  butter,  eggs,  milk,  and  flavouring  agents. 

Owing  to  the  prolonged  baking,  biscuits  contain  more  dextrine  than  bread, 
and  do  not,  hke  bread,  contain  the  products  of  the  action  of  yeast  on  the  pro- 
teids  and  the  carbohydrates. 

The  composition  of  plain  biscuit  is  given  in  the  table  above.  It  differs  from 
bread  in  containing  a  much  smaller  quantity  of  water  and  a  larger  proportion 
of  organic  foodstuffs — proteids  and  carbohydrates.  Weight  for  weight,  it  is 
therefore  more  nutritious  than  bread,  and  being  easily  transported  is  useful 
as  a  substitute  for  bread  when  this  cannot  be  obtained.  It  is  apt,  however, 
to  be  tired  of. 

Macaroni  is  a  preparation  of  flour.  It  is  made  from  the  '  hard  '  wheats  of 
France  and  Italy.  The  large  quantity  of  gluten  present  in  these  hard  wheats 
allows  the  manufacture  of  the  macaroni  as  found  in  commerce. 

In  composition  it  contains  13-07  per  cent,  of  water,  9'02  of  proteids, 
0-30  of  fat,  76-77  of  carbohydrates,  and  0-84  of  salts.  Maca.roni  varies  slightly 
in  composition.     It  is  a  valuable  food,  not  much  appreciated  in  this  country. 

Vermicelli  closely  resembles  macaroni  in  its  nutritive  properties. 

'  Composed  of  9-1  per  cent,  proteids  and  1-3  nitrogenous  non-proteid  substances  (?). 
'  For  the  French  preparations  of  bread,  see  Parkes's  Hygiene,  p.  280. 


FOOD  4G1 


Examination  of  Flour. — Adulteeations 

Examination  of  Flour. — Flour  is  white  with  a  faint  yellow  tinge,  soft  to 
the  touch,  very  slightly  coherent,  and  not  gritty.  It  possesses  a  faint  cha- 
racteristic smell ;  when  mouldy,  or  commencing  to  change,  it  smells  musty 
or  sour.  Nearly  all  flours  are  slightly  acid  to  test  paper  when  moistened  \ 
strong  acidity  indicates  that  the  starch  is  beginning  to  change,  forming  vege- 
table acids. 

The  quality  of  flour  may  thus  partly  be  judged  by  its  appearance,  but  a 
further  examination  is  necessary  in  cases  of  doubt.  The  amount  of  water  has 
to  be  estimated,  the  amount  of  gluten,  and  the  kind  of  bread  the  flour  makes. 

Amount  of  Water. — The  water  should  not  be  over  15  per  cent.  The 
usual  amount  is  about  13  per  cent.  (p.  456),  but  it  may  be  as  low  as  10  and 
as  high  as  18  per  cent.  An  excess  of  water  tends  to  decomposition  of  the 
flour. 

The  amount  of  water  is  estimated  by  taking  one  gramme  of  flour  and 
drying  in  a  weighed  dish  at  100°  C.  for  two  or  three  hours.  The  flour 
and  dish  must  be  weighed  after  coohng  and  the  weight  of  the  dish  sub- 
tracted. The  loss  of  weight  in  the  flour  multiplied  by  100  gives  the  percent- 
age of  water. 

Amount  of  Gluten. — A  weighed  quantity  of  the  flour,  say  100  grammes,  is 
taken,  thoroughly  mixed  into  a  thick  paste  with  lukewarm  water,  then  put 
into  a  muslin  bag,  and  washed  in  a  stream  of  running  water  till  all  the  starch 
is  washed  away.  The  gluten  (with  some  starch)  is  then  removed  from  the 
muslin  and  again  washed  in  water  until  it  gives  no  starch  reaction  (blue 
colour)  with  iodine.  The  gluten  is  then  spread  out  and  dried  at  100°  C. 
The  weight  ought  to  be  8  to  12  per  cent,  of  the  flour.  The  gluten  obtained 
is  not,  however,  pure  proteid  ;  it  contains  some  fat  and  sometimes  bran.  It 
is  often  sufiicient  to  weigh  the  moist  gluten  ;  if  this  weight  be  divided  by  2*9 
it  gives  the  weight  of  the  dried  gluten. ^ 

The  gluten  may  be  separated  from  the  flour  in  a  dish,  without  using  the 
muslin,  but  the  muslin  hastens  the  process. 

The  amount  of  gluten  is  a  test  of  the  bread-making  quahty  of  the  flour. 
There  are,  however,  other  ways  of  testing  this.  The  gluten  is  in  one  method 
separated  from  the  flour,  put  into  atube  and  then  into  the  baking  oven.  Accord- 
ing to  the  amount  of  expansion  of  the  gluten,  so  is  the  bread-making  quality 
of  the  flour  judged.^  Another  method  suggested  by  Dr.  Charles  Graham  is 
the  following  : — To  one  ounce  of  flour  four  ounces  of  water  are  added,  and  the 
mixture  allowed  to  stand  at  the  temperature  of  26°'5  to  29°"5  C.  for  two  hours. 
It  is  then  filtered,  and  one  ounce  of  the  last  clear  portions  of  filtrate  is 
mixed  with  one  ounce  of  methylated  spirit.  A  precipitate  occurs,  consisting 
of  maltose,  dextrine,  and  soluble  proteids,  and  the  amount  of  this  precipitate 
is  a  sign  of  the  amount  of  soluble  matter  produced  during  the  sponge  stage 
of  bread  making.  This  method  is  really  an  indirect  way  of  estimating  the 
amount  of  gluten  in  the  flour.^ 

These  methods  are  well  supplemented,  or  even  replaced,  by  making  a  test 
loaf  of  bread  from  the  flour  which  is  being  investigated.  This  bread  can 
then  be  examined  by  the  methods  soon  to  be  discussed. 

For  examination  of  the  ash  see  p.  462. 

'  Parkes,  op.  cit.  p.  716. 

2  This  process  is  used  by  a  French  baker,  and  is  quoted  by  Dr.  C.  Graham  in  hia 
lecture. 

'  Graham,  op.  cit.  p.  18. 


462 


HYGIENE 


I 1 ! ) j r-^ i 1 , : 1 

Pig.  107. — Puccinia  :  hyphse  and  spores  (Parkes). 


Parasites  and  Adulterations  of  Flour 

Parasites,  both  vegetable  and  animal,  occur  in  flour  and  are  to  be  detected 
by  microscopical  examination. 

The  commonest  vegetable  parasite  is  a  fungus,  Puccinia,  of  two  or  more 
species.  These  are  recognised  by  the  tubules  or  hyphffi,  on  which  are  placed 
the  spherical  sporangia,  containing  numerous  spores.  One  species  of  Puc- 
cinia causes  the  svmt  or  caries  : 
it  makes  the  bread  bluish  in 
colour  and  may  produce  diar- 
rhoea. 

Bacteria  are  also  found  in 
decomposing  flour. 

A  mite  (Acarus  farina)  is 
also  found  in  flour  which  is 
beginning  to  decompose.  It 
has  a  rounded  body  with  six  or 
eight  legs,  and  a  pointed  head 
supported  by  protruding  man- 
dibles. The  eggs  are  oval. 
The  weevil  [Calandra  gran- 
aria)  is  much  larger  than  the  flour  mite,  and  is  readily  recognised  with  the 
naked  eye  :  it  is  about  five  millimetres  long  and  the  body  is  narrow,  and  has 
three  pairs  of  legs  attached.^ 

The  adulterations  of  flour  fall  into  two  classes,  the  mineral  and  the  organic. 
The  mineral  are  sand,  clay,  plaster  of  Paris,  magnesium  or  calcium  car- 
bonate, and  alum. 

For  the  ready  detection  of  large  quantities  of  mineral  substances,  the 
following  method  is  useful :  5  grammes  of  flour  are  shaken  with  30  to  40 
cubic  centimetres  of  chloroform,  the  mineral  substances  sink  to  the  bottom 
of  the  tube,  while  the  lighter  starch  and  proteids  float.  An  examination  of 
the  ash  is,  however,  necessary.  When  incinerated  to  white  ash,  the  residue 
ought  not  to  be  more  than  2  per  cent,  of  the  flour.  If  the  ash  is  more  than 
this,  effervescence  with  acid  (hydric  chloride)  shows  added  carbonates  of  the 
heavy  metals,  which  must  be  tested  for.  A  large  amount  of  sulphates  in  the 
ash  means  plaster  of  Paris  (calcium  sulphate).  Clay  is  shown  by  its  insolu- 
bility m  acids  and  in  water.  Lead  is  readily  detected  by  heating  in  the 
blowpipe,  when  a  bead  is  formed,  or  by  dissolving  the  ash  in  acid  and  testing 
for  the  metal. 

The  organic  adulterations  are  the  starch-containing  flours  from  the  other 
cereals,  from  LeguminosaB,  and  from  a  few  other  plants.  Flour  is  thus  found 
mixed  Avith — 

Barley  Buckwheat 

Maize  Millet 

Oats  Melampyrum 

Rye  Lohum 

Potato  Agrostemma  (corncockle)  j- rare  admixtures. 

Peas  and  beans  Rhinanthus 

Eice  Ergot 

The  addition  of  barley,  oats,  rye,  maize,  and  the  other  cereals  to  wheaten 
flour  does  not  make  it  harmful ;  but  it  lowers  the  value  of  the  bread  made 

'  For  an  account  of  the  moth  {Ephcstia  clutclla)  -which  is  sometimes  found  in  flour 
see  Parkes's  Hygiene,  p.  277. 


FOOD  4(J3 

from  it.  The  addition  of  buckwheat,  Melampyrum,  of  Agrostemma,  of  Rhin- 
anthus,  and  of  ergot,  causes  the  bread  made  from  such  flours  to  be  coloured, 
while  the  bread  containing  Lolium  and  ergot  is  poisonous,  Lolium  does  not 
colour  the  bread. 

The  detection  of  the  additions  to  flour  rests  almost  solely  on  the  cha- 
racters of  the  starch  grain  peculiar  to  each  plant.  For  these  characters  (see 
pp.  451-454).  But  there  are  other  facts  which  aid,  viz.  the  structure  of  the 
envelopes  of  the  grains,  which  differ  in  each  plant,  and  part  of  which  is  always 
present  even  in  the  best  milled  grains. 

The  addition  of  potato,  of  peas  and  beans,  of  oats,  of  maize,  and  of 
rice,  is  readily  detected  by  the  characters  of  the  starch  grains  alone.  With 
peas  and  beans,  too,  a  large  amount  of  cellulose  is  present,  which  is  detected 
under  the  microscope  after  adding  liquor  potassae  to  dissolve  the  starch. 
The  detection  of  barley  is,  however,  much  more  difficult.  The  starch  grains 
closely  resemble  those  of  wheat  in  size  and  shape.  The  envelopes  of  the 
barley  grain  also  closely  resemble  those  of  Vt^heat,  but  they  are  distinguished 
by  their  greater  delicacy  in  structure. 

Rye  starch  grains  resemble  those  of  wheat,  but  the  rayed  hilum  distin- 
guishes them.  The  rayed  hilum  is  also  seen,  it  must  be  remembered,  in  the 
starch  grains  of  old  wheat,  but  they  are  not  nearly  so  numerous  as  in  rye  flour. 

Buckwheat  is  detected  by  the  small  round  starch  grains  and  by  the  struc- 
ture of  the  coatings,  and  especially  the  large  cellulose  spaces  containing  the 
starch  grains.  It  is  an  adulteration  of  wheat  from  the  Baltic.  Millet  is 
found  as  an  adulteration  of  wheats  from  Asia  and  Africa. 

Flour  adulterated  with  Melampyrum  is  not  altered  in  colour,  but  the  bread 
made  with  it  has  a  smoky- violet  tint, 

Agrostemma  (corncockle)  gives  bread  a  greenish  colour,  while  Rhinanthus 
imparts  a  bluish-black  colour  to  the  bread.  The  admixture  of  MelampyruQi, 
Agrostemma,  or  Rhinanthus  does  not  cause  poisonous  symptoms, 

Lolium  temulentum  (darnel),  however,  makes  the  bread  poisonous. 
The  symptoms  produced  are  to  some  extent  gastro-intestinal,  but  are  chiefly 
referable  to  the  nervous  system.  Thus  there  is  a  sensation  of  heat  in  the 
throat,  vomiting,  headache,  giddiness,  staggering,  tremulous  gait,  impaired 
vision,  and  symptoms  of  collapse.  Convulsions,  hallucinations,  dehrium,  and 
paralysis  may  also  be  observed, 

Lolium  may  be  detected  by  the  following  tests.  An  alcoholic  extract  is  of 
a  greenish  colour  and  disagreeable  taste.  The  alcohoHc  extract  of  wheaten 
flour  is  yellowish,  and  has  not  a  disagreeable  taste. 

Vogel  says  that  the  following  reaction  is  given  with  flour  adulterated  with 
Agrostemma,  Lolium,  beans,  or  ergot.  If  to  two  grammes  of  the  flour  10  cubic 
centimetres  of  70  per  cent,  alcohol  are  added,  and  then  5  per  cent,  hydric 
chloride,  an  orange  yellow  colour  is  obtained.'  Ergot  of  rye  is  occasionally 
mixed  with  wheaten  flour,  but  not  in  this  country.  It  is  of  most  importance 
in  connection  with  rye  bread,  which  is  so  commonly  used  on  the  Continent 
(see  p.  466). 

Examination  of  Bread 

The  crust  of  bread  should  be  yellowish  brown,  firm,  and  not  aerated. 
The  crumb  of  bread  is  porous  and  elastic.     There  should  be  no  sour  smell. 

Potato-flour  makes  bread  soft,  while  barley  flour  makes  it  dry. 

-iwo-zm^  o/ wafer  is  important  to  estimate.  It  varies  from  30  to  40  per 
cent.     In  bad  bread  it  is  50  per  cent. 

'  On  this  and  other  points  in  detail,  see  A.  E.  Vogel,  Naliru'ngs-  und  Genuss-Mittcl 
aus  dem  Pflanzenreiche,  Vienna,  1872  ;  Die  Vntenucliungcn  des  Mehles,  1880. 


464  HYGIENE 

The  acidify  of  bread  has  ah-eady  been  discussed  (p.  459). 
The  ash  of  bread  ought  never  to  be  over  3  per  cent.    Potatoes  render  the 
ash  alkaline,  due  to  sodium  carbonate. 

Alum  is  added  to  bread  to  improve  the  colour  and  to  stop  fermentation. 
Ordinaiy  bread  may  contain  a  small  quantity— about  0005  per  cent. — of  phos- 
phate of  aluminium  (AVanklyn).  This  amount  must,  therefore,  be  deducted 
from  the  alum  found  in  the  bread  examined,  the  result  giving  the  amount  of 
the  salt  added.  The  alum  present  in  alumed  bread  varies— 12  grains  m  a 
quartern  loaf,  or  even  41-6  grains. 

Copper  sulphate  is  readily  detected  by  testing  a  watery  extract  of  bread 
-with  potassium  ferrocyanide  :  a  brown  colouration  or  precipitate  is  the 
result. 

The  microscopical  examination  of  bread  is  important.  It  may  show 
fungi,  with  their  mycelium  and  spores  (Penicillium) ,  or  bacteria  in  decom- 
posing bread. 

The  deleterious  ei'fects  of  bad  bread  are  due  partly  to  its  indigestibility 
and  partly  to  the  poisons  contained  in  it. 

Bread  containing  too  much  water,  sodden  bread,  is  indigestible,  causing 
a  sense  of  weight  in  the  stomach,  &c.  Acid  bread  also  disagrees.  Acidity 
is  due  chiefly  to  the  fatty  acids,  and  these  cause  acidity  and  increase  this 
symptom  if  already  present.  Acid  bread  may  also  lead  to  diarrhoea.  The 
symptoms  produced  by  decomposing  bread  are  those  of  decomposing  food 
generally,  referable  to  the  gastro-intestinal  tract.  The  presence  of  fungi 
(not  bacteria)  is  also  said  to  lead  to  diarrhoea  ;  their  presence  shows  that  the 
bread  is  beginning  to  decompose,  and  it  is  not  known  whether  they  are  of 
themselves  harmful  or  whether  the  bacteria  present  in  such  bread  are  the 
real  poisonous  agents.^ 

Alumed  bread  causes  dyspeptic  symptoms,  with  constipation,  probably 
only  when  there  is  a  large  amount  of  alum  present  in  the  bread.  Alum  is 
added  to  inferior  flours,  and  it  is  a  question  how  far  these  flours  themselves 
are  really  responsible  for  the  symptoms.  There  is  no  doubt  that  alum  does 
constipate,  and  not  only  that  it  is  itself  no  food,  but  that  it  combines  with 
some  of  the  phosphates  of  the  bread  forming  insoluble  aluminium  phosphate. 
Its  use  is  therefore  rightly  declared  illegal. 

It  is  not  known  whether  the  small  amount  of  sttlphate  of  copper  some- 
times present  in  bread  causes  harmful  symptoms. 

Lead  p)oisoning  is,  however,  rarely  a  consequence  of  the  eating  of  bread. 
It  has  occurred  where  the  holes  in  the  millstones  have  been  repaired  with 
the  molten  metal,  and  where  old  wood  which  had  been  painted  has  been  used 
for  heating  the  baking  oven.'^ 

The  symptoms  produced  by  bread  containing  Lolium  temulentum  have 
already  been  described.     For  those  caused  by  ergotised  bread  see  p.  4G7. 

Baeley  [Hordeum  vulgare) 

The  barley  of  commerce  exists  in  two  forms — the  pot  barley,  which  is 
simply  the  husked  grain ,  and  the  pearl  barley,  which  is  the  cleaned  grain, 
somewhat  polished  by  the  process  of  cleaning.  Its  grain  is  also  ground 
into  flour,  and  is  called  prepared  barley.     It  is  liable  to  adulteration. 

As  a  Food. — Barley  is  very  nutritious.  In  percentage  composition  it 
closely  resembles  wheaten  grain.     There  is,  however,  a  great  difierence  in  the 

'  Aspergillus  glaucus  seems  to  poison  horses,  causing  paralysis.  See  Parkes,  op.  cit. 
p.  291. 

==  See  Alforcl,  Sanitary  Eccord,  1877. 


FOOD  4G5 

character  of  the  proteids  present.  These  do  not,  hke  those  of  wheaten  flour, 
form  gluten  on  the  addition  of  water ;  they  exist  solely  in  the  form  of  what  some 
agricultural  chemists  call '  soluble  albuminoids.'  According  to  Eitthausen,  they 
consist  of  gluten-casein,  gluten-fibrin,  mucedin,  and  albumen.^  According  to 
my  own  researches,  they  consist  of  globulin,  albumose,  and  albumen.  Eitt- 
hausen alone  is  responsible  for  the  body  named  mucedin,  which  is  supposed 
to  be  vegetable  mucin. 

This  chemical  difference  between  the  proteids  of  wheat  and  barley  very 
probably  also  means  a  nutritive  difference ;  but  it  is  almost  impossible  to 
speak  definitely  on  this  point.  It  is,  however,  evident  that  the  great  advan- 
tage of  wheaten  flour  as  a  food  is  that  it  can  be  made  into  bread,  which,  as 
we  have  previously  insisted  upon,  is  not  only  a  very  palatable,  but  a  digestible 
and  a  partially  digested  food. 

A  weak  solution  of  barley  starch  is  added  to  milk  in  infant  feeding  to 
diminish  the  size  of  the  curds  found  in.  the  stomach.  As  far  as  is  known,  the 
disadvantages  of  barley  as  a  food  rest  almost  solely  in  its  insipidness  ;  it  is, 
like  other  vegetable  food,  liable  to  cause  digestive  disturbance  if  too  freely 
partaken  of. 

Oats  {Avena  sativa) 

Oatmeal  is  a  valuable  food,  as  is  evidenced  by  its  extensive  use  among 
the  Scotch  peasantry,  with  whom,  indeed,  it  was  at  one  time  the  chief 
food. 

The  advantage  of  oatmeal  as  a  food  depends  on  the  fact  that  it  can  be 
taken  for  long  periods  without  distaste,  and  that  the  proteid  constituents  are 
in  large  amount,  the  carbohydrate  in  fair  proportion  (less,  however,  than  in 
wheat  or  barley),  while  there  is  a  relatively  large  amount  of  fat  present. 
This  last  foodstuff  distinguishes  oatmeal  greatly  from  wheaten  flour  or  barley. 
The  proteids  present  are  called  gliadin  and  gluten-casein  (avenin).  They 
differ,  like  those  barley,  from  the  proteids  of  wheat  in  not  forming  gluten  on 
the  addition  of  water.  On  referring  to  the  analysis  of  oatmeal  on  p.  456,  it 
will  be  seen  that  the  proportion  of  the  proteids  to  the  non-nitrogenous  organic 
foodstuffs  in  it  (1  :  5*4)  more  nearly  approaches  the  normal  relation  in  a  dietary 
(1  :  3^  or  4)  than  that  in  barley  or  wheat.  It  is  therefore  more  suitable 
to  constitute  a  large  part  of  the  dietary  than  either  of  these  cereals,  if  it  were 
not  for  certain  drawbacks  to  its  use.  One  of  these  is  that  oatmeal  contains 
a  large  quantity  of  cellulose,  which  is  apt  to  irritate  the  intestines,  and  at  any 
rate  interfere  with  the  complete  digestion  and  absorption  of  the  foodstuffs. 
The  coarse  oatmeals  contain  more  cellulose  than  the  fine  preparations,  and 
are  thus  more  liable  to  cause  intestinal  irritation.  Oatmeal  requires  salt. 
The  pericarp  of  oats  contains  an  alkaloidal  principle,  which  is  a  stimulant  to 
the  muscles  ;  it  causes  excitement  in  horses.^  This  alkaloid  may  perhaps 
account  for  some  of  the  beneficial  effects  of  the  use  of  oatmeal  in  those  who 
do  hard  manual  labour,  as  well  as  in  the  hardy  fighters  of  the  Highlands. 

Oatmeal  is  adulterated  with  barley,  the  admixture  being  readily  detected 
by  attention  to  the  size  and  shape  of  the  starch  grains  (see  p.  454).  Eice 
and  maize  may  also  be  found  in  the  meal ;  the  starch  grains  are  characteristic 
in  both.     The  husks  of  wheat  and  barley  may  also  be  added. 

*  For  Eitthausen' s  laborious  researches  on  the  composition  of  cereals,  &c.,  see  his  Die 
Eiiveisskorper  der  Getreidearten,  &c.,  1872.  Since  Kitthausen's  work  the  nomenclature 
of  the  proteids  has  altered,  and  the  researches  of  recent  years  render  a  re -examination  of 
the  proteids  of  plants  necessary. 

^  See  Brunton's  Pharmacology,  3rd  ed.  p.  1056. 

VOL.    I.  H  H 


466 


HYGIENE 


EiCE  {Orijza  satlva) 

The  grains  are  busked,  the  cuticle  removed  by  machiner)',  the  dust  brushed 
off,  and  the  surface  of  the  grain  poHshed  to  a  greater  or  less  extent.  Many 
varieties  exist  in  commerce,  the  better  class  of  which,  Java,  Japan,  Carolina, 
Patna,  are  well  polished,  while  the  inferior  varieties,  Eangoon,  &c.,  are  not 
so  well  cleaned.  These  inferior  varieties  vary  in  colour,  being  reddish  some- 
times, contrasting  greatly  with  the  yellowish-white  colour  of  the  better 
varieties.  Eice,  therefore,  ought  to  be  well  cleaned,  with  a  certain  polish  on 
the  surface,  free  from  dust  and  with  the  grains  whole  and  not  broken.  Un- 
cleaned  or  partially  cleaned  rice  is  in  use  among  the  peasantry  in  India  and 
Burmah. 

As  a  food,  rice  must  be  considered  almost  solely  as  a  starchy  food.  The 
percentage  of  proteids  is  small  (p.  45G),  while  that  of  the  carbohydrates  is 
very  large — over  78  per  cent.  The  salts  are  also  greatly  deficient.  When 
rice  is  taken,  therefore,  salt  has  to  be  added  to  supply  the  deficiency  of 
mineral  foodstufis,  meat  or  peas  and  beans  to  supply  the  deficiency  of  pro- 
teid,  and  animal  fat  (butter,  &c.)  to  supply  the  fat  necessary.  Taken  in  such 
a  mixture,  rice  is  a  valuable  food ;  when  taken  alone,  it  has  to  be  consumed 
in  too  large  quantities  to  supply  the  amount  of  proteid  necessary  for  the 
body. 

The  cooking  of  rice  is  important ;  it  should  never  be  boiled,  but  steamed  so 
that  none  of  the  proteid  is  lost. 


Eye  [Secale  cereale) 

Eye  is  a  more  important  food  in  the  northern  countries  of  Europe  than 
in  our  own  country.  It  is  extensively  grown  abroad,  where  it  is  made  into 
bread — Schwarzbrod,  Pumpernickel,  &c. — and  is  the  bread  of  the  poorer  classes. 
In  this  country  rye  grain  is  chiefly  used  for  malting.  Eye  is  a  very  nutri- 
tious grain  :  in  percentage  composition  it  closely  resembles  wheat  (see  p.  456). 
The  proteids  present  ^  form  a  kind  of  gluten  on  the  addition  of  water,  but 
not  to  so  great  an  extent  as  in  wheat,  nor  can  the  gluten  be  so  readily 
separated. 

The  bread  made  from  rye  is  dark  in  colour,  heavy,  and  very  acid;  it  retains 
its  moisture  a  long  time. 


Percentage  Composition  oj 

"  Bye  Bread 

- 

Water 

Proteid 

Fat 

Sugar 

starch 

Cellulose 

Salts 

German  rye-bread 
Pumpernickel-      .... 

42-27 
43-42 

6-11 

7-59 

0-43 
1-51 

2-31 
3-25 

46-94 
41-87 

0-49 
0-94 

1-46 
1-42 

The  percentage  composition  does  not,  therefore,  differ  greatly  from  that  of 
wheaten  bread  (see  p.  4G0).  The  great  drawbacks  to  rye  bread  are,  however, 
that  it  is  heavy  and  acid,  and  thus  indigestible  and  liable  to  cause  diarrhoea. 
It  has  a  peculiar  odoiu'  and  taste,  and  one  not  pleasant  to  those  accustomed 
to  wheaten  bread.  A  better  bread  is  made  by  mixing  wheaten  flour  with  rye 
in  the  proportion  of  two  to  one. 

'  These  proteids,  according  to  my  analysis,  are  globulin  and  albumose — the  same, 
therefore,  that  occur  in  wheaten  flour.  Eitthausen  calls  them  vegetable  fibrin,  casein, 
and  albumen  {op.  cit.) 

2  The  blackbread  of  Northern  Germany,  made  from  the  whole  of  the  rye  grain. 


FOOD  467 

As  regards  the  digestibility  of  rye  bread  compared  with  white  brea,d,  G. 
Meyer '  has  shown  that  with  white  bread  a  large  proportion  of  the  proteids 
and  salts  is  absorbed  than  with  Pumpernickel  or  with  Munich  rye  bread, 
and  that  this  latter  form  of  rye  bread  is  more  digestible  than  the  North 
German  commodity.  There  can  be  no  question,  therefore,  of  the  superiority 
of  wheaten  bread. 

Eye  grain  is  subject  to  a  disease  caused  by  a  fungus,  the  Claviceps  pur- 
purea.  The  growth  of  this  fungus  causes  the  grain  to  enlarge  and  become 
black,  producing  what  is  known  as  ergot  of  rye.  The  ergot  gets  mixed  with 
the  healthy  rye  grain,  and  its  presence  in  the  bread  leads  to  a  varying  train 
of  symptoms  called  ergotism.  This  disease,  which  is  practically  unknown  in 
this  country,  is  more  common  in  those  countries  where  rye  bread  is  a  staple 
food,  but  it  is  getting  less  common  now  owing  to  the  greater  care  in  the 
selection  and  the  milling  of  the  grain. 

Ergotism  occurs  in  epidemics,  and  is  partly  due  to  the  ergot  and  partly 
to  the  deterioration  (weight  for  weight)  of  the  food  by  the  presence  of  the 
fungus.  The  symptoms  begin  with  loss  of  appetite,  vomiting,  and  diarrhoea, 
and  then  assume  one  or  two  forms.  In  one  form,  gangrene  of  an  extremity 
is  the  chief  symptom  ;  this  is  no  doubt  rightly  ascribed  to  the  contraction  of 
the  arterioles,  caused  by  ergot  cutting  off  the  blood  supply  to  the  part.  In 
the  other  form  the  symptoms  are  referable  to  the  nervous  system.  There  is 
giddiness  with  loss  of  sensation  in  the  extremities  and  abnormal  sensations 
in  the  skin.  There  may  also  be  convulsions,  and  definite  alterations  of  the 
posterolateral  columns  of  the  spinal  cord  have  been  found. 

Ergot  may  be  detected  in  the  flour  by  the  microscope  by  which  the 
mycelium  and  spores  of  the  fungus  will  be  seen.  The  following  chemical 
tests  have  been  suggested.  To  10  grammes  of  flour,  15  grammes  of  ether  are 
added  and  20  drops  of  dilute  sulphuric  acid  (1  in  5) ;  the  mixture  is  shaken, 
and  on  adding  5  drops  of  a  saturated  solution  of  sodium  bicarbonate  a 
violet  colour  is  developed  (Hoffman  and  Wolff).  By  another  method  a  paste  of 
the  flour  is  made  with  an  alkali,  and  dilute  nitric  acid  added  to  excess  ;  the 
2nixture  when  neutralised  gives  a  violet  red  colour  (Laneau). 

Maize  (Zea  mats,  Indian  Corn,  and  Corn) 

This  is  an  important  food  in  some  countries — those  of  Southern  Europe 
and  of  America — but  it  is  not  much  used  in  this  country.  In  Italy  it  is 
called  polenta.  The  percentage  composition  of  the  maize  flour  (p.  456)  shows 
it  to  be  a  very  nutritious  food ;  and  indeed  in  some  parts  maize  cakes  take 
the  place  of  bread  as  the  staple  vegetable  food.  Made  into  cakes,  it  is  of 
course  not  to  be  compared  to  bread  either  for  palatableness  or  digestibility ; 
but  people  are  said  soon  to  get  accustomed  to  its  use.  It  is  best  taken  as 
porridge,  made  either  from  corn  flour,  oswego,  or  from  the  ground  whole- 
maize.  In  the  preparation  of  corn  flour,  not  only  is  the  cellulose  removed, 
but  a  large  quantity  of  the  proteids  ;  so  that,  although  more  digestible  than 
whole  maize,  it  contains  a  smaller  percentage  of  proteid  foodstuffs. 

Like  oats,  maize  contains  a  large  quantity  of  fat.  Some  of  its  proteids 
have  been  described  under  the  name  of  Ze'in,  but  what  this  body  really  is,  is 
not  at  present  known. 

The  deleterious  effects  of  maize  depend  partly  on  imperfect  cooking,  thus 
causing  indigestion,  and  partly  on  putrefactive  decomposition. 

Putrefied  maize  is  said  to  contain  at  least  two  poisonous  principles  (pro- 
bably alkaloidal  in  action).   One  of  these  produces  muscular  spasms,  the  other 

'  Quoted  by  Konig,  op.  cit.     See  also  the  original  paper  in  Zeits.  f.  Biologic.  1871,  p.  1. 

B  H  2 


468 


HYGIENE 


has  a  narcotic  action.     The  proportion  in  which  the  two  substances  rela- 
tively exist  in  the  decomposed  maize  appears  to  vary. 

A  disease  of  maize,  whether  due  to  the  fungus  Sporisorium  ma'icUs 
(Verdet)  or  the  so-called  Bacterium  maidis,  seems  to  be  one  of  the  factors  in 
the  production  of  'pellagra,  a  malady  occurring  in  Lombardy.  There  may  be 
other  factors,  such  as  impoverished  food  ;  for  not  only  do  some  of  the  symp- 
toms (such  as  serous  effusions,  &c.)  resemble  those  of  scurvy,  but  the  main 
treatment  of  the  disease  is  one  of  a  generous  diet  of  fresh  animal  and  vegetable 
food..  Among  the  many  symptoms  of  pellagra,  the  erythematous  affection  of 
the  skin,  fj.'om  which  the  disease  derives  its  name,  seems  to  be  the  least  im- 
portant. There  are  gastro-intestinal  symptoms,  such  as  nausea,  diarrhoea, 
heat  of  epigastrum,  and  a  voracious  appetite,  but  the  chief  s}Tnptoms  are 
nervous.  The  subjects  of  pellagra  suffer  chiefly  from  melancholia,  with  stupor 
and  suicidal  tendencies,  arising  in  some  cases  from  the  intolerable  burning- 
sensation  of  the  skin.  Fainting  is  common,  muscular  spasms  and  contracture 
are  also  noticed ;  some  cases,  indeed,  closely  resemble  spastic  paralysis,, 
showing  an  affection  of  the  lateral  columns  of  the  spinal  cord.  The  nervous 
affections  in  pellagra  are  therefore  as  important  as  those  observed  in  cases  of 
ergotism.^ 

Millet  and  Buckwheat 

Millet  is  a  food  largely  used  in  hot  countries,  Italy  and  the  Iberian  Penin- 
sula in  Europe,  in  Africa,  and  in  parts  of  Asia  (India,  China,  &c.)  It  is 
obtained  from  different  plants  :  thus  the  common  millet  is  prepared  from 
Panicum  miliaceum ;  the  Indian  or  small  millet  (Guinea-  corn,  Dharra)  from 
Sorghum  vulgar e ;  Italian  millet  is  from  Setaria  italica  ;  ^  German  millet 
from  Setaria  gcrinanica ;  spiked  millet  fi'om  Pencillaria  sjncata  ;  and  golden- 
coloured  millet  from  Sorghum  saccharatum. 

The  chemical  composition  of  the  seeds  of  these  different  grasses  is  very 
similar.  The  salts  consist,  like  other  cereals,  largely  of  phosphates,  but  also 
contain  silica. 


Percentage  Composition  of  Millet  and  Biickivheat  {shelled) 


- 

Water 

Proteid 

Pat 

Carbo- 
hydrate 

Cellulose 

Salts 

Proportion  of 
nit.  to  non-nit. 
foodstuffs  as 

Pa7iimiminiliacewn  {comm.on 

millet)         .... 

11-79 

10-51 

4-26 

68-16 

2-48 

2-80 

•  1  :  6-89 

Sorghum  vzilgare  (small  mil- 

let)       

11-46 

8-96 

3-79 

70-25 

3-59 

1-95 

1  :  8-20 

Setaria  italica  (Italian  millet) 

12-04 

7-40 

3-87 

74-21 

1-37 

1-11  ■' 

1 :  lo-sa 

Sorgluim  saccharatum  (golden- 

coloured  millet)  . 

15-17 

9-26 

3-36 

67-99 

2-51 

1-71 

1  :  7-70 

Polygonum  faqopynim  (buck- 

wheat)        .... 

12-68 

10-18 

1-90 

71-73 

1-65 

1-80 

1  :  7-10 

From  this  composition,  millets  are  evidently  a  nutritious  food  ;  millet 
bread  can  be  made,  and  is  a  substitute  for  wheaten  bread. 

Buckwheat  (nat.  ord.  Polygonacete)  is  less  nutritious  as  a  food  than  its 
composition  would  indicate  ;  this  is  eminently  the  case  if  the  seed  is  not 
shelled,  as  the  coating  contains  a  large  amount  of  cellulose.  If  the  whole 
seed  be  crushed,  and  used,  cellulose  is  found  to  be  present  to  the  extent  of 

'  See  Tuczek,  Deutsche  med.  Wochcnschr.  1888,  No.  12,  for  the  nervous  symptoms,  and 
Neusser,  Wien.  med.  Wochenschr.  1887,  No.  5. 
^  Panicum  italicum. 
^  From  the  analysis  of  0.  Kellner,  quoted  by  Konig,  op.  cit. 


FOOD  409 

14*32   per  cent,,  while  in  the  shelled  seed  it  forms  1-G5  per  cent,  of  the 
food. 

Baggy  is  obtained  from  Eleusine  corocana.  It  is  used  largely  in  some 
parts  of  India,  and  is  said  to  be  very  nutritious. 

Chestnuts  [Gastanea  vesca) 

Belonging  to  the  same  class  of  foods  that  have  just  been  considered  is 
the  edible  chestnut.  The  amount  of  proteids  and  carbohydrates  present 
closely  resembles  that  present  in  the  cereals.  Thus  there  are  10-76  per  cent, 
of  proteids,  2*90  per  cent,  of  fat,  73*04  per  cent,  of  carbohydrate  (almost  solely 
starch),  2'99  of  cellulose,  2*97  of  salts,  and  7'34  of  water  in  the  shelled  seed. 
Chestnuts  are  therefore  chiefly  a  carbohydrate  food  ;  to  a  secondary  extent, 
also  a  proteid  food.  In  some  parts  of  the  Continent  (Germany  and  Spain) 
they  form  a  staple  food  of  the  population,  replacing  bread. 

CLASS  II 

The  second  class,  into  which  we  have  divided  vegetable  foods,  include 
those  which  contain  a  large  percentage  of  proteid  and  of  carbohydrate  ;  so 
that  they  are  both  proteid  and  carbohydrate  foods.  To  this  class  belong  the 
seeds  of  the  Leguminosse,  which  are  used  as  food,  and  a  Peruvian  food — 
white  quinoa,  obtained  from  the  Ghcnopodium  guinoa.  As  a  subdivision  of 
this  class  will  be  considered  certain  vegetable  products,  which,  besides  con- 
taining a  large  amount  of  proteid,  contain  a  large  amount  of  fat  with  a  vary- 
ing amount  of  carbohydrate.  These  vegetable  foods  may  be  described  as  oily 
seeds ;  such  as  linseed,  the  walnut,  the  ground-nut,  &c.  They  are  not  of 
much  importance  in  this  or  other  civilised  countries  as  food,  but  it  is  well  to 
bear  in  mind  their  nutritive  importance  in  times  of  scarcity  of  the  staple 
foods. 

1,  With  regard  to  the  seed  of  the  Lcgtiminosce,  it  must  be  remembered 
fthat  they  are  used  as  food  in  two  states,  fresh  and  dried,  and  that  the  per- 
centage chemical  composition  differs  in  the  two  conditions  owing  to  the 
large  amount  of  water  present  in  the  fresh  seeds. 

All  these  seeds,  too,  possess  an  aroma  which  is  intensified  during  cooking ; 
the  older  and  drier  the  seed  the  greater  the  aroma  up  to  a  certain  point. 

The  character  of  the  proteids  present  have  not  been  much  investigated. 
These  bodies  are  described  as  legumin  and  conglutin  (see  p.  450),  and  are 
■sometimes  called  vegetable  caseins.  But  it  is  probable  (see  Vines,  already 
•quoted)  that  the  greater  part  of  the  legumin  and  conglutin  is  derived  during 
■extraction  from  the  globulin  and  albumose  present  in  the  seed. 

There  is  a  large  amount  of  cellulose  present  in  the  dried  seeds,  a  circum- 
stance which  leads  to  diminished  digestion  and  absorption.  In  the  salts 
present,  the  phosphates  and  potassium  and  calcium  predominate,  as  in  other 
vegetable  foods,  over  the  chlorides  and  sodium.  Most  of  these  seeds,  as  other 
vegetable  foods,  contain  a  small  percentage  of  iron,  combined  probably  with 
an  organic  body.  White  quinoa  is  particularly  rich  in  iron  (see  p.  455).  The 
■digestibility  of  the  seeds  of  leguminous  plants  is  an  important  point.  M. 
Eubner  in  a  series  of  experiments  found  that  from  about  21  to  30  per  cent,  of 
the  nitrogen  of  peas  was  passed  out  undigested  in  the  faeces,  as  compared  with 
13  to  14  per  cent,  of  the  nitrogen  of  white  bread,  and  about  17  per  cent,  of 
blackbread.  Eutgers'  experiments  showing  the  unsuitability  of  leguminous 
seeds,  as  replacing  animal  proteids,  have  already  been  described.  The  mode 
■of  preparation  of  the  dried  leguminous  seeds  is  all-important  from  a  diges- 


470 


HYGIENE 


tive  point  of  view.  Striimpell,'  for  example,  found  that  when  ground  into 
meal  and  mixed  with  milk,  butter,  and  eggs  as  in  the  ordinary  mode  of 
cooking,  the  seeds  of  Leguminosae  were  more  completely  digested  than  when 
cooked  whole  and  by  themselves.  This,  of  course,  means,  that  in  the  first 
case  the  food  was  more  finely  divided  and  the  digestible  foodstuffs  removed 
more  completely  from  their  indigestible  (cellulose)  covering.  These  remarks 
do  not  apply  to  the  fresh  seeds — such  as  peas — which  are  rendered  quite  soft 
and  succulent  by  cooking. 

The  disadvantages  of  these  seeds  as  food  are,  that  they  are  liable  to  cause 
indigestion  if  partaken  of  in  too  large  a  quantity — leadnig  to  acidity,  flatu- 
lence, and  diarrhcea.  They  lack,  too,  fat  and  sodium  chloride  ;  these  ought  to 
be  added  in  the  cooking. 


Percentage  ComiMsition  of  Seeds  of  Legtwiinosoi,  dc. 


Proportion  of. 



Water 

Protcid 

Pat 

liydrate 

Cellulose 

Salts 

uit.  to  non-nit. 

foodstuffs  as 

1.  Peas  {Pisztin  sativuvi) : 

Green      .... 

78-44 

6-35 

0-53 

12-00 

1-87 

0-81 

1  :  2 

Dried  (average) 

13-92 

23-15 

1-89 

52-68 

5-68 

2-68 

— 

Pea  flour 

11-41 

25-20 

2-01 

57-17 

1-32 

2-89 

1  :2-3 

2.  Beans  (Vicia  faba)    . 

13-49 

25-31 

1-68 

48-33 

8-06 

3-13 

— 

Bean  flour 

10-29 

23-19 

213 

59-37 

1-67 

3-35 

1  :  2-6 

3.  Haricot  beans    (Phaseolus 

vulgaris) 

11-24 

23-66 

1-96 

55-60 

3-88 

3-66 

1  :  2-4 

Fresh  French  beans 

88-75 

2-72 

0-14 

6-60^ 

1-18 

0-61 

1  :  2-4 

4.  Lentil  beans  {ErviLin  lens) 

12-33 

25-94 

1-93 

52-84 

3-92 

3-04 

— 

Flour       .... 

10-73 

25-46 

1-83 

57-35 

2-01 

2-62 

1:2-3 

5.  Soja   beans  (yellow)  {Soja 

hispida,  var.  tumida) 

9-89 

33-41 

17-68 

29-31 

4-67 

5-10 

1  :  1-4 

6.  Yellow  lupin  seeds  -   {Lu- 

l)inus  luteiis)  . 

13-98 

38-25  = 

4-38 

25-46 

14-12 

3-81 

— 

7.  Lathyrus  sativus 

12-74 

24-08 

2-38 

51-38 

6-60 

2-82 

— 

8.  White  Quinoa^  (Cheuopo- 

dium  Quinoa) . 

16-01 

19-18 

4-81 

47-78 

7-99 

4-23 

1  :  2-7 

There  is  a  great  difference  between  the  composition  of  fresh  peas  and 
dried :  roughly,  1  part  of  dried  peas  by  weight  equals  4  parts  of  green  in 
proteid  and  carbohydrate. 

Soja  beans,  from  the  large  amount  of  fat  they  contain,  approximate  in 
composition  to  the  oily  seeds  presently  to  be  considered. 

Percentage  Composition  of  Oily  Seeds 


1 

Proportion  of 



Water    Proteid 

Cellulose 

Ash 

nit.  to  non-nit. 

foodstuffs  as 

1.  Linseed      {Limim     ^lsita- 

tissimmn) 

9-23 

22-57 

33-64 

23-23 

7-05 

4-28 

1  :2-5 

2.  Walnut  {Juglans  regia) 

7-18 

15-77 

57-43 

13-03 

4-59 

2-00 

1  :  4-4 

3.  Hazel  nut    {Corylus  avel- 

lana)        .... 

7-11 

17-41 

62-60 

7-22 

3-17 

2-49 

1  :4-0 

4.  Sweet  almond  (Amygdalus 

communis) 

6-02 

23-49 

53-02 

7-84 

6-51 

3-12 

1  :  2-6 

5.  Pea-  or  ground-nut  {Arachis 

hypogcca)  (shelled)  . 

6-95 

27-65 

45-80 

16-75 

2-25 

2-64 

1  :  2-2 

1  Centralb.f.  die.  vied.  Wissensch.  1876,  p.  47. 

2  The  composition  of  blue  and  garden  lupin  seeds  is  very  similar. 

^  Minus  2-25  per  cent,  for  nitrogenous  non-proteid  bodies,  leaving  the  proteid  36  per 
cent.  ■*  Analysed  by  Voelcker,  1857.  *  1"16  sugar. 


FOOD 


471 


The  character  of  the  oily  seeds  has  already  been  described.  They  are  not 
much  used  as  food,  and  are  usually  eaten  in  this  country  only  in  small 
quantities.  In  some  countries,  however,  peanuts  form  almost  one  of  the 
staple  foods. 

From  their  close  texture  these  seeds  are  indigestible  ;  and  they  do  not 
cook  well. 


CLASS  III 

To  this  class  belong  vegetable  foods  which  are  chiefly  used  as  yielding 
carbohydrates.  The  commercial  starches  and  sugars  (sago,  arrowroot,  &c.) 
belong  to  this  class.     They  have  already  been  considered  (p.  451.) 

The  next  important  member  of  this  class  is  the  potato  ;  of  very  subsidiary 
importance  as  food  are  beetroot  and  Jerusalem  artichoke.  Many  fruits 
yield  a  large  quantity  of  carbohydrates  (sugars),  but  they  cannot  be  con- 
sidered as  carbohydrate  foods  of  prime  importance. 

The  potato  is  the  tuber  of /So Zamtm  tuberosum,  and  is  an  absolute  necessity 
as  a  food  to  the  poor  peasantry  of  some  countries — as  Ireland.  Its  cultiva- 
tion free  from  disease,  to  which  it  is  very  subject,  is  of  great  economic  impor- 
tance to  these  people,  as  the  loss  of  the  potato  crop  means  starvation  to 
them. 

In  chemical  composition,  potatoes  show  a  small  proportion  of  proteids  and 
a  large  proportion  (for  a  fresh  food)  of  starch,  while  the  salts  consist,  as  in 
other  vegetable  foods,  of  an  excess  of  phosphates  and  potassium  over  sodium 
chlorides. 

The  juice  of  the  potato  is  acid,  due  to  the  vegetable  acids  (especially 
citrates),  partly  free  and  partly  in  combination  with  the  alkali  metals 
(potassium,  sodium,  calcium). 

As  a  food,  potatoes  yield  carbohydrates  and  act  as  an  antiscorbutic. 

Percentage  Composition 


- 

Water 

Proteid 

Fat 

Carbo- 
hydrate 

Cellulose 

Ash 

Proportion  of 
nit.  to  non-nit. 
foodstuffs  as 

Potatoes         .... 
Beet  {Beta  vulgaris) 
■Jerusalem  artichoke  {Lolimn 
tuberosum)  .... 

74-98 
82-25 

79-24 

2-08 
1-27 

1-76 

0-15 
0-12 

0-14 

21-01 
14-40 

16-29 

0-69 
1-14 

1-49 

1-09 
0-82 

1-08 

1  :  10-0 
1  :  11-4 

1:    9-3 

Potatoes  are  boiled  or  roasted  in  their  skins  so  that  none  of  the  salts  is 
lost ;  they  may  also  be  steamed. 

Examination  of  Potatoes. — The  quality  of  the  potato  is  judged  by  its  specific 
gravity  and  by  the  absence  of  the  fungus,  Phytophora  infestans,  which  causes 
'  potato  murrain.' 

Parkes  ^  gives  the  following  table  of  the  quality  of  potatoes  as  tested  by 
their  specific  gravity : — 


Below      1068 
Between  1068-1082 
Between  1082-1105 
Above      1105 
Above      1110 


The  quality  is  very  bad 
,,  inferior 

„  rather  poor 

,,  good 

,,  best 


Parkes  also  gives  the  following  ready,  if  somewhat  rough,  method  of  taking 
the  specific  gravity,  by  means  of  an  ordinary  urinometer  : — 

'  Op.  cit.  p.  300. 


472 


HYGIENE 


Take  a  sufficient  quantity  of  water,  and  dissolve  in  it  h  oz.  to  1  oz,  of 
salt,  and  take  the  specific  gravity ;  then  add  another  h  oz.  or  1  oz.  and 
take  the  specific  gravity  again.  The  operation  is  repeated  until  the  amount 
of  salt  added  is  found,  with  which  the  specific  gravity  will  be  definitely 
increased.  Then  salt  enough  may  be  added  to  bring  the  specific  gravity  up 
to  the  desired  amount,  i.e.  the  specific  gravity  of  the  potato. 

The  fungus  is  detected  by  the  microscope.  Partly  diseased  potatoes  may 
be  utilised,  either  by  obtaining  the  starch  from  them  by  washing  or  by  cutting 
in  thin  slices  and  drying  in  hot-air  chambers:  they  will  then  keep. 

Potatoes  may  be  preserved  by  peeling,  slicing,  and  placing  in  molasses  or 
drying  and  granulating. 


CLASS  IV 

This  class  of  vegetable  foods  contains  articles  of  diet  which  supply  water, 
vegetable  acids,  and  salts  to  the  organisms.  It  may  be  divided  into  two 
groups,  succulent  vegetables  and  fruits. 

To  all  succulent  vegetables  common  salt  is  added  in  the  cooking,  and  to 
the  majority  butter  is  a  valuable  addition.  Besides  the  nutritive  value  of 
vegetables,  there  is  another  use  and  not  an  unimportant  one  ;  they  give  relish 
to  the  food,  and  thus  act  like  the  other  food-accessories,  shortly  to  be  discussed. 
Of  these  the  different  varieties  of  salads  may  be  mentioned  :  lettuce,  endive, 
mustard  and  cress,  primrose,  and  dandelion,  with  onions  and  celery,  &c.,  which 
possess  pungent  aromatic  principles. 

Of  the  ordinary  vegetables  used  it  will  be  sufficient  to  give  the  composition 
of  turnips,  carrots,  cabbage,  spinach,  and  cauliflower  ;  the  other  vegetables 
are  closely  similar  in  composition. 

Percentage  Composition  of  Vegetables 


- 

Water 

Proteid 

Fat 

Carbohydrate 

Cellulose 

Salts 

1.  Turnips  (Brassicaraparajpifera) 

90-78 

1-18 

0-22 

5-89 

1-13 

0-80 

2.  Carrots  {Dcnicus  carota) 

86-79 

1-23 

0-30 

9-17 

1-49 

1-02 

3.  White   cabbage    (Brassica   oler- 

acea)         

80-97 

1-89 

0-20 

4-87  ' 

1-84 

1-23 

4.  Spinach  {Spinacia  oleracea) 

88-47 

3-49 

0-58 

4-44  - 

0-93 

209 

5.  CauHflower    {Brassica    oleracea 

botrijtis)   ..... 

90-89 

2-48 

0-34 

4-56^ 

0-91 

0-83 

The  absence  of  fresh  vegetables  in  a  diet  leads  to  the  production  of 
scurvy.  The  dried  vegetables  sold  are  antiscorbutic ;  they  are  serviceable 
for  making  soups,  hashes,  &c. 

Little  need  here  be  said  of  the  composition  of  fruits.  They  are  rich 
in  water,  vegetable  acids,  and  salts,  and  are  eminently  antiscorbutic  (espe- 
cially the  lemon).  Some  contain  large  quantities  of  sugar  (the  banana,  e.g.) ; 
others  are  rich  in  oil  (the  mature  cocoa-nut).  But,  except  for  their  anti- 
scorbutic properties  and  their  pleasant  taste,  they  are  quite  subsidiary  as 
articles  of  diet. 

Lemon-juice,  Lime-juice,  Vinegar 

1.  Lemoii-pdce  is  one  of  the  most  important  antiscorbutics,  and  its  use 
in  the  Navy  and  mercantile  marine  has  practically  eradicated  scurvy  from 
among  sailors. 

'  Consisting  of  2-29  per  cent,  sugar  and  2-58  per  cent,  other  carbohydrates. 
^  0-10  per  cent,  sugar,  4-34  per  cent,  other  carbohydrates. 
•  1-21  i^er  cent,  sugar,  3-34  per  cent,  starch,  &c. 


FOOD 


^73 


Both  lemon-  and  lime-juice  contain  a  large  proportion  of  citric  acid, 
with  some  malic  acid,  sugar,  and  proteid.  The  citric  acid  is  the  important 
constituent. 

Percentage  Comjoosition  of  Lemon-  and  Lime-juice. 


Total 
solids 


Lemon-juice,  fron  Citrus  limonwn 
Lime-juice,  from  Citrus  limctta 


'  8-597 
9-222 


Consisting  of 
Citric  acid  ,         Ash 


0-822 
7-201 


0-259 
0-419 


Sulpliurio 
acid 


0-002 
0002 


Sp.  feT-. 


10H2 
1035 


To  half  a  pint  of  lemon-juice  one  ounce  of  brandy  is  added  as  a  preserva- 
tive. When  administered  it  is  diluted  and  mixed  with  sugar.  The  daily 
quantity  to  be  taken  as  an  antiscorbutic  (when  fresh  vegetables  are  unpro- 
curable) is  one  ounce. 

Adulterations. — Both  lemon- and  lime-juice  areliableto  decomposition  and 
to  adulteration.  The  juice  ought  to  be  clear,  with  an  acid  but  not  bitter 
taste,  and  the  aroma  of  the  fruit. 

Lemon-juice  is  manufactured  :  a  solution  of  citric  acid  in  water  flavoured 
with  essence  of  lemon  is  made. 

The  juice  is  watered  ;  the  specific  gravity  and  the  acidity  (as  tested  by 
standard  alkaline  solution)  detect  this  adulteration. 

Sulphuric  acid  is  the  most  important  adulteration.  It  may  be  present  up 
to  0"434  or  even  0-825  per  cent.  (Hassall).  It  is  detected  by  acidulating  with 
hydric  chloride  and  adding  barium  chloride,  when  the  insoluble  barium 
sulphate  is  thrown  down. 

Hydrochloric  acid  and  nitric  acid  are  sometimes  added. 

Tartaric  acid  is  detected  by  adding  acetate  of  potassium  ;  on  standing, 
the  acid  potassium  tartrate  will  be  precipitated  in  crystals. 

2.  Vinegar  comes  under  the  same  heading  as  lemon -juice,  although  it  is 
not  so  powerful  an  antiscorbutic. 

Vinegar  is  of  two  kinds— wine  vinegar  and  malt  vinegar.  The  chief  varia- 
tion in  composition  is  the  amount  of  acetic  acid  (reckoned  as  glacial  acetic 
acid)  the  different  vinegars  contain.  The  percentage  of  acetic  acid  ought  not 
to  be  below  3  per  cent.  ;  in  the  best  vinegars  it  may  be  as  high  as  6  per  cent. 
A  small  quantity  of  sulphuric  acid  is  added  to  English  vinegar. 


Percentage  Composition  of  Vinegar 


- 

Sp.  Gr. 

Alooliol 

Extract 

Acetic 
acid 

Tartaric 
acid 

Tartar 

G-lycerine 

Ash 

Ordinary  vinegar  . 
Wine  vinegar 

1016-1019 
1015-1022 

trace 
1-05 

0-430 
1-066 

4-02 

5-77 

0-149 

0-124 

0-211 

0-113 
0-184 

Vinegar  is  diluted  with  water  ;  the  specific  gravity  (which  is  lowered)  and 
the  degree  of  acidity  detect  this. 

Sulphuric  acid  in  excess  is  detected  by  barium  chloride  and  hydrochloric 
acid.  Copper,  common  salt,  and  lead  may  be  detected  by  the  appropriate 
chemical  tests. 

The  use  of  vinegar  is  that,  like  other  vegetable  acids  (citric,  &c.),  it  tends 
to  maintain  the  alkalinity  of  the  blood  and  the  liquids  that  bathe  the  tissues. 

The  acetic  acid  is  converted  into  carbonate  in  the  body.  In  doses  of  from 
half  to  one  ounce  daily,  vinegar  is  an  antiscorbutic.  It  may  be  mixed  with 
the  food  and  even  taken  as  a  drink  when  much  diluted. 


474  HYGIENE 


ScuEVY  {Scorhuhis) 

Scurvy  is  an  important  disease  in  connection  with  food.  It  has  been 
several  times  referred  to.  Many  different  theories  have  been  brought  forward 
to  explain  the  pathology  of  the  disease,  but  none  of  these  can  be  considered 
quite  satisfactory.  In  scurvy  there  is  a  profound  change  in  the  blood,  the 
result  of  which  is  seen  in  effusion  of  blood  (ecchymoses)  in  various  parts  and 
in  fibrinous  exudation  in  the  muscles  and  gums,  and  in  a  condition  of  anaemia 
of  all  the  tissues.  There  seems  no  doubt  that  this  change  in  the  blood  is 
the  chief  pathological  factor  in  the  disease.  Speaking  from  a  chemical 
point  of  view,  a  change  in  the  blood  may  be  brought  about  either  by  an 
altered  nutrition  of  the  tissues  or  of  a  particular  tissue,  or  by  an  alteration 
in  the  quantity  and  quality  of  the  food  absorbed  into  the  blood-stream. 
There  is  much  evidence  to  show  that  the  change  of  the  blood  in  scurvy  is 
due  to  the  quantity  and  especially  to  the  quality  of  food  eaten.  Thus  we 
have  the  strong  evidence  of  scurvy  present  in  sailors  (at  a  period,  now  happily 
past),  who  for  long  periods  were  fed  both  insufficiently  and  with  a  diet  chiefly 
consisting  of  salt  pork  and  biscuit.  Here  the  deficiency  in  the  diet  was  that 
of  fresh  vegetables,  to  the  absence  of  which  scurvy  has  been  ascribed.  It  is 
known  that  on  a  diet  of  meat  and  fat  alone  scurvy  may  appear,  and  cereals 
and  the  seeds  of  Leguminosc^  have  no  antiscorbutic  power.  The  food 
principle  in  vegetables  to  which  are  ascribed  antiscorbutic  property  are 
the  vegetable  acids — citric,  tartaric,  acetic,  malic,  lactic — and  there  is  some 
reason  for  this.  According  to  Busk  and  Garrod,  the  deficiency  of  potash 
in  the  system  is  the  basis  of  scurvy  :  potassium  salts  (except  those  of  vegetable 
acids)  are,  however,  not  antiscorbutic. 

Ealfe  states  that  the  alkaline  salts  of  the  blood  in  scurvy  are  absolutely 
decreased.  Now  the  chief  source  of  alkalinity  in  the  body  are  the  vegetable 
acids  just  mentioned,  for  they  are  changed  into  carbonate  in  the  system  and 
combine  in  this  state  with  potassium  and  sodium,  thus  forming  alkaline  salts. 
Add  to  tliis  the  fact  that  articles  of  diet  containing  these  acids  or  their  salts 
are  the  best  antiscorbutics,  and  we  are  almost  driven  to  the  conclusion  that 
it  is  the  absence  of  those  important  principles  in  the  food  which  is  the 
main  cause  of  scurvy,  especially  as  this  absence  means,  as  a  rule,  a  general 
deficiency  of  the  diet.  This  idea  is  not  against  the  fact  that  fresh  meat  may 
also  be  antiscorbutic,  because  fresh  meat  contains  a  fair  quantity  of  sarco- 
lactic  acid. 

The  following  may  be  mentioned  as  antiscorbutics  : — Fresh  vegetables,  such 
as  potatoes,  cabbage,  cauliflower  ;  fresh  fruit ;  lemon-juice  ;  dried  vegetables, 
although  these  are  not  so  useful  as  fresh ;  vinegar  ;  and  the  alkaline  salts  of 
the  vegetable  acids,  these,  however,  not  being  nearly  so  useful  as  good  lemon- 
or  hme-juice. 

FOOD-ACCESSORIES 

Almost  as  important  to  civilised  man  as  the  foodstuffs  which  are  necessary 
for  existence  are  substances  which  enable  the  food  to  be  taken  with  relish ; 
such  substances  may  appropriately  be  called  food-accessories.  These  in 
many  instances  contain  aromatic  bodies,  to  which  their  action  is  due.  The 
smell  of  well-cooked  meat  is  decidedly  appetising  ;  the  absence  of  aroma  in 
badly  cooked  or  over- cooked  meat  certainly  diminishes  its  consumption. 
Many  other  substances  act  as  relishing  agents  through  the  aromatic  bodies 
contained  in  them,  the  effect  in  the  brain  through  the  special  senses  affecting 
the  digestive  organs.     On  the  other  hand,  some  of  these  food-accessories  have 


FOOD  475 

a  special  action  on  the  central  nervous  system,  a  stimulant  or  a  sedative 
effect,  which  is  in  some  cases  their  chief  action.  Such  food-accessories  are 
alcohohc  beverages,  tea,  coffee,  &c.  A  third  action,  which  may  be  ascribed 
to  food-accessories,  is  that  of  affecting  the  secretion  of  the  digestive  juices, 
and  of  acting  directly  on  the  chemical  processes  of  digestion. 

It  is  not  surprising  that,  with  increase  of  civilisation  and  its  attendant 
high  development  of  the  special  senses  and  the  central  nervous  system, 
special  stimulants  of  these  parts  of  the  nervous  system  should  be  in  common 
use.  But  it  is  a  remarkable  fact  that  the  use  of  food-accessories  having  such 
effects  as  have  been  described  is  universal  in  the  world,  in  savage  as  well 
as  in  civilised  nations.  The  civilised  man  has  the  advantage  over  the  savage 
in  the  refinement  of  his  food-accessory  stimulants,  but  not  in  the  quantity 
of  them  he  utilises. 

We  may,  from  what  has  been  said,  usefully  divide  food-accessories  into 
aromatic  principles  (which  affect  the  digestive  system  through  the  central 
nervous  system),  into  those  which  directly  affect  the  central  nervous  system 
after  being  absorbed,  and  into  those  which  directly  affect  the  digestive  system. 
The  aromatic  principles  are  often  associated  with  substances  which  have  one 
or  other  of  the  two  last  actions. 

As  examples  of  the  aromatic  principles,  we  may  cite  the  aroma  of  cooked 
meat,  especially  roasted  meat,  an  aroma  due  to  an  imisolated  principle, 
sometimes  called  osmazome.  The  aroma  differs  in  each  variety  of  meat ; 
that  of  beef  is  different  from  that  of  mutton,  of  goat's  flesh,  of  pork,  &c. ;  the 
cooked  blood,  too,  has  a  different  aroma  in  each  animal.  This  actual  aroma 
is  most  marked  in  animal  foods  ;  with  ordinary  vegetable  foods,  as  a  rule,  it 
is  less  marked.  The  taste  of  well-made  bread  (the  '  nutty '  flavour)  is  a 
well-marked  characteristic  of  it,  and  is  no  doubt  not  only  due  to  an  aromatic 
principle,  or  aromatic  principles,  but  also  to  the  mixture  of  dextrine, 
starch,  &c.,  with  sugar  and  the  acids  which  have  been  described  as  the  pro- 
ducts of  the  activity  of  yeast.  Most  of  the  other  cereals  have  little  aroma, 
and  flavouring  agents  are  usually  added  to  them,  the  commonest  being- 
butter  and  common  salt.  The  leguminous  seeds  have,  as  a  rule,  a  well- 
defined  aroma.  Some  other  vegetable  products  are  used  almost  solely  as 
food-accessories,  such  as  onions,  spices,  &c.  These,  however,  have  probably 
another  and  more  important  action,  viz.  that  of  directly  stimulating  the  flow 
of  the  digestive  juices  ;  a  subject  to  be  considered  later. 

To  the  second  class  of  food-accessories  which  we  have  made  belong  the^ 
most  important  articles  of  diet  under  this  heading,  viz.  those  which  have  an. 
effect  on  the  central  nervous  system ;  such  as  all  alcoholic  beverages,  tea, 
coffee,  cocoa,  &c.,  and  beef-tea  to  a  less  degree.  They  all  have,  however, 
properties  which  would  entitle  them  to  be  placed  under  all  three  classes  of 
food-accessories.  For  not  only  do  they  act  on  the  central  nervous  system,, 
but  they  often  possess  a  delicate  aroma,  and  they  have,  as  we  shall  see,  a. 
powerful  effect  on  the  digestive  juices  and  the  chemical  processes  of  digestion. 
But  there  seems  little  doubt  that  the  object  for  which  they  are  taken  by 
mankind  is  that  of  affecting  the  central  nervous  system. 

This  they  do  in  two  ways :  small  doses  stimulate,  large  doses  depress  ; 
medium  doses  may  be  said  to  act  as  a  sedative.  In  the  alcoholic  beverages; 
these  effects  are  due  to  the  alcohol  present  in  them  ;  in  tea,  coffee,  cocoa,  &c., 
they  are  due  to  the  active  principles  caffeine  and  theobromine.  Both  alcoholic 
beverages  and  tea,  and  its  congeners,  have  other  effects  besides  those  due- 
to  their  respective  active  principles.  These  effects  are,  however,  best  consi- 
dered under  another  heading. 


476  HYGIENE 

It  is  difficult  to  give  physiological  reasons  for  the  custom  of  taking  cere- 
bral stimulants  and  sedatives  as  food-accessories.  If  it  is  not  simply  a 
question  of  morals,  as  some  consider  it  is,  one  explanation  may  be  given.  Man, 
both  in  the  savage  and  in  the  civilised  state,  is  accustomed  to  eat  large  meals, 
which  tend  to  diminish  the  activity  of  the  central  nervous  system,  and  thus  to 
diminish  the  digestion  of  the  ingested  food.  Cerebral  stimulants  may  by 
keeping  up  the  activity  of  the  central  nervous  system  aid  in  the  prolonged 
digestion  of  a  large  meal.  It  is  not  simply  that  alcoholic  stimulants,  to  take 
an  example,  in  moderate  doses  increase  the  How  of  the  digestive  juice,  and 
thus  aid  digestion,  because  a  slight  excess  of  the  ordinary  alcoholic  drinks, 
as  we  shall  see,  actually  retards  the  chemical  processes  of  digestion.  The 
explanation  given  seems,  according  to  our  present  knowledge,  the  only  likely 
one,  though  evidently  it  is  not  complete. 

The  third  class  of  food-accessories  is  an  important  one.  The  natural 
aroma  of  foods  is,  as  Ave  have  said,  appetising  ;  this  appetising  action,  which 
may  aft'ect  the  brain  through  the  special  senses  of  the  eye  or  nose,  is  asso- 
ciated with  a  How  of  the  salivary  secretion,  and  a  corresponding  flow  of  gastric 
juice.  The  food-accessories  we  are  now  considering  have  a  similar  stimulat- 
ing action  on  the  digestive  juices  when  they  are  ingested.  Small  doses  of 
alcohol,  for  example,  increase  the  flow  of  gastric  juice,  and  thus  act  as  a  dis- 
tinct aid  to  digestion.  Small  quantities  of  soups  and  beef-tea  probably  act 
in  the  same  way,  and  although  there  is  no  very  definite  knowledge  on  the 
subject,  spices,  hot  flavouring  agents  and  onions,  &c.,  are  considered  to  have 
,  a  similar  action.  Schiff,  indeed,  affirms  that  it  is  necessary  that  certain 
substances  (peptogens)  should  be  absorbed  before  the  gastric  juice  can  be 
secreted  ;  among  such  substances  are  dextrine  and  peptones.  This,  however, 
is  doubtful. 

Not  only,  however,  have  this  class  a  stimulating  effect  on  the  salivary  and 
gastric  secretions,  but  they  stimulate  in  many  cases  the  muscular  movements 
of  the  stomach.  Alcohol  and  spices  probably  have  this  action.  On  the 
other  hand,  they  have  by  many  experiments  been  shown  to  have  a  powerful 
retarding  effect  on  the  chemical  processes  of  digestion. 

The  experiments,  the  results  of  which  will  presently  be  detailed,  were  all 
performed  outside  the  body  ;  they  were  artificial  digestions.  A  great  dis- 
tinction must  be  drawn  between  digestive  experiments  outside  the  body  and 
the  actual  processes  occu.rring  in  the  stomach,  which  is  the  organ  that  now 
concerns  us,  inasmuch  as  it  is  the  receptacle  of  the  food.  For  the  stomach 
is  an  organ  in  which  not  only  the  chemical  process  of  digestion  is  progressing, 
but  the  products  of  digestion  (peptones,  &c.),  the  salts,  and  the  diffusible 
bodies  taken  in  with  the  food  (such  as  alcohol,  tea,  &c.),  are  constantly  being 
absorbed.  When  we  speak,  therefore,  of  a  certain  percentage  of  a  substance 
hindering  digestion  in  a  test  tube,  it  is  not  accurate  to  apply  the  results  ob- 
tained directly  to  the  phenomena  of  digestion  in  the  stomach.  But  although 
this  is  so,  yet  valuable  dietetic  deductions  may  be  drawn  from  the  results  of 
experiments  on  artificial  digestion.  Sir  "William  Roberts,  W.  Fraser,  Bikfalvi, 
and  others  have  made  experiments  in  this  direction,  and  the  conclusions  arrived 
at  have  been  closely  similar.  On  the  digestion  of  starch  by  the  saliva,  Eoberts 
found  that  the  distilled  spirits,  coffee,  and  cocoa  had  practically  no  effect 
when  these  substances  were  used  in  quantities  which  would  be  considered  as 
dietetic  doses.  On  the  other  hand,  tea  and  wines  of  all  kinds  had  a  powerful 
retarding  effect  on  the  digestion  of  starch — an  effect,  in  the  case  of  tea,  not 
due  to  the  volatile  oil,  or  the  theine  (caffeine),  but  probably  due  to  the  taimin. 
In  the  cases  of  wines,  the  effect  was  probably  due  to  the  acidity  of  the  wines ; 
sahvary  digestion  is  not  active,  as  is  well  known,  in  a  distinctly  acid  medium. 


FOOD  in 

The  effect  of  food-accessories  on  gastric  digestion  is  much  more  important 
than  that  on  salivary  or  pancreatic  digestion.  Salivary  digestion  is  of  minor 
importance  in  man,  whereas  the  preparation  and  digestion  of  the  food  in  the 
stomach  are  of  vast  importance.  If  gastric  digestion  is  too  much  delayed, 
there  is  a  liability  to  the  occurrence  of  various  forms  of  bacterial  fermenta- 
tion (the  butyric  acid  fermentation,  &c.),  which  lead  to  gastric  disturbance 
and  malassimilation  of  the  food. 

Eoberts  ^  and  others  have  shown  that  in  artificial  gastric  digestion 
proof  spirit  ^  has  no  appreciable  effect  unless  it  is  present  to  the  extent  of  10 
per  cent,  of  the  mixture.  Twenty  per  cent,  of  proof  spirit  added  to  the  digest- 
ing mixture  causes  a  well-marked  retardation  of  the  fermentative  process, 
while  if  50  per  cent,  be  added  the  activity  of  the  ferment  is  paralysed.  Proof 
spirit,  brandy,  whisky,  and  gin  (the  distilled  spirits)  affect  gastric  digestion 
only  in  proportion  to  the  amount  of  alcohol  they  contain.  If  we  inquire 
what  dose  of  these  ardent  spirits  is  requisite  to  retard  digestion  in  the  stomach, 
we  find  that  a  much  larger  quantity  is  necessary  to  do  this  than  is  ordinarily 
taken.  Thus,  taking  the  average  mass  of  food  in  the  stomach  as  about  two 
pounds,  a  dose  of  two  ounces  of  average  brandy  would  be  equivalent  to  only 
5  per  cent,  of  proof  spirit  in  the  mixture— a  proportion  which  does  not  appre- 
ciably affect  the  chemical  process  of  digestion.  It  is  also  to  be  remembered 
that  even  this  quantity  of  brandy  does  not  represent  5  per  cent,  of  proof 
spirit  for  any  length  of  time  in  the  stomach,  for  the  diffusible  alcohol  is 
constantly  being  absorbed ;  larger  doses  of  brandy  than  two  ounces  would 
therefore  probably  not  affect  the  process  of  fermentation.  We  may  therefore 
conclude  that  as  food-accessories  the  ardent  spirits  (brandy,  whisky,  gin) 
have  a  twofold  action  ;  they  stimulate  the  secretion  of  gastric  juice  when 
taken  in  small  quantities,  they  retard  gastric  digestion  when  taken  in  intoxi- 
cating doses,  dietetic  doses  having  no  effect  in  this  direction. 

The  effect  of  wines,  malt  liquors,  tea,  coffee,  &c.,  and  beef-tea,  and  whey 
is  quite  different  from  that  of  the  ardent  spirits.  To  some  extent,  when 
taken  in  small  doses,  they  act  as  stimulants  to  the  secretion  of  gastric  juice, 
but  they  all  have  a  well-marked  retarding  effect  on  the  chemical  process  of 
gastric  digestion.  In  the  case  of  wine  and  malt  liquors,  this  retarding  effect 
is  not  proportional  to  the  amount  of  alcohol  contained  in  them ;  there  is 
something  else  present  which  is  more  retarding  than  alcohol.  Of  the  wines, 
sherry  and  port  wine  have  the  most  retarding  effect.  Thus  20  per  cent,  of  the 
sherry  which  was  used  (equal  to  8  per  cent,  of  proof  spirit)  added  to  the  diges- 
tive mixture  trebled  the  time  of  normal  digestion.  A  proportion  of  40  per  cent. 
(16  per  cent,  proof  spirit)  completely  stopped  digestion.  These  results  differ 
from  those  described  as  due  to  alcohol  pure  and  simple.  As  Eoberts  points 
out,  the  use  of  half  a  pint  of  sherry  at  dinner  would  make  a  mixture  in  the 
stomach  containing  25  per  cent,  of  the  wine  ;  a  proportion  which,  as  we  have 
just  seen,  markedly  retards  the  process  of  digestion.  Such  a  habit,  therefore, 
can  only  be  deleterious. 

Hock,  claret,  and  champagne  (containing  from  10  to  12  per  cent,  of 
alcohol)  have  a  less  retarding  effect  than  port  or  sherry  ;  and  champagne 
has  a  less  effect  than  the  first  two  wines  mentioned.  Twenty  to  40  per 
cent,  of  the  wines  in  the  digestive  mixture  hinders  digestion ;  an  effect  out 
of  proportion  to  the  alcohol  they  contain,  which  would  only  be  present  in 
the  proportion  of  2  to  4  per  cent.     The  effect  of  malt  Hquors  on  peptic 

'  Dietetics  and  Dyspepsia,  London,  1885. 

2  Proof  spirit  contains  by  weight  49-3  per  cent,  of  absolute  alcohol  and  57-09  per  cent. 
by  volume ;  a  10  per  cent,  mixture  may  therefore  be  considered  as  containing  approxi- 
mately 5  per  cent,  of  absolute  alcohol. 


478  HYGIENE 

digestion  is  more  marked  than  that  of  these  light  wines,  but  is,  as  in  their 
case,  out  of  proportion  to  the  alcohol  they  contain.  Ten  per  cent  of  '  light 
English  table  beer  '  and  of  lager  beer  added  to  the  digestive  mixture  did  not 
delay  digestion  ;  but  a  retarding  effect  was  noticed  when  20,  40,  and  GO 
per  cent,  of  these  liquors  were  added.  These  percentages  represent  only 
about  1,  2,  and  3  per  cent,  of  alcohol.  Beer  is  often  drunk  in  large 
quantities  at  meals,  and  Eoberts  considers  that  it  must  often  be  present 
in  the  stomach  contents  in  the  proportion  of  50,  GO,  or  even  80  per 
cent.  Such  proportions  would  distinctly  retard  the  chemical  process  of 
digestion. 

Tea,  coffee,  and  cocoa  all  retard  gastric  digestion,  and  cafe  noir  (to  the 
extent  of  10  per  cent.)  was  very  powerful  in  this  respect.  Beef-tea  retards, 
whey  to  a  less  extent. 

The  retarding  effect  on  digestion  of  the  food-accessories  is  ascribed  by 
Sir  William  Eoberts  to  the  presence  in  the  liquids  of  the  salts  of  organic  acids 
and  of  neutral  inorganic  salts — speaking  more  particularly  to  lactates  and  sar- 
colactates  (in  beef-tea)  and  to  the  chlorides  of  potassium  and  sodium.  When 
salts  of  the  organic  acids  (lactates,  butyrates,  &c.)  are  taken  into  the  stomach, 
they  are  decomposed  by  the  hydrochloric  acid  of  the  gastric  juice,  by  which, 
therefore,  the  organic  acids  are  set  free.  Gastric  digestion  is  most  active  in 
the  presence  of  free  hydrochloric  acid,  and  although  the  presence  of  a  small 
proportion  of  free  organic  acids  in  the  stomach  contents  does  not  stop  diges- 
tion, it  tends  to  hinder  the  activity  of  the  pepsin.  The  development  of  these 
acids  probably  explains  the  retarding  effect  of  beef-tea  and  whey  on  digestion, 
since  hyperacidulation  by  means  of  hydrochloric  acid  brings  the  activity  of  the 
digestion  almost  up  to  the  normal  in  the  presence  of  these  food-accessories. 
Hyperacidity  of  the  digestive  mixture  does  not  counteract  the  retarding  effect 
of  light  wines  and  of  Burton  ale  on  digestion  ;  and  with  port  or  sherry  it 
actually  aggravates  the  retardation.  The  retarding  effect  on  digestion  of 
wines  and  malt  Hquors  is  not,  therefore,  due  to  organic  acids,  but  probably 
in  part  to  the  neutral  inorganic  salts  present.  The  question,  hoAvever,  is  not 
settled. 

It  is  interesting  to  note  that  Eoberts  found  effervescent  water  to  be  a  slight 
stimulant  to  the  chemical  processes  of  gastric  digestion  ;  a  result  expHcable 
on  the  consideration  of  the  evolution  of  bubbles  of  carbonic  acid  gas  agitating 
the  digesting  mixture. 

On  pancreatic  digestion  the  effect  of  food-accessories  is  interesting. 
Eoberts  found  that  the  retarding  effect  of  wines,  beer,  and  tea  on  the  pan- 
creatic digestion  of  starch  was  due  to  the  acidity  of  these  beverages  ;  if  the 
acidity  were  neutralised,  as  it  is  normally  in  the  duodenum,  they  had  no 
retarding  effect. 

The  effect  of  the  food-accessories  on  the  pancreatic  digestion  of  proteids 
was  found  to  be  practically  nil.  Tea  and  coffee  had  no  appreciable  effect, 
and  the  digestion  of  milk  was  only  slightly  interfered  with  by  10  per  cent, 
of  proof  spirit.  A  large  percentage  of  alcohol  is  probably  never  present  in 
the  duodenal  contents,  since  it  is  so  readily  absorbed  from  the  stomach. 

The  general  action  of  the  food-accessories  which  has  just  been  discussed 
is  accompanied  by  special  actions  of  individual  food-accessories  which  are 
more  appropriately  discussed  under  each  separate  heading.  It  may  be  well 
here  to  discuss  certain  conclusions  from  the  facts  concerning  the  general 
action  of  food-accessories  which  have  just  been  discussed. 

1.  As  to  the  aroma  of  food  and  the  use  of  so-called  condiments.  Those 
who  can  easily  procure  a  sufficiency  of  food  can  also  produce  a  variety,  and 
there  is  evidence  to  show  that  a  variation  in  the  articles  of  diet  used,  although 


FOOD  479 

one  may  be  as  nutritious  as  the  other,  is  of  great  service  in  preserving  health. 
The  lower  animals,  and  probably  the  lower  races  of  mankind,  can  subsist 
on  monotonous  food ;  but  civilised  man  seems  to  require  variety.  This 
variety  includes  variation  in  the  different  aromatic  principles  present  in  foods, 
variations  in  the  mode  of  cooking,  and  variations  in  the  condiments,  spices, 
pepper,  vinegar,  &c.,  added  to  the  food  in  the  cooking.  Such  facts  are  im- 
portant to  bear  in  mind  in  connection  with  public  institutions  and  bodies 
of  men  where  all  are  supplied  with  the  same  kind  of  food,  and  where  economy 
has  to  be  considered. 

Monotony  of  food,  the  bad  cooking  of  food,  or  the  non-addition  of  condi- 
ments (which  are  very  cheap)  may  lead  to  disgust  and  refusal  of  food  or  to 
disordered  digestion.  As  examples  of  the  difference  in  this  respect  between 
foods  of  similar  composition  may  be  cited  bread  and  biscuits  :  good  bread  is 
never  tired  of  during  one's  lifetime  ;  good  biscuits  if  eaten  for  any  length  of 
time  are  refused  at  last.  So  with  well-cooked  fresh  meat  and  the  over-cooked 
tinned  meat ;  the  first  is  greatly  superior  to  the  latter  as  an  article  of  diet. 

2.  We  shall  have  to  discuss  the  possible  useful  action  of  those  food-acces- 
sories which  act  on  the  central  nervous  system  under  the  separate  headings 
of  alcoholic  beverages,  tea,  &c.  One  possible  explanation  of  their  utility  has 
already  been  brought  forward  (p.  476). 

3.  With  regard  to  the  retarding  effect  on  digestion  of  many  of  the  food- 
accessories,  it  has  been  suggested  by  Sir  William  Eoberts  that,  anomalous 
as  it  may  seem,  the  retardation  may  be  in  many  instances  of  actual  benefit 
to  the  absorption  of  food.  Thus  in  the  case  where  large  meals  are  eaten,  with 
which  these  digestion-retarding  food-accessories  (soup,  beer,  wines)  are  often 
taken  in  fairly  large  quantities,  the  retardation  of  digestion  may  be  of  benefit 
in  allowing  the  food  to  be  more  completely  digested  and  absorbed.  The 
length  of  time  food  remains  in  the  stomach  varies  according  to  the  quantity 
and  kind  of  food,  and  whether  the  meal  taken  has  consisted  of  one  article  of 
diet  or  is  a  mixed  meal.  Tliis  has  been  already  discussed  (p.  419).  Leube,* 
experimenting  on  healthy  persons,  found  that  after  an  average  meat  meal 
the  stomach  was  not  completely  empty  under  seven  hours.  This,  however, 
is  against  what  we  know  from  the  experiments  of  Beaumont  and  Richet. 
Leube's  estimate  is  too  high.  It  is,  moreover,  probable  that  the  time  of 
digestion  of  a  particular  meal  (or  rather  the  time  in  which  it  is  expelled 
from  the  stomach)  varies  not  only  in  each  person,  but  in  different  bodily 
conditions  of  the  same  person.  No  exact  statement  on  this  point  can  thus 
be  made.  But  from  such  a  consideration  it  is  likely  that  the  retarding 
effect  on  digestion  of  food-accessories  may  be  reduced  to  a  minimum  (e.g.  in 
persons  of  very  vigorous  digestion)  by  the  great  rapidity  of  natural  digestion, 
by  increased  rapidity  of  absorption,  and  by  the  activity  of  the  muscular  walls 
of  the  stomach.  The  results  of  experiments  in  test  tubes  on  the  retarding 
effect  of  food-accessories  must  not  be  too  rigidly  applied  to  particular  indi- 
viduals. These  experiments  show  what  might  have  taken  place  in  certain, 
perhaps  abnormal,  conditions,  which  are  perhaps  more  interesting  to  the 
physician  than  to  the  student  of  Public  Health. 

I.    CONDIBIEKTS 

Many  food-accessories  may  be  grouped  together  as  '  condiments,'  since 
they  are  added  to  food  as  flavouring  agents.  These  are  such  as  mustard, 
pepper,  onions  and  vegetables  allied  to  them,  pimento,  cloves,  cinnamon, 
nutmeg,  caraway,  cardamoms.     Vinegar   and  common  salt  are  also  con- 

'  Deutsche  Archiv  f.  hlin.  Med.  Bel.  xxxiii.  1883. 


480  HYGIENE 

diments.  The  former  has  akeady  been  considered  (p.  478),  and  the  uses  of 
common  salt  have  been  frequently  discussed. 

Tiie  condiments  now  under  consideration — pimento,  cloves,  cinnamon, 
&c. — owe  their  action  as  food-accessories  to  the  aromatic  oils  they  contain. 
Oil  of  mustard  and  piperin,  the  active  principle  (resin)  of  pepper,  have  an 
action  similar  to  the  aromatic  oils.  This  action  is  manifold.  The  active 
principles  are  first  antiscj^tic  (oil  of  mustard  is  powerful  in  this  respect),  so 
that  they  serve  the  useful  purpose  when  taken  with  a  large  mixed  meal  of 
tending  to  prevent  acid  fermentation  in  the  digestive  tract.  They  are  also 
stimulants  of  tlie  secretion  of  the  ditjestive  juices  ;  they  certainly  stimulate 
salivary  secretion,  and  thus  reflexly  (also  probably  directly)  the  secretion  of 
gastric  juice.  Thirdly,  they  stimulate  peristaltic  action.  Taken  in  quantity 
and  by  themselves,  some  of  them  (such  as  cloves  and  pimento)  act  as  stimu- 
lants to  the  nervous  system  ;  but  this  is  not  an  action  associated,  as  a  rule, 
with  their  rule  as  food-accessories. 

Fcppcr. — Black  pepper  is  obtained  from  Piper  nigrum  ;  white  pepper  is  the 
same  decorticated.  Both  occur  in  commerce  as  '  seeds  '  and  in  powder,  and 
the  latter  is  liable  to  adulteration.  In  black  pepper,  free  of  water  and  of 
sand,  the  amount  of  piperin  and  fixed  oil  is  about  7"87  per  cent.,  and  the 
amount  of  carbohydrate  transformable  into  sugar  is  49'33  per  cent.,  not  less. 
This  quantity  of  carbohydrate  may  be  taken  as  a  test  of  the  purity  of  the 
pepper.  In  white  pepper,  fixed  oil  and  piperin  is  8*24  per  cent.,  and  carbo- 
hydrates are  64-95  per  cent.,  of  which  4(5-72  per  cent,  are  starch. 

Pepper  is  adulterated  with  olive  stones,  spent  ginger,  palm-nut  powder, 
rape  seeds,  and  mustard  husks.^ 

Mustard  is  the  seed  of  the  Sinapis  alba  and  Sinapis  nigra.  It  is  sold  in 
powder,  which  is  liable  to  adulteration,  being  mixed  with  different  kinds  of 
starchy  flours  (such  as  wheaten  flour,  barley  flour,  and  linseed).  These 
adulterations  are  detected  by  the  microscope  (see  pp.  451-454).  Turmeric 
is  also  added. 

Pure  mustard  contains  0-66  per  cent,  of  volatile  oil,  35-42  per  cent,  of 
fixed  oil,  and  13-95  per  cent,  of  carbohydrates.  The  carbohydrates  in 
adulterated  mustard  are  as  high  as  67  per  cent,  sometimes,  the  fixed  oils  in 
such  specimens  being  below  7  per  cent.' 

2.   FOOD-ACCESSOEIES    TaKEN   AS   LIQUIDS 

The  food-accessories  taken  in  a  liquid  form  may  be  divided  into  two 
groups  :  (1)  the  liquids  containing  alcohol ;  beer,  wine,  &c. ;  (2)  the  liquids 
containing  the  active  principles  caffeine  or  theobromine  ;  such  as  tea,  cofiee, 
Paraguay  tea,  cocoa. 

1.  Alcoholic  Beverages 

These  owe  their  action  as  food-accessories  chiefly  to  the  ethylic  alcohol 
they  contain  ;  and  the  effect  of  the  difl'erent  kinds  of  alcoholic  drinks  is, 
broadly  speaking,  proportional  to  the  amount  of  alcohol  present,  but  not 
completely  so,  since  the  majority  of  alcoholic  drinks  owe  part  of  their  efi'ect 
to  the  action  of  aromatic  substances  and  certain  other  principles,  which  will 
be  discussed  afterwards.  Although,  therefore,  the  amount  of  alcohol  jjresent 
is  important,  yet  the  presence  of  these  other  principles  must  be  considered 
also  in  deciding  the  utility  or  non-utility  of  any  given  alcoholic  drink. 

The  use  of  alcohol  to  mankind  dates  from  time  immemorial ;  it  is  so 
readily  produced  from  sugars  and  starches  by  fermentation  that  its  early  dis- 

'  See  Konig,  op.  cit.  Bd.  i.  pp.  731-735.    Also  Hassall's  Food  and  its  Adulterations. 
2  See  Konig,  op.  cit.  Bd.  i.  p.  739. 


FOOD 


481 


■covery  by  the  human  race  is  not  to  be  wondered  at.  Its  use,  too,  in  tlie 
world  is  so  widespread  that  the  manufacture  of  alcohoHc  drinks  has  become 
an  important  industry  in  civilised  countries,  and  the  tax  on  its  production 
an  important  addition  to  the  revenue  of  these  countries.  It  would  be  out  of 
place  here  to  inquire  whether  this  extended  use  of  so  powerful  an  agent  is 
■of  benefit  to  the  social  well-being  of  the  community.  The  introduction  of 
alcoholic  beverages  into  savage  or  semi-savage  communities  leads  rapidly  to 
the  extinction  of  the  aborigines,  and  to  the  abuse  of  alcohol  must  be  as- 
cribed a  large  proportion  of  crime  and  immorality.  A  great  mortality 
attends  the  class  of  inebriates  when  they  are  attacked  by  infectious  disease 
.and  by  pneumonia  or  when  they  meet  with  severe  accidents.  The  question, 
however,  for  consideration  here  is  the  physiological  effect  of  alcohohc 
beverages,  and  what  value  they  may  possess  in  civilised  communities. 

Classification  and  Composition  of  Alcoholic  Beverages. — For  the  sake  of 
convenience,  and  also  according  to  the  amount  of  alcohol  they  contain, 
alcoholic  drinks  may  be  divided  into  (1)  beers,  (2)  light  wines  (red,  and  white), 
(3)  sweet  wines  (champagne,  port,  sherry,  &c.),  and  (4)  spirits  (brandy, 
whisky,  &c.). 

1.  Percentage  Composition  of  Beers 


- 

Sp.gr. 

Water 

CO, 

Alcohol. 

Wt.  per 

cent. 

Ex- 
tract 

Proteid 

Sugar 

Dex- 
trine 

Acid 
(lactic) 

Salts 

Phos- 
phoric 
acid 

Lager  beer . 
Bock  beer  . 
Ale     . 
Porter 

1-0162 
1-0213 
1-0141 
1-0191 

90-08 

87-87 
89-42 
88-49 

0-196 
0-234 
0-201 
0-215 

3-93 

4-69 
4-73 
4-70 

5-79 
7-21 
5-65 
6-59 

0-71 
0-73 
0-61 
0-65 

0-88 
1-81 
1-07 
2-62 

3-73 
3-97 
1-81 
3-08 

0-151 
0-165 
0-278 
0-281 

0-228 
0-263 
0-310 
0-363 

0-777 
0-089 
0-086 
0-093 

The  sugar  and  dextrine  in  beer  render  it  liable  to  fermentation,  during 
which  free  acids  (acetic,  &c.)  are  formed.  The  salts  of  beer  consist  of 
chlorides  and  phosphates  of  potassium  and  sodium  and  of  calcium.  Besides 
the  alcohol,  the  most  important  principle  present  in  beer  is  derived  from  the 
hops  used,  especially  the  lupulin  (see  Physiological  Action  of  Bbee,  p.  486). 

2.  The  light  wines,  and  the  sparkling,  differ  slightly  in  the  amount  cf 


Percentage  Composition  of  Light  Wines 

(Bed  and  White) 

- 

ho 
P. 

m 

"o  o 

1 

CD 

a 
1 

s 

ba 
o 

§  «  g 

HI 

w 

W 

o 

W 
M 

Moselle      .... 

0-9964 

7-99 

2-24 

0-790-72 

0-031 



0-175  0-036 

0-0260-0681 

Rhine  wine 

1          1          1 

White 

1-0005 

8-00 

2-60'0-8ll0-85 

0-048 



0-230  0-04610-020,0-0851 

Eed  . 

0-9966 

10-08 

3-04  0-52 

— 

— 

0-158 

0-249 



— 

— 

Prench  wine 

Eed  . 

0-9982 

7-80 

2-56  0-57'0-73;0-043 

0-180 

0-248  0-030[0-033  0-106 

White 

0-9963 

10-31 

3-03i0-66  0-97 

— 

— 

0-250  0-032  0-038,0-098 

Lower  Austrian  wine 

White 

0-9949 

7-93 

2-13 

0-67  0-68  0-022 

— 

0-189  0-034 

0-039'0-081 

Eed  . 

0-9958 

8-49 

2-54 

0-62  0-81 0-026 

0-110 

0-241 0-037 

0-033  0-101 

Hungarian  wine 

Eed  . 

0-9952 

9-02 

2-54 

0-67  0-79  0-034 

0-150 

0-215  0-038 

0-0240-091 

White 

0-9955 

8-00 

2-33,0-69  0-77  0-027 

— 

0-204  0-034 

0-025  0-075 

Italian  wine       . 



10-63 

3-44  0-52  1-45  0-013 



0-2900-032 

0-0190-115 

Spanish  wine 

Eed. 

— 

12-31 

3-53  0-49  1-09 

— 

0-220 

0-610  0-027  0-221|0-242 

Australian  wine  contains  from  13  to  14  per  cent,  of  alcohol  by  weight,  16  to  17  per 
cent,  by  volume. 

VOL.   I.  II 


482 


HYGIENE 


ethylic  alcohol  they  contain,  but  much  more  in  the  quantity  of  ethers  and 
aromatic  substances  present.  Red  and  white  wines  are  obtained  from 
France,  Germany,  Austria,  Hungary,  Italy,  and  Spain,  and  also  from  Aus- 
tralia.    The  best  sparkling  wines  (champagnes)  are  from  France. 

3.  Although  champagnes  differ  from  port  and  sherry  in  their  effect,  yet 
they  are  best  classed  under  the  same  heading  as  sweet  wines,  owing  to  the 
amount  of  sugar  they  contain. 

Percentage  Composition  of  Sweet  Wines 


. 

02 

13 
§ 

1 

5 

H 

tlO 

00, 

Mineral 

salts 

pT       h" 

o 

Champagnes 

:         '       i 

I-    j 

Veuve  Cliquot   . 

1-0565  10-20 19-75  0-60  1-13 

0-25 

17-52  0-514  0-12  0-016  0022    — 

Koderer      (carte 

1          1        1 

{ 

blanche) 

1-0572    9-50 '20-24  0-70  0-97 

0-26 

18-50  1-514  0-12'o-012  0-017    — 

Monopole  . 

1-0280    8-21 10-15  0-57  0-23 

— 

8-45  0-897  0-13  0-016  0-025  0-059 

1        1 

Nitrogen 

1          1          1 

Port  wine 

1-0081 16-69 

8-05  0-40  0-43 

0-027 

5-82    —    0-23  0-0310-023  0-102 

Sherry  . 

0-9932  17-45 

3-98  0-45  0-52 

0-027 

2-12    —    0-38  0-0310-128  0-206 

Madeira 

1-0003  15-40 

5-52  0-43  0-74 

0-020 

3-23    —    0-35  0-060  0-075  0-149 

Marsala 

1-0022  15-85 

1 

5-27  0-49  0-51 

1        ! 

0-037 

3-53    —    0-38,0-029  0-1140-142 

1          1          1 

There  are  other  constituents  of  these  wines  which  are  important,  but 
cannot  be  expressed  in  a  table  of  percentage  composition.  These  are 
chiefly  the  '  compound  ethers,'  which  give  the  'bouquet '  to  wine,  although 
this  is  also  partly  due  to  other  aromatic  bodies  present.  The  compound 
ethers  are  numerous,  and  consist  mostly  of  oenanthic  ether,  but  citric,  malic, 
tartaric,  acetic  ethers,  and  the  ethers  of  higher  members  of  the  fatty  acid 
series  are  also  present.  The  bouquet  of  wine  is  a  permanent  quality,  as  long 
as  the  wine  remains  sound ;  it  is,  however,  developed  by  keeping  for  a 
greater  or  less  length  of  time. 

The  colouring  matters  of  wine  are,  to  a  greater  or  less  extent,  deposited 
on  keeping,  the  wine  thus  becoming  lighter  in  colour.  All  wines  are  acid, 
and  this  acidity  is  due  to  free  tartaric  acid,  and  to  the  acid  tartarate  of 
potassium  (tartar)  ;  but  other  vegetable  acids  are  also  present.  Tannin, 
derived  from  the  stalks  and  skins  of  the  grape,  is  also  present,  rendering  new 
wine  astringent ;  it  is  deposited  on  keeping  the  wine,  entering  into  combina- 
tion with  some  of  the  organic  bodies  present. 

On  keeping  wines,  therefore,  the  chief  chemical  changes  that  occur  are 
the  deposition  of  some  tannin  and  colouring  matter,  the  loss  of  a  Uttle  alcohol 
and  volatile  acid. 

4,  Spirits  contain  the  largest  quantity  of  alcohol  of  all  alcoholic  beverages. 
They  are  made  by  distilling  fermented  grapes  (brandy),  fermented  molasses 
(rum),  fermented  malt  or  malt  and  grain  and  other  materials  (whisky).  The 
greater  part  of  the  whisky  is  distilled  in  '  pot-stills,'  in  which  the  fire  is 
directly  applied  to  the  still  containing  the  fermented  liquid.  '  Patent '  or 
*  silent '  spirits,  which  are  largely  used  for  blending  potable  spirits  and  for 
fortifying  wines,  are  made  by  exposing  a  subdi\'ided  stream  of  the  fermented 
liquid  to  steam. 

According  to  Bence  Jones  and  Hassall  (quoted  by  Parkes '),  gin  contains 
from  49  to  60  per  cent,  of  alcohol,  with  an  acidity  of  0-2  grain  tartaric  acid 
per  ounce,  and  1  per  cent,  of  sugar.     It  is  usually  made  by  adding  juniper 

'  0^).  cit.  p.  319.  As  sold,  however,  gin  may  be  35  per  cent,  under  proof,  containing 
usually  about  30  per  cent,  of  alcohol. 


FOOD 


483 


and  other  flavouring  and  sweetening  agentss  to  patent  spirits.  The  specific 
gravity  of  brandy  is  0-929  to  0-934  ;  of  gin,  0-980  to  0-944  ;  of  whisky,  0-915 
to  0-920 ;  and  of  rum  0-874  to  0-926. 

Percentage  Composition  of  Spirits 
In  100  cubic  centimetres  are  grammes — 


- 

Wuter 

Alcoliol      [      Extract 

Acid= acetic 

Salts 

Common  brandy 
Cognac        .... 
Whisky'      .... 
Kum             .... 

(34-90 
55-60 
47-80 
36-50 

35-1 
43-9 
52-2 
61-4 

0-385 
0-036 
1-975 

0-067 
0-027 

0-024 
0-060 

The  basis  of  spirits  is  ethylic  alcohol  mixed  with  water ;  but  they  also 
contain  alcohols  higher  in  the  series  than  ethylic  (classed  together  as 
*  fusel-oil ' ),  compound  ethers,  and  empyreumatic  bodies  produced  during  the 
process  of  distillation.  The  varying  proportions  of  these  '  bye-products ' 
give  spirits  their  individual  characters,  such  as  taste  and  aroma.  In  '  patent ' 
spirits  the  chief  higher  alcohol  present  is  propylic ;  in  spirits  made  from 
molasses  and  from  malt  and  grain,  amylic  and  butylic  alcohols  are  the  chief 
alcohols  present.  The  aroma  of  brandy  is  due  to  compound  ethers,  cenanthic, 
butyric,  &c.,  and  that  of  rum  to  butyric  ether.  One  of  the  chief  empyreu- 
matic bodies  in  '  pot-still '  whiskies  is  furfurol,  which  is  present  to  the 
amount  of  0-005  per  cent. 

When  spirits  are  kept  for  several  years  they  become  '  mellowed.'  The 
change  is  usually  considered  to  consist  in  a  diminution  of  the  higher  alcohols 
and  the  ethers ;  but  J.  Bell  has  shown  that  in  spirits  kept  in  bond  for  six 
years  there  is  practically  no  change  in  the  proportion  of  higher  alcohols 
and  ethers  present,  and  that  the  '  mellowing '  appears  to  be  due  to  the  em- 
pyreumatic bodies,  including  furfurol,  diminishing  in  quantity  and  altering  in 
quality  so  that  they  become  less  harmful.^ 

The  Physiological  Action  of  Alcohol  and  of  Alcoholic  Beverages 

The  physiological  action  of  alcohol,  that  is,  of  pure  ethylic  alcohol,  is  not 
precisely  the  same  as  that  of  the  alcoholic  beverages  which  are  in  ordinary 
use.  These  contain  other  bodies  besides  alcohol,  which  possess  a  physiological 
action  of  their  own,  and  one  v/hich  is  not  always  masked  by  the  presence  of 
ethylic  alcohol.   It  will  be  well,  therefore,  to  consider  the  action  of  alcohol  first. 

1.  Physiological  Action  of  Alcohol. — A  great  distinction  must  be  drawn 
between  the  effect  of  alcohol  taken  in  dietetic  doses,  and  the  effect  when 
taken  in  excess.  Although  this  is  no  doubt  true,  it  is,  however,  difficult  to 
lay  down  any  general  rules  as  to  what  excess  of  alcohol  really  means.  It 
does  not  mean  simply  that  alcohol  is  taken  until  it  produces  intoxication  : 
that  is  undoubtedly  excess.  But  there  are  many  individuals  in  whom  a 
moderate  amount  of  alcohol,  habitiially  taken,  produces  severe  pathological 
effects.  It  may  be  said  that  these  are  weakly,  although  apparently  healthy,  in- 
dividuals, and  that  this  is  a  question  more  of  medicine  than  of  normal  dietetics. 
It  is,  however,  a  fact  of  great  importance  to  bear  in  mind  in  discussing  the 
question  of  alcohol,  that  what  is  a  dietetic  dose  for  one  individual  may  pro- 
duce in  another  serious  effects,  if  the  habit  is  persisted  in. 

'  Whisky  is  usually  under  this  strength,  and  as  sold  may  be  14  to  30  under  proof. 
^  Eeport  on  British  and  Foreign  Spirits  by  a  Committee  of  the  House  of  Commons, 
1891. 

Ii2 


484  HYGIENE 

The  experiments  of  Austie,  of  Parkes  and  Count  Wollowacz  showed  that 
wdth  strong,  healthy  men,  '  accustomed  to  alcohol  in  moderation,'  the  amount 
of  alcohol  which  could  be  taken  daily  without  doing  harm  was  between  one 
and  two  ounces.  If  more  than  this  quantity  of  alcohol  were  taken  in  the 
day,  alcohol  was  detected  in  the  urine ;  a  sure  sign  that  too  much  had  been 
taken.  It  is  not  quite  accurate,  however,  to  apply  these  results  generally. 
As  has  been  noted  already,  owing  to  the  idiosyncrasy  of  alcohol,  one  ounce 
of  absolute  alcohol  daily  to  some  individuals  would  be  a  poison,  the  effect  of 
which  would  be  aggravated  if  the  amount  of  alcohol  were  translated  into 
terms  of  beer,  claret,  or  other  wines.  The  dietetic  dose  which  might  be 
taken  without  harm  by  the  majority  of  town  livers  is  probably  under  one 
ounce.  Parkes'  and  Wollowicz'  experiments  were  performed,  it  must  be 
recollected,  on  '  two  powerful,  healthy  men  accustomed  to  take  alcohol.' 

When  taken  into  the  stomach,  dietetic  doses  of  alcohol  increase  the 
vascularity  of  that  organ,  producing  a  sensation  of  warmth,  and  also  augment 
the  secretion  of  gastric  juice.  At  the  same  time  the  appetite  is  excited.  This 
is  no  doubt  the  explanation  of  the  taking  of  alcohol  before  meals  ;  a  custom, 
however,  strongly  to  be  deprecated,  since  the  form  of  alcohol  usually  taken  is 
concentrated  and  liable  to  produce  indigestion.  The  effect  of  alcohol  on  the 
chemical  process  of  digestion  has  already  been  discussed.  Koberts,  Bikfalvi, 
and  others  have  concluded  that  even  when  alcohol  is  present  in  the  digestive 
mixture  to  the  extent  of  10  per  cent,  it  has  no  appreciable  effect  on  the 
fermentative  changes  occurring.  It  is  otherwise,  however,  with  alcoholic 
beverages— beer,  wine,  &c.  (p.  475  et  seq.). 

When  taken  for  some  length  of  time  in  excess,  alcohol  causes  a  great  dis- 
turbance of  the  digestive  system.  It  causes  loss  of  appetite,  with  a  sense  of 
craving  for  alcoholic  drinks,  and  a  long  train  of  dyspeptic  symptoms.  Morning 
nausea  and  vomiting  also  appear,  due  to  the  fact  that  in  most  cases  the 
alcohol  is  largely  taken  in  the  evening,  and  the  stomach  remains  partly  full 
during  the  hours  of  sleep.  The  prolonged  use  of  alcohol  also  causes  the 
bowels  to  act  two,  three,  or  four  times  a  day,  and  this  is  a  common  symptom 
in  habitual  topers.  To  the  effect  of  alcohol  must  be  ascribed  some  cases  of 
severe  gastric  catarrh  and  the  degeneration  of  the  secretory  glands  of  the 
stomach  observed  by  Wilson  Fox.  After  being  absorbed  into  the  blood, 
alcohol,  according  to  Schmiedeberg,^  forms  a  compomad  with  h^emoglobm, 
which  more  readily  gives  off'  oxygen  than  haemoglobin  itself.  The  result  of 
this  is  that  alcohol  lessens  oxidation  in  the  blood  and  the  tissues.  Most  of 
the  alcohol  taken  is  oxidised  in  the  body,  the  products  being  excreted  in  the 
urine.  In  dietetic  doses,  some  of  the  alcohol  may  be  detected  in  the  expired 
air,  but  it  can  be  detected  in  the  urine  only  when  the  dose  is  excessive.  The 
presence  of  alcohol  in  the  urine  is,  therefore,  to  some  extent,  a  chemical  test 
of  an  excess  of  alcohol  having  been  taken. 

Alcohol  stimulates  the  heart,  producing  increased  force  and  rapidity  of  the 
cardiac  beat.  It  thus  tends  to  increase  the  blood-pressure  by  acting  on  the 
heart,  and  to  increase  the  flow  of  blood  from  the  arteries  into  the  veins. 
The  effect  on  the  blood-pressure  is,  however,  partly  counteracted  by  a  coin- 
cident dilatation  of  the  blood-vessels  of  the  skin,  which  thus  becomes  flushed, 
and  tends  to  produce  more  sensible  perspiration. 

It  is  a  question  whether  alcohol  sensibly  lowers  the  temperature  of  health, 
and  authorities  are  not  agreed  on  this  point.  There  is  no  doubt  that  in  some 
cases  of  fever  alcohol  does  lower  the  temperature,  especially  in  children  ;  and 
in  health  it  may  be  considered  to  tend  to  lower  the  body-temperature  in  two 
ways,  as  Dr.  Lauder  Brunton  points  out,  first,  when  given  in  medium  doses, 
'  Quoted  by  Brunton,  Pharmacology,  3rd  ed.  p.  767. 


FOOD  485 

by  dilating  the  cutaneous  vessels,  whereby  more  blood  comes  to  the  surface 
of  the  body,  and  thus  more  heat  is  lost  by  radiation  and  by  means  of  the  in- 
creased perspiration  ;  second,  when  given  in  large  doses,  by  lessening  the 
processes  of  oxidation  in  the  body.  But,  although  it  is  doubtful  whether 
alcohol  lowers  the  temperature  of  health,  there  is  no  doubt  whatever  that  it 
tends  to  lower  the  natural  resistance  of  the  body  against  cold.  When  an 
individual  is  exposed  to  intense  cold  for  a  long  period,  as  in  the  Arctic 
regions,  he  may  derive  some  temporary  comfort  and  sensation  of  warmth  from 
the  taking  of  alcohol ;  but  his  power  of  resistance  to  the  intense  cold  is  lessened, 
and  instances  have  been  recorded  where  death  has  occurred  under  such  con- 
ditions during  sleep. 

The  physiological  effects  of  alcohol  which  have  been  considered  are  quite 
subsidiary  to  its  effect  on  the  central  nervous  system,  as  there  is  no  doubt  that 
it  is  for  this  effect  on  the  brain  that  alcoholic  beverages  are  so  universally 
taken  by  mankind.  The  first  effect  that  alcohol  has  on  the  brain  is  that  of  a 
stimulant,  and  it  probably  acts  as  such  in  two  ways,  namely,  by  the  increasing 
the  circulation  of  blood  through  the  brain,  which  is  thus  roused  to  greater 
vigour,  and  by  directly  stimulating  the  nerve-cells  of  the  nerve-centres.  This 
stimulant  effect  is  observed  chiefly  after  medium  or  dietetic  doses,  and  its  result 
is  seen  in  many  individuals  by  an  increase  of  mental  and  bodily  activity,  and 
of  acuteness  of  perception  by  the  special  senses.  This  beneficial  physio- 
logical effect  is,  however,  soon  replaced  by  poisonous  symptoms  if  the  dietetic 
doses  are  too  often  repeated,  or  a  large  quantity  of  alcohol  is  taken  at  once. 
For  alcohol  then  becomes  a  depressant  and  paralyser  of  the  central  nervous 
system,  and  symptoms  of  intoxication  appear.  This  depressant  effect  is,  as 
Brunton  points  out,  one  of  progressive  paralysis.  The  higher  centres  of  the 
brain  are  first  affected,  then  the  lower.  The  perceptive  centres  are  paralysed, 
so  that  correct  judgment  is  no  longer  possible,  while  the  emotions  are  uncon- 
trolled and  thrown  out  of  working  gear,  fits  of  boisterous  hilarity  and  of 
emotional  depression  being  common  symptoms.  Speech  becomes  disordered, 
and  symptoms  of  inco-ordination,  due  probably  to  an  effect  on  the  cerebellum, 
appear.  The  respiratory  centre  in  the  medulla  then  becomes  affected,  and 
at  this  stage  there  is  coma  with  stertorous  breathing,  while  the  action  of 
the  heart  still  continues,  even  after  respiration  has  stopped. 

There  can  be  no  question  that  alcohol  taken  in  sufficient  quantities  tc 
depress  the  higher  centres  of  the  brain-  does  an  infinite  amount  of  harm. 
The  only  question  regarding  the  use  of  alcohol  is  whether  when  taken  in 
quantities  sufficient  to  produce  its  stimulant  effect  on  the  brain  it  is  beneficial 
or  not. 

The  serious  symptoms  and  pathological  changes  produced  by  the  use  of 
alcohol  in  excess  may  be  summarised  as  follows  : — 

It  delays  digestion,  causes  catarrh  and  degeneration  of  the  stomach,  and 
produces  morning  vomiting,  looseness  of  the  bowels  ;  symptoms  referable  to 
the  alimentary  tract.  It  also  causes  congestion  of  the  liver,  audits  prolonged 
use  ends  in  fatty  degeneration  or  fibrosis  (cirrhosis)  of  that  organ,  with  its 
attendant  serious  results.  It  seems  doubtful  whether  alcohol  can  of  itself 
produce  a  fibroid  condition  of  the  kidneys. 

Acute  alcoholic  poisoning  produces  coma  and  a  peculiar  form  of  delirium 
with  hallucinations  terrible  to  the  patient  (delirium  tremens),  while  to  chronic 
alcoholic  poisoning  may  be  ascribed  a  particular  palsy,  chiefly  affecting  the 
extremities  and  caused  by  a  peripheral  neuritis. 

The  abuse  of  alcohol  also  lessens  the  resistive  power  to  disease,  especially 
acute  disease  ;  and  such  individuals  die  rapidly  when  affected  with  pneu- 
monia and  other  acute  affections. 


486 


HYGIENE 


2.  Physiological  Action  of  Alcoholic  Beverages. — The  physiological  effect 
of  beer,  N^nes,  spirits,  &c.,  partly  depends  on  the  amount  of  alcohol  they  con- 
tain, and  partly  on  other  ingredients  which  have  a  physiological  action  of 
their  own. 

It  is  not  always  possible  to  say  what  these  ingredients  are  chemically ; 
but  there  are  some  facts  which  are  known  and  which  are  important.  The 
retarding  effect  of  beers  and  wines  on  the  chemical  processes  of  digestion 
has  already  been  considered  at  length,  and  the  cause,  as  far  as  is  known,  of 
this  retarding  effect.  It  is  now  necessary  to  consider  the  other  effect  of 
these  alcoholic  beverages,  as  such. 

Many  alcoholic  drinks,  especially  potent  spirits,  owe  their  deleterious 
effect  to  what  may  vaguely  be  described  as  '  impurities.'  Some  of  these 
impurities  consist  of  alcohols  higher  in  the  series  than  ethylic  (see  p.  488). 
Dujardin-Beaumetz  and  Audige  have  fomid  experimentally  that  such  alco- 
holic drinks,  with  impurities,  are  more  poisonous  when  given  to  animals  than 
the  pm-ified  spirits.  The  following  table '  of  the  results  of  these  observers 
shows  these  results.  Bad  brandy,  it  will  be  seen,  is  more  poisonous  than 
absolute  alcohol  in  the  proportion  of  5'8  to  7"75.  The  smaller  the  poisonous 
dose,  the  more  deleterious  the  alcoholic  beverage  will  be  when  drunk. 

Poisonous  Actiofi  of  Different  Kinds  of  Alcoholic  Prrparations 


Average  poisonous  do?e  per  kilogramme  of  body-        | 

End  of  alcohol 

weight  of   the  dog,  necessary 
death  in  24-36  hours 

to    produce 

Spirits  and  brandies 

Crude 

Rectified 

Grammes 

Grammes 

Grammes 

Ethylic  alcohol    ..... 

7-75 

— 

— 

Spirit  of  wine  of  Montpellier 

7-50 

— 

— 

„            „       from  pears     . 

7-35 

— 

— 

„            „       from    cider    and    from 

'•           marc  of  grapes      .... 

7-30 

— 

— 

SiDirit  from  grain          .... 

— 

6-96 

7-25 

,,          molasses  and  beetroot 

— 

6-90 

7-15 

Brandy  from  a  public-house  (ordinary 

quahty)          

7-00 

— 

— 

Brandy  from  a  public-house  (inferior 

_  ciuality) 

5-30 

— 

— 

Spirit  from  potatoes    .... 

— 

6-85 

710 

„              „       (said  to  have  been 

ten  times  rectified) 

— 

— 

7-35 

Some  of  the  undoubtedly  deleterious  effects  of  crude  spirits  must  be  as- 
cribed to  the  presence  of  furfurol  and  other  empyreumatic  bodies,  which 
diminish  and  alter  on  keeping  the  spirit.  These  substances  tend  to  derange 
digestion  and  appear  to  have  a  profound  effect  on  the  nervous  system. 

Beer  has  an  action  of  its  own,  probably  dependent  on  the  active  prin- 
ciple (lupulin)  of  the  hops  used  in  its  manufacture.  Lupulin  is  a  depressant 
to  the  nervous  system.  To  many  individuals,  beer  in  small  doses  acts  as  a 
soporific,  and  in  excess  it  has  a  well-marked  depressant  action.  This  depres- 
sion is  probably  due  to  the  lupulin,  and  not  to  the  potassium  salts,  as  con- 
sidered by  Eanke.  Taken  for  prolonged  periods,  beer,  even  in  dietetic  doses, 
seems  to  lead  to  the  deposition  of  fat  in  the  body,  and  it  probably  produces 

'  Taken  from  Brunton's  Pharmacology,  3rd  ed.  p.  771.  See  original  paper  of  Dujardin- 
Beaumetz  and  Audige  in  Comptes  Bendus,  vol.  Ixxxi.  pp.  192-194. 


FOOD  487 

ihis  result  by  lessening  oxidation  and  tissue  metabolism  in  the  body.^  Taken 
in  excess  for  long  periods,  beer  is  a  '  gout-producer,'  and  one  of  the  most 
potent  dietetic  agents  in  the  causation  of  that  disease. 

In  wines,  both  light  and  sweet,  the  constituents,  besides  alcohol, 
which  are  of  importance  are  the  vegetable  acids  and  the  compound  ethers. 
Beer  also  contains  vegetable  acids  and  their  salts,  and  spirits  contain  com- 
pound ethers  ;  while  in  all  these  are  mineral  salts,  which  are  of  service  in 
the  economy.  In  beer  and  the  sweet  wines  there  is  also  a  certain  amount 
of  carbohydrate  foodstuffs  in  the  form  of  sugar  and  dextrine.  According  to  the 
amount  of  carbohydrate  present,  these  alcoholic  beverages,  therefore,  supply 
valuable  food  to  the  organisms  ;  but  not  in  an  admixture,  it  must  be  re- 
membered, in  which  it  is  necessary,  or  convenient,  for  the  organism  to  assimi- 
late it. 

The  vegetable  acids,  however,  especially  in  Hght  wines,  undoubtedly  play 
an  important  role;  since  they  make  the  wines  antiscorbutic.  The  compound 
ethers,  besides  aiding  in  giving  the  bouquet  to  wines  and  spirits,  act  on  the 
central  nervous  system  as  sedatives,  and  when  taken  in  excess,  as  depress- 
ants. An  effect  has  been  ascribed  to  them  of  stimulating  the  secretion  of 
pancreatic  juice,  and  in  this  way  wines  and  spirits  containing  them  would  be 
of  aid  in  digestion.  It  is  true  that  Claude  Bernard  showed  that  sulphuric 
ether  acted  in  this  way ;  but  no  facts  are  as  yet  forthcoming  to  show  that 
the  compound  ethers  present  in  alcoholic  beverages  possess  this  beneficial 
.action. 

The  Dietetic  Use  of  Alcohol 

Alcohol,  it  is  often  said,  is  no  necessity  to  the  healthy  individual.  But 
no  hard-and-fast  rule  can  be  laid  down  on  the  subject.  We  have  to  take 
into  consideration  the  surrounding  physical  conditions  of  the  individual,  the 
poverty  or  ease,  the  hard  mental  or  bodily  labour,  all  of  which  conditions 
may  surround  healthy  individuals.  We  have  also  to  take  into  consideration 
the  colossal  fact  of  the  almost  universal  use  of  alcohol  among  nations,  more 
perhaps  among  civilised  than  among  savage  races. 

To  some  individuals,  alcohol  in  every  shape  or  form  is  a  poison,  not 
necessarily  producing  intoxication,  but  causing  in  course  of  time  bodily 
degeneration,  with  an  increase  of  fatty  and  fibroid  tissue  in  different  parts 
•  of  the  body. 

It  has  already  been  pointed  out  what  effects  alcoholic  beverages  taken  in 
dietetic  doses  have  on  the  chemical  processes  of  digestion  and  on  the  nervous 
system ;  effects  which  may  not  only  not  be  deleterious,  but  be  of  service  in  the 
conditions  of  life  under  which  we  live.  Thus  even  the  retardation  of  diges- 
tion may  be  of  benefit  in  aiding  the  complete  assimilation  of  a  large  meal ; 
and  the  stimulant  action  on  the  nervous  system  may  restore  the  nervous 
system  to  a  healthy  condition.  This  last  action,  indeed,  may,  in  many  cases, 
be  considered  more  as  a  question  of  therapeutics  than  of  dietetics  ;  for  the 
condition  of  nervous  system  produced  by  over-work,  in  which  alcohol  in 
small  doses  with  meals  is  often  beneficial,  is  a  pathological  and  not  a  physio- 
logical one. 

There  is  no  cogent  evidence  to  show  that  alcohol  is  of  service  in  increasing 
bodily  activity.  The  evidence  adduced  by  competent  observers  is  distinctly 
against  the  use  of  spirits  by  soldiers  in  time  of  war.  And  when  bodily  exer- 
tion has  to  be  combined  with  judgment  in  directing  one's  action,  alcohol,  by 

'  The  amount  of  carbohydrates  present  in  beer  does  not  account  for  the  deposition 
of  fat. 


488  HYGIENE 

blunting  the  judgment,  may  do  great  harm.  There  is  no  doubt,  however^ 
that  alcohol  is  of  ser\'ice  in  conditions  where  there  is  deficiency  of  food ;  for 
it  enables,  for  a  short  period  it  is  true,  bodily  vigour  to  be  maintained  on  an. 
insufficient  diet. 

11.  Beverages  containing  Alkaloids 

Tea,  cofifee,  Paraguay  tea,  guarana,  and  cocoa  come  under  this  head.  The 
first  four  have  as  their  active  principle  the  alkaloid  theine  or  caffeine  ;  cocoa 
contains  theobromine,  and  the  effect  of  these  beverages  in  their  dietetic  use 
is  chiefly  due  to  these  alkaloidal  principles. 

Caffeine  or  theine  is  chemically  trimethylxanthine  or  methyltheobro- 
mine,  C8H,oN40o.  Theine,  the  alkaloid  from  tea,  is  considered  as  identical 
with  caffeine,  and  is  commercially  sold  as  caffeine.  It  is  not,  however,  accord- 
ing to  May,  quite  identical  with  caffeine  in  its  physiological  action.  Caffeine 
exists  in  coffee  beans  in  about  0'5  to  1'24  per  cent.,  in  tea  from  2  to  4  per  cent., 
and  in  guarana  about  5  per  cent.,  and  in  Paraguay  tea  in  from  0'48  to  1"85 
per  cent. 

In  its  physiological  action,  it  plays  the  o'ole  of  a  cerebral  stimulant,, 
exciting  (but  not  necessarily  over-exciting)  the  brain  to  continued  activity 
and  stimulating  muscular  activity.  Both  coffee  and  tea  have  these  physio- 
logical effects.  Caffeine,  moreover,  stimulates  respiration  and  increases  the- 
blood-pressure  ;  but  in  its  further  effects  (as  from  an  overdose)  it  makes  the 
pulse  more  frequent  and  in  some  cases  intermittent.  Caff'eme  is  also  a 
diuretic.  Both  tea  and  coffee  may  also  have  this  action  on  the  pulse  and 
urine.  The  good  effects  of  tea  and  coffee  are  evident  from  what  has  been 
said  ;  they  stimulate  the  brain  and  restore  muscular  activity. 

Their  evil  effects  are  partly  seen  in  symptoms  of  disorder  of  the  digestive 
tract  and  partly  in  those  of  a  disordered  nervous  system.  Thus  tea  and 
coffee  indulged  in  to  excess  produce  dyspepsia,  chiefly  of  the  acid  form. 
Their  effect  in  delaying  the  chemical  processes  of  digestion  has  already  been 
discussed  (p.  474  et  seq.).  The  disordered  digestion  arising  from  the  abuse  of  tea 
and  coffee  has  been  ascribed  to  the  tannin  present  in  the  infusion.  There  is,, 
however,  no  e\ddence  of  this.  It  is  not  the  tannin  that  delays  the  digestion,, 
as  Roberts  has  shown;  and  most  of  the  symptoms  of  tea  and  coffee  abuse 
are  those  of  delay  of  digestion,  i.e.  of  food  remaining  undigested  in  the 
stomach.  Caffeine  is  itself  a  gastro-intestinal  irritant,  and  coffee  in  some 
individuals  produces  diarrhoea.  It  is  not,  however,  clear  what  constituent 
of  tea  and  coffee  is  the  active  agent  in  producing  dyspepsia. 

On  the  side  of  the  nervous  system  coffee  and  tea  may  lead  to  sleeplessness 
and  restlessness ;  in  some  people  such  symptoms  are  noticed  even  if  the 
beverages  are  not  taken  to  excess.  Tea,  moreover,  may  produce  muscular 
tremor. 

Some  eff'ect  must  be  ascribed  to  the  aromatic  principles  present  in  tea  and 
coffee  ;  these  no  doubt  greatly  add  to  their  consumption  or  have  the  same 
physiological  effect  as  the  aromatic  principles  already  discussed  (p.  474). 

Theohromine,  the  active  principle  of  cocoa,  is  closely  related  to  caffeine ; 
it  is  dimethylxanthine,  C7H8N4O2.  Only  traces  of  caffeine  are  found  in 
cocoa. 

The  physiological  action  of  theobromine  is  chiefly  exerted  on  the  muscular 
system ;  it  is  a  greater  restorer  of  muscular  activity.  Its  effect  on  the  nervous 
system  is  not  well  defined. 

Cocoa  in  infusion  has  but  Httle  physiological  action,  owing  to  the  small 
amount  of  theobromine  present.  In  its  raw  state,  cocoa  is  largely  composed, 
of  fat  and  to  a  less  extent  of  carbohydrates ;  and  even  in  the  '  prepared ' 


FOOD  480 

cocoas,  fat  is  present  in  large  amount.     Cocoa  must  therefore  be  considered 
as  a  fatty  food,  and  thus  differs  markedly  from  tea  and  coffee. 

Tea 

Tea  consists  of  the  dried  leaves  of  Camellia  thea.  It  is  grown  in  China^ 
India,  and  Ceylon,  and  from  these  countries  the  European  supply  is  derived. 
It  is  also  grown  in  Japan,  the  tea  produced  being  green  in  colour.  Black  tea 
is  the  form  usually  employed  in  Europe,  the  use  of  green  tea  having  greatly 
diminished.  Green  tea  contains  more  theine,  ethereal  oil,  and  tannin  than 
black  tea. 

The  tea  as  sold  consists  of  the  dried  leaves,  which  are  curled ;  they  may 
be  uncurled  by  placing  in  hot  water  and  unrolling,  and  then  placing  on  a 
slip  of  glass.  The  shape  is  ovate  and  pointed,  with  serrated  margin  almost 
to  the  stalks.     The  length  varies  somewhat.     In  all  teas  stalks  will  be  found. 

The  venation  of  the  leaves  is  characteristic.  The  large  veins  do  not  reach 
the  border  of  the  leaf,  but  turn  in  towards  the  mid-rib. 

Composition  of  Tea. — The  average  percentage  composition  of  black  tea  is 
9*51  of  water,  3*58  to  4*70  of  theine,  24*50  of  nitrogenous  substances,  0'68 
of  ethereal  oil,  6"39  of  fat,  wax,  chlorophyll,  and  resin,  6"44  of  gum, 
dextrine,  &c.,  15"65  of  tannin,  16"02  of  pectin,  11-58  of  cellulose,  and  5*65 
of  ash  (Geissler). 

"Wynter  Blyth  gives,  as  the  average  composition  of  black  tea,  6'44  per 
cent,  of  water,  1'43  of  theine,  35-61  of  '  extract,'  6-75  of  gum,  dextrine,  &c., 
and  6-72  of  salts,  of  which  3-29  are  soluble,  0*70  consists  of  silica,  and  1-44 
of  potassium.  The  salts  of  tea  consist,  besides  those  of  silicon  and  potassium, 
of  sodium,  magnesium,  iron,  and  manganese,  combined  with  phosphoric  acid, 
chlorine,  and  carbonic  acid. 

Infusio7i  of  Tea. — All  the  constituents  of  tea  are  not  soluble  in  hot 
water  ;  but  most  of  the  soluble  substances  are  dissolved  in  the  infusion  as 
made.  In  100  parts  of  tea  (air-dried),  33"64  parts  are  soluble  in  water,  con- 
sisting of  12-38  parts  of  nitrogenous  substances  (including  theine),  17*61 
parts  of  nitrogen-free  substances,  3-65  parts  of  salts,  of  which  2-10  parts 
consist  of  potassium  salts. ^ 

Tea  infused,  as  it  ought  to  be,  for  the  period  of  three  minutes  only,  does 
not  contain  so  large  a  proportion  of  soluble  matter. 

Adulterations  and  Examination  of  Tea. — Good  tea  consists  mostly  of 
whole  leaves  of  the  characteristic  structure  previously  described.  Other 
leaves  containing  tannin  are  mixed  with  tea  as  adulterations ;  such  as  the 
willow,  oak,  sloe,  hawthorn,  elder,  beech,  and  (in  China)  the  Camellia 
sasanqua  and  Chloranthus  inconspicuus.  None  of  these,  except  the  sloe, 
willowfand  the  Camellia  sasanqua  and  Chloranthus  could  be  mistaken  for  tea 
leaves.  The  sloe  is  distinguished  by  its  obovate  shape  as  contrasted  with  the 
ovate,  acute  tea  leaf ;  the  willow  leaf  is  characterised  by  its  irregular  serration.^ 

Tea  is  sometimes  mixed  with  insoluble  matter,  such  as  catechu,  sand,  and 
magnetic  oxide  of  iron.  The  last  two  fall  to  the  bottom  of  an  infusion  and 
are  readily  detected. 

In  the  examination  of  tea,  an  infusion  ought  to  be  made  to  judge  of  the 
aroma  and  astringency.     The  aroma  is  slight  in  old  or  adulterated  tea. 

The  total  soluble  matters  are  estimated  by  infusing  a  weighed  quantity  with 
a  large  excess  of  distilled  water,  and  evaporated  to  dryness  on  a  water-bath, 

1  This  large  proportion  of  potassium  salts  in  the  infusion  may  account  for  part  of 
the  depression  following  the  abuse  of  tea. 

*  For  further  information  on  these  points  see  Hassall,  op.  cit. 


490  HYGIENE 

The  ash  ouglit  not  to  be  above  8  per  cent,  in  air- dried  tea  :  it  is  usually 
about  o"5  to  6  per  cent. 

Tlie  amount  of  tannin  may  be  estimated  by  infusing  a  weighed  quantity 
of  tea  and  precipitating  the  tannin  with  gelatine :  100  parts  of  the  dried 
precipitate  is  equal  to  40  parts  of  tannin.^ 

Coffee 

Coffee  is  obtained  from  the  seeds  of  Caff'ca  arabica,  obtained  from  various 
parts  of  the  tropics.  The  principal  varieties  are  Mocha,  Ceylon,  and  West 
Indian,  all  differing  somewhat  in  flavour. 

The  compositon  of  mn-oasted  coffee  beans  is  11-23  per  cent,  of  water, 
12'07  per  cent,  of  nitrogenous  substances,  1'21  per  cent,  of  caffeine,  12-27  per 
cent,  of  fat,  8-55  per  cent,  of  sugar  and  dextrine,  33-79  per  cent,  of  tannin  and 
other  nitrogen-free  bodies, ^  18-17  per  cent,  of  cellulose,  and  3-92  per  cent,  of 
salts,  which  consist  chiefly  of  potassium  and  phosphates.  This  is  the  average 
composition.  In  some  specimens  of  cofl'ee,  the  percentage  of  cafl'eine  is  higher, 
and  that  of  cellulose  may  be  from  27-5  to  34-4  percent. 

In  the  roasting  of  coffee,  the  caffeine  is  not  destroyed,  but  dissociated  from 
its  combination  with  the  tannin :  the  sugar  and  dextrine  are  changed  into 
caramel,  while  some  of  the  cellulose  is  charred,  and  gases  of  combustion  are 
given  off"  and  water  evaporated.  At  the  same  time  the  aroma  is  developed. 
The  average  composition  of  roasted  coffee  is  1*15  per  cent,  of  water,  13-98  per 
cent,  of  nitrogenous  substances,  1-24  per  cent,  of  caffeine,  14-48  per  cent,  of 
fat,  0-66  per  cent,  of  sugar,  45-09  per  cent,  of  other  nitrogen-free  bodies,  19-89 
per  cent,  of  cellulose  and  4*75  per  cent,  of  salts. 

Infusion  of  Boasted  Coffee. — For  the  making  of  good  coffee  (an  art 
practically  unknown  in  this  country)  the  berries  must  be  ff'eshly  roasted  and 
gi'ound.  The  percolator  used  must  be  warmed,  and  one  large  teaspoonful 
of  the  ground  coffee  for  each  breakfast-cupful  placed  in  it. 

A  sufficiency  of  boiling  water  must  then  be  added  and  allowed  to  flow 
through  ;  and  after  it  has  flowed  through,  it  must  be  returned  to  the  per- 
colator again  ;  twice  is,  as  a  rule,  sufiicient  to  obtain  a  good  infusion. 
Boiling  the  infusion  destroys  the  aroma.  One  hundred  parts  of  coffee  yield 
to  boiling  water  25-50  parts  of  soluble  matter,  consisting  of  3-12  parts  of 
nitrogenous  substances,  5-18  parts  of  oil,  13-14  parts  of  non-nitrogenous  sub- 
stances, and  4-06  parts  of  salts. 

The  physiological  action  of  coffee  and  of  its  active  principle,  caffeine, 
has  already  been  discussed  (p.  488). 

Adulterations  of  Coffee. — The  ground  coffee  is  adulterated  with  chicory 
and  with  several  starch -containing  grains,  the  cereals,  beans,  maize,  and 
potatoes,  and  with  sugar. 

The  composition  of  chicory  varies  greatly  from  that  of  coffee.  In  100 
parts,  there  are  in  roasted  chicory  13-16  parts  of  water,  6-63  of  nitrogenous 
substances,  2-74  parts  of  fat,  17-89  parts  of  sugar,  41-42  parts  of  other  non- 
nitrogenous  bodies,  12-07  parts  of  cellulose,  and  6-19  parts  of  salts.  The 
large  amount  of  sugar  in  roasted  chicory  as  compared  with  that  in  roasted 
coffee  (17-89  per  cent,  in  the  former  and  0-66  per  cent,  in  the  latter)  is  a 
point  of  distinction,  as  well  as  the  larger  proportion  of  salts  (6*19  and  4*75 
per  cent.) 

Chicory  may  also  be  distinguished  by  the  fact  that  the  roasted  beri'y  sinks 

'  For  the  process  for  the  separation  of  theine  see  Eichter's  Organic  Chemistry,  p.  349 
English  translation,  1886. 

-  The  proportion  of  tannin  is  about  5  per  cent. 


FOOD  491 

in  water,  while  the  freslily  roasted  coffee  berry  floats,  and  by  the  microscopical 
examination  which  shows  in  chicory  the  dotted  ducts.^  The  presence  of  any 
of  the  varieties  of  starch  is  shown  by  the  blue  colour  given  to  a  dilute  infusion 
with  solution  of  iodine  and  by  a  microscopical  examination. 

Acorns  and  parsnip  roots  are  sometimes  used  to  adulterate  ground  coffee. 

Paraguay  Tea —  Guarana 

Paraguay  tea  {mate)  is  obtained  by  roasting  the  leaves  of  Ilex  para- 
guayensis  and  exposing  them  to  the  action  of  the  sun.  It  is  used  in 
Paraguay  and  other  parts  of  South  America.  It  contains  3-87  per  cent, 
of  proteids,  0-48  per  cent,  of  theine  (1*48,  according  to  Byasson),  2  to 
4-5  per  cent,  of  fat,  resin,  and  chlorophyll,  2-38  per  cent,  of  sugar,  4-1  per 
cent,  of  tannin,  and  3'92  per  cent,  of  salts :  24  per  cent,  of  the  solids  is 
soluble  in  water. 

In  infusion,  it  has  an  action  similar  to  other  caffeine-containing  beverages, 
but  is  more  apt,  it  is  said,  to  cause  digestive  disturbance. 

Guarana  is  obtained  by  roasting  the  seeds  of  Patdlinia  sorbilis.  It  con- 
tains a  large  proportion  of  caffeine,  5  per  cent.  It  has  been  used  in  migraine 
with  some  success. 

Cocoa 

Cocoa  is  prepared  from  the  seeds  of  the  Theohroma  cacao.  Cocoa  beans 
consist  of  7'11  per  cent,  of  water,  0*45  per  cent  of  theobromine,  51'78  per 
cent,  of  fat,  8"33  per  cent,  of  starch,  and  3*60  per  cent,  of  salts.  When  charred 
and  burnt,  some  of  the  starch  becomes  changed  into  dextrine  and  sugar.  The 
beans  then  have  the  following  composition :  5'58  per  cent,  of  water,  14*13 
per  cent,  of  nitrogenous  substances,  1'55  per  cent,  of  theobromine,  60'09  per 
cent,  of  fat,  8"77  per  cent,  of  starch,  13"91  per  cent,  of  other  nitrogen-free 
bodies,  3*93  per  cent,  of  cellulose,  and  3*45  per  cent,  of  salts. 

The  cocoa  found  in  commerce  is  '  prepared : '  a  part  of  the  fat  is  removed, 
and  in  most  cases  starch  and  sugar  are  added.  An  average  composition  of 
such  preparations  is  the  following  : — 6*35  per  cent,  of  water,  21'50  per  cent,  of 
nitrogenous  substances,  chiefly  proteid,,  1*82  per  cent,  of  theobromine,  27'34 
per  cent.,  of  fat,  2'53  per  cent,  of  sugar,  15'17  per  cent,  of  starch,  16*48  per 
cent,  of  the  non-nitrogenous  bodies,  6*44  per  cent,  of  cellulose,  and  5'19 
per  cent,  of  salts. 

Cocoa  is,  therefore,  a  fatty  and  a  proteid  food,  and  to  some  extent  a  carbo- 
hydrate food  also.  It  has  but  little  stimulant  action,  but  the  small  amount 
of  theobromine  present  no  doubt  acts  as  a  restorer  of  muscular  activity.  The 
cocoa  of  commerce  is  largely  adulterated  with  the  different  starches  of  the 
cereals,  potato,  arrowroot,  &c.,  the  presence  of  which  is  readily  detected  by 
the  microscope.  Sugar  is  also  added.  Mineral  adulterations  are  detected  by 
chemical  tests. 

^  Fox  further  information  on  this  point  see  Hassall,  op.  cit. 


THE  mSPECTION  OE  MEAT 

BY 

E.  W.  HOPE,  M.D.,  D.Sc. 

.ASSISTAin;  MEDICAl  OFFICER  OF  HEALTH 
IBCT-UBBK  ON  PUBLIC  HEALTH,  UNIVERSITY  COLLESB,  LIVERPOOI. 


THE   INSPECTION   OF   MEAT 

The  Legislature  imposes  important  duties  and  powers  upon  the  duly  ap- 
pointed officials  of  sanitary  authorities  in  respect  to  the  examination  of 
meat.  The  Acts  in  which  these  duties  and  powers  are  defined  are  sections 
116,  117,  118,  and  119  of  the  Public  Health  Act  and  the  Sale  of  Pood  and 
Drugs  Act.  In  the  great  majority  of  instances  action  is  taken  under  the 
first-named  Act,  but  occasions  sometimes  arise  when  it  becomes  necessary  to 
proceed  under  the  latter  Act :  for  example,  in  the  fraudulent  substitution  of 
the  flesh  of  one  animal  for  that  of  another.^  Section  6  of  the  Sale  of  Food 
and  Drugs  Act  provides  that  '  no  person  shall  sell  to  the  prejudice  of  the 
purchaser  any  article  of  food  which  is  not  of  the  nature,  substance,  and 
quality  demanded  by  such  purchaser,  under  a  penalty  not  exceeding  twenty 
pounds.'  lit  is  important  to  bear  in  mind  that  in  proceeding  under  this  Act 
all  its  requirements  must  be  carefully  observed  :  the  article  must  hQ  purchased 
by  the  officer  or  his  agent,  and  must  be  submitted  to  the  analyst,^  whose 
certificate  specifying  the  result  of  the  analysis  must  be  produced  in  court  ; 
moreover,  the  person  purchasing  the  article  must,  on  the  completion  of  the 
purchase,  forthwith  notify  to  the  seller  his  intention  to  have  the  article 
analysed  by  the  public  analyst,  and  offer  to  divide  it  into  three  parts  to  be 
then  and  there  separated  and  sealed  up,  one  to  be  delivered  to  the  seller  (if 
he  so  wish),  one  to  be  given  to  the  analyst,  and  one  to  be  retained  for  future 
comparison.  A  person  refusing  to  sell  any  article  to  any  officer  is  liable  to  a 
penalty  of  101. 

The  ordinary  procedure  under  the  above-named  sections  of  the  Public 
Health  Act  is  different  from  the  foregoing.  Section  116  of  this  Act  directs 
that  *  any  medical  officer  of  health  or  inspector  of  nuisances  may  at  all  reason- 
able times  inspect  and  examine  any  animal,  carcase,  meat,  &c.,  exposed  for 
sale  or  deposited  in  any  place  for  the  purpose  of  sale,  or  of  preparation  for 
sale,  and  intended  for  the  food  of  man,  the  proof  that  the  same  was  not  ex- 
posed or  deposited  for  any  such  purpose,  or  was  not  intended  for  the  food  of 
man,  resting  with  the  party  charged ;  and  if  any  such  animal,  carcase,  meat, 
&c.,  appears  to  such  medical  officer  or  inspector  to  be  diseased,  or  unsound, 
or  unwholesome,  or  unfit  for  the  food  of  man,  he  may  seize  and  carry  away 
the  same  himself  or  by  an  assistant,  in  order  to  have  the  same  dealt  with  by 
a  justice.'  It  is  not  necessary  for  the  officer  to  give  notice  to  the  owner  of 
the  goods  seized,  but  it  is  customary  to  do  so  if  the  owner  can  be  found. 

Section  117  says  that  '  if  it  appears  to  the  justice  that  any  animal,  car- 
case, meat,  &c.,  so  seized  is  diseased,  or  unsound,  or  unwholesome,  or  unfit 
for  the  food  of  man,  he  shall  condemn  the  same,  and  order  it  to  be  destroyed 
or  so  disposed  of  as  to  prevent  it  from  being  exposed  for  sale  or  used  for  the 
food  of  man ;  and  the  person  to  whom  the  same  belongs  or  did  belong  at  the 

*  An  importer  of  large  quantities  of  tinned  meat  was  recently  convicted  and  fined  at 
the  Liverpool  Police  Court  for  selling  tins  labelled  '  Superior  Eoast  Mutton,'  vrhich  con- 
tained beef  with  mutton  fat  poured  over  it ;  the  difference  in  price  per  2-lb.  tin  between 
the  beef  and  mutton  was  threepence. 

'^  Omission  to  do  this  has  resulted  in  the  dismissal  of  a  summons. 


496  HYGIENE 

■time  of  exposure  for  sale,  or  in  wliose  possession  or  on  whose  premises  the 
same  was  found,  shall  be  liable  to  a  penalty  not  exceeding  201.  for  each 
j)iece,  or  at  the  discretion  of  the  justice,  without  the  infliction  of  a  fine,  to 
imprisonment  for  a  term  of  not  more  than  three  months.' 

It  is  a  question  whether  it  is  a  necessary  requirement  that  the  justice 
should  liimself  inspect  the  article  ;  in  some  places  this  is  done,  but  in  others 
the  justice  does  not  himself  inspect,  but  adjudicates  upon  these  cases  as  he 
does  upon  others,  viz.,  upon  the  evidence  brought  before  him.  The  late 
Mr.  Eaffles,  stipendiary  magistrate  of  the  City  of  Liverpool,  whose  experience 
was  probably  unique,  would  never  inspect  meat,  declining,  as  he  said,  to  act 
both  as  judge  and  witness.  Another  sound  reason  why  the  fitness  or  unfit- 
ness of  meat  for  food  should  be  decided  upon  the  evidence  of  those  practically 
acquainted  with  the  details  of  the  question,  rather  than  by  the  personal 
inspection  of  the  justice,  is  the  admitted  necessity  of  special  knowledge  to 
enable  a  correct  opinion  to  be  arrived  at  in  the  matter. 

By  section  118  of  the  same  Act  a  penalty  is  imposed  for  hindering  or 
obstructing  an  officer,  and  section  119  empowers  a  justice  to  grant  a  warrant 
to  an  officer  to  enter  any  premises,  to  search  the  same,  and  to  seize  any 
article  therein  which  he  may  deem  unsound,  unwholesome,  or  unfit  for  the 
food  of  man,  in  order  that  it  may  be  dealt  with  in  the  manner  described. 

Characteristics  of  Sound  Meat. — Good  meat  is  firm  and  elastic  to  the 
touch,  not  pitting  or  crackling  on  pressure  ;  juicy,  but  not  wet ;  the  fat,  when 
sufficient  time  has  elapsed  for  the  carcase  to  cool  and  set,  is  firm,  the  suet 
hard — containing  no  jelly  or  watery  juice — is  free  from  blood  stains,  and  in 
colour  varies  from  creamy  white  to  deep  yellow  ;  the  pleura  and  peritoneum 
are  free  from  adhesions  or  staining.  The  flesh  should  be  that  of  a  well- 
nourished  animal — not  attenuated ;  the  colour  should  be  uniform,  without 
brown  or  discoloured  patches.  Good  beef  is  of  a  bright  colour,  marbled  with 
fat ;  the  flesh  of  the  calf  is  always  paler  and  less  firm  to  the  touch  ;  mutton 
is  a  dullish  red,  firm,  the  fat  hard,  usually  white,  but  a  marked  yellowness  is 
consistent  with  wholesome  meat.  The  flesh  of  the  pig  is  pale,  and  less  firm 
to  the  touch ;  the  fat  also  is  soft ;  the  carcase  should  be  plump,  the  skin 
smooth,  not  setting  in  folds  or  wrinkles.  In  all  cases,  special  attention 
should  be  paid  to  the  connective  tissue  about  the  flanks  and  shoulders  and 
diaphragm,  and  below  the  fat  of  the  kidneys  ;  wetness,  oedema,  tubercle,  or 
other  evidences  of  disease  may  be  found  here  ;  the  thoracic  and  abdominal 
parietes  should  be  examined  for  evidence  of  stripping,  staining,  or  other 
abnormal  condition  ;  the  odour  of  the  carcase  should  be  sweet,  and  a  skewer 
plunged  into  the  flesh  should  have  no  unpleasant  smell  on  withdrawal. 

The  age  of  animals  is  important.  Young  animals  are  recognised  by  the 
condition  of  the  bones  and  their  cartilages  ;  with  advancing  age,  ossifica- 
tion becomes  more  complete,  the  bones  are  firmer  and  more  compact,  while 
the  cartilage  diminishes.  Newly-born,  or  still-born  calves  have  a  watery 
appearance  of  flesh  ;  the  fat  is  tallowy,  and  the  hoofs  are  yellow,  readily  in- 
dented with  the  nail,  and  show  that  the  animal  has  not  walked  on  them. 
In  old  animals  the  proportion  of  fat  to  lean  lessens  ;  bull-beef  is  firmer  and 
coarser  than  ox-beef,  darker  in  colour  and  less  juicy  ;  in  the  heifer  the  udder 
is  not  fully  developed,  and  contains  much  fatty  tissue  ;  in  the  old  cow  which 
has  had  several  calves  it  is  loose,  spongy,  and  brownish  in  colour ;  the  fat 
of  the  old  cow  is  deficient,  and  the  flesh  coarser  in  texture  and  darker  than 
that  of  the  heifer,  whilst  the  bones  are  completely  ossified. 

Wherever  possible,  the  viscera  should  be  examined,  and  a  knowledge  of 
human  pathological  processes  will  always  stand  the  medical  officer  in  good  stead ; 
when  examining  carcases  the  general  features  of  sound  meat  must  be  carefully 


THE  INSPECTION  OF  MEAT  497 

borne  in  mind,  and  due  weight  given  to  the  aggregate  deviations  from  thenormal 
standard.  It  may  be  laid  down  as  a  broad  general  rule,  that  in  all  chronic 
toasting  diseases  there  is  emaciation,  often  to  an  extreme  degree;  the  flesh 
is  pallid  in  appearance  and,  together  with  the  connective  tissue,  may  bo  infil- 
trated with  serum  ;  the  fat  and  visceral  connective  tissue  are  also  wet  and 
flabby,  and  the  fat  will  not  set ;  occasionally  the  pleura  is  found  to  have 
been  stripped  off  from  the  ribs  to  remove  evidence  of  pulmonary  disease. 
In  aciite  inflammatory  diseases  the  affected  organ  will  present  the  ordinary 
signs  of  inflammation,  but  if  the  animal  be  slaughtered  at  an  early  stage  ot 
the  disease,  and  is  properly  bled  and  dressed,  the  flesh  is  usually  normal  and 
sound  ;  if,  however,  the  animal  has  not  been  killed  until  when  moribund,  or 
if  the  disease  has  made  progress,  the  carcase  will  be  found  to  be  red  and 
congested  from  imperfect  bleeding  ;  it  will  not  set  properly,  and  the  flesh  will 
be  dark,  dry,  and  sticky,  and  frequently  giving  off  an  unwholesome  odour  of 
drugs  which  can  be  best  detected  by  plunging  a  skewer  deeply  into  the  flesh 
and  observing  the  smell. 

The  appearance  of  the  carcase  is  dependent  to  a  considerable  extent  upon 
the  manner  in  which  it  is  dressed ;  a  butcher  who  is  a  good  hand  at  his  trade, 
and  who  is  clean,  careful  and  prompt  in  killing  and  dressing  cattle,  will 
secure  a  better  wholesale  price  than  an  indifferent  man.  In  all  cases  the 
dressing  should  be  completely  finished  before  the  carcase  sets ;  on  no  account 
should  the  intestines  remain  in  longer  than  is  necessary.  In  dressing  cattle, 
when  the  animal  has  been  bled,  the  hide  is  partially  removed  from  the 
abdomen  and  hind  quarters,  and  the  animal  is  then  hauled  up  by  the  hind 
limbs  and  disembowelled;  the  hide  is  then  carefully  removed  from  the 
carcase,  so  as  to  leave  the  fat  on  the  back  as  smooth  as  possible.  The  carcase 
is  then  spht  with  saw  and  cleaver,  the  divided  brisket  being  bent  back  on 
either  side  and  secured  with  hooks  over  the  flat  ribs,  in  order  that  when  set 
the  part  shall  be  thicker  and  more  convenient  for  sale.  Care  is  taken  to 
keep  the  meat  clean,  in  order  to  lessen  or  prevent  the  necessity  for  washing. 

In  dressing  sheep,  the  skin  is  partially  removed  immediately  the  animal 
is  bled ;  the  carcase  is  then  suspended  by  the  hind  extremities,  disembowelled, 
and  the  skin  entirely  removed  ;  a  stick,  the  extremities  of  which  are  fixed  in 
the  abdominal  walls,  is  passed  across  the  back  of  the  animal,  so  as  to  expose 
the  inside  of  the  sheep.  The  fore-limbs  are  not  allowed  to  set  in  the  drooping 
position  they  naturally  assume,  but  are  fastened  up  with  skewers  so  as  to  set 
in  the  thickened  and  contracted  shape  most  convenient  for  sale,  and  which 
is  familiar  to  everyone. 

Lambs  are  treated  in  the  same  manner,  but  in  the  early  part  of  the 
season  the  skin  is  not  entirely  removed,  in  order  that  the  flesh  may  not 
become  dry ;  the  feet  also  are  left  on.  In  dressing  lambs,  a  piece  of  omental 
fat  is  spread  out  on  each  hind  quarter,  and  a  piece  of  mesenteric  fat,  carefully 
removed  from  the  intestines,  is  sold  with  each  fore-quarter. 

Calves  are  dressed  in  a  similar  fashion  to  lambs.  Pigs,  after  being  bled, 
are  scalded,  scraped,  and  disembowelled  in  the  manner  already  referred  to  ; 
they  set  with  a  smooth  and  plump  surface. 

All  ill-dressed  carcases  should  attract  attention,  since  diseased  animals,  or 
those  killed  when  moribund,  are  frequently  dressed  hurriedly  and  by  unskilled 
hands,  and  present  a  slovenly  appearance.  At  the  same  time,  it  must,  be 
mentioned  that  in  some  parts  of  the  kingdom  cattle  are  always  ill-dressed, 
frequently  packed  whilst  warm,  and  despatched  to  market ;  these  are  not 
attractive  in  appearance,  but  may  be  perfectly  sound. 

Befrigerated  Meat  is  imported  into  this  country  in  immense  quantities, 
and  usually  in  prime  condition,  and  it  keeps  well  on  exposure.     Beef  is  im- 

VOL.   I.  K  K 


498  HYGIENE 

ported  in  quarters,  wrapped  in  muslin  cloths  ;  the  fat  is  sometimes  stained 
with  the  meat  juice,  which  gives  it  a  dullish  red  appearance  ;  carcases  of 
sheep  are  imported  entire,  usually  wrapped  in  muslin  cloths.  When  com- 
mencing,' to  thaw,  both  beef  and  mutton  become  wet  on  the  surface,  and  if 
again  placed  in  the  refrigerator,  and  afterwards  again  thawed,  present  a  wet 
and  unsightly  appearance  which  must  not  be  confounded  with  oedema,  since 
the  flesh  is  sweet  and  good,  notwithstanding  its  appearance. 

Some  important  conditions  affecting  the  flesh  of  animals  used  for  food 
have  to  be  considered.  Among  parasitic  diseases,  the  most  important 
afi'ecting  the  sheep  is  occasioned  by  the  presence  in  the  liver  of  the  Distoma 
hepaticum,  coiiimonly  known  as  the  fluke.  The  parasite  in  question  is 
somewhat  sole-shaped,  about  i  uicli  to  1  inch  in  length,  and  is  found  in  the 
bile-ducts  in  very  varying  numbers.  A  few  of  these  creatures  may  be  met 
with  in  otherwise  perfectly  sound  sheep,  and  exercise  no  prejudicial  effect 
whatever  upon  the  flesh,  but  as  their  numbers  increase,  important  structural 
changes  take  place  from  pressure  and  obstruction  to  the  flow  of  bile  ;  jaundice 
and  dropsical  swellings  set  in,  together  with  diarrhoea  and  falling  oil'  of  the 
hair ;  emaciation  is  rapid,  and  so  extreme,  as  to  give  rise  to  the  common  name 
of  the  '  rot '  which  butchers  aj)ply  to  the  disease.  The  aflected  liver  should 
in  all  cases  be  destroyed,  and  the  carcase  should  be  condemned  if  it  be 
deteriorated.  The  disease  is  met  with  in  all  parts  of  the  country,  but  more 
especially  in  damp  and  wet  localities,  and  during  the  long-continued  preva- 
lence of  wet  weather  ;  the  eggs  and  the  embryo  are  developed  in.  water,  and 
hence  wet  seasons  are  conducive  to  the  spread  of  the  disease. 

Canurus  cerebralis,  the  cystic  form  of  the  Tcenia  ccenurus  of  the  dog,  is 
met  with  in  the  brain  of  the  sheep  and  ox,  producing  the  disease  known  as 
'  turnsick,'  '  sturdy,'  or  '  gid.'  In  the  early  stages  no  material  effect  is  pro- 
duced upon  the  flesh,  but  with  the  advance  of  cerebral  symptoms  the  animal 
emaciates,  the  flesh  deteriorates,  and  becomes  ultimately  in-nutritious  and 
valueless  as  an  article  of  food.  In  all  cases  the  parasite  should  be  de- 
stroyed. 

The  Strongylus  filaria  are  liable  to  be  met  with  in  the  lungs  of  the  sheep, 
and  ultimately  produce  wasting  of  the  tissues. 

Parasitic  animal  organisms,  by  which  the  human  being  may  be  attacked, 
are  of  great  importance.  Two  of  these  may  reach  him  through  the  medium 
of  the  flesh  of  the  pig. 

The  Tceniadoi  pass  through  two  distinct  phages  in  two  different  hosts  :  the 
encysted  state  of  the  Tcsnia  solium  of  man  constitutes  the  Cysticercus  celluloses 
which  commonly  affects  the  pig,  in  which  it  gives  rise  to  the  disease  known 
as  '  measles.'  The  '  measly  '  pork  contains  the  cysticerci  in  greater  or  less 
abundance,  lodged  chiefly  in  the  muscular  tissues,  voluntary  or  involuntary, 
also  in  the  liver,  brain,  connective  tissues,  and  serous  membranes  ;  they  are 
not  met  with  in  the  fat.  The  parasite  in  this  stage  consists  of  the  scolex 
and  its  cystic  surrounding ;  the  cyst  averages  the  size  of  a  pea,  and  is  em- 
bedded between  the  muscular  fibres,  from  which  it  can  be  readily  removed 
and  the  crown  of  booklets  demonstrated.  The  parasite  is  difficult  or  impos- 
sible to  detect  during  the  life  of  the  animal,  but  the  cysts  are  readily  visible 
as  soon  as  the  animal  is  killed  and  opened  ;  calcareous  degeneration  of  the 
cysts  sometimes  takes  place,  a  condition  which  is  readily  noticeable.  In  every 
case  of  this  affection,  the  carcase  of  the  animal  should  be  condemned  and 
destroyed  ;  it  is  both  prudent  and  desirable  to  treat  hams  and  bacon  in  which 
the  condition  may  be  found  in  a  similar  manner,  notwithstanding  that  the 
processes  of  curing  and  cooking  may  destroy  the  parasite. 

Trichina  spiralis  is  a  still  more  formidable  parasite,  and  gives  rise  to  the 


THE  INSPECTION  OF  MEAT  490 

disease  known  as  trichinosis.  The  parasite  attacks  other  animals  besides  the 
pig,  but  the  occurrence  of  trichinosis  in  man  is  usually  due  to  the  consump- 
tion of  the  flesh  of  an  infected  pig,  commonly,  it  is  believed,  in  an  imperfectly 
cooked  state.  The  trichina  are  small  thread-like  worms,  coiled  in  minute 
ovoid  cysts  within  the  muscular  fibres :  each  cyst  contains  one  immature 
trichina,  which  is  liberated  when  the  capsule  is  dissolved  by  the  processes  of 
digestion  ;  the  liber&ted  trichinre  develop  rapidly :  the  female  is  amazingly 
prolific,  ova  are  formed  and  impregnated,  and  the  young  find  their  way  into 
all  parts  of  the  body  of  the  host.  They  are  found  in  the  greatest  extent  in 
the  voluntary  muscles,  but  have  also  been  met  with  in  the  fat ;  the  diaphragm 
and  inter-costal  muscles  are  said  to  be  favourite  sites. 

Careful  examination  is  necessary  for  the  detection  of  the  trichinas  :  close 
inspection  reveals  a  speckled  appearance,  but  thin  sections  of  the  pork  should 
be  immersed  for  a  few  minutes  in  liquor  potassse,  until  the  muscle  becomes 
translucent,  washed,  and  afterwards  examined  with  a  lens  or  low  power  of 
the  microscope,  when  the  coiled-up  worm  will  be  seen  ;  the  cysts  are  occa- 
sionally gritty  from  the  presence  of  carbonate  of  calcium. 

All  the  flesh  of  an  infected  animal  should  be  destroyed. 

Dr.  Carsten  describes  as  follows  the  energetic  measures  adopted  in  the 
Netherlands  in  connection  with  an  outbreak  of  trichinosis,  and  which  resulted 
in  the  complete  extinction  of  the  disease  : — '  A  Eoyal  decree  was  issued  pro- 
hibiting the  removal  of  pigs  and  pig  manure  from  an  infected  district,  and  a 
special  veterinary  inspector  was  stationed  temporarily  in  the  neighbourhood 
as  supervisor  ;  the  local  authorities  instituted  a  strict  search  for  trichinae, 
ordering  that  all  pork  before  consumption  be  submitted  for  inspection  to  a 
competent  committee  appointed  for  that  purpose  ;  that  all  pig-yards  be  over- 
hauled, and  that  wherever  any  trace  of  trichinae  be  found,  the  infected  swine, 
and  all  vermin  found  in  the  neighbourhood  thereof  be  killed,  and,  together 
with  the  offal,  consumed  by  fire.'  *     These  measures  proved  quite  effectual. 

Tuberctdosis. — Cattle,  pigs,  poultry,  and  rarely  sheep,  are  all  liable  to  be 
affected  with  tubercle,  but  it  is  in  cattle,  and  more  especially  milk-cows,  that 
tuberculosis  is  met  with.  The  flesh  of  the  tuberculous  animal  is  affected  in 
varying  degrees,  and  much  diversity  of  opinion  exists  as  to  the  stage  at  which 
the  flesh  should  be  condemned.  Opinion  is  practically  unanimous  that  in 
advanced  stages  of  tuberculosis  the  consumption  of  the  flesh  should  be  pro- 
hibited, not  that  every  observer  is  prepared  to  state  that  its  consumption 
would  give  rise  to  specific  inoculation,  but  on  the  general  grounds  that  the 
flesh  is  so  deteriorated  as  to  possess  no  longer  the  nature,  quality,  and  pro- 
perties of  wholesome  nutritious  meat.  Thus  far  the  position  is  a  simple  one, 
and  any  practical  butcher  can  recognise  when  the  disease  has  advanced  so 
far  as  to  prejudice  the  quality  of  the  meat. 

Tuberculosis  is  known  by  various  names,  such  as  *  grapes,'  '  wasting,' 
'  pearls,'  and  the  like,  the  first  term  being  perhaps  the  commonest,  from  the 
fancied  grape-like  arrangement  of  the  nodular  tuberculous  masses  frequently 
found  adhering  to  the  chest-walls.  The  most  common  seats  of  the  disease 
are  the  lungs,  pleurae,  and  other  serous  membranes  ;  the  liver,  lymphatic,  and 
other  glands  are  often  affected,  sometimes  the  marrow  and  the  nervous 
system,  and  it  is  also  alleged  that  bacilli  have  been  found  in  the  flesh.  The 
extent  of  the  local  lesions  varies  widely ;  they  may  be  limited  to  a  single 
nodule,  or  almost  the  entire  organs  mentioned  may  be  invaded,  their  tissues 
destroyed  by  caseous  or  calcareous  masses  or  by  liquefying  pultaceous  matter. 
Grape-like  aggregations  of  various  sizes  attached  to  serous  membranes  are 

'  Communicated  to  the  Seventh  International  Congress  of  Hygiene  and  Demography. 

kk2 


iOO  HYGIENE 

■extremely  common,  and  the  condition  left  by  stripping  them  away  with  the 
costal  plem'ie  with  a  view  to  conceal  the  appearances  of  disease,  should  at 
once  attract  attention  and  lead  to  a  close  examination. 

The  various  conditions  are  all  forms  of  one  and  the  same  process,  and 
caused  by  a  microbe  which,  growing  in  the  tissues,  gives  rise  to  the  tubercles, 
and  which,  by  reason  of  its  being  thrown  otf  from  the  diseased  animal  in 
quantity,  renders  the  malady  a  contagious  one.  The  temperature  which  is 
most  favourable  to  the  growth  of  the  microbe  is  that  of  the  ordinary  body- 
heat  of  a  warm-blooded  animal,  say  98°  to  100°  Fahr.  A  temperature  of  or 
below  32°  Fahr.  appears  to  kill  it,  as  does  also  continued  exposure  above  108° 
Fahr.  These  are  points  of  considerable  practical  moment,  as  suggestive  of 
the  probable  effects  of  cooking  or  of  refrigeration  upon  the  bacillus.  It  is 
regarded  as  established  that  the  infectious  discharges  of  a  tubercular  animal 
remain  actively  virulent  in  this  climate  for  a  long  time  after  they  have  been 
cast  from  the  body,  and  stalls  and  sheds  may  thus  become  a  source  of  danger 
unless  thoroughly  cleansed.  Inhalation  appears  to  be  the  usual  way  in  which 
the  microbe  enters  the  body,  a  circumstance  which  would  be  anticipated  from 
the  frequency  with  which  the  lungs  are  the  seat  of  the  disease  ;  on  introduction 
into  the  blood,  the  disease  may  spread  so  rapidly  as  to  constitute  acute  or 
general  tuberculosis,  or,  on  the  other  hand,  it  may  be  limited  for  a  consider- 
able time  to  the  point  of  entry  and  neighbouring  lymphatic  glands,  which 
local  lesions  are  frequently  the  only  ones  detectable,  producing  during  life  no 
symptom  whatever,  the  animal  being  slaughtered  in  prime  condition. 

As  the  malady  progresses,  emaciation  and  weakness  become  marked,  milk 
diminishes  and  is  poor  in  quality  ;  when  the  animal  is  slaughtered  the 
extensive  signs  of  the  disease  already  described  are  met  with,  the  flesh  is 
soft,  skinny,  and  dropsical,  the  fat  wet  and  flabby,  the  carcase,  in  short,  pre- 
senting every  sign  of  unsound  meat. 

A  very  important  and  much  discussed  question  is  :  At  what  stage  is  the 
flesh  of  a  tubercular  animal  unfit  for  human  consumption  ?  Some  observers 
contend  that  the  whole  carcase  should  be  destroyed  if  the  merest  trace  of 
tubercle  is  discovered,  even  though  the  carcase  may  be  otherwise  in  prime 
condition.  The  general  practice,  however,  in  this  country  is  to  condemn  any 
carcase  in  which  the  disease  is  extensive,  or  has  progressed  so  far  as  to  cause 
deterioration  of  the  flesh.  In  Prussia,  where  very  great  care  is  taken  in 
inspecting  meat,  the  law  is  to  this  effect : — '  The  condition  of  the  flesh  of  a 
tubercular  animal  is  to  be  regarded  as  dangerous  to  health  when  the  meat 
contains  tubercular  nodules,  or  the  tubercular  animal  has  begun  to  show 
emaciation ;  while,  on  the  other  hand,  the  meat  is  to  be  regarded  as  fit  for 
food  when  the  masses  of  the  tubercle  only  occur  in  an  organ,  and  in  general 
the  beast  is  well  nourished.'  The  French  decree  says  :  '  The  flesh  of  tuber- 
culous animals  shall  be  excluded  from  consumption  (1)  if  the  lesions  are 
generahsed,  that  is  to  say,  not  confined  ;  (2)  if  the  lesions,  although  locahsed, 
have  invaded  the  greater  part  of  an  organ,  or  constitute  an  eruption  on  the 
walls  of  the  chest  or  the  abdominal  cavity.' 

That  the  tubercle  bacillus  may  be  introduced  into  the  body  by  swallow- 
ing is  shown  by  the  fact  that  tubercular  secretions,  mucus,  saliva,  portions 
of  tubercles  from  diseased  tissues,  and  cultures  of  the  bacilli  have  been 
swallowed  by  various  animals,  and  some  of  these  animals  have  subsequently 
developed  the  disease.  It  will  be  noted  that  in  all  of  those  cases  the  presence 
of  the  bacilli  was  demonstrable  in  the  tissues  swallowed — the  most  diseased 
parts  were,  in  fact,  carefully  selected  for  the  experiments.  There  is  obviously 
a  vast  difference  between  eating  masses  of  tuberculous  matter,  and  eating 
the  properly  cooked  flesh  of  an  animal  which  is  sound  except  for  the  presence 


TEE  INSPECTION  OF  MEAT  501 

of,  say,  a  nodule  in  the  lung.  In  the  report  of  the  inquiry  of  the  Depart- 
mental Commission  appointed  by  the  Privy  Council  in  1888  to  inquire  into 
the  subject  of  tuberculosis,  no  case  of  tuberculosis  in  man  from  eating  the 
flesh  of  tubercular  animals  was  stated,  although  witnesses  were  fully  inter- 
rogated upon  this  point.  Professor  Bang,  of  Copenhagen,  thinks  that  experi- 
ments show  that  the  muscular  tissue  is  so  unfavourable  a  nidus  for  the 
tubercle  bacilli  that  they  do  not  multiply  in  it.  He  is  of  opinion  that  the 
seizure  of  the  meat  of  every  tuberculous  animal  is  too  severe  a  measure,  and 
where  the  lesion  is  localised  he  does  not  consider  that  the  consumption  of 
the  meat  is  attended  with  danger. 

Foot  mid  Mouth  Disease  is  common  amongst  cattle,  sheep,  and  pigs.  It 
is  characterised  by  rise  of  temperature  as  a  premonitory  symptom,  the  animal 
showing  by  sucking  its  lips  and  the  movements  of  its  tongue  that  the  mouth 
is  the  seat  of  suffering  ;  saliva  flows  freely  from  the  mouth.  On  examina- 
tion, vesicles,  or  their  bases  ulcerated  from  maceration  in  saliva,  are  found 
on  the  tongue  and  on  the  mucous  membrane  of  the  mouth.  The  animal  does 
not  refuse  food,  but  frequently  drops  it  instead  of  swallowing  it,  feeding 
being  evidently  attended  with  pain.  In  most  instances  the  feet  are  also 
affected,  blisters  forming  around  the  hoofs  ultimately  drying  into  scabs ; 
vesicles  also  frequently  form  upon  the  udders  of  milk  cows,  more  especially 
about  the  teats,  which  dry  after  a  time  into  scabs.  The  disease  is  very 
infectious,  but  as  a  rule  so  mild  in  its  course  as  to  interfere  but  slightly  if 
at  all  with  the  condition  of  the  flesh  of  animals  affected  by  it.  Occasionally 
in  chronic  cases,  or  when  the  infected  animals  have  been  exposed  to  wet 
or  neglect,  the  conditions  may  be  aggravated,  the  eruption  extending  into 
the  alimentary  canal,  and  the  flesh  becomes  proportionately  deteriorated, 
sometimes  to  an  extent  which  renders  it  unfit  for  food.  Under  ordinary 
circumstances  the  flesh  cannot  be  distinguished  from  that  of  perfectly 
healthy  animals,  and  there  is  no  reason  why  it  should  not  be  passed 
for  food ;  the  affected  parts,  however,  the  head,  feet,  and  udder,  should  be 
destroyed. 

Pleuro-pneumonia,  that  is,  contagious  pleuro-pneumonia  of  cattle,  is  a 
disease  of  great  importance.  The  commencement  of  an  attack  is  very 
insidious,  and  great  difficulty  may  be  experienced  in  determining  the  nature 
of  the  illness  at  the  outset.  The  temperature  soon  rises  to  104°  or  105°  Fahr., 
and  the  animal  refuses  food  ;  a  short  dry  cough  develops,  and  the  breath- 
ing becomes  laboured  and  painful.  Percussion  on  the  side  of  the  chest  may 
reveal  dulness,  and  pressure  may  cause  the  animal  to  shrink.  In  milk  cows 
the  secretion  of  milk  is  lessened  or  stopped.  Post  mortem  the  signs  of 
inflammation  of  the  lungs  and  pleura  are  met  with ;  the  pleural  surfaces  of  the 
lungs  and  thorax  are  thickened  and  roughened  with  deposited  lymph  ;  the 
lungs  in  the  early  stage  exhibit  commencing  solidification,  and  later,  marked 
hepatisation,  the  organ  being  to  a  more  or  less  extent  solid,  and  necessarily 
greatly  increased  in  weight ;  pleuritic  effusion  is  common.  The  extent  to 
which  the  carcase  is  prejudiced  in  respect  to  its  fitness  for  human  food,  will 
depend  upon  the  degree  to  which  the  disease  has  advanced  before  the  animal 
is  slaughtered.  In  the  early  stages  nothing  can  be  detected  in  the  carcase 
to  indicate  that  the  animal  had  serious  and  acute  illness  ;  the  flesh  is  perfectly 
normal  in  colour,  smell,  and  consistence,  and  is  firm  and  well-set ;  but  with 
the  advance  of  the  disease,  in  addition  to  wasting,  the  flesh  is  dark  and  dis- 
coloured, imperfectly  bled  and  badly  set,  moist,  and  the  connective  tissue 
sometimes  infiltrated  with  serum.  It  is  a  general  practice,  from  which  there 
is  no  reason  to  depart,  to  allow  carcases  of  animals  affected  with  pleuro- 
pneumonia to  pass  into  the  market,  provided  they  present  no  signs  of  disease, 


502  HYGIENE 

nor  departure  from  normal  conditions  ;  but  when  the  disease  has  advanced, 
and  the  consequences  already  alluded  to  are  present,  the  carcase  should  be 
condemned. 

The  legislature  provides  stringent  regulations  for  the  suppression  of 
pleuro-pneumonia ;  immediate  notification  to  the  local  authority  of  the 
existence  of  the  disease  is  required,  and  all  infected  animals,  as  well  as  all 
others  which  have  been  in  contact  with  those  infected,  are  slaughtered,  and 
compensation  is  paid  to  the  owners  in  these  cases.  The  infected  places 
must  be  subsequently  cleansed  and  disinfected  as  prescribed,  and  the  premises 
are  not  to  be  declared  free  from  infection  for  fifty-six  days  from  the  date  of 
the  cessation  therein  of  the  disease. 

Anthrax  and  Anthracic  Diseases. — Anthrax  occurs  in  cattle,  sheep, horses, 
and  sometimes  in  pigs  ;  the  disease  is  rapidly  fatal,  especially  so  in  cattle,  the 
first  sign  of  an  outbreak  of  anthrax  or  splenic  fever  being  often  the  discovery 
of  a  dead  animal,  which  but  a  few  hours  previously  had  been  in  apparent 
health.  The  disease  is  readily  inoculable  into  other  animals,  inoculative 
contagion  being  a  common  means  of  its  transmission.  Anthrax  is  of  im- 
portance both  on  account  of  the  devastation  sometimes  caused  by  it  amongst 
animals  which  furnish  food  for  man,  and  not  less  on  account  of  the  serious 
consequences  which  it  produces  in  the  human  subject.  The  Bacilhis 
avthracis,  found  mainly  in  the  blood  and  spleen  of  infected  animals,  is 
rod-shaped,  multiplying  by  division,  and  when  artificially  cultivated,  growing 
into  long  homogeneous-looking  filaments,  straight  or  twisted,  in  which  spores 
ultimately  make  their  appearance.  These  spores  become  free,  and  when 
artificially  cultivated,  or  injected  into  the  blood  of  a  rodent,  germinate  into  the 
characteristic  bacilli.  In  the  human  subject  anthrax  occurs  amongst  those 
engaged  in  handling  raw  hides,  and  also  as  '  woolsorters'  disease ;  '  the  usual 
mode  of  infection  in  these  cases  is  by  inhalation  of  spores  adhering  to  the 
wool  of  animals  dead  of  anthrax,  or  by  their  inoculation  into  abrasions  upon 
those  handling  hides.  In  all  cases,  in  animals  as  in  man,  the  blood-vessels 
of  all  organs  contain  the  bacilli,  and  extravasations  of  blood  are  frequent  in 
many  parts  of  the  body ;  the  liver,  kidneys,  and  spleen  are  congested,  the 
spleen  being  much  enlarged,  soft,  dark  in  colour,  and  sometimes  found  to  be 
ruptured;  this  condition  of  the  spleen  gives  rise  to  the  names  'splenic  fever' 
and  '  splenic  apoplexy  ;  '  the  lymphatic  and  mesenteric  glands  are  also  en- 
larged and  softened.  In  the  earliest  stage  of  disease,  the  fiesh  may  not  present 
marked  change,  but  the  local  lesions  rapidly  develop,  the  odour  of  the  tlesh 
is  of  a  peculiar  unwholesome  kind,  and  decomposition  sets  in  rapidly.  The 
flesh  should  be  destroyed.  Immediate  notice  of  the  existence  of  this  disease 
must  be  given  to  the  local  authority,  whose  duty  it  is  to  ensure  that  measures, 
including  cleansing  and  disinfection,  be  taken  to  pi-event  its  spread,  and  who 
must  order  the  disposal  of  the  mfected  carcases  by  burial  or  destruction. 
'  Black-quarter,'  '  black-leg,'  or  '  quarter-ill '  is  an  anthracoid  disease  w^hich 
is  characterised  by  hiemorrhagic  effusion  into  the  subcutaneous  or  inter- 
muscular tissues  of  one  or  both  of  the  anterior  or  posterior  extremities.  The 
disease  is  not  uncommon  amongst  cattle,  is  very  infectious,  and  usually  ends 
fatally  the  second  or  third  day  after  infection.  The  extravasations,  as  also 
the  abdominal  and  thoracic  viscera,  contain  characteristic  bacilli.  The  flesh 
of  an  infected  animal  should  not  be  consumed  even  if  slaughtered  in  the 
earliest  stage  of  illness  ;  if  the  disease  has  made  any  progress  the  carcase 
must  obviously  be  destroyed  ;  decomposition  is  rapid. 

'  Braxy '  is  a  term  applied  to  a  variety  of  conditions,  some  of  which  are 
allied  to  splenic  apoplexy  in  the  sheep,  others  result  from  various  chronic 
illnesses  and  the  mal-nutrition  caused  thereby.     '  Wet  braxy '  appears  to 


THE  INSPECTION  OF  MEAT  503 

include  various  dropsical  conditions  irrespective  of  the  cause  which  gives 
rise  to  them  ;  under  the  term  '  red  braxy  '  appear  to  be  included  a  variety  of 
inflammatory  and  parturient  conditions  varying  greatly  in  importance  and 
resulting  generally  in  discolouration  of  the  flesh.  Errors  in  dieting  influence 
the  colour  of  the  flesh,  occasionally  giving  it  a  dark  or  bile-stained  appear- 
ance ;  but  this  condition  may  usually  be  distinguished  from  more  serious 
inflammatory  or  septicsemic  conditions  by  the  degree,  and  by  the  condition 
of  the  carcase  after  time  has  been  allowed  for  setting,  and  also  by  the  absence 
or  presence  of  local  lesions,  which  must  be  carefully  looked  for.  Under  no 
circumstances  should  the  flesh  of  an  animal  infected  with  anthrax  or  septi- 
caemia be  allowed  to  pass  into  the  market,  and  it  is  almost  unnecessary  to 
say  that  the  carcases  of  animals  dead  or  killed  when  dying  of  parturient  or 
other  inflammatory  diseases  should  also  be  excluded  ;  the  discoloured,  stained, 
unbled  carcase,  probably  in  an  incipient  stage  of  decomposition,  stands  self- 
condemned,  and  needs  no  expert  knowledge  to  condemn  it. 

'  Joint-ill'  or  *■  joint  felon '  are  names  applied  to  acute  rheumatism  with 
exudation  into  the  joints,  and  also  to  a  septic  condition  in  very  young 
animals,  arising  from  septic  inflammation  of  the  navel,  which  gives  rise  to 
serous  or  purulent  accumulations  in  the  joints,  and  to  the  formation  of 
abscesses  in  the  neighbourhood  of  the  aftected  joints ;  the  carcases  of  animals 
so  affected  are  totally  unfit  for  human  food. 

Swine  i^et'er, called  also  'hog  cholera,'  'typhoid  fever  of  swine,'  'purples,' 
'  soldier,'  &c.,  is  a  very  fatal  disease  amongst  swine,  and  one  which  in  the 
later,  if  not  in  all  stages  renders  the  flesh  of  the  affected  animal  unfit  for 
consumption.  The  disease  is  readily  communicable,  and  once  it  obtains  a 
hold  amongst  a  herd  of  swine  the  spread  is  rapid  and  the  losses  consequently 
great.  Hence  the  stringency  of  the  Privy  Council  Orders  in  requiring  a 
notification  of  every  outbreak  of  the  disease  to  be  made  forthwith  to  the 
appropriate  authority,  and  empowering  the  local  authority  to  treat  the 
place  as  an  infected  place,  and  to  cause  any  affected  swine  to  be  slaughtered 
and  also  any  swine  which  may  have  been  in  the  same  sty  or  shed,  or  in 
contact  with  the  affected  animals.^ 

Unfortunately,  in  the  early  period  of  its  development,  the  disease  during 
life  is  very  difficult  of  detection,  the  animal  perhaps  feeding  less  readily,  and 
being  less  vigorous  than  usual,  but  in  no  other  way  showing  any  important 
departure  from  the  healthy  state.  In  the  varying  modes  of  its  development 
and  progress  it  shows  an  analogy  with  typhoid  fever  in  man.  Sooner  or 
later,  however,  more  marked  constitutional  symptoms  arise ;  refusal  of  food  ; 
rise  of  temperature  to  about  105°  Fahr.  ;  unsteady  gait ;  partial  paralysis  of 
one  or  both  hind  quarters  ;  diarrhoea,  the  evacuations  being  frequently  mixed 
with  blood  ;  red  patches  or  blotches  appear  on  the  skin,  and  frequently 
vesicles  which  dry  up,  forming  a  crust.  In  some  instances  extravasated 
patches  appear.  It  must  be  noted  that  swine  are  very  prone  to  redness  of 
the  skin,  which  therefore  must  not  be  looked  upon  as  pathognomonic ;  ex- 
posure, over-driving,  and  certain  articles  of  food,  may  all  induce  a  superficial 
redness  more  or  less  marked. 

Posi-morte77iexamination  shows  inflammationand  ulcerations  of  the  alimen- 
tary canal,  most  commonly  in  the  large  intestine  ;  the  ulcers  bear  a  resem- 
blance to  those  of  the  human  intestine  in  typhoid  fever  ;  occasionally  a 
diphtheritic  deposit  covers  considerable  tracts  of  the  mucous  membrane  of 
the  intestine.     Patches  of  congestion  or   consolidation    are  nearly  always 

'  The  local  authorities  are  empowered  to  pay  compensation  for  animals  so  slaughtered 
to  the  extent  of  half  the  value  (not  exceeding  forty  shillings)  of  a  diseased  pig,  and  fuU 
value  (not  to  exceed  41!.)  for  a  healthy  pig. 


C04  HYGIENE 

found  in  the  lungs,  and  tlie  liver,  lymphatics,  and  other  parts  are  frequently- 
congested  or  present  infiltrations  of  blood.  With  regard  to  the  carcase,  it 
must  be  noted  that  the  redness  of  the  skin,  when  it  exists  in  this  disease,  is 
apparent  after  scalding  and  scrapmg ;  the  redness  extends  through  the 
subcutaneous  fat  down  to  the  flesh.  As  the  disease  advances,  the  flesh 
becomes  emaciated  to  varying  degrees,  pale,  flaccid,  dropsical,  and  of  a 
peculiar  and  unwholesome  odour. 

Flesh  from  Animals  which  have  Died,  or  wJiich  have  been  Damaged  or 
Killed  hij  Accident. — The  carcases  of  animals  which  have  been  drowned  or 
smothered,  or  which  have  been  found  dead  from  other  causes,  are  dark  and 
discoloured  by  reason  of  not  having  been  bled;  the  thoracic,  and  more 
especially  the  abdominal  walls,  are  stained  from  contact  with  viscera,  the 
odour  is  ofl'ensive,  and  discolouration  from  incipient  decomposition,  which 
rapidly  advances,  adds  to  the  unsightliness  of  the  carcase.  Most  meat  of  this 
class  must  always  be  condemned.  Fractures,  wounds,  and  bruising,  the 
frequent  result  fi'om  animals  being  trampled  on  by  others,  owing  to  improper 
penning  in  transit,  may  cause  injuries  so  extensive  as  to  necessitate  imme- 
diate slaughter  ;  in  these  cases,  if  the  animal  be  properly  bled  and  dressed,  the 
undamaged  portions  are  normal  in  condition  and  may  be  passed,  the  damaged 
parts  only  being  condemned.  Cceteris  paribus,  in  these  animals,  as  in  those 
which  have  been  in  ill-health  from  any  cause,  decomposition  of  the  flesh 
appears  to  set  in  earlier  than  in  the  flesh  of  animals  slaughtered  in  prime 
condition.  It  is  also  said  that,  during  warm  weather.  Transatlantic  cattle 
slaughtered  at  depots  in  this  country  present  signs  of  decomposition  in  the 
neighbourhood  of  the  thigh  and  shoulder  soon  after  slaughter  ;  this  is 
attributed  to  the  fatigue  and  constant  movement  during  the  long  journey. 

Parturient  Animals. — Carcases  of  animals  which,  owing  to  abnormal  con- 
ditions, have  been  slaughtered  immediately  before,  during,  or  after  parturition, 
are  not  necessarily  to  be  condemned.  If  the  labour  have  been  prolonged, 
the  animal  exhausted,  and  bruising  and  evidences  of  extravasation  or  inflam- 
mation about  the  pelvic  outlet,  haunch,  and  thighs  be  present,  the  flesh  else- 
where being  pale  or  livid,  wet,  and  ill-set,  the  seizure  should  be  made.  If,, 
however,  the  casualty  be  one  such  as  hfemorrhage  or  mal-presentation,  and 
the  animal  be  slaughtered  and  promptly  bled  and  dressed,  the  flesh  may 
present  no  abnormal  characteristic  and  be  perfectly  fit  for  consumption. 

In  Milk-fever  the  stage  of  the  illness  will  influence  the  condition  of  the 
flesh  ;  it  should  not  be  passed  if  the  usual  signs  of  deterioration  are  present. 

Blown  Veal  and  Lamb. — The  practice — and  a  very  disgusting  one  it  is — 
exists  among  some  low-class  butchers  of  blowing  up,  with  the  breath,  the 
connective  tissue  of  veal  and  lamb,  and  thereby  giving  an  appearance  of 
plumpness  to  poor  meat :  the  fraud  is  completed  by  taking  melted  fat  into 
the  mouth  and  blowing  it  over  the  freshly  dressed  carcase.  The  practice  is 
an  ofi'ence  against  ordinary  bye-laws,  and  may  be  recognised  by  the  emphy- 
sematous condition  of  the  meat  which  has  been  subjected  to  it. 

Consequences  of  the  Ingestion  of  Unsound  Meat. — It  has  already  been 
pointed  out  that  specifically  harmful  consequences  do  not  necessarily  follow 
from  the  ingestion  of  in-nutritious  flesh.  Meat  from  emaciated  and  worn-out 
animals  is  condemned  on  the  sufficient  grounds  that  it  is  in-nutritious,  and 
in  consequence  has  not  the  qualities  which  the  consumer  requires.  But  in 
regard  to  the  consumption  of  flesh  which  is  decomposing,  or  which  is  taken 
from  animals  which  have  suffered  from  inflammatory  disease,  or  certain  para- 
sitic diseases,  the  consequences  are  very  difi'erent,  and  few  medical  men  have 
not  from  time  to  time  had  abundance  of  evidence  to  show  this  ;  moreover, 
cooking  cannot  be  relied  on  to  prevent  this  mischief.     Unsound  meat  is 


THE  INSPECTION   OF  MEAT  50.'> 

liable  to  give  rise  to  symptoms  of  gastro-intestinal  disturbance,  diarrhcea, 
vomiting,  colic,  followed  by  more  serious  symptoms  of  septic  poisoning, 
prostration,  pyrexia,  and  failure  of  the  heart's  action  ;  many  such  cases,  some 
resulting  fatally,  have  been  recorded.  Pies  of  beef  or  pork,  sausages,  and  the 
like  have  also  given  rise  to  these  conditions.  Dr.  Ballard  quotes  a  number 
of  cases  in  which  mischievous  or  fatal  results  have  followed  the  ingestion  of 
animal  food  ;  out  of  fourteen  such  instances,  pig-meat  of  one  kind  or  another 
occasioned  the  illness  in  no  less  than  nine,  veal  in  one,  beef  in  one,  the  kind  of 
meat  not  specified  in  two,  tinned  salmon  in  one.  An  explanation  is  suggested 
of  this  special  liability  of  pig-meat  to  produce  these  specific  maladies  :  of  all 
adult  flesh  meats  ordinarily  eaten,  pork,  under  the  process  of  cooking,  fur- 
nishes the  largest  proportion  of  gelatin ;  young  meats,  such  as  veal,  are  also 
largely  productive  of  gelatin,  and  gelatin  is  a  favourite  nutriment  of  morbific 
bacilli.  As  a  result  of  his  investigations  Dr.  Ballard  considers  that '  in  in- 
fected food  capable  of  producing  disease  on  being  eaten,  we  find  one  or  both 
of  two  things — a  living  microscopic  organism  and  an  organic  chemical  poison 
of  greater  or  less  virulence.  Of  these  two  things,  that  which  is  immediately 
operative  in  the  production  of  the  morbid  phenomena  is  the  chemical 
poison  which  is  apparently  of  a  basic  nature  and  a  product  of  the  processes  of 
bacterial  life.' 

'  Specifically  different  bacteria,  capable  of  producing  this  chemical  poison, 
may  through  its  agency  give  rise  in  the  human  system  and  in  animals  to 
clinical  phenomena  and  pathological  changes  in  the  organs  which  are  so 
similar  that  at  present  they  cannot  be  distinguished.' 

'  Given  the  bacterium  and  favourable  environment,  the  bacterium  may 
grow,  multiply,  and  produce  its  own  special  chemical  poison  from  the  material 
which  affords  it  nourishment  either  outside  the  body  or  within  it.' 

The  presence  or  absence  of  an  incubation  period  prior  to  the  manifes- 
tation of  toxic  symptoms  is  explained  by  Dr.  Ballard  as  evidence  of  the 
symptoms  being  due  either  to  the  operation  within  the  body  of  the  bacterium 
itself,  or  of  their  being  due  to  the  operation  of  the  chemical  poison  already 
prepared  in  the  food.  Where  merely  the  bacterium  is  introduced,  time 
is  required  for  its  growth  and  for  the  formation  of  its  poisonous  chemical 
product ;  when  the  chemical  poison  already  prepared  outside  the  body  is 
introduced,  its  operation  is  more  speedy. 

Not  only  is  thorough  cooking  of  importance  in  all  cases,  but  equally  so  is 
the  observance  of  absolute  cleanliness  in  every  stage  of  the  preparation  of  the 
food  for  the  table. 

It  must  not  be  forgotten  that  thorough  practical  training  is  requisite 
before  the  inspection  of  meat  can  be  satisfactorily  undertaken.  A  medical 
man,  or  a  veterinary  surgeon,  will  necessarily  have  as  a  basis  an  acquaintance 
with  pathological  processes,  and  any  practical  butcher  must  necessarily  have 
acquired  experience  of  a  useful  kind.  The  routine  work  of  meat  inspection 
is  in  many  towns  relegated  to  an  ordinary  sanitary  inspector,  who  is  instructed 
to  refer  in  matters  of  doubt  to  the  medical  officer  of  health.  In  many 
instances  this  inspector  has  had  no  special  training  whatever,  and  conse- 
quently the  value  of  his  services  is  small.  The  custom  in  vogue  in  Liverpool 
for  many  years  past  is  to  select  the  meat  inspectors  with  great  care  ;  they 
are  men  physically  fit,  of  unquestionable  character,  and  with  practical  ex- 
perience as  butchers  acquired  in  the  public  abattoirs,  and  are  reqmred  to  give 
proof  of  a  thorough  acquaintance  with  meat  of  all  classes  before  undertaking 
the  duties  of  inspector.  Men  of  this  class  must,  of  course,  receive  an  ade- 
quate wage  ;  the  work  discharged  by  them  is  of  great  importance,  and  the 
employment  of  untrained  and  incompetent  men  can  only  result  in  harm. 


CLOTHING 

BY 

CtEOEGE  VIVIAN  POOEE,  M.D.,  F.E.C.P. 

PHYSICIAN  TO  UNIVERSITY  COLLEGE  HOSPITAL 


CLOTHING 

Olothing  is  used  for  the  protection  and  adornment  of  the  body ;  and 
although  the  latter  object  may  be  looked  upon  as  subsidiary  and  unimportant, 
it  cannot  be  neglected  while  human  nature  is  what  it  is. 

Clothing  protects  the  body  against  cold  and  heat,  wind  and  rain,  and  to 
a  certain  extent  against  knocks  and  bruises  which  are  common  enough  in 
the  daily  life  of  most  of  us,  but  especially  of  the  working  classes.  Civilised 
man,  who  is  obliged  to  wear  artificial  clothing  from  his  cradle  upwards,  is  in 
this  respect  at  a  disadvantage  when  compared  with  the  lower  animals,  whose 
natural  clothing  of  fur,  or  wool,  or  hair,  or  feathers,  is  provided  for  them. 

The  power  which  man  has,  however,  of  changing  his  clothing  and  adapt- 
ing it  to  differences  of  season  and  climate  enables  him  to  dwell  in  any  part 
of  the  world,  and  his  conmiand  of  clothing  thus  gives  him,  so  to  say,  an 
extraordinary  power  of  acclimatisation. 

While  the  uses  of  clothing  are  undoubted,  it  has  certain  inseparable 
drawbacks,  the  chief  of  which  is  the  weight  which  it  obliges  us  to  carry ; 
and  this  fact,  as  well  as  the  form  of  our  garments,  must  to  a  certain  extent 
hamper  the  free  movement  of  the  body,  and  in  some  degree  interfere  with 
its  development.  It  is  during  infancy  and  early  life  that  attention  to  the 
hygiene  of  clothing  is  of  most  importance.  Clothing,  again,  harbours  dirt, 
and  dirt  is  a  great  cause  of  disease,  so  that  unless  we  pay  constant  attention 
to  the  cleansing  of  our  clothes,  skin  diseases,  parasitic  and  otherwise,  are 
sure  to  result. 

A  treatise  on  clothing  must  necessarily  be  adapted  to  the  climate  and 
habits  of  the  people  for  whom  it  is  written,  and  in  what  follows  the  needs  of 
English  people,  inhabiting  a  temperate  though  most  variable  and  fickle 
climate,  will  be  mainly  held  in  view. 

In  dealing  with  the  subject  of  clothing,  we  shall  first  of  all  pass  in  review 
the  various  materials  which  are  chiefly  used  for  the  manufacture  of  clothes. 

We  shall  next  deal  with  the  principles  which  should  guide  us  in  the 
selection  of  clothing,  and  finally  we  shall  discuss  the  details  of  clothing,  and 
endeavour  to  show  how  the  principles  previously  discussed  may  be  best 
apphed  to  the  clothing  of  the  different  regions  of  the  body. 

The  materials  used  for  clothing  are  mainly  derived  from  the  animal  and 
vegetable  kingdoms,  minerals  being  employed  only  to  a  very  limited  extent 
for  the  production  of  the  various  accessories  of  clothing. 

The  materials  derived  from  the  vegetable  kingdom  are  cotton,  linen,  flax, 
hemp,  straw,  jute,  coir,  rhea,  and  some  other  fibres  of  less  common  use,  and 
also  gutta-percha  and  india-rubber. 

From  the  animal  kingdom  we  derive  furs,  skins,  leather,  feathers,  silk, 
and  wool. 

The  inorganic  bodies  employed  in  the  manufacture  of  clothing  are  iron, 
steel,  and  brass  ;  glass  for  buttons,  &c. ;  the  precious  metals,  especially  for 
the  decoration  of  military  uniforms  ;  and,  to  a  very  limited  extent,  asbestos. 

Wool  is  a  modification  of  hair,  and  is  furnished  by  the  sheep,  alpaca, 


510  HYGIENE 

Angora  goat  (mohair),  the  Cashmere  goat,  camel,  and  other  animals.  Fibres 
of  wool  (see  Plate  VI.  d)  have  upon  their  sm-face  imbricated  scales  which 
all  run  in  one  direction,  so  that  a  fibre  is  easily  pulled  through  the  fingers 
from  root  to  point,  but  not  so  easily  in  the  opposite  direction.  ^  These 
imbrications  cause  woollen  fibres  to  adhere  tightly,  and  make  it  diflicult  to 
miravel  closely  woven  woollen  textiles.  '  Under  the  influence  of  moisture 
and  pressure,  tangled  masses  of  wool  thoroughly  interlock  and  mat  together 
by  the  mutual  clutching  of  the  serrations  of  the  fibres,  and  it  is  thus  that 
the  shrinking  and  thickening  of  woollen  textures  under  washing  is  accounted 
for,  and  the  capacity  of  the  cloth  for  felting  or  fidling  is  due  to  this  condition 
of  the  fibre  '  (Paton).  The  serrations  are  most  numerous,  acute,  pointed, 
and  distinct  in  fine  merino  wools,  as  many  as  2,800  per  inch  being  counted 
in  specimens  of  the  finest  Saxony  wools.  In  the  Leicester  wool  of  England 
the  serrations  are  less  pronounced,  and  number  only  about  1,800  to  the  inch, 
so  that  the  fibre  is  smoother  and  less  waved.  In  some  inferior  wools  the 
serrations  are  not  so  many  as  500  to  the  inch.  A  similar  difference  exists 
in  the  fineness  of  the  fibre,  which  varies  from  -j;^^  inch  in  Saxony  wool  to 
■2  j-5-  in  coarse  Algerian  wools. 

By  various  manufacturing  processes  wool  assumes  very  different  aspects : 
cloth,  flannel,  blanket,  worsted  fabrics,  linitted  fabrics,  are  familiar  examples. 
Felt  is  made  without  spinning  or  weaving,  simply  by  the  cohesion  of  the 
imbricated  fibres. 

'  Shoddy  '  is  made  from  woollen  rags,  which  are  first  torn  asunder  by  a 
machine  called  a  '  devil,'  and  then  re-spun  and  re-woven,  with  a  certain  ad- 
mixture of  fresh  wool.  Shoddy  has  not  the  wearing  properties  of  new  wool, 
but  is  useful  for  Hnings,  rugs,  wraps,  druggets,  blankets,  &c. 

Wool,  according  to  Parkes,  is  soluble  in  a  strong  solution  of  liquor  potassae 
or  liquor  sod£e,  while  vegetable  fibres  are  not  attacked.  It  is  little  altered  by 
lying  in  sulphuric  acid,  it  is  thiged  yellow  by  nitric  and  picric  acids,  and  is 
scarcely  acted  upon  by  an  ammoniacal  solution  of  cupric  hydrate  (cupram- 
monia)  or  by  a  hot  concentrated  solution  of  zinc  chloride,  which  dissolves  silk. 
Wool  is  more  porous  and  more  hygroscopic  than  vegetable  fabrics,  and 
is  a  shghtly  less  perfect  conductor  of  heat.  While  it  absorbs  moisture 
readily,  it  gives  it  off  slowly,  so  that  far  less  cold  is  produced  by  the  evaporation 
from  a  woollen  garment  than  from  one  made  of  vegetable  fibre.  It  conserves 
the  heat  of  the  body,  and  protects  it  from  the  heat  of  the  sun,  the  latter 
property  being  at  its  height  if  the  garment  be  white. 

Silk  (see  Plate  VI.  c),  is  a  fibre  produced  by  the  Bomhyx  Mori  or  mulberry 
silk  moth.  According  to  Chinese  tradition,  the  introduction  of  the  silk  in- 
dustry was  due  to  an  empress  who  lived  more  than  2,000  years  B.C.  It  was 
not  until  the  alter  days  of  the  Eoman  empire  that  silk  fabrics  were  employed 
in  Europe,  and  for  a  long  period  it  remained  the  rarest  and  costliest  of  the 
textiles.  The  silk  glands,  one  on  each  side  of  the  body,  of  the  silkworm 
open  on  the  under  hp  of  the  larva  by  a  common  orifice.  The  secretion  of 
the  gland  is  a  sticky  fluid  which  hardens  on  exposure  to  the  air. 

Each  cocoon  furnishes  on  an  average  about  500  yards  of  reliable  silk. 
According  to  Mr.  James  Paton,  silk  fibre  consists  of  a  centre  or  core  of 
fibroin,  with  a  covering  of  sericin  or  silk  albumen,  and  a  little  waxy  and 
colouring  matter.  Fibroin  is  analogous  to  horn  and  hair,  and  its  composition 
is  represented  by  the  formula  CisH.^gN.rjOg.  It  is  insoluble  in  water,  alcohol, 
and  ether,  but  dissolves  freely  in  concentrated  alkaline  solutions,  mineral 
acids,  strong  acetic  acid,  and  ammonical  solution  of  cupric  hydrate.  Sericin, 
the  gummy  covering  of  the  fibre,  dissolves  readily  in  hot  soapy  solutions  and 
in  hot  water.     Silk  is  very  hygroscopic,  taking  up  as  much  as  30  per  cent. 


CLOTHING  611 

of  water  without  feeling  damp.  It  is  a  perfect  non-conductor  of  electricity. 
'  Silk  is  readily  distinguished  from  wool  and  other  animal  fibres  by  the 
action  of  an  alkaline  solution  of  oxide  of  lead,  which  darkens  wool  owing 
to  the  presence  of  sulphur,  but  docs  not  affect  silk.  Silk  dissolves  freely  in 
common  nitric  acid,  which  wool  does  not.  From  vegetable  fibres  silk  is 
readily  distinguished  by  the  bright  yellow  colour  given  by  picric  acid.  Micro- 
scopically also  the  fibres  are  distinguishable.  Manufactured  silk  is  of  two 
kinds,  reeled  silk  and  spun  silk,  the  latter  being  made  from  the  waste  and 
spoiled  cocoons  by  a  process  of  carding  and  spinning.  The  gloss  of  the  best 
silk  is  produced  by  a  process  of  scouring  by  means  of  which  the  external 
albuminous  coating  is  removed  and  the  raw  silk  loses  some  25  per  cent,  of 
its  weight.  Mr.  Paton  (art.  Silk,  '  Encyclopaedia  Brit.'  9th  ed.)  states  that 
in  order  to  obviate  this  loss  it  has  been  the  practice  to  dye  dark-coloured 
silks  without  scouring  them,  such  silks  being  known  as  '  souples.'  Silk 
absorbs  certain  metallic  salts  with  readiness,  and  more  readily  before  than 
after  scouring.  '  Up  to  1857  the  utmost  the  dyer  could  add  was  "  weight  for 
weight,"  but  an  accidental  discovery  in  that  year  put  dyers  into  the  way  of 
using  tin  salts  in  "  weighting,"  with  the  result  that  they  can  now  add  40  oz. 
per  pound  to  scoured  silks,  120  oz.  to  "  souples,"  and  as  much  as  150  oz.  to  spun 
silks,  and  yet  call  these  compounds  "  silk."  Not  only  so,  but  the  use  of  tin 
salts,  especially  stannic  chloride  (SnCl4),  enables  dyers  to  weight  all  colours 
the  same  as  black.'  In  his  '  Eeport  on  English  Silk  Industry  '  to  the  Eoyal 
Commission  on  Technical  Instruction  (1885),  Mr.  Thomas  Wardle,  of  Leek, 
says  : — '  Theproto-  and  per-salts  of  iron  as  weU  as  the  proto-  and  per-salts  of 
tin,  including  also  a  large  variety  of  tannin,  sumac,  divi-divi,  chestnut,  valonia, 
the  acacias  from  which  are  obtained  cutch  and  gambier,  &c.,  are  no  longer 
used  solely  as  mordants  or  tinctorial  matters,  but  mainly  to  serve  the  object 
of  converting  the  silk  into  a  greatly  expanded  fibre,  consisting  of  a  con- 
glomeration of  more  or  less  of  these  substances.  Sugar  is  also  largely  em- 
ployed to  weight  silk.' 

When,  therefore,  we  speak  of  '  silk  '  as  an  article  employed  in  the  manu- 
facture of  clothing,  the  word  is  used  in  a  conventional  sense  only,  since  from 
the  foregoing  it  appears  that  a  silk  garment  may  contain  as  little  as  10  per 
cent,  of  true  silk. 

Fiir. — The  warmest  variety  of  clothing  is  undoubtedly  fur,  which  has 
been  used  from  time  immemorial  by  northern  nations.  Fur  is  furnished  by 
certain  animals  inhabiting  cold  countries,  which  have  in  addition  to  their 
long  '  overhair '  a  dense  hairy  covering  which  is  called  fur.  A  skin  with  the 
fur  attached  forms  the  best  conceivable  protection  against  cold  and  wind. 
Furs  are  not  only  prized  as  affording  a  maximum  of  protection  to  the  body, 
but  they  are  also  in  great  demand  for  personal  adornment.  Ermine,  chin- 
chilla, bear,  seal,  and  marten  (Eussian  sable)  are  amongst  the  most  valued 
for  the  latter  purpose,  and  fetch  very  high  prices,  although  for  the  true 
purposes  of  clothing  they  are  in  no  way  superior  to  many  of  the  commoner  and 
cheaper  varieties  of  fur.  (For  microscopic  appearance  of  Rabbit  fur  see  Plate 
VI.  H.) 

Fur  is  also  used  for  making  felt,  the  hair  being  removed  from  the  skin  and 
by  a  process  of  compression,  combined  with  heat  and  moisture,  welded  into  a 
compact  and  cohesive  felt  owing  to  the  entanglement  of  the  hair  by  means  of 
the  microscopic  imbrications  on  its  exterior.  The  felts  used  for  clothing 
(mainly  head-coverings)  are  made  largely  from  hare  skins  and  rabbit  skins. 
Coarser  felts  used  for  carpets,  &c.,  are  mostly  made  from  cow  hair.  Felt  is 
a  fabric  of  great  antiquity,  and  it  is  considered  probable  that  a  knowledge 
of  felting  wool  preceded  a  knowledge  of  spinning  and  weaving. 


512  HYGIENE 

Leather  is  the  form  in  wliich  tlie  skins  of  animals  are  generally  used  for 
the  purposes  of  clothing.  By  tanning  and  alHed  processes  skins  are  made 
tough,  to  some  extent  impermeable,  supple,  and  not  liable  to  putrefy.  The 
skins  of  many  animals  are  used,  but  those  of  oxen  are  most  important,  the 
skins  of  horses,  goats,  sheep,  and  other  animals  taking  a  secondary  place. 
Skins  are  prepared  by  tanning,  tawing,  or  shamoying. 

Tanning  consists  in  steeping  the  skin  in  infusions  of  oak  bark  or  other 
bodies  containing  tannic  acid.  By  this  process  the  gelatin  of  the  hide  forms 
an  insoluble  compound  with  the  tannic  acid,  and  this  insoluble  compound  is 
the  basis  of  leather.  Oak  bark  imparts  firmness  and  sohdity  to  leather,  and 
the  high  quality  of  English  sole  leather  is  said  to  be  due  to  the  superiority 
of  the  EngUsh  oak  for  tanning  purposes.  Mimosa  bark,  hemlock  bark  (the 
bark  of  the  Abies  canadensis),  catechu,  and  other  bodies  are  also  largely  used 
for  tanning. 

To  make  the  best  quality  of  sole  leather  nearly  a  year  is  necessary,  and 
although  many  modern  inventions  have  been  used  for  shortening  the  process 
the  results  in  no  case  have  been  entirely  satisfactory,  and  there  now  seems 
to  be  no  doubt  that  a  slowly  operating  process  produces  the  best  leather. 

Lighter  leathers,  which  are  used  for  the  uppers  of  boots,  are  finished  by 
the  currier,  who  removes  inequaUties  from  the  hides,  impregnates  them  with 
grease,  'grains'  the  surface,  and  finally  coats  them  with  oil,  lamp-black,  and 
tallow. 

The  process  of  taiving  is  that  of  impregnating  skins  with  mineral 
astringents,  such  as  alum,  and  it  is  apphed  to  many  light  leathers,  such  as 
to  kid  uppers  of  boots.  Eecently  this  process  has  been  applied  to  heavier 
leathers,  bichromate  of  potash  being  the  chemical  employed.  It  is  said 
that  by  this  process  light  skins  can  be  prepared  in  less  than  a  week,  ox  and 
buffalo  hides  in  a  fortnight,  and  the  thickest  hides,  such  as  walrus,  in  a  month. 
The  process  is  both  quick  and  cheap,  but  an  experienced  bootmaker  has  in- 
formed the  writer  that  skins  prepared  in  this  way  are  not  fitted  for  high-class 
goods,  as  the  leather  is  apt  to  become  stiff  and  harsh;  and  this  same 
practical  authority  is  of  opinion  that  nothing  can  replace  time  in  the  pre- 
paration of  good  leather. 

Shamoying  is  employed  for  light  skins  only,  and  consists  in  impregnating 
the  skin  with  fish  oil,  which  undergoes  a  process  of  oxidation  within  the 
pores  of  the  skin,  the  result  being  the  well-known  shamoy  (chamois)  leather, 
which  is  not  unfrequently  used  for  under-garments. 

The  chemical  basis  of  vegetable  fibre  used  for  textile  purposes  is  cellulose, 
to  which  chemists  have  assigned  the  empirical  formula  of  CeHjoOg,  and  the 
percentage  composition  of  which  is  (according  to  F.  Schulze) 

C 44-0 

H 6-4 

0 49-6 

Nearly  all  cellulose  contains  a  certain  proportion  of  mineral  constituents 
(from  0*1  to  0"2  per  cent.),  so  that  when  vegetable  textiles  are  burnt,  the 
ash  retains  the  original  form  of  the  fabric.  There  is  also  from  7  to  9  per 
cent,  of  hygroscopic  moisture,  the  mean  variation  of  which,  according  to  the 
state  of  the  atmosphere,  amounts  to  about  1  per  cent. 

Cellulose  is  httle  acted  upon  by  most  solvents.  The  best  solvent  for 
cellulose  is  cuprammonia.  According  to  j\Ir.  C.  F.  Cross,  the  writer  on 
'  Cellulose  '  in  Watts's  '  Dictionary  of  Chemistry,'  the  best  method  of  effect- 
ing this  solution  is  to  place  the  material  with  some  copper  turnings  in  a  tube 
which  is  narrowed  below  and  pro^^ded  with  a  stopcock.     Strong  ammonia 


CLOTHING  513 

is  poured  upon  the  contents  of  the  tuhe,  and  after  standing  for  some  minutes 
is  drawn  off  and  returned  to  the  tube  ;  the  operation  is  several  times  re- 
peated, until  the  solution  of  the  substance  is  effected.  '  The  property  of 
cellulose  of  being  dissolved  by  cuprammonia  receives  an  important  technical 
apphcation.  A  sheet  of  paper  left  for  a  short  time  in  contact  with  the 
cuprammonia,  so  that  the  constituent  fibres  are  superficially  attacked,  and 
then  passed  between  rollers  and  dried,  becomes  impervious  to  water,  and  its 
cohesion  is  not  affected  at  the  boiling  heat.' 

The  reagent  which  is  chiefly  used  for  the  detection  of  cellulose,  a  reagent 
which  is  applicable  to  microscopic  work,  is  a  mixture  of  zinc  chloride,  and 
iodine  thus  prepared.  Zinc  is  dissolved  to  saturation  in  hydrochloric  acid, 
and  the  solution  evaporated  to  the  sp.  gr.  2*0  ;  to  ninety  parts  of  this  solution 
are  added  six  parts  of  potassium  iodide  in  ten  parts  of  water,  and  in  this  solu- 
tion iodine  is  dissolved  to  saturation.  By  this  reagent  cellulose  is  coloured 
uistantly  a  deep  blue  or  violet. 

Cotton,  which  is  by  far  the  most  important  of  all  vegetable  fibres  used 
for  textile  purposes,  is  the  downy  hair  attached  to  the  seeds  of  plants  belong- 
ing to  the  genus  Gossypium  of  the  natural  order  MalvaceaB.  Cotton  garments 
were  in  use  among  the  inhabitants  of  China  and  India  at  a  date  prior  to  the 
Christian  era,  and  the  Mexicans  and  Peruvians  were  found  to  possess  cotton 
textiles  in  the  sixteenth  century. 

It  was  not  till  1770  that  the  planters  of  the  Southern  States  of  America 
turned  their  attention  to  cotton,  and  it  is  said  that  the  first  bales  of  American 
cotton  came  to  Liverpool  shortly  before  that  date,  and  remained  many 
months  unsold. 

The  fruit  of  the  cotton  tree  consists  of  a  capsule  containing  from  three 
to  five  valves,  and  as  many  divisions,  holding  a  number  of  seeds.  These 
seeds  are  each  surrounded  by  a  flock  of  cotton,  which  becomes  swollen  when 
the  seed  reaches  maturity  and  the  valves  consequently  open.  The  cotton 
and  the  seeds  are  pulled  off,  and  after  drying  in  the  sun  are  separated  from 
each  other  by  the  process  of  '  ginning.' 

The  quality  of  the  cotton  is  judged  by  the  length  of  its  fibres,  which  vary 
from  half  an  inch  to  an  inch  in  length.  Cotton  filaments  when  fully  ripe,  but 
not  dried,  exhibit  under  the  microscope  a  membranous,  hollow,  cylindrical 
tube,  closed  at  both  ends.  When  dried  it  becomes  flattened  and  twisted,  and 
assumes  a  ribbon-like  shape,  rather  thicker  at  the  edges  than  in  the  middle. 
(See  Plate  VI.  b.) 

Cotton  consists  mainly  of  cellulose,  but  there  is  also  in  cotton  yarn, 
according  to  Dr.  Schunk,  about  "3  per  cent,  of  organic  matter,  consisting  of 
(1)  cotton  wax,  (2)  margaric  acid,  (3)  a  colouring  matter  easily  soluble  in 
alcohol,  (4)  a  colouring  matter  soluble  with  difficulty  in  alcohol,  (5)  pectic 
acid,  (6)  albuminous  matter. 

In  the  course  of  manufacture  cotton  goods  are  subjected  to  a  great 
variety  of  processes.  After  the  weaving  comes  the  bleaching,  and  then  the 
*  finishing '  of  goods  for  the  market.  Among  the  finishing  processes  are 
mangling,  starching,  damping,  '  beetling ' — which  is,  in  fact,  hammering  by 
machinery — and  calendering,  which  consists  of  pohshing  by  means  of  a 
machine  which  has  been  evolved  from  the  mangle. 

On  the  subject  of  '  starching  '  Mr.  J.  Paton,  whose  valuable  articles  in  the 
'  Encyclopaedia  Britannica  '  we  have  frequent  occasion  to  quote,  says  : — '  It  is 
in  this  stage  that  so  much  is  done  by  some  bleachers  to  give  cloth  a  factitious 
appearance  of  weight  and  bulk  by  filling  up  the  interstices  between  the 
fibres  with  compounds  which  have  no  other  object  than  to  please  or  deceive 
the  eye,  and  some  of  which  have  a  decidedly  deleterious  influence  on  the 

VOL.    I.  L  Ii 


514  HYGIENE 

tissues  they  are  intended  to  improve  in  appearance.  A  gi-eat  variety  of 
mixtures,  both  cheap  and  nasty,  are  used  by  some  finishers  in  place  of 
starch  with  a  view  to  produce  weight  and  appearance  ;  but,  naturally,  as 
little  information  as  possible  on  this  point  is  permitted  to  leak  out  to  the 
public' 

Pure  starch  is  alone  used  by  reputable  bleachers,  but  why  even  this  is 
necessary  it  is  not  quite  clear  to  one  who  is  only  a  purchaser  and  not  a 
manufacturer  of  calicoes.  The  same  writer,  in  his  article  on  calico  printing, 
has  some  instructive  remarks  concerning  the  use  of  aniline  colours,  which  he 
says  '  now  constitute  the  largest  and  most  important  section  of  steam-fixed 
dyeing  materials.'  ...  '  The  process  of  fixing  these  colours  now  generally 
adopted  is  known  as  the  arsenite  of  alumina  process.  In  this  process  the 
dye  is  dissolved  in  water  or  acetic  acid,  carefully  filtered  through  a  fine  cloth 
and  mixed  with  acetate  of  alumina,  a  thickener,  and  arsenious  acid  dissolved 
in  glycerine.  This  mixture  is  printed  on  the  cloth,  which  is  then  introduced 
into  the  steaming  chest.  In  the  steaming,  acetic  acid  is  liberated  and  arsenite 
of  alumina  formed,  which  with  the  aniline  colour  is  precipitated  in  the  fibres 
as  a  brilliant  insoluble  lake.' 

From  this  it  appears  that  aniline  colours  in  respect  of  their  toxic  poten- 
tialities may  be  in  no  respect  superior  to  those  in  which  compounds  of  arsenic 
have  avowedly  been  used. 

Flax  has  been  from  the  earliest  periods  of  the  world's  history  one  of  the 
most  important  of  the  textile  fibres.  There  is  evidence  that  it  was  in  use 
by  the  Swiss  lake  dwellers,  and,  coming  down  to  historic  times,  there  is  no 
doubt  that  it  was  extensively  employed  for  clothing  by  the  Egyptians.  This 
fibre  is  obtained  from  the  stalks  of  Linum  usitatisswnLm  and  other  varieties 
of  the  flax  plant.  The  plants  when  approaching  ripeness  are  pulled  up  by 
the  roots  and  the  seed  capsules  or  '  bolls '  are  separated,  the  processes  being 
technically  known  as  '  pulling  and  rippling.'  The  rippled  stalks  are  then 
tied  in  bundles  and,  being  steeped  in  water,  are  exposed  on  the  grass  to  the 
dew,  and  undergo  a  process  of  putrefactive  fermentation  technically  known  as 
'  retting,'  or  '  rotting,'  whereby  the  gummy  and  other  matters  are  separated 
from  the  fibres.  Finally  the  fibre  is  prepared  for  the  market  by  being  beaten 
and  combed  in  the  process  known  as  '  scutching.'  The  plants  yield  about 
6  per  cent,  of  marketable  fibre. 

Hugo  Miiller  gives  the  composition  of  best  Belgian  flax  as  follows  : — 

Ash 0-70 

Water 8-65 

Extractive     .........  3'65 

Fat  and  wax  .........  2-39 

Cellulose 82-57 

Intercellular  substance  and  pectose  bodies    .         .         .  2-74 

Total  .  100-70 
Microscopically  the  flax  fibre  is  seen  to  be  marked  at  regular  intervals  by 
transverse  striae,  which  indicate  the  divisions  of  the  cells  of  which  the  fibre 
is  composed.  According  to  Wiesner,  the  width  of  the  fibre  varies  from  -012 
to  '025  millimetre,  and  the  length  of  the  individual  cells  varies  from  two  to 
four  milhmetres,  while  the  fibre  as  a  whole  ranges  in  length  from  20  to 
140  centimetres.     (See  Plate  VI.  a.) 

Mr.  James  Paton,  in  his  article  on  linen  in  the  '  Encyclopaedia  Britannica,' 
says  that  linen  is  much  smoother  and  more  lustrous  than  cotton  cloth  ;  and, 
presenting  a  less  '  woolly '  surface,  it  does  not  soil  so  readily,  nor  absorb,  nor 
retain  moisture  so  freely,  as  the  more  spongy  cotton  ;  and  it  is  at  once  a  cool, 
clean,  and  healthful  material  for  bed-sheeting  and  clothing.     Bleached  linen, 


[  Tr  e  sLti  s  e  on  Hy §  xe  n  e .] 
Vol.1. 


PI.  VI 


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IVfest^Newiaaji  iiop. 


CLOTHING  515 

starched  and  dressed,  possesses  that  unequalled  purity,  gloss,  and  smoothness 
which  make  it  alone  the  material  suitable  for  shirt  fronts,  collars,  and  wrist- 
bands ;  and  the  gossamer  delicacy,  yet  strength,  of  the  thread  it  may  be  spun 
into  fits  it  for  the  fine  lace-making  to  which  it  is  devoted.  Flax  is  a  heavier 
material  than  cotton,  but  weight  for  weight  it  is  much  stronger,  single  yarn 
having  proportionate  strength  in  the  ratio  of  3  to  1"83,  double  yarn  3  to  2-20, 
and  cloth  3  to  2-13. 

Bhea  is  a  fibre  obtained  from  one  or  more  species  of  Bohmeria,  plants 
resembling  nettles,  and  of  the  same  natural  order  (Urticacete),  growing  in 
India,  China,  and  elsewhere  in  tropical  and  sub- tropical  districts.  As  far  as 
the  writer  is  aware,  it  has  not  been  used  for  clothing,  but  it  is  likely  that 
modern  and  improved  methods  of  preparation  may  render  it  available  for 
that  purpose,  and  therefore  it  is  included  in  this  article. 

Jwfe  is  a  fibre  obtained  from  Corc/iorws  capsularis  and  Corchorus  olitorius 
plants,  of  the  natural  order  Tiliacese,  which  are  grown  for  manufacturing 
purposes,  mainly  in  Bengal.  Jute  fibre  is  brittle  and  very  hygroscopic  (see 
Plate  YI.  g).  It  is  used  mainly  for  coarse  textiles,  such  as  sacking,  mats,  &c. 
In  India  it  is  used  to  a  limited  extent  for  the  manufacture  of  clothing,  and  in 
■this  country  it  is  said  to  be  employed  for  the  adulteration  of  other  textiles, 
such  as  silk,  and  also  in  the  manufacture  of  false  hair. 

Hemp,  the  fibre  obtained  from  Cannabis  sativa,  is  mentioned  by  Herodotus 
.as  being  used  by  the  Scythians  for  the  manufacture  of  their  garments  (see 
Plate  VI.  b). 

Coir  is  a  coarse  fibre  obtained  from  the  outer  husk  of  the  cocoa-nut.  It  is 
;much  used  for  mats,  ropes,  and  coarse  work,  but  its  use  for  clothing  is  ex- 
tremely limited  (see  Plate  VI.  f). 

India-rubber,  or  caoutchouc,  is  an  article  of  clothing  of  great  and  growing 
importance,  although  of  comparatively  modern  introduction.  It  is  elastic 
.and  absolutely  impermeable  to  water.  The  former  property  is  of  service  in 
various  accessories  of  clothing,  such  as  the  '  side-springs  '  of  boots,  while  the 
latter  is  made  use  of  in  the  manufacture  of  the  great  bulk  of  waterproof 
■clothing.  The  first  use  of  india-rubber  for  waterproofing  clothes  seems  to 
have  been  made  by  the  Spaniards  in  Mexico  in  the  beginning  of  the  sixteenth 
century,  but  its  extensive  use  dates  only  from  the  beginning  of  the  present 
century.  Caoutchouc  is  obtained  from  the  milky  juice  of  several  plants 
growing  in  Asia,  Africa,  and  South  America.  Among  the  plants  which  yield 
caoutchouc  are  the  Hevea  braziliensis  and  the  Manihot  Glaziovii,  two 
Euphorbiaceous  trees  growing  in  South  America,  and  the  Ficus  elastica,  an 
East  Indian  plant  growing  in  Assam  and  elsewhere  in  the  Himalayan  dis- 
trict. The  plants  named,  however,  are  only  three  out  of  several  which  yield 
this  valuable  product.  Caoutchouc  has  its  elasticity  impaired  and  destroyed 
fey  a  freezing  temperature,  and  it  undergoes  a  contraction  at  temperatures 
a  little  above  blood  heat,  while  at  still  higher  temperatures  it  softens  and 
melts.  Caoutchouc  is  a  complex  body  ;  it  is  porous  and  absorbs  water  (i.e. 
in  its  raw  state)  when  submitted  to  prolonged  soaking.  Among  its  pecuhar 
properties  is  the  one  that  freshly  cut  surfaces  unite  firmly — a  fact  of  which 
the  chemist  and  the  manufacturer  make  abundant  use.  Among  the  solvents 
of  caoutchouc  are  benzene,  carbon  disulphide,  petroleum,  ether,  and  chloroform. 
Most  fatty  substances  destroy  caoutchouc,  making  it  first  soft  and  then  hard 
and  brittle,  and  to  this  fact  is  due  the  frequent  damage  done  to  water-pillows, 
&c.,  in  hospitals.  '  Vulcanisation  '  is  effected  by  steeping  the  caoutchouc  in 
melted  sulphur,  maintained  at  a  temperature  of  140°  C,  and  by  other  methods. 
Macintosh  cloth  is  made  by  spreading  on  layer  after  layer  of  caoutchouc  paste 
in  solution  on  a  cotton  or  silk  textile,  but  into  the  details  of  manufacture  it 

n,2 


51G  HYGIENE 

is  not  our  province  to  enter.  For  most  of  the  above  facts  the  ^^Titer  is  in- 
debted to  an  article  by  Messrs.  Holmes  and  Bolas  in  the  '  Encyclopaedia 
Britannica '  (9th  edition). 

Gutta-percha  is  of  secondai-y  importance  as  an  article  of  clothing,  as  its 
use  in  this  direction  is  almost  limited  to  the  occasional  manufacture  of  boot 
soles.  This  material,  like  india-rubber,  is  furnished  by  the  lacticiferous  vessels 
of  certain  trees,  and  the  distribution  of  these  trees  is  almost  limited  to  the 
Malay  Peninsula,  and  to  about  six  degrees  north  and  south  of  the  Equator. 
Seeing  that  the  trees  in  order  to  produce  gutta-percha  have  to  be  felled,  and 
that  the  artificial  cultivation  of  the  tree  is  not  practised,  there  is  some  reason 
to  fear  that  this  article  may  become  scarce. 

Inorganic  bodies  are  of  very  limited  use  for  clothing,  now  that  plate  and 
chain  armour  are  no  longer  worn.  The  metals  are,  however,  much  used  for 
the  indispensable  accessories  such  as  hooks-and-eyes,  buttons,  nails  and  tacks. 
Metal  springs  are  perhaps  too  much  used  in  the  manufacture  of  women's  corsets. 

Asbestos  is  occasionally  used  for  making  fire-proof  gloves,  and  it  is  said 
that  quite  fine  textiles  may  be  made  of  it,  and  that  the  ancients  used  to  wrap 
their  dead  in  asbestos  cloth.  It  cannot  fairly  be  regarded  as  an  article  used 
for  clothing.  The  same  may  be  said  of  '  spun  glass,'  which  may  still  be  seen 
occasionally  decorating  the  head  of  a  State  coachman.  Mineral  and  other 
matters  are  abundantly  used  as  adulterants  for  fabrics,  in  order  to  give  weight 
and  a  fictitious  amount  of  substance,  and  there  is  reason  to  think  that  this  is 
much  practised  in  the  production  of  corduroy,  moleskin,  and  similar  heavy 
materials  worn  by  the  labouring  classes.  In  the  Parkes  Museum  is  a  piece 
of  Manchester  '  goods,'  which  after  drying  at  212°  F.  weighed  608  grains. 
After  washing  and  again  drying  this  fabric  weighed  387  grains,  showing  that 
221  grains,  or  more  than  36  per  cent,  of  soluble  and  other  material  remov- 
able by  washing,  was  contained  in  it. 

The  remarks  which  we  have  incidentally  made  while  discussing  the 
fabrics  seriatim  will  have  shown  that  the  pm-chaser  is  very  liable  to  be 
deceived  as  to  quality.  At  the  Army  Clothing  Factory  in  Pimlico,  every 
precaution  is  taken  to  prevent  fraud  on  the  part  of  manufacturers. 

When  fabrics  arrive  in  the  bale  or  piece  they  are  first  of  all  weighed  and 
measured  by  a  machine  which  performs  both  operations  simultaneously  and 
with  great  rapidity.  In  this  way  assurance  is  obtained  that  length  and 
weight  bear  a  proper  proportion  to  each  other,  and  that  the  fabric,  whatever 
it  may  be,  is  of  the  desired  stoutness. 

The  next  process  is  called  '  perching.'  The  fabric  is  unfolded,  and  pass- 
ing over  a  roller  near  the  ceiling  descends  towards  the  floor.  This  is  done  in 
front  of  a  large  window,  so  that  the  '  right  side '  of  the  fabric  has  a  strong 
light  upon  it.  Two  scrutineers  stand  in  front  of  the  descendmg  fabric, 
between  it  and  the  window,  while  a  third  stands  behind  the  fabric  and 
watches  it  by  the  transmitted  light  of  the  window.  In  this  way  flaws  and 
blemishes  are  at  once  detected,  and  for  every  such  flaw  or  blemish  deductions 
are  made  from  the  contract  price.  Next  the  tearing  strain  is  tested  by  a 
machine,  which  records  the  number  of  pounds  of  tension  which  causes  the 
fabric  to  tear,  the  tearing  strain  being  fixed  by  contract.  The  next  step  is  to 
ascertain  that  no  fibre  has  been  used  in  the  manufacture  other  than  the  one 
contracted  for,  and  this  is  done  by  a  systematic  chemical  analysis  and  micro- 
scopic examination.  Finally,  the  dyes  used  are  chemically  examined.  In  this 
way  all  forms  of  deception  are  guarded  against. 

A  thoroughly  experienced  eye  is  a  tolerably  safe  guide  for  testing  fabrics. 
Such  an  eye  will  usually  detect  any  mixture  of  fibres,  and  will  be  able  to  judge 
of  the  quality  and  fineness  of  the  weaving.     It  is  said  that  good  materials 


CLOTHING  517 

'have  always  a  firm,  strong  selvage,  and  careful  housewives  generally  look  to 
this  point.  A  good  test  is  to  rub  the  fabric  briskly  between  the  hands  and 
against  the  light.  A  heavily  sized  and  starched  fabric  will  emit  a  cloud  of 
dust  under  this  test,  and  this  cloud  shows  that  it  is  very  nearly  worthless. 
Such  fabrics  appear  far  more  translucent  after  such  rubbing  than  they  did 
before,  and  it  will  generally  be  found  that  these  sized  articles  tear  very  readily, 
and  after  their  first  washing  their  real  flimsiness  is  abundantly  apparent. 

If  large  quantities  of  a  material  are  going  to  be  used,  it  would  always  be 
wise  to  obtain  a  sample  and  thoroughly  examine  and  wash  it  before  pur- 
chasing. In  this  way  its  genuineness  and  the  '  fastness  '  of  the  colours  may 
be  very  fairly  judged  of.  If  a  few  fibres  be  teazed  out  and  examined  by  the 
microscope,  one  may  obtain  almost  absolute  knowledge  as  to  the  composition 
of  the  fabric. 

A  great  deal  has  been  written  of  late  years  as  to  the  best  material  for 
■  clothing,  and  there  are  not  wanting  those  who  urge  that  the  'natural 
clothing  '  of  animals  is  the  '  natural '  and  only  proper  clothing  for  the  first 
of  all  animals — man.  An  assertion  of  this  kind  seems  to  us  to  be  in  some 
degree  similar  to  the  old  dogma  that  '  animal  heat '  was  different  from  other 
kinds  of  heat ;  a  plausible  theory  which  the  hatching  of  eggs  in  incubators  by 
means  of  artificial  heat  has  done  much  to  explode. 

There  can  be  no  doubt  that  wool  and  furred  skins  are  of  great  and  un- 
doubted value  as  articles  of  clothing,  and  that  they  will  be  eagerly  sought 
in  the  future  as  they  have  been  in  the  past.  To  assert,  however,  that  these 
are  the  only  proper  articles  from  which  to  manufacture  clothing  must  tend 
to  deprive  the  public  unnecessarily  of  the  numerous  vegetable  fibres,  which 
if  properly  manufactured  are  scarcely  inferior  for  many  purposes  to  garments 
made  of  wool. 

The  great  value  set  upon  wool  as  an  article  of  clothing  is  attributable  to 
the  alleged  fact  that  it  has  far  less  conducting  power  for  heat  than  either 
cotton  or  linen.  Thus  Parkes  ('  Practical  Hygiene,'  5th  edition)  quotes  the 
experiments  of  Coulier  and  Hammond  on  the  conducting  power  of  different 
materials.  'In  both  cases  a  polished  metallic  vessel  was  filled  with  hot 
water  of  a  known  temperature,  a  delicate  thermometer  inserted,  and  the 
vessel  was  hung  in  an  empty  room  ;  the  time  required  for  cooling  to  a  given 
point  when  the  vessel  was  uncovered  and  covered  by  different  fabrics  was 
noted  by  the  observer  at  a  distance  with  a  magnifying  glass.'  Coulier's 
experiments  gave  the  following  results  : — 

Time  required  for  Cooling  from  122°  F.  to  104°  F. 

Vessel  uncovered 18'  12" 

Vessel  covered  with  cotton  shirting 11'  30" 

„       linings 11' 15" 

hemp         „ 11' 25" 

„  blue  woollen  cloth  for  uniforms         .         .  14'  45" 

red  „  „  .         .         .  14' 50" 

,,  blue  ,,  great-coats      .         .  15'  5" 

It  scarcely  needs  an  experiment  to  show  that  a  material  used  for  a  great- 
coat is  a  worse  conductor  of  heat  than  a  piece  of  thin  shirting  or  lining,  and 
that  is  all  that  the  above  experiment  seems  to  us  to  show. 

To  test  the  thermal  conductivity  of  different  substances  is  a  most  difficult 
matter,  and  the  experiments  need  to  be  conducted  with  a  degree  of  precision 
and  delicacy  which  can  scarcely  be  overestimated.  Whether  a  great-coat  or 
a  shirt  conducts  the  better  is  not  the  question,  and  can  never  be  a  serious 
.question.     What  we  have  to  determine  is  the  difference,  if  any,  between  the 


518  HYGIENE 

thermal  conductivities  of  equal  fibres  of  ^vool,  cotton,  liemp,  or  linen  under' 
exactly  equal  conditions.  The  table  of  '  Thermal  Conductivities  '  given  by 
Su"  ^^'illiam  Thomson  in  his  article  '  Heat '  in  the  '  Encyclopiedia  Britannica ' 
(9th  edition)  seems  to  show  that  the  difference  between  different  fibres 
used  for  clothing  is  scarcely  appreciable. 

Copper,  according  to  this  table,  is  the  best  conductor,  its  conductivity 
being  represented  by  the  number  'Ol.  Iron  is  nearly  six  times  less  than 
copper,  its  conductivity  being  represented  by  the  number  '16. 

The  numbers  given  for  the  clothing  materials  are  so  small  that  they  may 
be  regarded  as  practically  non-conductors.     They  are  : — 

Wool  (carded)  of  all  densities -000122 

Calico  (new)  of  all  densities "OOOISO 

Hempen  cloth  (new)  ........  -000144 

Air -000049 

Water -002 

Cork -000029 

Eider-down -000108 

Air  is  one  of  the  worst  conductors  of  heat,  and  it  is  highly  probable  that 
the  power  of  different  clothing  materials  in  keeping  the  body  warm  depends- 
more  upon  the  amount  of  air  entangled,  so  to  say,  in  the  fabric  than  upon 
the  material  used  in  the  construction  of  the  fabric.  That  different  materials 
are  habitually  woven  in  different  ways  is  well  known,  and  the  fact  that  one 
material  is  '  warmer  '  than  another  is  often  due  to  the  fact  that  it  lends  itsell 
by  its  nature  to  a  particular  mode  of  manufacture.  Woollen  materials  are 
always  more  porous  than  linen  fabrics,  and  it  is  mainly  to  this  fact  that  the 
one  is  '  warmer '  than  the  other.  Anything  which  keeps  the  same  layer  of 
ah'  in  constant  contact  with  the  body  is  warm,  and  when  the  atmosphere,, 
though  cold,  is  perfectly  still,  a  thin  flannel  garment,  or  even  a  few  layers  of 
the  thinnest  gauze,  is  sufficient  to  keep  the  body  warm.  Anyone  who  has 
wrapped  a  newspaper  round  his  legs  in  default  of  a  railway  rug  has  con- 
vinced himself  of  this  fact. 

Nothing  chills  the  body  more  than  wind,  and  it  is  when  we  get  wind  and. 
cold  combined  that  thick  clothing  becomes  necessary.  In  some  of  the  high 
Alpine  valleys,  where  the  sun  is  powerful  and  there  is  an  absence  of  wind,, 
it  is  surprising  to  see  how  comparatively  lightly  the  inhabitants  are  clad,. 
notwithstanding  that  the  thermometer  in  the  shade  is  down  to  zero.  When,, 
however,  the  wind  gets  up,  warm  thick  clothing  and  furs  become  necessary. 
To  resist  wind,  clothing  must  be  thick,  or  the  layers  of  thin  clothing  must 
be  multiplied.  Wind  not  only  tends  to  renew  the  air  hi  contact  with  the 
body,  but  it  also  quickens  evaporation  from  the  surface  of  the  clothes,  which 
evaporation  is  in  itself  a  great  cause  of  the  chilling  of  the  body.  The  best 
garments  for  resisting  cold  and  wind  are  skins,  with  the  woolly  side  nearest 
the  skin.  Next  to  skins  come  thick  shaggy  woollen  clothes,  such  as  the  Scotch 
tweeds  and  Irish  friezes,  and  the  thick  great-coats  made  of  '  shoddy  '  which 
are  worn  by  our  poorer  classes.  After  these  come  closely  woven  cloths. 
Impermeable  materials  are  amongst  the  warmest  known,  because  they  are 
absolutely  wind-proof,  but  they  allow  moisture  to  collect  on  the  surface  of 
the  body,  and  as  the  material  is,  from  its  absolute  want  of  porosity,  a  com- 
paratively good  conductor  of  heat,  and  as  the  accumulated  perspiration  is 
also  a  good  conductor,  the  body  is  very  liable  to  get  chilled  if  they  be  worn 
continuously.  '  Macintosh  '  clothing  is  of  undoubted  and  great  value  for 
certain  purposes,  especially  for  coachmen,  with  whom  the  exposure  is  great 
and  the  tendency  to  perspiration  small.  They  are  very  dangerous  garments- 
for  use  during  active  exercise. 


\ 


CLOTHING  510 

The  Chinese*  clothing  is  often  in  many  layers,  each  layer  being  in  cut 
and  form  almost  precisely  like  its  fellow,  and  by  diminishing  or  increasing 
the  various  layers  they  are  accustomed  to  meet  the  vicissitudes  of  their 
climate.  This  is  a  sound  principle,  and  one  which  we  may  often  adopt  with 
advantage.  It  is  recorded  that  Charles  I.  on  the  day  of  his  execution,  which 
was  bitterly  cold,  put  on  two  linen  shirts  in  order  that  he  might  not  shiver ; 
an  act  which  might  have  been  attributed  by  the  populace  to  fear. 

The  porosity  of  woollen  fabrics  constitutes  the  chief  but  not  the  only 
claim  to  their  deserved  popularity.  It  is  possible,  however,  to  imitate  this 
quality  of  wool  by  weaving  linen  or  cotton  in  a  loose  porous  fashion,  these 
fabrics  then  becoming,  as  heat- retainers,  scarcely  inferior  to  wool.  Such 
fabrics  are  now  abundantly  made,  but  we  do  not  deem  it  our  duty  to  bring 
to  the  notice  of  the  reader  the  wares  of  any  particular  tradesman. 

The  hygroscopic  or  absorbent  power  of  the  material  for  water  is  a  very 
important  matter.  It  is  commonly  asserted  that  the  hygroscopic  qualities 
of  wool  are  far  greater  than  those  of  the  other  fibres.  Silk,  as  we  have 
seen,  is  powerfully  hygroscopic,  as  also  is  jute,  while  cellulose,  the  basis 
of  all  vegetable  fibres,  usually  contains  from  8  to  10  per  cent,  of  hygroscopic 
moisture.  There  can  be  no  doubt  that  as  a  broad  rule  woollen  fabrics  absorb 
or  sop  up  far  more  moisture  than  cotton.  This  is  partly  due  to  the  form  in 
which  the  manufactured  article  is  woven.  If  we  compare  flannel  with 
calico,  the  absorbing  power  is  most  marked  in  the  flannel,  but  if  we  compare 
some  very  closely  woven  and  fine  woollen  fabric  with  a  piece  of  cotton  bath- 
towelling,  the  absorbent  power  may  be  perhaps  greatest  in  the  latter.  It  is 
a  question  how  far  fabrics  made  of  vegetable  fibre  may  be  made  to  equal 
woollen  fabrics  in  their  power  of  absorption.  A  fabric  which  is  really 
hygroscopic  will  absorb  a  great  deal  of  water  without  feeling  wet,  and  this 
power  is  to  be  distinguished  from  the  power  of  merely  holding  water  in  the 
interstices  of  the  fibres.  Common  experience  is  probably  sufficient  to  prove 
that  wool  is  far  more  hygroscopic  than  vegetable  fibres,  but  these  latter  are 
certainly  more  hygroscopic  than  generally  is  allowed.  Flannel  absorbs 
moisture  readily,  and  owing  to  its  high  hygroscopic  power  evaporation  from 
its  surface  is  slow.  When,  therefore,  a  man  sweats  in  a  woollen  garment 
the  garment  does  not  get  wet  through,  and  the  evaporation  being  gradual 
the  chilling  of  the  body  when  exercise  ceases  is  comparatively  slight.  When 
a  man  sweats  in  an  ordinary  close-woven  linen  or  cotton  garment,  the  gar- 
ment gets  wet  through  and  adheres  to  the  skin,  and  the  evaporation  being 
rapid  the  chilling  of  the  surface  is  great,  the  body  being,  in  fact,  covered 
with  an  '  evaporating  lotion.'  This  latter  evil  may  undoubtedly  be  to  some 
extent  counteracted  by  a  looser  method  of  weaving  the  material. 

For  work  in  a  climate 'like  ours  flannel  is  the  safest  material  to  wear,  or 
if  cotton  or  linen  be  worn  it  must  be  loose- woven,  so  as  to  give  some  thickness 
and  porosity  to  the  fabric. 

In  tropical  countries  flannel  is  too  heavy  a  material,  and  linen  or  cotton 
shirting  is  very  generally  worn,  and  great  discomfort  is  experienced  by  its 
getting  soaked  and  adhering  to  the  skin.  This  trouble  has  been  met  by  the 
Cliinese,  who  have  been  accustomed  in  hot  weather  to  wear  a  net  next  the 
skin  and  a  thin  silken  garment  over  the  net.  The  net,  without  increasing 
the  heat,  prevents  the  sweat  soaking  into  the  upper  garment,  and  the  latter 
from  adhering  to  the  skin,  and  nothing  can  be  conceived  more  suitable  for 
tropical  heat  than  such  an  arrangement. 

For  preventing  the  effects  of  solar  rays  upon  the  body  the  colour  of  the 
fabric  worn  is  all-important.  White  garments  absorb  least  heat,  and  are 
the  best  for  the  tropics.     Next  to  white  for  resisting  the  effects  of  sun-heat 


520  HYGIENE 

are  tlie  light  shades  of  colour.     Blue  aiid  black  are  the  worst,  and  absorb 
heat  very  readily. 

We  are  now  in  a  position  to  discuss  the  articles  of  clothing  employed  for 
difl'erent  regions  of  the  body. 

The  head  first  demands  our  attention.  Being  provided  with  a  natural 
covering  in  the  shape  of  hair,  it  really  requires  no  additional  clothing,  as  the 
state  of  well-being  enjoyed  by  the  London  Blue  Coat  boys  sufficiently  shows  ; 
but  the  usages  of  society  render  it  inadmissible  to  go  without  a  head-cover- 
ing of  some  kind — at  least  out  of  doors — and  a  man  who  is  accustomed  to 
wear  a  hat  is  tolerably  certain  to  catch  cold  if  he  goes  without  one. 

The  hair  of  a  man  should  be  worn  short,  and  the  shorter  it  is  the  more 
readily  it  is  kept  clean  and  tidy.  When  the  hair  is  short  it  can  be  washed 
almost  as  easily  as  any  other  part  of  the  body,  and  in  a  town  such  as  London, 
where  the  atmosphere  is  laden  with  soot  and  dirt,  the  frequent  Avashing  of 
the  head  is  an  absolute  necessity.  The  custom  of  applying  some  pomade 
to  the  bair  is  very  general,  and  it  is  probably  a  good  custom  ;  when  the  hair 
is  slightly  oiled  it  can  be  the  more  readily  combed,  and  the  combing,  brushing, 
and  oiling  serve  very  materially,  not  only  to  keep  the  hair  clean,  but  to  free 
it  from  vermin  as  well.  A  little  oil  or  similar  material  having  a  basis  of 
glycerine  or  vaseline  also  prevents  the  drying  of  the  skin  of  the  scalp  and 
checks  the  tendency  which  the  surface  epithehum  has  to  come  off  in  the  form 
of  scurf  or  dandrifl".  A  very  greasy  head  not  only  looks  disagreeable,  but  from 
its  stickiness  it  enables  dirt  easily  to  lodge  upon  and  adhere  to  the  hair. 
The  abuse  of  pomades  is  to  be  decried  from  every  point  of  view ;  but  the 
'  pennyworth  of  hair  oil,'  which  forms  so  important  an  adjunct  of  the 
Sunday  toilet  of  the  working  classes,  is  not  to  be  discouraged. 

It  is  quite  possible  to  go  without  a  hat  in  any  climate,  and  natives  of  the 
tropics  who  wear  the  hair  short  and  have  no  artificial  covering  for  the  head 
do  not  seem  to  be  liable  to  sunstroke,  nor  are  their  eyes  dazzled  by  the  glare 
of  the  sun. 

In  very  cold  regions  also  the  hair  if  tolerably  thick  is  sufficient  protec- 
tion for  the  head,  and  might  also  be  made  to  cover  the  ears  ;  but  if  the  hair 
be  not  thick,  then  a  head-covering  becomes  a  necessity,  and,  as  a  matter  of 
fact,  most  of  the  inhabitants  of  northern  climates  find  it  convenient  to  cut 
the  hair  and  cover  the  head  with  a  fur  cap  having  lappets  for  the  ears. 

For  ordinary  use  in  a  climate  like  England  the  selection  of  a  hat  is  not 
a  very  important  matter,  the  main  consideration  being  the  comfort  of  the 
wearer.  It  is  important  to  have  a  layer  of  air  between  the  top  of  the  head 
and  the  crown  of  the  hat,  for  in  this  way  the  effects  of  cold  and  heat  are 
ahke  avoided.  It  is  also  advisable  to  have  a  certain  amount  of  rigidity  in 
the  hat  as  a  protection  for  the  head  from  the  effects  of  falls  or  accidental 
blows.  The  low-crowned  hemispherical  hat  of  felt  with  a  brim  sufficient 
to  protect  the  eyes  from  glare  and  to  keep  rain  from  running  down  the 
neck  meets  most  of  the  indications  above  mentioned,  and  its  popularity  ig 
quite  justifiable.  The  tall  cylindrical  '  chimney  pot '  hat  made  of  silk  is  by 
no  means  a  bad  headdress,  notwithstanding  the  abuse  which  is  levelled  at 
it.  It  is  not  very  heavy  (at  least  it  need  not  be),  it  has  sufficient  stiffness 
to  protect  the  head,  and  the  large  stratum  of  air  between  the  head  and  the 
crown  of  the  hat  is  excellent.  The  comparative  narrowness  of  the  brim, 
the  cylindrical  shape,  and  the  smooth  surface  make  it  difficult  to  be  blown 
off,  a  point  of  no  small  importance.  Its  great  drawback  is  its  cost  and  the 
ease  with  which  it  is  damaged  by  rain.  A  shabby  hat  of  this  description 
gives  an  air  of  shabby  gentility,  and  there  is  nothing  which  more  degrades 
i.he  appearance  of  a  man  than  a  mangy  hat  which  has   seen  better  days. 


CLOTHING  ,  521 

Some  of  these  hats  are  made  to  '  ventilate,'  with  the  idea  of  keeping  the 
head  cool.  A  drawback  to  the  two  varieties  of  hat  mentioned  is  the  difficulty 
of  keeping  them  clean,  but  in  this  respect  the  cylindrical  hat  is  usually 
better  than  the  hemispherical  '  deer-stalkers.'  These  catch  the  dust  very 
badly,  and  the  combination  of  dust  and  rain  spoils  them  very  rapidly.  Dust 
lodges  especially  round  the  brim,  and  the  brim  is  of  such  a  shape  that  only 
brushes  of  a  very  special  make  will  clean  it.  Every  traveller  must  have 
experienced  the  shortcomings  of  these  hats,  and  it  is  much  to  be  desired  that 
the  curl  to  the  brim  and  the  conventional  bow  of  ribbon  at  the  side  may 
some  day  be  dispensed  with.  For  comfort  there  is  probably  nothing  better 
than  a  soft  felt  '  wideawake,'  but  their  crumpled  appearance  and  the  ease 
with  which  the  wind  *  takes  '  them  are  to  be  reckoned  among  their  dis- 
advantages. 

In  very  hot  weather  a  white  and  very  light  '  chimney-pot '  is  really  a 
first-rate  headdress.  A  straw  hat  of  a  light  colour  is  also  a  comfortable 
thing  in  hot  weather,  but  the  generality  of  straw  hats  are  too  low  in  the 
crown,  which  is  often  absolutely  in  contact  with  the  top  of  the  head.  A 
straw  hat  of  the  '  chimney-pot '  shape  is  comfortable,  but  not  in  favour 
among  aesthetic  people. 

A  very  important  point  in  the  choice  of  a  hat  is  its  weight,  which  should 
be  as  small  as  is  consistent  with  the  other  purposes  for  which  the  hat  is 
needed.  A  conventional  black  silk  cylinder  weighs  about  6  oz.,  and  the  com- 
mon round  felt  hat  about  as  much.  A  white  flannel  cricketing  cap  weighs 
between  two  and  three  ounces,  and  the  Grenadier's  '  bearskin  '  about  35  oz. 

There  are  a  variety  of  hats  for  special  purposes.  For  protection  against 
the  direct  rays  of  the  sun  there  is  probably  nothing  better  than  the  turban, 
its  chief  drawback  being  the  trouble  of  adjustment.  To  avoid  this  the  white 
pith  or  cork  helmet,  with  ventilating  holes  at  the  top  and  round  the  rim,  has 
been  devised,  and  is  said  to  be  a  most  efficient  protection.  A  further  protec- 
tion to  the  head  is  afforded  by  a  gauze  '  veil '  twisted  round  the  hat  and  with 
the  ends  falling  over  the  nape  of  the  neck  in  order  to  protect  the  medulla 
oblongata  from  the  direct  action  of  the  su.n's  rays.  The  Boers  of  tropical 
Africa  wear  felt  wideawakes  Avith  broad  brims,  and  the  planters  in  tropical 
America  wear  straw  hats  with  wide  brims.  If  the  brim  be  not  wide,  then  a 
veil  or  '  puggeree  '  becomes  necessary. 

The  principles  to  be  followed  in  providing  a  headdress  for  women  are 
different  because  the  true  headdress  of  women  is  the  hair,  and  any  additional 
headdress  is  only  for  the  purpose  of  keeping  the  hair  clean  and  for  adorn- 
ment. When  women  take  up  masculine  pursuits  they  usually  adopt  head- 
dresses similar  to  those  worn  by  men.  Ladies'  hats  and  bonnets  are  made 
solely  in  compliance  with  the  dictates  of  fashion,  and  there  is  no  possibihty 
of  discussing  them  with  any  advantage. 

With  regard  to  the  clothing  of  the  body  the  main  objects  are — 

1.  To  maintain  the  temperature  and  by  preventing  the  loss  of  animal 
heat  to  diminish  to  some  extent  the  demands  for  food.  Warm  clothing  is 
economical,  but  it  unfortunately  generally  happens  that  those  who  are  un- 
able to  be  warmly  clad  are  also  insufficiently  provided  with  food,  and  these 
two  evils  intensify  each  other.  '  Starved  with  the  cold  '  is  a  very  old  expres- 
sion, and  one  which  has  a  basis  of  physiological  truth,  for  if  the  body  were 
warm,  the  Avant  of  food  would  be  less  keenly  felt,  and  vice  versa. 

2.  To  allow  the  chief  heat-regulating  mechanism  (i.e.  the  evaporation 
from  the  skin)  to  proceed  with  as  little  hindrance  as  possible. 

3.  To  allow  all  muscular  acts  the  greatest  possible  freedom,  and  to 
avoid  the  compression  of  the  body  in  so  far  as  may  be  possible. 


522  HYGIENE 

4.  To  protect  the  body  from  heat,  cold,  wind,  and  rain. 

5.  To  disguise  as  little  as  may  be  the  natural  beauties  of  the  human 
figure. 

The  most  important  part  of  our  clothing  from  the  hygienic  point  of  view 
is  that  which  we  wear  next  the  skin,  the  underclothing.  The  thickness  of 
this  must  vary  with  the  season,  from  the  stoutest  flannel  to  the  thinnest 
gauze.  ^Yool  is  probably  the  best  material  for  all  seasons,  and  if  cotton  or 
linen  be  employed  it  should  be  loosely  woven,  so  that  it  may  entangle  a 
maximum,  quantity  of  air  in  its  meshes.  In  very  hot  weather  or  in  the 
tropics  a  net  is  an  excellent  form  of  under-garment.  The  '  cut '  of  under- 
clothing is  most  important,  and  the  fashion  which  has  lately  come  in  of 
making  the  under-vest  to  fasten  on  one  shoulder  is  excellent,  so  that  any 
accidental  exposure  of  the  front  of  the  chest  to  the  wind  is  thereby 
avoided. 

Underclothing  should  fit  so  as  to  follow  tolerably  closely  the  outline 
of  the  figure  without  impeding  the  movement  of  the  arm.  In  winter  it 
should  come  well  above  the  sternal  notch  and  the  sleeves  should  extend  to 
the  wrists.  It  must  not  compress  the  thorax,  abdomen,  or  arms.  A  recent 
improvement  in  underclothing  is  the  '  Combination  '  garment,  i.e.  vest  and 
drawers  in  one.  In  this  way  the  band  for  the  drawers  is  avoided  and  the 
necessity  of  compressing  the  abdomen  by  a  band  is  done  away  ^vitll,  as  is 
also  the  annoyance  of  a  double  or  even  a  treble  layer  of  material  round  the 
loins.  The  perspiration  at  this  spot  when  vigorous  exercise  is  taken  is  often 
excessive  :  the  band  of  the  drawers  gets  wet  through  and  the  risk  of  chill 
when  exercise  is  ended  is  considerable.  Another  advantage  of  this  garment 
is  the  lessening  of  the  number  of  chinks  through  which  the  wind  may  gain 
access  to  the  body.  A  most  important  matter  from  a  practical  point  of 
view  is  the  ease  with  which  garments  may  be  unbuttoned  and  adjusted  so 
as  to  obey  the  calls  of  nature  with  the  greatest  readiness,  and  in  purchasing 
'  Combination  '  garments  this  point  must  receive  attention. 

The  drawbacks  of  flannel  underclothing  are  mainly  two — viz.  the  irrita- 
tion which  they  often  cause  on  the  skin,  and  their  liability  to  shrink  when 
washed.  Some  persons  are  unable  to  tolerate  flannel  next  the  skin 
because  of  the  irritation  which  it  causes.  Such  persons  have  usually  a 
quick  circulation,  and  are  not  liable  to  chilliness  ;  but  if  great  protection 
is  necessary  wash-leather  over  silk  is  probably  the  warmest  combination 
obtainable. 

The  liability  of  flannels  to  shrhik  in  washing  is  more  serious ;  but  this 
drawback  may  be  greatly  reduced  (a)  by  '  shrinking '  the  flannel  thoroughly 
before  it  is  made  up  and  (5)  by  washing  in  cold  or  tepid  rain  water  and 
avoiding  too  much  friction  with  the  hand.  Flannel  garments  should  be 
soaped  on  both  sides  and  then  rinsed  by  waving  them  to  and  fro  in  a  large 
quantity  of  cold  soft  water.  It  is  asserted  that  in  the  tropics  there  is  no 
need  to  wash  flannel.  If  a  shirt  be  hung  up  to  dry  in  the  sun  and  thoroughly 
beaten  when  dry  it  is  said  that  its  cleansing  is  thoroughly  efl'ected  and 
that  no  foul  odour  clings  to  the  material. 

Underclothing  should  be  frequently  changed,  but  the  necessary  frequency 
must  depend  upon  the  amount  of  sweating  and  the  state  of  the  skin,  which 
differs  greatly  in  different  individuals.  If  the  skin  be  thoroughly  cleansed 
and  rubbed  every  day  a  suit  of  underclothing  may  be  worn  for  the  conven- 
tional week  without  contracting  any  animal  odour,  but  this  is  only  possible 
when  the  weather  is  cold  and  the  individual  has  taken  no  very  vigorous 
exercise  to  produce  sweating. 

In  providing  the  outer  and  visible  clothing  of  the  body  regard  must  be 


CLOTHING  523 

had  to  the  same  principles  which  guide  us  in  the  provision  of  the  under- 
clothing. The  principle  of  the  survival  of  the  fittest  would  lead  one  to 
suppose  that  there  is  not  much  amiss  with  male  clothing,  for  it  has  remained 
substantially  the  same  for  the  last  sixty  years. 

The  shirt  is  most  comfortable  when  made  of  flannel  or  some  soft  mixture 
of  wool  with  other  fibres.  A  flannel  shirt  over  woollen  underclothing  is  very 
warm  in  winter,  and  worn  alone  without  underclothing  is  the  perfection  of 
a  dress  for  the  summer. 

In  the  dirty  atmosphere  of  London  a  flannel  shirt  soon  gets  grimy  and 
looks  slovenly  and  dirty.  If,  therefore,  it  be  worn  in  town,  mild  deceptions  are 
practised  in  the  matter  of  collar  and  wristband,  and  the  front  is  concealed  with 
a  scarf.  The  highly  starched  linen  shirt,  with  its  polished  front,  collar,  and 
wristbands,  has  no  hygienic  merit  except  its  cleanly  appearance,  in  which  it  is 
unsurpassed.  There  probably  never  has  been  a  garment  so  capable  of  making 
a  man  look  clean  and  smart  at  a  comparatively  small  cost  as  the  modern  shirt. 
The  appearance  of  cleanliness  holds  the  first  place  from  an  aesthetic  point 
of  view,  and  that  which  looks  clean  and  fresh  is  sure  to  be  popular.  A 
Londoner  without  being  thought  excessively  dandified  or  extravagant  may 
have  his  two  clean  shirts  per  diem,  and  with  them  he  probably  looks  cleaner 
and  fresher  than  he  would  in  the  costly  lace  ruffles  which  were  in  vogue  in 
the  eighteenth  century. 

The  waistcoat  is  a  most  useful  and  valuable  article  of  clothing.  Origin- 
ating as  a  very  voluminous  garment — apparently  in  the  time  of  Hogarth 
(about  1738) — it  got  smaller  by  degrees  until  it  reached  its  present  very 
modest  proportions.  The  waistcoat  does  not  (or  rather  should  not)  impede 
the  movement  of  the  body  in  the  smallest  degree,  and  it  can  be  regulated 
to  suit  the  season  and  the  occupation  with  great  readiness.  Between  the 
low-cut  white  waistcoat  which  is  worn  indoors  and  the  high  sealskin 
waistcoat  lined  with  flannel  we  have  all  gradations  of  warmth,  and  there  is 
no  doubt  that  this  garment  is  of  the  greatest  jDractical  utility.  In  the 
present  day  coats  vary  immensely  in  '  cut ;  '  but  the  '  cut '  of  the  waistcoat 
scarcely  varies  at  all.  It  is  difficult  to  imagine  what  we  should  do  without 
the  waistcoat  pockets,  which  are  at  once  safe  and  convenient, 

A  '  sleeved '  waistcoat  is  a  very  warm  garment,  and  a  very  useful  one  for 
those  who  have  to  encounter  a  mixture  of  active  work  and  inactivity,  such 
as  railway  porters,  who  would  be  much  inconvenienced  by  a  coat,  and  who 
are  too  much  exposed  to  weather  to  work  'in  their  shirt-sleeves.' 

What  can  be  said  of  coats,  except  that  they  should  fit  and  allow  abso- 
lute freedom  of  movement  to  the  arms,  diaphragm,  and  abdominal  muscles 
"without  forming  creases  ? 

The  writer  is  not  one  of  those  who  is  disposed  to  cavil  at  modern  male 
attire.  In  the  main  it  is  comfortable  and  sensible,  and  it  is  very  hard  to 
beUeve  that  the  Cavalier  of  the  seventeenth  century,  in  all  the  glory  of  gold, 
velvet,  feathers,  and  curled  hair,  had  any  advantage  in  the  matter  of  appear- 
ance when  compared  with  the  spotlessly  clean  and  exquisitely  neat  gentleman 
of  the  nineteenth  century.  Ostentation  in  the  matter  of  dress  on  the  part 
of  a  man  would  at  the  present  day  merely  raise  a  laugh.  The  duke  and  his 
butler  are  both  contented  with  a  white  shirt  and  a  black  suit  of  clothes,  and 
the  fact  that  the  wealthy  are  content  with  the  same  simple  clothing  as  tbe 
comparatively  poor  may,  we  think,  be  taken  as  evidence  that  our  universally 
adopted  garments  have  reached  a  high  degree  of  perfection,  from  the  point 
of  view  of  comfort  and  suitability. 

It  is  needless  to  say  that  coats  vary  in  accordance  with  the  work  to  be 
done.     Tails  and  skirts  are  necessary  from  an  aesthetic  point  of  view,  when. 


524  HYGIENE 

with  advancing  years  the  figure  becomes  protuberant.  They  are  also  very 
useful  as  furnishing  space  for  pockets.  Tails  and  skirts  hamper  movement, 
and  do  not  materially  increase  the  warmth  of  the  garment.  One  of  the 
warmest  and  best  garments  for  winter  wear  is  the  'pilot'  jacket,  which 
buttons  up  and  affords  first-rate  protection  to  the  chest  and  abdomen,  while 
it  does  not  in  any  degree  impede  the  movement  of  the  legs. 

^\'llen  a  garment  is  worn  for  warmth  it  is  all- important  to  protect  the 
abdomen  and  chest.  If  this  be  efficiently  done  it  is  not  so  necessary  to  pro- 
tect the  limbs.  The  Highland  kilt  is  said  to  be  a  very  warm  garment, 
because  it  extends  nearly  up  to  the  level  of  the  armpits,  and  being  thickly 
pleated  it  affords  a  very  great  deal  of  protection  to  the  trunk. 

From  a  purely  hygienic  point  of  view,  however,  the  bare  Imees  of  the 
Highlander  are  as  indefensible  as  the  '  bearskin  '  of  the  Grenadier. 

For  very  cold  weather  and  for  travelling,  fur-lined  coats  are  much  used. 
The  protection  they  afford  is  enormous,  but  they  are  too  heavy  for  walking 
in.  The  same  maybe  said  of  the  modern  'ulster,'  which  is  a  warm  but 
very  cumbersome  garment. 

In  very  variable  climates,  such  as  the  south  of  Europe,  where  the  extremes 
of  temperature  are  very  wide  apart  and  the  fluctuations  sudden,  it  is  usual 
to  wear  a  cloak  loosely  hung  upon  the  shoulders,  in  order  that  the  body  may 
be  enveloped  by  it  at  a  moment's  notice  should  the  occasion  arise,  as  it  fi-e- 
quently  does,  especially  at  sunset. 

The  clothing  of  the  legs,  as  far  as  man  is  concerned,  resolves  itself  into 
a  question  of  tro2isers  or  knee-breeches. 

Trousers  have  the  great  advantage  of  compressing  the  body  at  no  point, 
and  of  allowing  the  greatest  freedom  of  movement  to  the  leg.  The  great 
freedom  of  movement  in  trousers  is  shown  by  the  fact  that  they  are  uni- 
versally worn  in  the  cricket  field,  where  the  body  is  called  upon  to  undergo 
very  sudden  changes  of  position.  Cricket  is  a  game  which  involves  the 
keenest  competition,  and  concerning  the  dress  to  be  worn  while  playing 
cricket  there  are  no  laws  or  regulations.  It  is  tolerably  certain  that  no  point, 
however  small,  which  could  give  one  side  an  advantage  over  the  other  would 
be  neglected.  The  fact,  therefore,  that  the  dress  of  cricketers  is  practically 
the  same  the  whole  world  over  is  very  important,  and  constitutes  the 
strongest  testimony  that  the  trouser  places  no  appreciable  check  upon  the 
movements  of  the  body.  In  the  cricket  field,  where  the  trousers  worn  are 
'  of  very  light  weight  and  there  is  nothing  worn  beneath  them,  a  buckle  to 
draw  them  in  over  the  hips  is  sufficient  to  keep  them  from  falling.  At  other 
times  it  is  necessary  to  support  the  trousers  with  something  more  secure, 
and  to  this  end  '  braces,'  which  pass  over  the  shoulder,  are  now  universally 
adopted.  There  is  no  doubt  that  braces  are  preferable  to  a  belt,  inasmuch 
as  they  do  not  compress  the  abdomen,  and  scarcely  interfere  at  all  mth  the 
movements  of  the  limbs. 

The  drawback  to  trousers  consists  in  their  liability  to  get  dirty  and  wet 
round  the  bottom,  and  the  tendency  of  fashionable  tailors  is  to  make  them 
decidedly  too  long.  This  fault  in  trousers  is  so  easily  met  by  turning  up  the 
ends  that  it  scarcely  deserves  mention.  Nevertheless,  trousers  might  be 
worn  shorter  than  at  present  with  obvious  advantage. 

The  old-fashioned  pantaloon,  or  trouser  which  buttoned  round  the  lower 
part  of  the  leg,  had  some  advantages,  and  when  worn  with  the  high  '  Hes- 
sian '  boot  was  an  excellent  arrangement  for  sloppy,  dirty  weather.  The 
boots  could  be  easily  removed  and  replaced  by  clean  shoes ;  but  in  spite  of 
these  advantages  the  pantaloon  had  a  short  reign,  and  it  is  certain  that  it 
hampered  the  movement  of  the  leg  more  than  the  trouser. 


CLOTHING  525 

Knee-breeches,  or  knickerbockers,  constitute  an  excellent  garment  for 
walking,  from  the  point  of  view  of  cleanliness  and  comfort.  They  involve 
compression  of  the  leg  below  the  knee  in  order  to  support  the  stocking,  and 
the  compression  is  seriously  felt  if  the  knee  be  bent  beyond  a  right  angle 
and  the  wearer  suddenly  assume  a  squatting  position. 

The  knickerbocker  and  the  pantaloon  as  compared  with  the  trouser  have 
the  obvious  disadvantage  of  possessing  more  buttons  and  fastenings,  and 
the  fact  that  the  legs  can  be  clothed  quicker  in  socks  and  trousers  than 
in  any  other  garment,  and  the  additional  fact  that  the  trousers  have  fewer 
buttons  to  come  off  than  any  other  garment,  are  practical  points  which  do 
much  to  maintain  the  popularity  of  the  trouser.  The  great  popularity  of 
the  knickerbocker  among  touring  pedestrians  is  to  be  attributed  to  the  small 
space  occupied  by  a  pair  of  stockings  in  a  knapsack  and  the  ease  with  which 
stockings  can  be  changed  when  the  journey  is  over. 

For  cycling,  knee-breeches  and  stockings  are  almost  universal.  In  this 
mode  of  progression  the  flexion  of  the  knee  is  seldom  excessive,  and  the  loose 
end  of  the  trouser  is  liable  to  hitch  in  the  mechanism  of  the  cycle.  These 
facts,  as  well  as  others,  make  them  popular  for  cycling. 

For  rowing,  which  necessitates  an  attitude  suggestive  of  the  letter  N, 
any  compression  round  the  knee  is  not  to  be  thought  of.  The  Highland 
kilt  undoubtedly  allows  great  freedom  to  the  legs,  especially  the  knee- 
joints,  and  those  who  wear  it  habitually  protest  that  it  is  not  cold.  For 
walking  through  brushwood  or  covert  of  any  kind,  both  the  skirt  of  the  kilt 
and  the  naked  knee  are  alike  objectionable. 

The  principles  which  hold  good  with  regard  to  women's  clothing  do  not 
differ  essentially  from  those  which  should  regulate  men's  attire.  Volumes 
have  been  written  on  this  subject,  but,  except  in  the  top  garment,  the  '  dress,' 
it  does  not  appear  that  women's  attire  has  altered  more  than  that  of  men. 
It  is  an  essential  part  of  all  costume  for  either  sex  that  it  should  readily 
admit  of  an  immediate  obedience  to  the  calls  of  nature,  and  the  main  cause 
of  the  difference  of  costume  in  the  two  sexes  is  the  difference  in  the  anatomy 
of  the  urethra.  This  is  a  point  which  is,  of  course,  kept  in  the  background  in 
all  popular  treatises.  We  do  not  intend  to  discuss  the  relative  advantage  of 
the  single  and  the  divided  skirt,  which  is  a  matter  which  women  must 
regulate  for  themselves.  Again,  on  the  question  of  '  stays  '  or  corsets,  there 
would  appear  to  be  room  for  two  opinions. 

There  can  be  no  doubt  that  any  undue  compression  of  the  waist  is 
thoroughly  bad  and  most  mischievous.  If  the  respiratory  and  abdominal 
muscles  be  not  free  to  act,  they  will  not  develop  properly,  and  if  the  waist 
be  'laced  in,'  the  heart,  lungs,  liver,  and  stomach  are  thrust  upwards  and  the 
intestines  forced  downwards.  Discomfort  after  meals  and  serious  dyspeptic 
troubles  must  and  do  result,  and  these  are  followed  by  anaemia.  The  com- 
monest symptom  of  dyspepsia  in  a  woman  is  pain  under  the  left  breast ;  a 
symptom  of  which  men  rai'ely  complain  ;  and  the  reason  for  this  difference  of 
symptom  of  the  same  disease  in  the  two  sexes  is  due  probably  to  the  dis- 
placement of  the  stomach  by  the  stays.  The  chief  defence  of  the  stays  is 
found  in  the  statement  that  they  are  necessary  for  the  support  of  the  petti- 
coats and  skirts.  There  can  be  no  difficulty  in  supporting  the  skirts  from 
the  shoulders,  but  fashion  steps  in  to  prevent  this  ;  and  there  can  be  no  doubt 
that  the  fashion  of  appearing  with  naked  shoulders  on  state  occasions  prevents 
the  general  adoption  of  what  seems  to  be  a  sensible  reform.  For  one  who  was 
accustomed  to  wear  braces,  or  some  substitute  for  them,  the  ordeal  of  going 
to  a  high  ceremony  without  them  would  be  most  trying.     A  lady's  full  dress. 


526  HYGIENE 

which  involves  a  hotlice  having  practically  nothing  over  the  shoulders,  must 
take  its  bearings  from  the  waist. 

The  weight  of  winter  skirts  and  petticoats,  especially  with  a  brocaded 
*  train  '  yards  long,  must  be  prodigious,  and  were  it  not  for  a  stiff  corset  firmly 
poised  upon  the  hips,  the  carriage  of  such  gear  without  shoulder-straps  would 
be  impossible. 

The  articles  of  clothing  for  the  feet — socks  and  stockings,  boots  and  shoes 
— probably  influence  our  comfort  more  than  any  other  portion  of  our  attire. 

Like  many  other  articles  of  clothing,  they  are  said  to  be  unnecessary,  and 
we  are  told  that  the  naked  human  foot  soon  gets  accustomed  to  variations  of 
temperature,  and  '  the  thousand  natural  shocks '  which  are  inseparable  from 
labour  and  locomotion. 

Be  this  as  it  may,  it  has  been  the  custom  of  all  civilised  races  from  re- 
motest periods  to  clothe  the  foot,  and  there  is  no  probability  that  this  custom 
will  be  departed  from. 

In  considering  this  subject  we  must  deal  with  it  in  the  first  instance  in 
relation  to  utility,  i.e.  to  foot-coverings,  in  which  a  man  can  work  or  take 
vigorous  and  active  exercise.  As  to  '  dress  '  boots  and  shoes,  articles  which 
are  worn  mainly  for  decency  or  adornment,  and  in  compliance  with  the  dic- 
tates of  custom,  that  is  another  matter  upon  which  one  may  treat  lightly. 

In  considering  '  foot-coverings  '  we  must  remember  that  the  boot  is  only 
the  outer  covering  of  the  foot,  and  that  within  it  is  the  stocking  or  sock. 
With  regard  to  the  stocking  or  sock,  this  should  always  be  of  a  woollen  mate- 
rial, or  of  a  mixed  material  in  which  wool  predominates.  The  hygroscopic 
qualities  of  wool  cause  it  to  absorb  the  perspiration  of  the  foot,  and  its  elasticity 
as  a  woven  fabric  and  its  power  of  stretching  make  it  less  liable  to  form  creases 
and  to  give  rise  to  the  consequence  of  creases,  i.e.  blisters  and  corns.  A  sock 
should  '  fit,'  i.e.  it  should  have  in  its  material  neither  poverty  nor  riches  ;  it 
should  not  cramp  the  foot,  and  should  form  neither  folds  nor  creases.  Its 
substance  must  vary  with  the  time  of  year,  the  work  to  be  done  with  the  foot, 
the  kind  of  boot  to  be  worn,  and  the  fancy  of  the  owner.  A  sock  should  be 
without  any  projecting  seams.  Eibbed  stockings  or  socks  are  comfortable, 
and  allow  some  slight  circulation  of  air  between  the  sock  and  the  boot. 
Socks  may  be  made  '  right  '  and  '  left,'  and  when  thus  made  they  undoubtedly 
fit  more  accurately ;  but  this  is  perhaps  an  unnecessary  refinement,  as  there 
is  always  room  to  spare  in  the  toe  of  a  sensibly  made  boot  above  the  fourth 
and  fifth  toes,  and  if  there  be  a  little  redundancy  of  fabric  at  this  point  it 
causes  no  inconvenience.  When  very  thick  winter  socks  are  worn  it  may  be 
an  advantage  to  have  them  '  right '  and  '  left.' 

A  greater  refinement  than  having  the  socks  right  and  left  is  to  have 
them  digitated,  with  compartments  for  each  toe.  This  may  be  necessary  for 
those  who  have  pathological  conditions  of  the  feet,  such  as  soft  corns  between 
the  toes,  or  an  inordinate  tendency  to  perspiration  between  the  toes.  If 
socks  be  digitated,  then  accuracy  of  fit  becomes  doubly  necessary.  Again,  a 
woollen  digitated  sock  would  probably  not  be  very  comfortable  after  a  few 
washings  and  darnings. 

There  are  those  who  maintain  that  even  if  boots  be  worn  socks  and 
stockings  are  unnecessary.  If  socks  be  not  worn  the  boots  must  be  very  well 
made  and  perfectly  free  from  projecting  internal  seams  or  anything  else  likely 
to  rub  against  the  foot.  If  the  boot  be  suitably  made  of  supple  leather,  and 
if  the  foot  and  boot  be  greased  internally,  it  is  probable  that  walking  may 
be  accomplished  with  great  comfort,  and  if  the  boot  be  kept  clean  inside  as 
well  as  out  (i.e.  if  a  filthy,  blacking-bedaubed  hand  be  not  inserted  into  it  for 


CLOTHING  .  527 

cleaning,  as  too  often  is  the  case),  the  foot  will  wash  perfectly  clean,  and  no 
staining  or  galling  will  result.  If  no  socks  be  worn,  it  follows  that  the  boot 
may  be  slightly  smaller  and  lighter,  which  is  an  advantage  during  a  long 
walk  ;  but  when  the  pedestrian  halts,  especially  if  he  halts  in  a  cold  place, 
such  as  a  mountain  top,  the  feet  are  apt  to  chill,  because  leather  is  a  good 
conductor  of  heat.  If,  however,  the  pedestrian  is  not  going  to  incur  any 
such  risks,  and  can  change  to  a  pair  of  socks  and  shoes  when  the  walk  is 
over,  it  is  probable  that  there  are  many  advantages  in  having  no  socks  or 
stockings.  For  this  practice  to  be  successful,  the  boots  must  be  first-rate  and 
must  fit  accurately.  When  pedestrians  wear  roughly-  and  ready-made  boots, 
as  is  the  case  with  soldiers,  a  sock  is  absolutely  necessary,  and  it  is  said  that 
those  who  wear  no  socks  are  in  the  habit  of  wrapping  a  piece  of  linen  round 
the  toes  to  preserve  them  from  bruising. 

If  no  socks  be  worn  the  boot  must  be  rather  high  in  the  upper,  and  must 
fit  well  round  the  ankle,  so  as  to  prevent  dust  or  small  stones  finding  an 
entrance  to  the  boot. 

For  indoor  wear  upon  carpets  there  is  no  objection  to  socks  of  linen, 
cotton,  silk,  or  any  material  which  the  wearer  fancies,  provided  he  be  not 
liable  to  cold  feet,  in  which  case  '  merino  '  is  probably  the  best  material. 
Cold  feet  are  to  be  avoided,  especially  at  night,  as  if  the  feet  get  chilled  there 
is  apt  to  be  an  undue  supply  of  blood  to  the  head,  and  sleeplessness  very 
■commonly  results.  As  to  the  colour  of  socks,  the  wearer  may  follow  his  fancy 
provided  they  be  properly  dyed.  Some  years  ago  there  were  reported  cases 
of  eczema  of  the  legs  which  resulted  from  wearing  '  magenta '  socks  dyed 
Avith  an  aniline  product.  In  this  instance  the  real  cause  of  the  eczema  was 
the  employment  of  an  arsenical  compound  as  well  as  the  aniline  compound 
in  the  process  of  dyeing. 

When  stockings  are  worn  the  question  of  '  garters '  or  some  substitute 
has  to  be  considered.  Any  compressing  band  round  the  leg  is  very  un- 
desirable, and  it  is  advisable,  especially  for  children  and  growing  persons,  to 
use  '  suspenders  '  for  the  stockings  rather  than  garters.  If  garters  be  worn, 
there  is  nothing  better  than  the  old-fashioned  knitted  garter,  which  is  a  very 
good  compromise  between  the  requisite  elasticity  and  firmness.  Garters 
must  be  worn  below  the  knee,  as,  if  they  be  placed  above  the  knee,  any  strong 
contractions  of  that  joint  must  work  the  stocking  from  beneath  the  garter, 
and  the  garter,  when  worn  above  the  knee,  must  be  drawn  inordinately  tight 
in  order  to  prevent  such  a  mishap. 

Next  as  to  boots,  the  best  material  is  probably  that  which  has  been 
mainly  used  for  centuries,  viz.  leather.  Good  leather  is  very  pliable,  and  is 
hygroscopic  and  absorbent,  so  that  perspiration  is  absorbed  and  slowly  given 
off  again.  Leather,  too,  is  very  durable,  and  nothing  wears  better  for  the  sole 
of  a  boot  than  old-fashioned  English  oak-tanned  leather,  although  it  is 
doubtful  if  the  same  thing  can  be  said  for  some  of  the  chemically  prepared 
substitutes  for  that  article.  Leather  is  sufficiently  waterproof  for  most 
purposes,  and  a  stout,  well-made  boot,  especially  if  it  be  greased,  will  keep 
out  anything  but  very  excessive  amounts  of  moisture. 

Impermeable  materials  are  very  undesirable  for  boots,  and  no  one  who 
has  tried  to  walk  long  distances  in  '  patent  leather '  boots  would  wish  to 
repeat  the  experiment.  In  all  cases  the  perspiration  absorbed  by  the  inside 
of  the  boot  must  be  able  to  be  given  off  again  from  the  outside. 

India-rubber  is  a  very  undesirable  material,  especially  for  the  uppers, 
although  there  is  no  objection  to  it  for  purposes  other  than  walking,  such  as 
standing  in  water  for  fishing,  &c.,  and  for  wearing  on  board  ship  when  the 
decks  are  wet. 


628  HYGIENE 

The  writer  was  lately  consulted  by  a  gentleman  who  was  troubled  by 
swelling  of  the  feet,  and  as  there  was  no  kidney  disease,  or  heart  disease,  or 
any  detectable  cause  for  local  obstruction  to  the  circulation,  the  cause  of  the 
swelling  was  for  a  time  a  mystery.  On  questioning  him  it  turned  out  that  he 
had  been  for  some  time  in  the  habit  of  walking  about  his  farm  in  '  deck 
boots,'  that  is,  boots  made  of  india-rubber  lined  with  green  baize,  and  this 
was  the  probable  cause  of  his  trouble,  the  feet  and  legs  having  been  practi- 
cally poulticed  by  his  hot,  impermeable  boots  for  many  hours  daily.  These 
boots  were  discarded  and  the  swelling  disappeared. 

Coarse  canvas  is  now  very  often  used  for  the  uppers  of  lawn  tennis 
shoes,  and  there  is  no  objection  to  this,  but  canvas  is  unsuitable  for  boots 
meant  for  hard  wear,  as  it  does  not  resist  moisture  sufficiently. 

The  soles  of  boots  are  not  unfrequently  made  of  india-rubber  or  gutta- 
percha, and  although  the  objections  to  the  use  of  the  material  are  not  so 
great  as  when  the  uppers  also  are  made  of  it,  it  is  probably  inferior  for  soles 
to  the  time-honoured  leather. 

Volumes  have  probably  been  written  on  the  proper  shape  for  boots,  but 
when  it  is  said  that  a  boot  should  fit  the  foot  accurately  what  more  can  be 
said  ?  The  shape  of  the  sole  of  a  boot  should  be  taken  by  drawing  a  pencil 
round  the  outline  of  the  foot,  when  the  bootmaker's  '  patient '  is  standing  up, 
so  that  the  sole  may  be  big  enough  to  support  the  fully  expanded  foot.  That 
the  line  of  the  first  metatarsal  bone  and  the  phalanges  of  the  big  toe  should 
be  straight  goes  without  saying.  When  we  say  that  a  boot  should  fit,  we 
mean  that,  without  being  loose,  the  foot  should  have  room  to  move  in  it,  and 
on  putting  on  a  new  pair  of  boots  the  wearer  ought  to  be  able  to  move  all 
his  toes  with  freedom.  Not  only  should  the  lower  part  of  the  boot  fit,  but 
the  upper  part  also.  This  often  is  not  the  case,  for  even  in  what  are  called 
'  bespoke '  articles  the  upper  is  not  unfrequently  '  ready-made,'  and  is  merely 
the  nearest  approach  to  a  fit  which  the  bootmaker  could  procure.  It  is  un- 
doubtedly true  that  '  ready-made  '  boots  may  fit  accurately,  but  it  is  only  a 
happy  chance  if  they  do  so,  and  seeing  that  the  contour  of  the  foot  is  not 
precisely  the  same  in  any  two  individuals,  it  follows  that  if  a  man  have  tender 
feet  his  best  course  is  to  go  to  a  first-rate  bootmaker  and  have  the  boot  made 
for  him  throughout.  Keady-made  boots  have  this  fault,  that  the  unintelligent 
steam  machinery  which  turns  them  out  does  not  consider  the  endless  varie- 
ties in  shape  which  the  human  foot  presents. 

Boots  which  do  not  fit  cause  deformities  of  the  feet,  and  especially  in  early 
life.  Among  the  Scotch  and  Irish  peasantry  the  children  of  quite  respectable 
parents  wear  no  boots,  and  this  causes  a  proper  development  of  the  foot 
during  the  periods  of  active  growth,  and  the  feet  are  free  from  corns  or 
bunions,  and  the  liability  to  chilblains  is  probably  less  if  the  children  be  well 
nourished.  Undoubtedly  when  such  children  have  to  adopt  boots  they  pass 
through  some  discomfort,  but  their  chance  of  being  properly  fitted  and  not 
pinched  is  probably  greater  than  among  those  children  whose  feet  have 
become  deformed  by  improper  boots. 

Boots  are  a  great  expense  to  the  poor,  for  it  is  doubtful  whether  children 
grow  out  of  their  boots  or  wear  them  out  the  more  quickly.  This  often 
results  in  their  being  provided  from  economical  reasons  with  boots  which  are 
too  heavy  and  too  big,  and  thus  their  exercise  is  often  hampered  and  their 
feet  often  bruised. 

Children  should,  if  they  wear  boots,  have  them  renewed,  not  only  in  ac- 
cordance with  the  wear  of  the  boot,  but  also  with  the  growth  of  the  child.  If 
this  be  not  done  the  foot  gets  compressed  and  distorted,  and  the  toes  have 
a  tendency  to  overlap,  and  chilblains  are  common.     Growth  does  not  stop 


CLOTHING  529 

much,  if  at  all,  before  twenty  years  of  age,  and  sometimes  continues  after  that 
period,  so  that  young  ladies  and  youths  should  have  great  attention  paid  to 
their  boots  in  order  to  prevent  troubles  which  may  last  them  through  life. 

From  some  points  of  view  shoes  are  better  than  boots,  as  the  latter  are 
liable  to  compress  the  muscles  and  tendons  in  the  neighbourhood  of  the 
ankle,  and  so  weaken  them  and  prevent  their  proper  development.  The  cause 
of  '  weak  ankles '  is  to  be  found  as  often  as  not  in  an  unwise  compression  of 
that  region,  and  although  a  firmly  laced,  well-fitting  ankle  boot  undoubtedly 
supports  the  ankle,  it  also  prevents  the  ankle  from  learning,  so  to  say,  to 
support  itself.  Shoes  have  the  disadvantage  of  allowing  sand  and  dirt  to  get 
in  over  the  upper  edge,  and  there  is  no  doubt  that  when  shoes  are  worn  the 
socks  are  dirtier  after  a  long  walk  than  when  ankle  boots  are  worn.  When 
shoes  are  worn  for  heavy  work  some  sort  of  gaiter  is  necessary,  but  this  intro- 
duces a  complication  into  dress  which  occupies  time  in  cleaning  and  putting 
on  and  off,  so  that,  all  things  considered,  it  is  probable  that  ankle  boots,  which 
are  now  so  generally  worn,  are  for  ordinary  purposes  the  best.  We  are 
seldom  wrong  in  concluding  that  that  which  is  generally  worn,  and  is  not 
worn  merely  in  obedience  to  a  caprice  of  fashion,  has  some  very  solid  and 
practical  merits. 

For  hard  walking,  high  boots  such  as  come  up  to  or  approach  the  knee 
are  too  hot,  but  for  slow  walking,  such  as  partridge  shooting  in  wet  turnips, 
the  high  boot  which  laces  up  the  middle,  and  which  is  really  a  boot  and  gaiter 
in  one,  has  undoubted  merits. 

The  so-called  '  Wellington  '  boot  or  '  half  Wellington  '  with  a  high  upper, 
and  which  has  no  fastenings,  but  merely  slips  on  and  off,  has  great  advantages 
in  the  fact  that  the  wearer  is  never  the  victim  of  broken  laces  or  absent 
buttons.  Their  drawback  is  the  heat  of  them  and  the  fact  that  unless  they 
be  unduly  loose  they  are  apt  to  be  very  difficult  to  get  on  and  off  after  a 
prolonged  soaking  in  wet  ground.  The  German  Army  boot  is,  it  is  right  ta 
say,  of  this  pattern. 

The  sole  of  a  boot  should  be  wider  than  the  foot,  and  if  the  boot  is  to  be 
used  for  heavy  walking  this  excess  of  breadth  in  the  sole  should  be  consider- 
able, so  as  to  serve  as  a  protection  from  rocks  and  loose  stones.  The  thick- 
ness of  the  sole  must  vary  according  to  the  work  to  be  done.  In  a  variable 
climate  like  ours  it  is  always  advisable  to  wear  soles  of  some  substance,  just 
on  the  same  principle  that  it  is  wise  to  be  provided  with  an  umbrella  even  if 
the  sun  be  shining.  The  thicker  the  sole,  the  less  phant  it  is,  and  a  rigid 
sole  is  bound  to  wear  out,  at  the  toe  especially,  for  in  walking  the  heel  is 
first  placed  on  the  ground  and  the  last  act  is  the  final  push  against  the 
ground  with  the  point  of  the  big  toe,  and  if  the  sole  be  too  thick  to  bend  the 
toe  must  get  worn  out  long  before  the  sole  at  large.  The  outside  of  the  heel 
and  the  inside  of  the  toe  are  the  two  normal  points  of  main  wear  in  a  boot, 
the  centre  of  the  sole  (slightly  on  the  outside)  being  the  third  point.  Man 
shows  his  descent  from  the  ape  by  walking  slightly  on  the  outer  side  of  his 
feet.  Thick  or  '  clump-soled  '  boots  are  generally  made  thin  in  the  waist  from 
the  mistaken  notion  that  this  gives  pliancy  to  the  sole.  As  a  matter  of  fact, 
the  waist  of  a  boot  has  no  tendency  to  bend  at  all,  the  line  of  bending  being 
further  forward  exactly  beneath  the  crease  which  forms  on  the  top  of  a  boot 
which  has  been  worn,  that  is^  a  line  extending  obliquely  from  the  metatarso- 
phalangeal joint  of  the  big  toe  to  the  corresponding  point  of  the  little  toe. 
Boots  have  been  made  with  a  sort  of  hinge  in  the  sole  taking  the  course  of 
this  line,  but  as  the  strength  of  a  sole  is  to  be  measured  by  the  strength  of 
its  weakest  point,  and  as  the  '  hinge  '  is  necessarily  a  weak  point  into  which 
moisture  and  grit  are  liable  to  find  their  way,  it  is  doubtful  if  this  plan  is 

VOL.    I.  M  il 


530  HYGIENE 

practically  of  much  use.  The  wear  and  resisting  power  of  a  sole  is  to  be 
measured  more  by  the  thickness  of  the  individual  layers  of  leather  than  the 
thickness  of  the  sole  as  a  whole.  For  a  sole  may  be  very  thick  and  yet  be  made 
mainly  of  rubbish.  The  middle  layer  of  the  three  which  form  the  sole  of  an 
ordinary  '  double  '  (i.e.  really  treble)  soled  boot  is  often  of  inferior  quality,  and 
directly  the  outer  layer  gets  worn  the  middle  layer  readily  absorbs  moisture. 
A  stout  single  sole  (i.e.  a  sole  of  two  layers)  is  a  better  protection  than  one 
of  three  thinner  layers,  and  has  the  advantage  of  being  lighter.  It  is  doubtful 
if  for  heavy  work  a  moderately  heavy  boot  is  any  disadvantage.  An  ordinary 
pair  of  walking  boots  weigh  about  two  pounds,  a  thick  pair  nearly  three,  and 
a  pair  of  very  heavy  shooting-boots  with  nails  weigh  about  three  and  a  half 
pounds.  This  weight  is  nothing  for  the  legs  of  a  moderately  active  anan,  and 
if  the  ground  to  be  traversed  is  rough  a  pair  of  big  boots  is  a  great  advan- 
tage, especially  in  coming  downhill.  Professional  walkers  and  professional 
mountaineers  all  adopt  heavy  boots.  It  may  be  well  to  remark  that  big  hob- 
nails have  certain  advantages,  of  which  the  increased  '  wearing  '  power  is  only 
one.  They  give  a  very  firm  hold  of  the  ground  and  are  very  necessary  for 
mountaineering,  and  especially  on  slippery  grass  slopes.  They  are  the  only 
things  which  hold  satisfactorily  to  a  '  greasy  '  pavement.  They  raise  the 
sole  of  the  boot  off  the  ground  and  help  very  materially  to  keep  the  foot  warm 
and  dry,  and  further  they  are  very  clean  ;  and  in  walking  on  sloppy  ground 
(such  as  a  pavement  during  a  thaw),  they  splash  very  little.  They  should 
always  be  worn  by  those  who  are  obliged  to  be  out  in  all  weathers,  such  as 
soldiers,  policemen,  postmen,  &c.  To  obtain  these  results  only  a  very  few  nails 
are  necessary,  but  they  must  not  be  too  few,  because  if  the  points  of  pressure 
of  the  nails  are  not  sufficiently  close  they  are  apt  to  make  their  pressure  felt 
upon  the  foot  itself  and  cause  sores  or  corns.  Again,  if  the  nails  be  too  far 
apart  to  give  each  other  some  mutual  support  they  are  sure  to  kick  out. 
Nails  are  now  made  with  projections  in  the  head  which  stick  into  the  sole, 
and  such  nails  are  very  firm.  The  plan  of  inserting  nails  in  groups  of  three, 
so  that  each  nail  is  supported  by  the  other  two,  is  also  a  very  good  one. 
ScreAV  nails,  again,  are  absolutely  firm,  but  necessitate  a  great  thickness  of 
leather  to  hold  the  screw. 

The  heels  of  boots  have  been  much  written  about,  and  it  is  tolerably  certain 
that  they  are  no  help  to  progression,  and  from  the  purely  physiological  point 
of  view  are  useless.  The  heel  of  a  boot  is  the  first  point  to  wear  out  whether 
the  heel  be  raised  or  not,  and  as  the  ordinary  raised  heels  are  very  easily 
repaired  they  are  economical,  and  it  is  probably  due  to  this  fact  that  the 
fashion  of  '  heels  '  has  lasted  for  centuries.  They  serve  also  to  keep  the  foot 
off'  the  ground  and  help  to  keep  it  dry,  and  they  also  probably  serve  to  pre- 
vent splashing,  which  is  a  very  legitimate  aesthetic  and  practical  consideration. 
The  heels  of  boots  should  most  certainly  be  low  and  broad,  and  a  high  taper- 
ing heel  which  lessens  the  basis  of  support  for  the  body  is  absolutely  indefen- 
sible. The  inordinately  high  heels  which  are  worn  by  some  ladies,  by  raising 
the  hind  part  of  the  foot,  diminish  its  apparent  length,  and  this  undoubtedly 
is  the  cause  of  the  persistence  of  this  fashion.  It  is  needless  to  say  that 
they  cause  the  foot  to  look  deformed  and  make  active  locomotion  impossible 
by  effectually  taking  away  the  power  of  '  spring  '  from  the  foot,  and  by  throw- 
ing undue  pressm'e  on  to  the  unfortunate  toes  which  are  crowded  together  in 
this  irrational  foot-gear.  High  heels  increase  the  apparent  height  of  the 
individual  and  they  apparently  are  much  admired  by  men,  which  probably 
accounts  for  their  almost  universal  use  upon  the  stage  and  in  other  public 
places. 

It  needs  hardly  to  be  said  that  dancing  in  any  true  sense  is  impossible 


CLOTHING  531 

in  high-lieeled  shoes.  The  last  of  the  famous  dancers  who  really  dis- 
played the  true  poetry  of  motion  was  probably  Madame  Taglioni,  and  it  is 
perhaps  worth  recording  that  this  lady  always  wore  a  pair  of  simple  absolutely 
pliant  satin  slippers  without  heels  of  any  kind,  and  fastened  by  slender  elastic 
bands.  The  modern  ballet  shoe  has  an  absolutely  rigid  toe,  so  as  to  enable 
the  danseiise  to  perform  the  pas  cles  pointes,  which  seems  to  be  the  sine  qud 
non  of  modern  stage  dancing,  which,  whatever  may  be  its  merits,  most 
certainly  is  not  dancing. 

If  the  object  of  foot-gear  be  mainly  to  keep  the  foot  warm,  tbon  un- 
doubtedly woollen  materials  or  fur  linings  are  advisable. 

The  Chinese  shoe,  which  is  admirable  in  this  respect,  has  a  sole  about 
an  inch  thick,  made  of  layers  of  thick  paper  or  felt,  and  by  this  means  the 
Chinaman,  who  seldom,  indulges  in  very  active  exercise,  and  who  never 
employs  carpets  in  his  house,  is  enabled  to  keep  the  foot  comfortably  warm, 
even  in  the  depth  of  winter.  Slippers  made  of  felt  are  admirable  for  keeping 
the  feet  warm  indoors,  as  is  also  the  slipper  with  a  hempen  sole,  which  is  so 
largely  worn  in  the  Basque  Provinces  and  elsewhere  in  the  south  of  Europe. 
A  cloth  or  woollen  top  to  ihe  boot  is  a  most  comfortable  arrangement  for 
winter. 

The  wooden  shoe,  or  sabot,  and  the  Lancashire  clog,  which  is  a  sabot  shod 
with  iron,  is  a  very  cheap  and  serviceable  foot-gear  for  working  in  sloppy 
places,  and  it  has  the  advantage  of  being  put  on  and  off  in  a  moment.  The 
old-fashioned  patten,  which  used  to  be  so  much  worn  by  women  engaged  in 
sloppy  work,  is  also  a  very  admirable  and  simple  contrivance  for  keeping  the 
feet  dry  under  certain  conditions. 

The  American  overshoe  and  the  '  golosh '  need  only  to  be  mentioned  as 
very  useful  things  for  temporary  purposes,  but  quite  useless  when  rapid  or 
prolonged  locomotion  is  required. 

Before  leaving  the  subject  of  foot-gear,  it  may  be  mentioned  that  it  is 
very  advisable,  and  especially  for  delicate  persons,  to  be  careful  to  change  the 
shoes  and  stockings  after  active  exercise,  as  the  cold  produced  by  the 
evaporation  of  the  perspiration  is  very  liable  to  chill  the  feet.  If  the  feet 
get  wet  in  the  course  of  exercise  it  need  hardly  be  said  that  this  precaution 
is  doubly  necessary.  There  is  little  danger  in  getting  wet  feet  or  in  being 
wet  through  provided  the  pedestrian  keeps  moving,  but  if  he  neglect  to 
change  his  clothing  immediately  his  exercise  ceases  he  is  sure  to  get  '  a 
chill.' 

Our  remarks  hitherto  have  been  solely  directed  to  working  boots,  but 
perhaps  in  a  subject  of  so  much  importance  it  may  be  permitted  to  say  a 
few  words  on  the  aesthetic  side  of  the  subject,  and  be  it  remembered  that 
trained  esthetic  faculties  are  the  true  aids  of  the  hygienist,  because  the  first 
canon  of  assthetic  law  with  regard  to  clothing  must  be  cleanliness.  No 
article  of  clothing  which  is  not  clean  can  possibly  please  the  eye,  and  there- 
fore the  first  consideration  with  regard  to  boots  is  facility  for  cleaning. 
As  the  English  stand  almost  alone  among  European  nations  in  the  art  of 
boot  cleaning,  it  is  to  be  presumed  that  our  common  methods  in  that  respect 
are  sound ;  and  indeed  it  is  hard  to  imagine  anything  more  satisfactory  to 
the  eye  than  a  black  leather  boot  thoroughly  pohshed  with  'blacking,' 
which  is  a  carbonaceous  mixture,  the  fine  particles  of  which  can  be  made 
to  shine  by  brushing. 

A  material  which  makes  a  boot  appear  clean  and  brilliant  without  inter- 
fering with  its  porosity  or  pliancy  has  qualities  which  are  of  great  value, 
and  if  it  had  not  the  disagreeable  property  of  soiling  the  hands  and  clothing 
which  come  in  contact  with  the  boot,   its  popularity  would  be  assuredly 


532  HYGIENE 

permanent.  Xo  varnishes  can  be  regarded  as  in  any  sense  a  substitute  for 
blacking,  for  in  the  first  place  they  destroy  the  porosity  of  the  leather,  and 
in  the  second  place  the  application  of  layer  upon  layer  makes  the  surface 
of  the  leather  uneven,  and  suggests  filthiness  rather  than  cleanliness. 
Varnishes  do  not  soil  the  hands,  "which  is  some  advantage. 

Bootmakers  do  not  sufficiently  consider  the  comfort  of  the  wearer  in  small 
matters.  Why  should  new  boot-laces  be  soaked  in  carbon  and  grease  up  to 
their  very  ends  ?  Why  should  not  that  part  of  a  lace  which  is  touched  by 
the  hand  be  left  free  from  soiling  impurities  ? 

There  is,  just  now,  a  fashion  for  boots  made  of  brown  and  '  tan  '  leathers,, 
a  fashion  which  had  its  origin  among  military  men  engaged  in  tropical  cam- 
paigns. The  light  tint  of  these  leathers  make  them  cool  for  the  feet,  and 
this  fact,  combined  with  cleanliness,  has  done  much  to  make  them  popular. 
From  an  a;sthetic  point  of  view  they  appear  to  be  surpassed  by  polished 
black,  which  gives  to  even  an  old  boot  an  appearance  of  absolute  cleanliness, 
which  the  tan  leather  never  has,  and  least  of  all  when  old  and  stained. 
Nothing  makes  the  outline  of  a  foot  appear  so  small  to  the  eye  as  when  it  is 
clothed  in  black,  with  a  polished  surface  which  reflects  the  light. 

A  boot  to  look  well  should  show  the  outline,  and  should  not  conceal  the 
movement  of  the  foot,  which  is  one  of  its  chief  beauties.  The  beauty  of  a 
foot  consists,  not  only  in  its  outline,  but  in  its  elastic  pliancy  and  its  proper 
proportion  to  the  rest  of  the  body.  '  Small  feet '  are  considered  a  beauty, 
but  there  can  be  no  doubt  that  a  foot  should  bear  a  due  proportion  to  the 
body.  A  man  with  inordinately  small  feet  is  apt  to  have  an  appearance  of 
eflt'eminacy  and  feebleness,  which  is  not  pleasing  to  any  healthy  esthetic 
sense  ;  and  when  we  see  a  man  with  his  feet  crammed  into  tight  high-heeled 
boots,  so  that  he  is  compelled  to  '  strut,'  instead  of  walk,  it  is  hardly  pos- 
sible for  our  '  first  impression  '  not  to  be  one  of  slight  contempt. 

As  boots  and  shoes  necessarily  add  to  the  apparent  size  of  the  foot,  it  is- 
very  important  that  nothing  in  their  design  should  unduly  add  to  this 
aesthetic  drawback.  To  this  end  foot-gear  should  be  uniform  in  colour.  A 
mixture  of  tints  and  elaborate  patterns  (checks,  &c.)  undoubtedly  make  the 
foot  look  large,  as  do  also  big  bows  and  rosettes. 

The  weight  of  clothing  is  considerable,  but  necessarily  varies  with  the 
season  of  the  year.  The  following  are  the  weights  of  the  ordinary  civil 
attire  of  a  man  weighing  133  lb.,  and  5  feet  6h  inches  in  height : — 

Lb.  oz.  Lb.  oz. 

Socks .         .     from  0  1^-  to  0  4 

Under-vests „  0  3i  „  0  13^ 

Under-drawers „  0  4|  „  0  12| 

Shirts ,  0  9J  „  0  is" 

Trousers „  0  15  „  2  2 

Waistcoat „  0  7  „  0  121 

Coat „  2  5i  „  3  1 

Boots „  1  7"  „  3  0 

CoUar „  0  OJ  „  0  0| 

Handkerchief „  0  1^-  „  0       1^ 

Cravat „  0  l"  „  0       2 

Total  weight  of  clothes     .69  11     14| 

Thus  it  is  seen  that  the  weight  of  clothes  which  may  be  worn  in  summer 
and  winter  varies  considerably. 

When  out  of  doors  there  are  considerable  additions  to  be  made,, 
thus  : — 


CLOTHING 

Lb.    oz.  tM. 

Hat from     0      2      to     0      7 

Scarf 

Gloves         

Overcoat      ....... 

Umbrella     ....... 

Keys,  money,  watch,  &c 


0  0  „  0  3 

0  o:i  „  0  4 

2  12i-  „  B  0 

i  i!  „  1  i| 

2  10  „  2  10 


Total  extras     .     6     11  12      9J 

Thus  it  appears  that  a  man  in  walking  attire  in  the  winter  may  liave  to 
•carry  as  much  as  24  lb.  8^  oz.,  or  rather  more  than  18  per  cent,  of  tlie  weight 
of  his  body.  Of  this  weight  only  7  oz.  is  carried  on  the  head,  and  3  lb.  4  oz. 
•on  the  feet,  while  2  lb.  14|  oz.  are  suspended  from  the  shoulders  and  partly 
supported  by  the  hips ;  while  of  the  remainder  16  lb.  9^  oz.  are  carried 
entirely  on  the  shoulders  and  1  lb.  5|  oz.  are  carried  by  the  hands. 

There  can  be  httle  doubt  that  the  shoulders  are  best  able  to  carry  the 
maximum  weight,  and  the  writer  is  not  prepared  to  offer  any  adverse  criticism 
.to  the  distribution  of  the  weight  of  the  clothing  given  above.  The  pedes- 
trian often  has  to  carry  a  knapsack,  and  the  problem  of  how  best  to  distri- 
bute the  weight  arises.  Heavy  weights  are  carried  after  a  little  practice  on 
the  head  with  great  ease,  and  it  is  probable  that  the  carrying  of  weights  upon 
the  head  is  a  sure  way  of  producing  an  upright  carriage  and  graceful  figure. 
If  the  weight  be  divided  between  the  head  and  shoulders  by  means  of  an 
apparatus  which  may  be  seen  any  day  in  Covent  Garden  Market,  very  heavy 
burdens  may  be  carried  with  comparative  ease.  Such  methods  are,  however, 
impracticable  for  the  traveller,  and  the  shoulders  and  hips  are  the  points 
upon  which  a  knapsack  is  best  supported.  The  old  fashion  of  carrying  the 
military  knapsack  entirely  upon  the  shoulder  and  fixing  it  by  cross-belts  over 
the  chest,  undoubtedly  compressed  the  thorax,  hampered  the  breathing,  and 
produced  irritation  of  the  heart. 

Straps  passing  from  the  top  of  the  knapsack  over  the  shoulders  and  then 
xeturning  to  the  bottom  of  the  knapsack  by  bending  round  the  armpits  are 
found  to  be  practically  serviceable,  and  they  keep  the  knapsack  steady  both 
for  quick  and  slow  time  of  march  and  in  going  up  or  down  hill. 

A  very  excellent  form  of  knapsack  is  one  consisting  of  two  bags,  of  which 
one  lies  against  the  upper  dorsal  region,  and  the  other  in  the  hollow  of  the 
loins.  They  are  united  by  straps  passing  from  the  top  of  the  upper  bag  over 
the  shoulders  and  then  obliquely  downwards  in  the  axillary  region  to  the 
top  of  the  second  bag.  These  bags  are  then  supported  partly  on  the  shoulders 
and  partly  on  the  sacrum,  and  as  one  bag  balances  the  other  the  weight  is 
well  divided.  The  only  drawback  is  their  tendency  to  bump  about  when  the 
traveller  is  coming  downhill,  a  tendency  which  is  easUy  checked  by  stays 
passing  to  a  waist-belt. 

A  few  words  may  be  said  with  advantage  on  the  aesthetic  aspects  of  dress, 
although  it  is  true  that  there  is  no  possibility  of  disputing  about  matters  of 
taste.  There  seem  to  be  some  few  principles,  however,  which  form  the  true 
groundwork  of  the  question,  which  it  may  be  well  to  discuss. 

In  the  first  place  a  dress  must  suggest  cleanliness  and  purity,  if  we 
place  side  by  side  in  the  mind's  eye  the  modern  nurse  or  dairymaid  in  clean 
print  dress  and  spotless  cap  and  apron  and  the  costermonger's  girl  bedecked 
in  tawdry  finery,  there  can  be  no  question  as  to  which  is  most  pleasing  to  the 
educated  eye.  No  costume  can  really  look  weU  if  it  be  not  kept  clean,  and 
directly  a  dress  suggests  anything  but  the  most  perfect  cleanliness  its  aBsthetic 
•value  becomes  nil. 

The  working  classes  in  this  country  dress  very  largely  in  the  cast-off 


534  HYGIENE 

clothing  of  the  class  above  them,  and  persons  who  are  too  poor  to  keep  a 
lady's  maid  are  fond  of  imitating  the  costumes  of  those  who  do,  with  the 
result  that  such  costumes  are  never  properly  cleaned  and  brushed ;  an  opera- 
tion which  the  owner,  who  probably  has  many  duties,  has  not  time  to  perform. 
The  working  classes  in  this  country  seldom  wear  a  blouse,  as  the  French  do, 
and  the  smock  frock  has  been  almost  completely  abandoned,  with  the  result 
that  a  large  proportion  of  the  labouring  classes  look  habitually  filthy.  It  is 
absolutely  essential  from  the  {esthetic  and  hygienic  point  of  view  that  the 
outer  clothes  of  people  who  work  for  their  living  should  be  made  of  washable 
materials  with  a  smootli  surface.  Domestic  servants  very  generally  follow 
this  rule,  but  among  the  working  classes  at  large  the  painters  are  almost  the 
only  section  who  habitually  wear  washable  overalls. 

The  dressing  of  the  hair  should  be  of  a  fashion  to  suggest  cleanUuess. 
Tumbled  hair  may  be  '  artistic,'  but  it  suggests  dust  and  a  .difficulty  of 
combing  which  is  not  quite  comfortable  for  the  thoughtful  onlooker.  Truly 
artistic  clothing  must  suggest  health  and  comfort.  It  must  not  be  tight,  nor 
must  the  folds  be  so  cumbersome  as  to  hamper  free  movement.  It  must  be 
suitable  for  the  chmate  and  season.  All  attempts  to  adopt  '  classic  styles,' 
i,e,  the  costume  once  worn  in  Athens,  which  is  fifteen  degrees  south  of  London,. 
must  end  in  failure. 

On  the  question  of  colours  we  have  little  to  say  except  that  the  dowdy 
half-tints  which  were  in  vogue  a  few  years  since,  in  so  much  as  they 
suggested  fading  and  shabbiness,  seemed  to  fail  in  the  first  law  of  sestheticism. 
The  colour  should  certainly  vary  with  the  season — cool  light  colours  for 
the  summer  and  '  warm  '  tints  for  the  winter. 

It  will  probably  be  useful  to  give  as  an  appendix  to  this  article  a 
few  receipts  which  will  be  found  serviceable  in  comiection  with  clothing. 
These  have  been  taken  from  the  sixth  edition  of  Cooley's  '  Cyclopa?dia  of 
Practical  Eeceipts,'  edited  by  E.  V.  Tuson  (London  :  J,  and  A,  Churchill;. 

Waterproofing. — 1,  Moisten  the  cloth  on  the  wrong  side  first  with  a  weak  solution  of 
isinglass,  and,  when  dry,  with  an  infusion  of  nut-galls. 

2.  Moisten  the  cloth  on  the  wrong  side  first  with  a  solution  of  soap,  and,  when  dry, 
with  a  solution  of  alum. 

3.  Eub  the  wrong  side  of  the  cloth  with  a  lump  of  beeswax  (perfectly  pure  and  free 
from  grease)  until  it  presents  a  light  but  even  white  or  greyish  appearance  ;  a  hot  iron  is 
then  to  be  passed  over  it,  and,  the  cloth  being  brushed  whilst  warm,  the  process  is  com- 
plete. AVhen  the  operation  has  been  skilfully  performed  a  candle  may  be  blown  out 
through  the  cloth  if  coarse,  and  yet  a  piece  of  the  same,  placed  across  an  inverted  hat, 
may  have  several  glassfuls  of  water  poured  into  the  hollow  formed  by  it  without  any  of 
the  liquid  passing  through. 

Waterproof  liquids,  for  boots,  shoes,  and  leather  articles. 

1.  India-rubber  in  fragments,  1  oz. ;  boiled  oil,  1  pint ;  dissolve  by  heat,  carefully 
applied,  then  stir  in  of  hot  boiled  oil  1  pint,  and  remove  the  vessel  from  the  fire. 

2.  Boiled  oil,  1  pint ;  beeswax  and  yellow  resin,  of  each  2  oz. ;  melt  them  together. 
Dubbing. — Black  resin,  2  lb. ;  tallow,  1  lb. ;  crude  cod  oil  or  train  oil,  1  gallon  ;  boil 

to  a  proper  consistence. 

Stains  and  spots  on  clothes  may  be  removed  with  a  little  clean  oil  of  turpentine  or 
benzol,  or  with  a  little  fuller's  earth  or  scraped  French  chalk  made  into  a  paste  with 
water  and  allowed  to  dry  on  them,  or  by  a  hot  tlat-iron  and  a  piece  of  blotting-paper. 

Fruit  and  ivine  stains  on  linen  commonly  yield  easily  to  hot  soap-and-water. 

I7ik  spots  and  recent  iron  mould  on  washable  fabrics  may  be  removed  by  dropping 
on  the  part  a  little  melted  tallow  from  a  common  candle  before  washing  the  articles,  or 
by  the  application  of  a  little  lemon  juice  or  powdered  cream  of  tartar  made  into  a  paste 
with  hot  water. 

Old  ink  spots  and  iron  mould  will  be  found  to  yield  almost  immediately  to  a  very 
little  powdered  oxalic  acid,  which  must  be  well  rubbed  upon  the  spot  previously  moistened 
with  boiling  water  and  kept  hot  over  a  basin  filled  with  the  same. 


CLOTHING  5Br^ 

Fireproofing. — It  is  vei-y  advisable  to  treat  light,  gauzy  articles  (such  as  muslin)  in 
some  way  to  prevent  them  from  tlaring  up  if  they  come  accidentally  in  contact  with  a 
light.  This  may  be  attained  by  steeping  the  fabric  in  almost  any  saline  solution.  Thus, 
cotton  or  linen  stuffs,  prepared  with  a  solution  of  borax,  phosphate  of  soda,  phosphate  of 
ammonia,  alum,  or  sal-ammoniac,  may  be  placed  in  contact  with  ignited  bodies  without 
their  suffering  active  combustion  or  bursting  into  flame.  The  salts  act  by  forming  a  crust 
of  incombustible  matter  on  the  surface  of  the  fibres. 

The  addition  of  about  1  oz.  of  alum  or  sal-ammoniac  to  the  last  water  used  to  rinse 
a  lady's  dress,  or  a  set  of  bed  furniture,  or  a  less  quantity  added  to  the  starch  used  to 
stiffen,  renders  them  uninflammable,  or  at  least  so  little  combustible  that  they  will  not 
blaze. 

For  fine  muslin,  tungstatc  of  soda  is  found  to  answer  better  than  any  of  the  above- 
named  salts.  '  Muslin  steeped  in  a  solution  containing  20  per  cent,  of  this  salt  is  perfectly 
non-inflammable  when  dry,  and  the  saline  film  left  on  the  surface  is  smooth  and  of  a  fatty 
appearance  like  talc,  and  therefore  does  not  interfere  with  the  process  of  ironing,  but 
allows  the  hot  iron  to  pass  smoothly  over  the  surface.  The  non-fulfilment  of  this  latter 
condition  completely  prevents  the  use  of  many  other  salts,  such  as  sulphate  or  phosphate 
of  ammonia,  which  are  otherwise  efficacious  in  destroying  inflammability — for  all  fabrics 
which  have  to  be  washed  and  ironed  '  (Watts). 


Eefeeence  to  Plate  of  Fibkes 


A.  Linen  (Linen  handkerchief).  B.  Cotton  (Sewing  cotton).  C.  Silk  (Silkworm 
cocoon).  D.  Wool  (Woollen  shawl).  E.  Hemp  (Eope).  F.  Coir  (Cocoa-nut  matting). 
G.  Jute  (The  raw  material).     H.  Fii,r  (Eabbit). 

(a)  Low  poiuer  (about  100  diameters),  (b)  (c)  High  power  (about  500  diameters).  la 
G,  (b)  represents  a  small  bundle,  (c)  a  single  fibre. 


PHYSICAL    EDUCATION 

BY 

FEEDEEICK  TEEVES,  F.E.C.S. 

SLTIGEON  TO  AXD  UECTnBEE  ON  ANATOMY  AT  THE  LONDON  HOSPITAL;  JIEMBER  OF  TIIE 
BOARD  OP  EXAMINERS  OP  THE  KOTAL  COLLEGE  OF  SUUGEOXS 


INTEODUCTOEY 

Writees  are  not  yet  weary  of  enlarging  upon  the  marvels  of  civilisation, 
upon  the  intellectual  development  of  the  human  race,  upon  the  triumphs  of 
human  ingenuity,  and  the  might  and  magnificence  of  human  culture.  He 
has,  indeed,  much  to  marvel  at  who  measures  the  gulf  which  separates  the 
polished  citizen  of  the  world  from  the  half-naked  and  quite  savage  barbarian. 
The  inventive  genius  of  the  modern,  the  high  development  of  each  craft  and 
industry  which  he  has  cultivated,  the  skill  of  the  nineteenth-century  artisan, 
the  general  intellectual  condition  of  the  masses  in  the  great  centres  of 
civihsation,  are  all  features  of  attraction  for  those  who  are  unceasing  in  the 
glorification  of  the  race.  The  great  elements  in  human  progress  afford, 
indeed,  proper  material  for  admiration.  There  is  no  one  but  would  admit 
that  the  advantages  of  the  civilised  man  over  the  savage  are  such  as  to  make 
reasonable  comparisons  scarcely  possible  ;  but  there  follows  upon  this  the 
question  as  to  whether  the  so-called  blessings  of  civilisation  represent  an 
unmixed  good.  The  intellectual  victory  has  been  great,  but  it  has  not  been 
effected  without  cost.  We  have  in  our  midst  the  inventor,  the  man  of 
genius,  the  handicraftsman,  but  we  have  also  the  weakling,  the  delicate,  the 
misshapen,  and  that  most  modern  product  of  all,  the  mannikin  of  the  city. 
This  pale,  wizened,  undersized  creature  represents  no  little  sacrifice  ;  he  is  a 
product  of  civilisation,  an  unintentional  manifestation,  but  a  characteristic  one. 

If  one  watches  the  stream  of  men,  boys,  and  girls  which  pours  out  at 
the  close  of  day  from  a  great  city  factory,  the  question  may  well  be  asked, 
Are  these  superior  to  the  savage  in  all  things,  and  are  there  no  points 
in  which  the  barbarian  could  claim  some  advantage  over  his  modern 
descendant  ? 

The  savage  Norseman  who  first  sailed  the  northern  seas  knew  Httle  of 
art  and  less  of  science,  but  he  had  great  lungs  and  a  stout  heart  and  mighty 
muscles  and  exhaustless  strength,  and  was  a  stranger — it  might  be  assumed 
— to  many  of  the  aches  and  pains  and  petty  illnesses  which  the  modern 
town  dweller  regards  as  a  natural  heritage. 

In  the  face  of  a  marvellous  social,  moral,  and  intellectual  development 
we  are  apt  to  lose  sight  of  the  fact  that  man  is  an  animal,  that  he  cannot  yet 
do  without  a  body,  and  that  a  strong  receptacle  for  the  mind  is  better  than 
a  frail  one. 

The  higher  type  of  savage  was  perfect  in  form,  lithe  in  movement,  keen  of 
vision,  and  strong  of  arm.  He  felt  in  his  veins  the  glow  of  life,  the  joy  of 
mere  vigour  thrilled  his  muscles,  the  instincts  of  mere  health  dignified  his 
movements.  If  he  pursued  physical  culture  to  an  exclusive  degree,  it  is 
possible  that  his  civilised  brother  may  carry  intellectual  finish  to  an  equal 
extreme. 

There  is  evidence  to  show  that  an  exclusive  development  of  what  are 
quite  properly  termed  the  higher  faculties  of  man  is  not  of  unmixed  advan- 
tage. Progress  is  so  rapid,  and  the  movements  of  daily  life  are  so  exacting, 
that  there  is  a  tendency  to  overlook  the  fact  that  man  cannot  live  by 
intellectual  bread  alone.  The  young  lad  is  taught  to  read  as  soon  as  he 
can  lisp,  and  to  write  as  soon  as  he  can  grasp  a  pen.  At  school  he  is 
forced  and  fostered  like  a  hot-house  plant,  and  when  he  is  old  enough  to- 


5-10  HYGIENE 

take  his  place  in  the  race  in  life  he  at  once  feels  the  fever  of  competition  and 
the  strain  of  incessant  endeavour. 

It  is,  however,  hecomiug  obvious  that  one  great  element  of  success 
in  hfe  is  bodily  strength  ;  and  that  he  who  has  every  mental  requirement 
and  the  finest  intellectual  finish  may  find  that  he  still  lacks  the  one  thing 
needed.  Sound  physical  health  enables  a  man  to  work  with  vigour  and 
freshness,  to  pass  unharmed  through  periods  of  unusual  pressure,  to  with- 
stand the  evils  of  wori-y,  to  preserve  a  clearness  and  acuteuess  of  mind  when 
others  are  worn  and  fretful  and  uncertain,  and  to  still  press  forward  when 
others  have  fallen  in  the  race. 

He  will  do  well  who  still  retains  in  the  midst  of  his  city  hfe  some  of  the 
quahties  of  the  men  of  the  plain.  He  will  find  that  muscular  strength  and 
good  lungs  are  not  without  value,  even  though  he  be  no  longer  dependent 
upon  the  hunter's  skill  for  his  daily  meal.  The  attributes  of  the  trapper 
and  the  seaman  are  attributes  which  cannot  be  without  service,  even  in 
the  murkiest  life  in  the  wilderness  of  a  great  city. 

It  is  noAV  more  or  less  clearly  recognised  that  no  skill,  no  learning,  no 
intellectual  greatness,  can  carry  with  it  its  fullest  influence  without  a  certain 
element  of  physical  capacity  in  the  individual. 

The  unduly  diligent  student  who  burns  the  midnight  oil,  who  cannot 
tear  himself  away  from  his  books,  who  moves  in  a  world  in  which  the  only 
sunshine  is  that  of  learning,  and  the  only  breeze  is  that  which  blows  from 
the  erudition  of  the  past,  is  often  a  miserable  object  enough  as  a  human 
being.  His  face  is  wan,  his  arms  are  feeble,  his  eyes  are  dim,  he  hves  in 
an  atmosphere  of  little  ailments,  and  he  has  few  pleasures  other  than  the 
joys  of  the  bookworm.  Such  a  man  would  make  no  less  progress  in  the 
present,  and  would  effect  no  less  influence  in  the  future,  if  he  would  devote 
some  leisure  to  the  cultivation  of  his  body.  A  clear  eye,  a  wiry  limb,  and  a 
ruddy  cheek  are  not  inconsistent  with  the  greatest  intellectual  development ; 
while  on  the  other  hand  there  are  many  poor  lads  who  have  been  crammed 
and  cultivated  until  they  are  mere  learned  invalids.  It  may  well  be  asked  of 
their  learning,  '  What  will  they  do  with  it  ?  '  Many  a  '  city  man  '  can  have 
but  little  knowledge  of  living,  however  much  he  may  know  of  '  life.'  His 
hurried  hours  of  work  are  followed  by  a  period  of  dulled  rest.  He  lives  in  the 
maze  caused  by  the  rush  of  passing  events,  he  knows  Httle  of  the  joys  of 
the  world  as  the  barbarian  knows  them,  and  his  journey  through  life  is  but 
at  a  halting  and  creaking  pace.  He  remains  a  partly  developed  creature 
who  has  never  attained  to  the  full  stature  of  a  man. 

Montaigne  well  says,  in  speaking  of  a  man  as  he  should  be,  '  I  would 
have  the  disposition  of  his  limbs  formed  at  the  same  time  with  his  mind. 
'Tis  not  a  soul,  'tis  not  a  body  we  are  training,  but  a  man,  and  we  must  not 
divide  him.' 

In  certain  directions  the  importance  of  simple  physical  health  and  strength 
cannot  well  be  exaggerated.  The  part  these  have  played  in  the  history  of  the 
British  race  has  been  magnificent  enough.  The  glories  of  Enghsh  enterprise, 
the  daring  and  hardihood  of  the  British  seaman,  the  unconquerable  pluck  of 
the  English  soldier,  have  taken  no  httle  share  in  forming  the  greatness  of  the 
British  nation.  The  love  of  sport  among  the  Enghsh,  the  delight  in  manly 
games  and  outdoor  exercises,  the  contempt  for  what  is  efi'eminate  and  feeble, 
are  outcomes  of  a  vigorous  health  and  a  sturdy  growth. 

There  is  no  need  to  modify  the  fact  that  the  position  of  Great  Britain 
among  European  nations  is  due  in  no  small  extent  to  quahfications  which 
have  been  the  glory  of  savage  peoples.  The  explorer  may  have  profound 
knowledge  and  a  preternatural  judgment,  but  they  avail  but  httle  if  he  be 


PHYSICAL  EDUCATION  541 

not  possessed  of  mere  rude  health  and  strength.  The  main  pride  of  the 
early  navigator  was  his  reckless  courage  and  his  sturdy  endurance.  The 
greatest  commander  would  have  proved  a  man  of  straw  had  he  not  at  his 
call  men  who  shirked  no  hardship  and  who  felt  no  fear. 

It  may  not  be  a  graceful  acknowledgment,  but  it  is  none  the  less  true 
that  the  power  of  the  English  people  has  depended  in  no  little  degree  upon 
those  very  humble  qualities  which  make  '  a  good  animal.' 

There  is  an  instinct  which  impels  the  human  being  to  seek  health  in 
muscular  exercise  and  pleasure  in  physical  exertion.  The  very  restlessness 
of  the  child  is  an  expression  of  this.  It  is  often  said  of  a  child  that  he  or 
she  is  never  still.  It  is  an  excellent  feature.  It  is  as  unreasonable  to  expect 
a  young  lad  to  keep  quiet  as  to  expect  him  not  to  cough  when  he  has  a  cold. 
The  infant  jumps  and  kicks  and  crows ;  the  child  shows  its  natural 
promptings  by  incessant  restlessness.  The  schoolboy,  if  he  be  vigorous  and 
healthy,  appears  to  have  acquired  the  art  of  perpetual  movement.  The 
mad  rush  of  a  crowd  of  schoolboys  from  the  schoolroom  the  moment 
they  are  free  is  characteristic  enough  and  pleasant  to  witness.  The  limbs 
and  muscles  which  have  been  so  long  still  feel  the  need  of  movement  as  a 
half  suffocated  man  feels  the  need  of  air.  The  boy  who  is  the  first  to  reach 
the  open  air  beyond  the  schoolhouse  door  has  probably  not  an  evil  future 
before  him  ;  he  has  at  least  made  a  good  beginning.  He,  on  the  other  hand, 
who  crawls  out  last,  who  feels  no  irresistible  impulse  to  jump  and  shout,  is 
in  some  way  abnormal ;  he  is  ill  m  health  or  imperfect  in  construction. 
He  may  prove  an  excellent  scholar,  but  the  terrible  earnestness  of  the  race 
of  life  is  not  best  met  by  mere  scholarship. 

Throughout  life  there  exists  in  all  healthy  bodies  this  natural  craving  for 
exercise,  and  a  man  may  consider  that  he  has  reached  an  unfortunate  period 
in  his  career  when  he  has  ceased  to  feel  that  impulse. 

Muscles  can  grow  only  by  exercise  and  by  the  simple  expedient  of  using 
them.  The  disused  muscle  wastes,  and  becomes  fatty  and  anaemic.  Mus- 
cular tissue  occupies  nearly  every  part  of  the  body,  from  so  dehcate  a  piece 
of  mechanism  as  the  eye  to  so  simple  a  structure  as  the  biceps  humeri. 
Exercise  implies  not  merely  the  development  of  the  muscles  of  the  limbs, 
it  implies  also  the  healthy  use  of  the  muscle  of  the  heart,  of  the  muscles  of 
respiration,  of  the  muscular  tissue  of  the  arteries,  and  of  the  muscular  ele- 
ments of  all  parts  capable  of  movement.  Such  movement  carries  with  it  of 
necessity  an  activity  in  the  nervous  system,  an  activity  in  the  secreting 
organs  and  in  the  organs  of  excretion. 

Movement,  indeed,  within  proper  bounds  is  essential  to  the  full  develop- 
ment and  perfect  maintenance  of  the  health  of  the  body.  The  body  is  a 
machine  with  the  peculiar  attribute  that  the  more  it  is  used,  within  reason- 
able limits,  the  stronger  and  more  capable  it  becomes.  It  gathers  strength 
by  movement,  and  that  strength  is  to  be  gauged,  not  by  mere  muscular  force, 
but  by  the  perfect  functional  condition  of  every  part  and  of  every  organ. 

Physical  Education  involves  exercise  and  movement.  We  know  of  no  other 
means  of  developing  any  portion  of  the  organism,  provided  that  the  supply  of 
food  and  of  air  be  sufficient.  Exercise  means  growth,  functional  vigour,  and 
the  maintenance  of  a  high  standard  of  organic  life.  Undue  rest  imphes  decay, 
feebleness,  and  a  debased  standard  of  functional  value.  Absolute  rest  is 
found  only  in  death. 

Of  artificial  means  of  attaining  physical  perfection  there  are  none.  Every 
structure  and  tissue  must  be  duly  and  accurately  exercised  and  kept  in 
proper  movement ;  and  this  applies  as  well  to  the  ciliary  muscle  of  the  eye 
as  it  does  to  the  great  flexors  of  the  leg,  as  well  to  the  peptic  glands  of  the 


542  HYGIENE 

stouiaeli  as  to  the  cells  of  the  cortex  of  the  brain.  The  body  is  like  a  busy 
towii ;  so  long  as  there  is  activity  within  its  walls,  and  so  long  as  every  nook 
and  corner  is  alive  with  the  best  energies  of  those  who  dwell  therein,  things 
fare  well ;  but  when  one  section  Hags,  when  inactivity  falls  upon  this  quarter 
or  upon  that,  there  comes  some  retrogression,  some  halting  in  a  progress 
which  had  hitherto  been  even  and  energetic.  If  the  intellect  is  to  be  culti- 
vated, the  brain  must  be  exercised.  He  who  wishes  to  acquire  the  far  vision 
of  the  seaman  must  use  his  eyes  like  a  seaman,  and  he  who  would  develop 
the  hmiter's  keenness  of  hearing  and  powers  of  endurance  must  lead  the 
hunter's  life.    . 

To  learn  how  to  rightly  exercise  every  part  and  organ  of  the  body,  and 
how  to  effect  this  without  undue  effort  or  injurious  strain,  is  to  discover  the 
ehxir  of  life  and  such  a  philosopher's  stone  as  will  render  the  short  tenure 
of  human  life  as  free  from  bodily  troubles  as  the  art  of  man  can  make  it. 

It  is  no  longer  possible  to  say,  as  Herbert  Spencer  did  some  twenty  years 
ago,  that  the  inhabitants  of  this  country  take  an  interest  in  the  rearing  of  the 
offspring  of  all  creatures  except  themselves.  Civilisation  has  not  yet  greatly 
impaired  the  unconquerable  love  of  sport  and  the  passion  for  movement  and 
violent  exercise  which  appear  to  be  the  heritage  of  the  British  race.  There 
is  some  evidence  to  shoAV  that,  taking  averages,  we  have  not  diminished 
either  in  height  or  in  girth.  There  is  evidence  of  deterioration  among  the 
poorer  inhabitants  of  great  cities,  but  among  the  more  favoured  classes  it 
would  appear  that  no  change  has  taken  place  which  indicates  a  distinct 
downward  tendency.  Within  recent  years  there  has  been  a  remarkable 
revival  of  interest  in  sports,  games,  and  athletic  exercises  of  all  kinds.  It 
was  not  until  1875  that  the  English  Channel  was  crossed  by  a  swimmer.  So 
far  as  it  is  known,  it  was  not  until  the  year  1877  that  a  human  being  had 
ever  leapt  from  the  ground,  mthout  artificial  aid,  to  the  height  of  6  feet 
2  inches.  A  man  can  now  jump  across  a  gap  23  feet  in  width,  a  mile  has 
been  run  in  less  than  4^  minutes,  and  600  miles  have  been  walked  in  one 
week. 

It  is  quite  obvious  that  the  term  Physical  Education  must  include  the 
regulation  of  the  functions  and  movements  of  the  entire  body.  With  such 
as  concern  the  supply  of  suitable  food  and  wholesome  air,  and  the  observa- 
tion of  what  are  known  as  simple  hygienic  conditions,  the  present  paper  has 
no  concern. 

It  is  necessary  here  to  deal  only  with  that  most  conspicuous  factor  in 
physical  culture  which  concerns  the  due  and  proportionate  exercise  of  the 
muscles  of  the  body. 

In  the  following  article  we  shall  first  consider  the  general  effects  of 
exercise,  including  the  subjects  of  fatigue,  overwork,  and  want  of  exercise, 
and  secondly  the  effects  of  specific  exercises. 


THE    GENERAL   EFFECTS   OF   EXEECISE 

1.  The  Effect  of  Exeecise  upon  the  Development  axd 
PropoPvTions  of  the  Body 

Exercise,  as  here  understood,  may  be  represented  by  such  natural,  sys- 
tematic, and  well-regulated  exercises  as  enter  into  the  life  of  every  healthy 
public  schoolboy,  together  with  such  special  gymnastics  which  may  be  con- 
sidered to  be  necessary  in  particular  cases.  It  must  be  understood  that  the 
object  of  exercise— as  here  intended — is  not  to  develop  athletes,  acrobats,  and 


PHYSICAL  EDUCATION  543 

phenomenally  strong  men,  but  to  encourage  and  maintain  the  highest  and 
most  equable  development  of  the  body. 

The  secret  of  the  size  and  proportions  of  the  future  man  lies  buried  in 
the  ovum  from  which  the  individual  is  developed.  It  may  be  said,  indeed, 
that  there  are  two  proportions  possible  in  every  human  body — first,  that 
which  is  congenital,  inherited,  and  predetermined  ;  and,  secondly,  such  an 
increase  or  modification  of  these  proportions  as  may  be  effected  by  proper 
exercise. 

The  child  of  short  and  stunted  parents  will  probably  also  be  short  and 
stunted,  and  may  remain  so  in  spite  of  an  elaborate  physical  training.  An 
infant  Bushman  transformed  suddenly  to  a  cotter's  home  in  Scotland  could 
never  be  expected  to  attain  the  proportions  of  the  young  Highlanders  with 
whom  his  lot  had  been  cast.  In  estimating  the  effect  of  exercise  and  in 
speculating  upon  its  possible  powers  in  this  direction  a  constant  reference 
must  be  made  to  those  inherited  factors  which  are  quite  beyond  control. 
Exercise  cannot  make  a  man  a  giant,  nor  can  it  with  any  certainty  develop 
a  modern  Hercules.  It  can,  however,  influence  the  growth  and  structural 
perfection  of  the  body  in  a  manner  which  is  definite  and  to  some  extent 
remarkable. 

Exercise  increases  the  size  of  a  muscle,  the  proportions  of  its  tendon  and 
the  power  it  can  command.  After  undue  rest  a  muscle  becomes  thin,  soft, 
wasted,  and  feeble.  The  stronger  the  muscles,  the  finer  and  denser  are  the 
aponeuroses  with  which  they  are  connected  and  the  stouter  are  the  fascite 
which  hold  them  in  position.  Muscles  act  upon  articulations.  The  duly 
exercised  joint  has  a  good  covering  of  cartilage,  powerful  ligaments,  and 
well- developed  bony  parts.  The  joint  which  has  been  long  kept  at  rest  has 
wasted  ligaments,  a  thinned  cartilage,  and  bones  of  smaller  proportions. 
It  becomes,  moreover,  hypersesthetic  from  disuse,  and  the  tissues  around  are 
found  to  be  flabby  and  anemic.  Within  certain  somewhat  narrow  limits 
the  mechanical  possibilities  of  a  joint  can  be  much  extended  by  exercise. 

Muscular  strength,  moreover,  influences  the  size  of  the  bones  upon  which 
the  muscles  act.  The  skeleton  of  a  feeble  individual  compares  in  a  very 
marked  manner  with  the  skeleton  of  a  muscular  person  of  the  same  height 
and  the  same  age.  The  bone  of  the  muscular  individual  is  stronger,  firmer, 
and  denser ;  it  is  actually  larger,  and  the  so-called  muscular  surfaces  and 
ridges  are  more  conspicuously  marked. 

Exercise  induces  a  more  vigorous  respiration,  and  u.nder  increased 
breathing  efforts  the  lung  capacity  is  increased  and  the  size  of  the  thorax  is 
augmented.  Exercise,  moreover,  accelerates  the  blood  circulation,  and  it  is 
needless  to  point  out  the  effect  an  increased  blood  supply  has  upon  the  size 
and  development  of  the  tissues  concerned. 

1.  The  Development  of  the  Body. — Before  considering  the  special  effects 
of  exercise  upon  the  growth  of  the  body  it  is  necessary  to  take  note  of  what 
may  be  termed  the  average  measurements  of  the  human  organism. 

The  principal  facts  with  regard  to  the  growth  of  the  body,  its  weight 
and  height  at  various  periods  of  life,  its  comparative  proportions  in  males 
and  females,  and  other  features  concerned  in  Anthropometry,  are  briefly  set 
forth  in  the  following  tables. 

The  principal  tables  are  derived  from  Mr.  Charles  Eoberts's  '  Manual  of 
Anthropometry,'  and  to  this  admirable  and  classical  work  the  reader  is  referred 
for  more  extensive  details.  Much  use  has  been  made  also  of  the  Eeport  of 
the  Anthropometric  Committee  of  the  British  Association,  1882-3.  This 
report  was  drawn  up  by  Mr.  Eoberts  and  Sir  E.  W.  Eawson,  nnd  has  been 
published  as  an  appendix  to  Mr. Eoberts's  '  Manual.'   These  two  works  provide 


544 


HYGIENE 


tlie  most  precise  data  upon  Anthropometry,  so  far  as  the  Enghsh  race  is 
concerned,  which  we  possess. 

It  may  in  the  first  place  be  well  to  tabulate  the  periods  at  which  the 
various  parts  of  the  skeleton  are  completed,  so  far  as  the  facts  of  osteology 
guide  us. 

The  Spine ) 

The  Pehas -     The  25th  year 

The  Shoulder  Girdle   ....  J 

The  Upper  Limb 


The  Lower  Limb 


The  20th  year 
The  Femur  the  20th  year 
The  Tibia  the  22nd  year 
The  Fibula  the  24th  year 


Table  I. — SJioiuing  the  average  stature  {without  shoes)  and  tJw  average  weight  [incUuling 
clothes)  at  all  ages  of  the  general  population  of  Great  Britain.  {All  classes.  Town 
and  country.)  Number  of  observations  on  which  the  averages  are  founded.  Stature  : 
Males,  37,574.  Females,  4,616.  Weight :  Males,  33,043.  Females,  4,685.  (From  th& 
Eeport  of  the  Anthropometric  Committee,  1883.) 


Males 

Peniales 

Age  last 

Average 

In- 

Average 

In- 

Age last 
birthday 

Average 

In- 

Average 

In- 

height, 

crease  in 

weight, 

crease  in 

height. 

crease  in 

weight, 

crease  in 

birthday 

inches 

inches 

pounds 

pounds 

inches 

inches 

pounds 

pounds 

Birth 

19-52 

7-1 

Birth 

19-31 

6-9 

_ 

0-1 

27-00 

— 

— . 

— 

0-1 

24-83 

5-52 

— 

— 

1 

33-50 

— 

— 

— 

1 

27-50 

2-67 

20-1 

— 

2 

33-70 

32-5 

— 

2 

32-33 

4-83 

25-3 

5-2 

3 

36-82 

34-0 

1^5 

3 

36-23 

3-90 

31-6 

6-3 

4 

38-46 

1-64 

37-3 

3-3 

4 

38-26 

2-03 

36-1 

4^5 

5 

41-03 

2-57 

39-9 

2-6 

5 

40-55 

2-29 

39-2 

3^1 

6 

44-00 

2-97 

44-4 

4-5 

6 

42-88 

2-33 

41-7 

2^5 

7 

45-97 

1-97 

49-7 

5-3 

7 

44-45 

1-57 

47-5 

6^8 

8 

47-05 

1-08 

54-9 

5^2 

8 

46-60 

2-15 

52-1 

4-6 

9 

49-70 

2-65 

60-4 

5^5 

9 

48-73 

2-13 

55-5 

3^4 

10 

51-84 

2-14 

67-5 

7-1 

10 

51-05 

2-32 

62-0 

6^5 

11 

53-50 

1-66 

72-0 

4-5 

11 

53-10 

2-05 

68-1 

6-1 

12 

54-99 

1-49 

76-7 

4^7 

12 

55-66 

2-56 

76-4 

8-3 

13 

56-91 

1-92 

82-6 

5-9 

13 

57-77 

2-11 

87-2 

10-8 

14 

59-33 

2-42 

92-0 

9-4 

14 

59-80 

2-03 

96-7 

9-5 

15 

62-24 

2  91 

102-7 

10-7 

15 

60-93 

1-13 

106-3 

9-6 

16 

64-31 

2-07 

119-0 

16^3 

16 

61-75 

•82 

113-1 

6-8 

17 

66-24 

1-93 

130-9 

11-9 

17 

62^52 

•77 

115-5 

2-4 

18 

66-96 

■72 

137-4 

6-5 

18 

62-44 

— 

12M 

5-6 

19 

67-29 

-33 

139-6 

2-2 

19 

62-75 

•23 

123^8 

2-7 

20 

67-52 

•23 

143-3 

3-7 

20 

62-98 

•23 

123-4 

•6 

21 

67-63 

•11 

145-2 

1-9 

21 

63-03 

•05 

121-8 

— 

22 

67-68 

•05 

146-9 

1-7 

22 

62-87 

— . 

123-4 

— 

23 

67-48 

— 

147-8 

•9 

23 

63-01 

— 

124-1 

•7 

24 

67-73 

-05 

148-0 

•2 

24 

62-70 

— 

120-8 

— 

25-30 

67-80 

•07 

152-3 

4^3 

25-30 

62-02 

— 

120-0 

— 

30-35 

68-00 

•20 

159-8 

7^5 

30-35 

\ 

— 

120-8 

— 

35-40 

68-00 



164-3 

4-5 

35-40 

— 

120-8 

— 

40-50 
50-60 

67-96 
67-92 

— 

163-3 
166-1 

1-8 

40-50 
50-60 

-  61-15 

— 

118-0 
1040 

— 

60-70 

67-41 

— 

158-1 

2-0 

60-70 

— 

— 

— 

70 

69-22 

1^22 

182^1 

— 

70 

1 

106-0 

i 

The  following  comments  upon  the  series  of  tables  of  which  the  above  is 
an  abstract  are  furnished  by  the  Anthropometric  Committee  : — 

1.  Growth  is  most  rapid  during  the  first  five  years  of  life. 

2.  From  birth  to  the  age  of  five  years  the  rate  of  growth  is  the  same  in 
both  sexes,  girls  being  a  little  shorter  in  stature  and  lighter  in  weight  than  boys. 


PHYSICAL  EDUCATION 


045 


8.  From  five  to  ten  years  boys  grow  a  little  more  rapidly  than  girls,  the 
difference  being  apparently  due  to  a  check  in  the  growth  of  girls  at  these  ages. 

4.  From  ten  to  fifteen  years  girls  grow  more  rapidly  than  boys,  and  at  the 
ages  of  eleven  and  a  half  to  fourteen  and  a  half  are  actually  taller,  and  from 
twelve  and  a  half  to  fifteen  and  a  half  years  actually  heavier  than  boys. 
This  difference  appears  to  be  due  to  a  check  in  the  growth  of  boys  as  well  as 
an  acceleration  in  the  growth  of  girls  incident  on  the  accession  of  puberty. 

5.  From  fifteen  to  twenty  years  boys  again  take  the  lead,  and  grow  at 
first  rapidly,  then  gradually  slower,  and  complete  their  growth  at  about 
twenty-three  years.  After  fifteen,  girls  grow  very  slowly,  and  attain  their 
full  stature  about  the  twentieth  year. 

6.  The  tables  show  a  slow  but  steady  increase  in  stature  up  to  the  fiftieth 
year,  and  a  more  rapid  increase  in  weight  up  to  the  sixtieth  year  in  males, 
but  the  statistics  of  females  are  too  few  after  the  age  of  twenty-three  to  deter- 
mine the  stature  and  weight  of  that  sex  at  the  more  advanced  periods  of  life. 

'  It  is  probably  due  to  the  greater  or  less  development  of  the  body  at  the 
time  of  the  accession  of  puberty,'  writes  Mr.  Eoberts, '  that  the  final  difference 
in  the  height  of  individuals  is  chiefly  to  be  attributed  ;  hence  the  influences 
which  promote  or  retard  growth  at  this  period  are  most  deserving  of  study. 
In  boys  puberty  occurs  later,  and  is  less  regular  and  decided,  than  in  girls. 
The  transition  from  boyhood  to  manhood  extends  over  a  period  of  three  to 
four  years,  and  is  accompanied  by  increased  physical  development  of  the 
body ;  but  girls  develop  into  women  in  a  few  months,  and  with  the  complete 
establishment  of  puberty,  growth  in  height  is  much  diminished,  and  often 
ceases  altogether.' 

As  a  further  contribution  to  the  subject  of  the  growth  of  boys  the  follow- 
ing tables  compiled  by  Maclaren  may  be  added  : — 


Table  II. — Showing  the  State  of  Growth  and  Development  between  the  ages  of  10  and  18 
years,  being  the  averages  of  the  actual  measurements  of  100  boys  at  each  age.  (Maclan^en} 


Age 

Height 

Weight 

G-irth  of  chest 

Forearm 

Upper  arm 

Tears 

Pt.     in. 

St.    lb. 

Inches 

Inches 

Inches 

10 

4     5i 

4     9 

251 

7i 

7| 

11 

4     7 

5     0 

26i 

7i 

8 

12 

4     8f 

5     8i 

27i 

8 

8i 

13 

4  10| 

6    Oi 

28| 

®t 

l^ 

14 

5    Of 

6    9 

29  i 

8| 

9 

15 

5     3 

7     5i 

30| 

9 

9* 

16 

5     5 

8  4 

32i 

9* 

m 

17 

5     7 

9     2i 

34i 

10 

11 

18 

5     8 

9  11 

35i 

lOJ 

Hi 

Table  III.— Abstract  of  preceding  Table  showing  average  Annual  Bate  of  Growth  and 
Development  from  year  to  year.     {Maclaren) 


- 

Height 

Weight 

Girth  of 
chest 

Forearm 

Upper  arm 

Inches 

Lb. 

Inches 

Inches 

Inches 

From  10  years 

to  11  years    . 

^ 

5 

i 

i 

4 

„     11 

12      „       . 

2 

8i 

■^4 

i 

4 

„     12 

13      „ 

If 

6 

i 

J 

„     13 

14      „ 

n 

8| 

i 

4 

h 

„     14 

15      „       . 

H 

lOi 

-■■l 

* 

■^ 

„     15 

16      „        . 

2 

13 

1| 

1 

* 

„     16 

17      „ 

2 

12 

1  3 
■"■4 

4; 

„     17 

18      „ 

1 

8i 

4 

4 

VOL.    I. 


N  N 


546 


HYGIENE 


Some  children  appear  to  grow  by  fits  and  starts.  Children  who  have  re- 
mained for  many  successive  years  under  the  average  height  may  suddenly 
shoot  up  and  attain  more  than  the  normal  stature  when  they  reach  adult  age. 
(See  in  connection  with  this  matter  Case  4,  Table  VII.) 

The  extremes  in  development  are  well  illustrated  by  the  following  obser- 
vations made  by  ]\Iaclaren.  They  give  the  result  of  the  examination  of  100 
University  men  (fi-eshmen)  who  Avere  not  especially  selected. 


The  greatest 

The  smallest 

developmeuts 

(leveloiimeuts 

Height 

.     6  ft.  6  in. 

5  ft.  2  in. 

Weight 

.     12  St.  2  lb. 

7  St. 

Chest  girth 

.     39  in. 

27i  in. 

Forearm     . 

.     113  in. 

8^  in. 

Upper  arm 

.     12-|  in. 

8|  in. 

The  effect  of  occupation  and  social  and  physical  condition  upon  develop- 
ment is  well  demonstrated  by  the  statistics  prepared  by  Mr.  Roberts  and  the 
Anthropometric  Committee. 

The  following  tables  are  derived  (in  abstract)  from  the  Report  of  the 
Committee  : — 

Table  IV. — Relative  Height  of  Boys  at  the  age  of  11  to  12  ijears  under  different 
social  and  physical  conditions  of  life. 

Average  height 
Public  schools  (country) .......     54"98  inches 

Middle-class  schools  ; 

Upper  (towns)  .......     53'85       „ 

Lower  (towns)  .......     .53-70       ,, 

Elementary  schools : 

Agricultural  labourers      ......     53-01       ,, 

Artisans  (town)         .......     52-()0       ,, 

Factory  hands  (country) 52-17       ,, 

Factory  hands  (towns)     ......     51-56       „ 

Military  asylums      .......     51-20       ,, 

Industrial  schools 50-02      „ 

T.U3LE  V. — Relative  Height  of  Adults  of  the  ages  from  25  to  30  years  under  different 
social  and  i>hysical  conditions  of  life. 


Upper  classes,  professional  classes 

Commercial  classes,  clerks,  shopkeepers,  &c.  . 
Agricultural  labourers,  miners,  sailors,  Ac.     . 
Artisan  classes  (towns)  ...... 

Factory  hands,  workers  at  sedentary  trades  — e.g.  tailors 


Average  heifrht 
()y-14  inches 
07-95      „ 
07-51      „ 
00-61      „ 
65-92      „ 


The  question  of  the  relation  of  weight  to  height  will  be  found  considered 
in  Table  I. 

Table  VI.  gives  the  average  chest-girth  in  males  at  different  periods  of 
life  (see  also  Tables  II.  and  III.).  The  chest-girth  in  males  shows  an  increase 
at  a  rate  similar  to  that  of  the  weight  up  to  the  age  of  fifty  years,  but  it 
appears  to  have  no  definite  relation  to  stature. 


Table  VI.- 

Age  next 
birthday 

10  . 

11  . 

12  . 

13  . 

14  . 

15  . 


-Average  Chest-girtli  {empty)  in  inclies  in  Males  of  all  classes  at  different  ages 
[licport  of  Anthropometric  Committee). 


Chest  girth 
in  inches 

Age  next 
birtliday 

.     2610 

16     .        .        . 

.    26-58 

17     .         .         . 

.     27-20 

18     .        .        . 

.     28-03 

19     .        .        . 

.     28-46 

20     .         .         . 

.     29-74 

21     .         .         . 

Chest  girth 

Age  next 

Chest  girth 

in  inches 

birthday 

in  inches 

31-53 

22     . 

.     35-33 

33-64 

23     . 

.     35-62 

34-19 

24     . 

.     35-82 

34-49 

25-29   . 

.     .36-18 

34-98 

30-35   . 

.     37-08 

35-25 

36-50  . 

.     37-58 

PHYSICAL  EDUCATION 


547 


The  effect  of  systematised  exercise  upon  the  growth  and  development  of 
hoys  and  men  may  now  be  considered.  In  the  Keport  of  the  Anthropometric 
Committee  the  measurements  of  eighty-nine  professional  and  amateur  athletes 
are  given  with  the  following  results,  '  Their  average  stature  exceeds  that  of 
the  general  population  from  which  they  are  drawn  by  O'GB  inch,  while 
their  average  weight  falls  short  of  that  standard  by  14'5  lb.  The  ratio  of 
weight  to  stature  is  in  the  athletes  2-100  lb.  and  in  the  general  population 
2*323  lb.  for  each  inch  of  stature.  Thus  a  trained  athlete;  whose  stature  is 
5  feet  7  inches  should  weigh  10  stone,  while  an  untrained  man  of  the  same 
height  should  weigh  11  stone.' 

Table  VII. — To  show  the  Effects  of  Systematised  Exercise  2ipo7i  growth  and  develo'imient 

(Maclarcn). 


- 

Measurements,  &c. 

Increase 

Reiuiarks 

Case          Date 

03 

Height 

Weight 

1 

iH 

a  a 

4^ 

+3 

bo 

1 

ts 

la 

pa 

h 

s 

In. 

— i 

In. 

a 

^ 

0 

S  s 

Ft.  in. 

St.  lb. 

In. 

In. 

Lb. 

In. 

In. 

In. 

1 

1861  June 

10 

4    6| 

4  10 

26 

n 

n 

1862  Sept. 

11 

4    9| 

5     5 

281 

H 

Si 

2| 

9 

21 

1^ 

1 

Height  above   average. 

1863  Sept. 

12 

4  lOa 

6     0 

301 

H 

8^ 

li 

9 

2 

1 

Other  measurements, 

1864  June 

13 

5     2i 

7    2 

321 

n 

9|- 

H 

16 

2 

1 

1 

average. 

1865  May 

14 

5     5i 

8     3 

351 

4 

101 

3f 

15 

3 

i 

Prom   commencement, 

1866  May 

15 

5     9 

10     2 

S7i 

11 

12 

H 

27 

2 

11 

It 

growth  rapid  and  siis- 

1867  Sep't. 

16 

5     9i 

10  13 

381 

11^ 

12 1 

1 

11 

1 

i 

f 

tained,  with  regular  | 

1868  Sept. 

17 

5  10| 

11    2 

391   llf 

13a 

11 

3 

1 

i 

1 

and  uniform  develop- 







ment. 

Total  increase    . 

16 

90    131 

H 

H 

2 

1860  Jan. 

12 

4    1| 

3  13     ;  23i 

6^ 

6 

Height  and    all   other 

1860  July 

12 

-4     3| 

4     0     1  24 

7 

6| 

H 

1 

i 

i 

t 

measurements  greatly 

1860  Dec. 

13 

4    4i 

4    1 

241 

7 

7 

1 

1 

2 

i 

fteZow  average.  Whole 

1861  Dec. 

14 

4    4i 

4     7 

25 

H 

7i 

6 

1 

4 

frame     stunted    and 

1862  July 

14 

4     5| 

4     8 

26 

n 

n 

2 

1 

i 

i 

i 

dwarfish.     Advance- 

1863 Mar. 

15 

4     7i 

4  12 

261 

H 

7f 

n 

4 

i 

8" 

g- 

ment  at   first  slight 

1864  July 

16 

4  llA 

6     6 

201 

4 

8i 

4 

22 

3 

1 

11 

and    very    in-egolar. 

afterwurils  rapid  and 

comparatively  regular. 

Total  increase    . 

9| 

35 

6 

21 

2| 

3 

1859  Dec. 

14 

4     5 

6    1     i  261 

8    1  7i 

Height  greatly    below 

1860  Sept. 

14 

5     2 

6    4 

29 

9 

9^ 

11 

3 

^ 

1 

15 

average ;  other  mea- 

1861 July 

15 

5     4i 

7    7 

30 

9 

H 

2| 

17 

1 





surements  also  consi- 

1862 Sept. 

15 

5     7| 

8  12 

341 

10 

IH 

19 

H 

1 

H 

derably    below   ave- 

rage.     Instant     and 



— 



— 

extreme  acceleration 

Total  increase    . 

161 

39 

8 

2 

31 

of  growth  with  mode- 
rate increase  in  deve- 

lopment. 

4 

1859  Oct. 

19 

5    2| 

8    0 

301 

9 

9i 

1859  Dec. 

— 

5     Si 
5     3f 

8    1 
8    1 

33 
33 

91 

101 
101 

t 

1 

21 

1 

1 

Well  proportioned.  A 
remai-kable     feature 

1860  Jan. 

20 

° 

lost 

is  the    renewal  and 

—        — 

— 

5    4i 

8    1 

331 

H 

101 

1 



1 



steady   continuation 

—      June 

— 

5    4| 

8    3 

34 

4 

101 

1 

2 

1 





of  the  upward  growth 

—        — 

— 

5    4f 

8    5 

341 

91 

10* 

2 

i 

1 

i 

which  had  been  pre- 

2_ 

maturely  arrested. 

Total  increase    . 

2 

5 

n 

1 

1 

5 

1859  Oct. 

17 

6     0 

9    4 

301     8| 

91 

Of     delicate      frame : 

1860  Jan. 

17 

6     0 

9     9 

321     91 

10 

5 

2 

1 

3 

chest  fiat  and  narrow, 

1860  June 

18 

6     01 

9  111 

34       9a 

101 

1 

21 

11 

£ 

1 

with  sternum  much 

1860  June 

18 

6     Oi 

9  13 

341     9| 

lOi 

a 

*^2 

■J 

— 

4 
4 

depressed. 

Total  increase    . 

i 

9 

4 

1 

11 

\ 

N  N  2 


648 


HYGIENE 


This  question  of  the  effect  of  systematic  exercise  upon  development  has 
been  fully  dealt  with  hy  Mv.  Maclaren. 

His  tables  dealing  with  the  subject  are  of  great  value,  and  should  be  con- 
sulted by  all  those  who  are  interested  in  the  matter.  In  the  appended  tables 
a  selection  from  these  statistics  is  given.  The  normal  increase  in  height 
and  weight,  as  given  in  Table  I.,  must  be  taken  into  consideration. 

Table  VIII. — Measurements  of  twelve  Non-commissioned  Officers  {selected  to  be  qualified 
as  Military  Gymnastic  Instructors  after  eight  months'  training.     (Maclareii.) 


Increase  noted  at  end  of  period 

Age 

Hei 

1 
jht         1         Weight 

G  irth  of  chest 

Forearm 

Upper  arm      | 

Tears 

lE 

Lb. 

In. 

In. 

In. 

19 

13 

4:V 

1 

^ 

21 

i 

10 

H 

1 

H 

23 

i 
1 

■ 

9 

3i 

1 

H 

23 

9 

u 

H 

1 

23 

10 

1 

1 

23 

J 

^                       9 

2 

s 

1 

23 

J 

5 

2i 

i 

1 

24 

i 

i                     12 

5 

1 

li 

26 

1                       6i 

3 

i 

4 

li 

26f 

\                       9 

1 



1 

28 

. 

^                      13 

3 

H 

1^ 

28 

i 

\                    16 

3 

1^ 

1 

In  an  examination  of  Tables  VII.  and  VIII.  the  increase  in  weight  under 
systematised  exercise,  after  allowing  for  normal  increase,  is  noteworthy. 

In  the  matter  of  increase  in  growth  Case  4,  Table  VII.,  is  interesting 
as  showing  the  renewal  of  growth  after  premature  arrest,  the  young  man 
growing  2  inches  after  nineteen.  Mr.  Maclaren  gives  several  other  instances 
of  this  sudden  growth  after  premature  arrest.  In  Table  VII.  the  increase 
in  height  of  the  older  men  in  the  list  is  of  interest.  In  the  majority  it  may 
be  due  to  a  greater  erectness  of  the  figure,  to  the  lessening,  therefore,  of  some 
of  the  curvature  of  the  spine,  and  perhaps  to  some  increase  in  the  interverte- 
bral substances. 

In  the  case  of  the  soldiers  in  Table  VIII.  the  question  of  the  improvement 
of  the  carriage  can  scarcely  come  into  consideration,  and  the  increase  in 
height  from  ^th  to  |ths  of  an  inch  in  the  last  four  men  must  be  ascribed  to 
changes  in  the  tissues.  In  Case  3,  Table  VII.,  the  immediate  effect  of  system- 
atised exercise  is  apparently  shown  by  a  remarkable  increase  in  height  of  no 
less  than  11  mches  in  a  period  of  nine  months. 

A  further  point  in  these  tables  must  be  noticed,  and  that  is  the  remark- 
able increase  in  the  circumference  of  the  chest,  which,  it  would  appear,  may 
be  obtained  by  systematic  exercise. 

An  increase  of  3  to  4  inches  in  the  girth  of  the  thorax  may  no  doubt 
be  in  great  part  ascribed  to  muscular  development  in  the  pectoral  and  sca- 
pular regions.  It  involves,  however,  an  increased  respiratory  power,  and  a 
greater  breathing  capacity. 

In  a  country  where  lung  diseases  are  so  common  as  they  are  in  England, 
it  is  difficult  to  speak  too  strongly  of  the  importance  of  obtaining  a  full 
development  of  the  chest. 

Physicians  recognise  the  part  played  by  a  narrow  thorax  and  a  feeble 
breathing  power  in  aiding  the  evolution  of  chronic  lung  disease  and  in  pro- 
moting the  progress  of  such  processes  as  are  acute. 


PHYSICAL  EDUCATION  549 

Considering  the  definite  and  apparently  assured  results  of  physical  training 
in  this  direction,  it  appears  culpable  to  allow  a  child  to  grow  up  surrounded 
by  the  undoubted  dangers  which  attend  the  possession  of  a  constricted  chest. 

It  will  be  observed  from  the  above  tables  that  a  great  increase  in  the 
circumference  of  the  chest  can  take  place  as  an  almost  solitary  feature  of 
development.  Mr.  Maclaren  gives  the  case  of  a  lad  of  nineteen  whose  heiglit 
was  not  increased  by  systematic  exercise,  but  who  increased  the  girth  of  his 
•chest  by  4^  inches  in  nine  months. 

It  is  well  also  to  note  that  an  improvement  in  the  measurements  of  the 
chest  can  be  effected  many  years  after  the  period  of  youth  is  passed.  Thus 
Maclaren  cites  the  case  of  a  gentleman  aged  thirty-five  who  at  the  end  of  two 
months'  exercise  at  the  Oxford  Gymnasium  had  increased  the  circumference 
of  his  thorax  by  no  less  than  4^  inches.  His  height  was  diminished  by  an 
eighth  of  an  inch,  due  probably  to  an  increase  in  the  curvature  of  the  thoracic 
part  of  the  spine. 

In  considering  the  general  question  of  increase  in  chest  girth  care  must 
be  taken  not  to  ascribe  this  increase — as  some  appear  inclined  to  do — entirely 
to  an  increase  in  the  capacity  of  the  thoracic  cavity.  This  is  probably  in  all 
cases  of  much  less  effect  than  muscular  development.  Those  who  practise 
•excessively  with  gymnastic  apparatus  acquire  a  peculiar  conformation  of  the 
chest,  the  main  factor  in  which  is  certainly  not  an  increase  in  the  capacity  of 
the  thorax. 

2.  The  Proportions  of  the  Body. — A  proper  physical  training  does  some- 
thing more  than  merely  increase  the  size  of  the  limbs  and  possibly  the  height 
of  the  body.  It  tends  to  render  all  parts  of  the  body  symmetrical  and  more 
perfectly  proportioned. 

A  well-proportioned  body  has  a  grace  which  is  independent  of  mere  size, 
height,  and  strength.  It  is  in  women  especially  that  the  great  lack  of  a  per- 
fect proportion  is  so  often  conspicuous.  In  one  the  hips  are  out  of  propor- 
tion to  the  shoulders  ;  in  another  the  width  of  the  chest  is  totally  out  of 
•keeping  with  the  height  of  the  body ;  in  a  third  the  length  of  the  upper 
limbs  is  not  in  proportion  to  the  dimensions  of  the  trunk. 

Those  who  have  taken  properly  arranged  exercise  from  their  earliest 
youth  may  still  need  many  graces,  but  they  will  probably  possess  the  peculiar 
grace  which  belongs  to  a  symmetrical  body. 

Of  all  animals  man  is  the  most  subject  to  variations  in  proportion  and 
in  symmetry.  It  is  certain  that  in  some  children  the  body  develops  unevenly  : 
one  side  appears  to  be  larger  than  the  other  ;  one  limb  may  be  longer  than 
its  fellow  ;  one  side  of  the  thorax  may  be  of  greater  circumference  than  the 
other.  Such  deviations — which  in  no  sense  constitute  deformity — a  well- 
directed  system  of  physical  training  may  correct. 

It  is  common  to  meet  a  long,  lanky  lad  with  spider-like  arms  and  legs, 
a  meagre  neck,  and  a  narrow  chest.  It  is  probably  said  that  he  has  '  out- 
grown his  strength.'  In  reality  his  growth  in  height  has  been  out  of  pro- 
portion to  his  growth  in  muscular  power.  With  proper  training  such  a  lad 
ceases  to  be  lanky  ;  he  becomes  merely  tall,  his  chest  fills  out,  his  arms 
acquire  a  greater  girth,  his  neck  becomes  sinewy,  and  the  '  scarecrow  '  of  the 
schoolroom  becomes  possibly  a  lithe,  well-proportioned  youth. 

Another  lad  may  be  squat  and  '  stumpy  '  and  heavy-looking.  He  has  a 
big  head  and  a  wide  chest  and  limbs  which  appear  to  be  ridiculously  out  of 
proportion  to  his  burly  trunk.  He  begins  to  pursue  every  available  form  of 
exercise  and  outdoor  recreation,  and  in  a  few  years  he  has  sprung  up.  His 
wide  chest  has  stood  him  in  good  stead,  and  his  limbs  are  now  no  longer  out 
of  keeping  with  his  body. 


550  HYGIENE 

The  following  account  of  tlie  normal  proportions  of  the  body  is  founded^ 
upon  that  given  by  Mr.  Roberts  in  his  '  Manual  of  Anthropometry.' 

The  Head. — Of  all  parts  of  the  body,  the  head  varies  least  in  its  propor- 
tions during  growth.  In  the  average  adult  it  is  considered  to  form  the  seventh 
part  of  the  whole  height.  From  birth  to  the  period  of  full  development  the 
head  only  doubles  its  height,  while  the  whole  body  elongates  three  or  four 
times  its  original  dimensions.  The  most  active  growth  of  the  head  is  during 
the  first  two  years  of  life.  The  lower  parts  of  the  face  grow  at  a  greater  rate 
than  the  upper,  and  all  the  horizontal  measurements  of  the  head  develop  less 
than  those  of  height. 

TJie  Trunk. — The  height  of  the  neck  increases  irregularly.  The  most 
rapid  growth  is  at  puberty.  The  neck  ultimately  attains  to  double  its  original 
dimensions.  The  other  parts  of  the  body  increase  with  greater  energy,  and 
growth  is  greater  the  further  the  parts  are  situated  from  the  summit  of  the 
head.  Thus,  while  the  measurements  of  the  head  and  neck  are  only  doubled, 
those  of  the  trunk  are  tripled,  and  those  of  the  lower  extremities  are  more 
than  quadrupled.  The  transverse  diameters  of  the  trunk  increase  nearly  in 
the  same  ratio  as  the  height.  They  triple  from  birth  to  the  period  of  full 
development.  At  the  age  of  six  or  seven,  this  diameter  is  already  doubled. 
The  antero-posterior  diameter  of  the  thorax  increases  less  rapidly  and  is  not 
doubled  until  about  puberty. 

At  the  time  of  birth,  when  the  child  is  about  the  sixth  of  the  height  it 
will  ultimately  attain  to,  the  point  which  di\-ides  the  total  height  into  two- 
equal  parts  is  a  little  above  the  navel ;  at  two  years  of  age  it  is  at  the  navel ; 
at  three  years,  when  the  child  has  attained  half  its  total  height,  the  central 
point  is  on  a  line  with  the  upper  borders  of  the  iliac  bones  ;  at  ten  years  of 
age,  w4ien  the  child  has  attained  three-fourths  of  its  total  height,  the  central 
point  is  on  a  line  with  the  trochanters  ;  at  thirteen  years  it  is  at  the  pubes, 
and  in  the  adult  man  it  is  nearly  half  an  inch  lower.  In  the  adult  woman 
the  central  point  is  a  little  above  the  pubes. 

The  Upper  Limbs. — The  space  covered  by  the  arms  extended  horizontally 
is  equal  to  the  total  height  of  the  body,  from  birth  to  puberty. 

In  the  adult  man  the  ratio  of  the  height  to  the  measurement  of  the  ex- 
tended arms  is  as  1  to  1-045  ;  and  in  the  adult  woman  as  1  to  I'OIS.  The 
length  of  the  arm — excluding  the  hand — is  doubled  at  the  age  between  four 
and  five  years,  tripled  between  thirteen  and  fourteen,  and  quadrupled  at  the 
period  of  full  development.  The  hand  develops  less  rapidly.  Afterthe  age 
of  seven  or  eight  the  length  of  the  hand  has  the  ratio  to  the  total  height  of 
one  to  nine.     This  apphes  to  adults  both  male  and  female. 

The  Lower  Limbs. — The  lower  extremities  in  adults  are  five  times  the 
length  they  were  at  birth.  They  double  their  length  before  the  third  year, 
and  at  twelve  they  are  four  times  their  original  length.  The  length  of  the 
thigh  varies  considerably  and  has  much  to  do  with  the  differences  in  the  total 
height  of  individuals.  The  foot  at  all  ages  of  life  and  in  both  sexes  forms 
from  the  0"15  to  0"1G  of  the  total  height  of  the  mdividual.  It  is  only  about 
the  age  of  ten  that  the  length  of  the  foot  is  equal  to  the  height  of  the  head. 
Before  that  period  the  head  is  the  longer,  and  after  it  the  shorter. 

The  perfect  Female  Form. — The  relative  proportions  of  a  perfect  female 
form  as  deduced  by  modern  sculptors  from  Greek  statues  have  been  given  as 
follows.  Her  height  will  be  five  feet  five  inches.  With  the  arms  extended 
the  measurement  from  finger-tip  to  finger-tip  should  be  equal  to  her  own 
height.  The  hand  should  be  i\,th  of  this,  the  foot  -jth,  and  the  chest  diameter 
-!th.  From .  her  perineum  to  the  ground  she  should  measure  just  what  she 
measures  from  the  perineum  to  the  top  of  the  head.  The  knee  should  be 
midway  between  the  perineum  and  the  heel. 


PHYSICAL  EDUCATION  551 

The  distance  from  the  elbow  to  the  middle  finger  should  be  the  same  as 
from  the  elbow  to  the  middle  of  the  chest.  The  head  should  be  about  the 
length  of  the  foot.  A  woman  of  this  height  should  measure  24  inches  about 
the  waist,  34  inches  around  the  chest  if  measured  under  the  arms,  and  43  if 
measured  over  them.  The  upper  arm  should  measure  13  inches  and  the 
wrist  6.  The  circumference  of  the  thigh  should  be  25  inches,  of  the  calf  of 
the  leg  14^  inches,  and  of  the  ankle  8  inches. 

In  determining  the  rate  of  growth  and  development  of  the  body  the 
following  system  of  measurements,  advised  by  Mr.  Maclaren  and  given  in  his 
well-known  work,  may  be  followed  out : — 

System  of  Measurements 

Heiqht  (without  boots).— The  position  of  attention,  the  heels  together,  the  knees 
braced  back,  the  chin  raised,  the  head  held  steady,  the  shoulders  square  to  the  front,  the 
heels,  hips,  shoulders,  and  head  touching  the  pillar  of  the  standard. 

N.B. — This  measurement,  when  repeated,  should  always  be  taken  at  the  same  time  of 
the  day,  and  after  the  same  amount  of  bodily  exertion. 

Weight. — In  working  costume,  i.e.  in  light  shoes,  flannel  trousers,  flannel  shirt  or 
jersey. 

N.B. — This  measurement  when  repeated  should  always  be  taken  at  the  same  time 
of  the  day,  and  with  reference  to  any  circumstance  which  would  affect  its  accuracy. 

Chest. — Over  the  jersey  or  naked  breast.  The  position  of  attention,  but  with  the  anns 
horizontally  extended,  the  palms  of  the  hands  held  upwards  and  open,  the  finger  straight. 
The  tape  should  be  passed  around  the  chest  in  the  line  of  the  nipple. 

N.B. — Care  must  be  taken  that  the  chest  is  not  inflated  beyond  its  usual  expansion 
during  ordinary  breathing.  Where  a  single  measurement  is  taken  the  above  hne  is  the 
best,  as  gauging  approximately  at  once  the  muscular  and  respiratory  capacity ;  but  when 
the  latter  quality  is  of  primary  importance  (as  in  rowing)  a  second  measurement  should 
be  taken  lower  down  the  chest,  the  tape  being  passed  over  the  ninth  rib. 

In  measuring  recruits  in  the  British  army,  the  man  stands  erect,  with  the  arms 
hanging  loosely  by  the  side.  The  lower  edge  of  the  tape  should  touch  the  nipple.  The 
man  is  required  to  count  ten  slowly  during  the  operation,  to  prevent  him  from  keeping 
his  lungs  over -inflated. 

Forearm  (skin  measurement). — The  arm  extended  as  in  the  preceding  measurement, 
but  with  the  hand  tightly  closed,  the  tape  to  be  passed  around  the  thickest  part  of  the 
arm,  and  its  girth  at  that  point  reckoned. 

N.B. — With  men  who  have  taken  little  exercise  this  line  will  always  be  found  near  the 
elbow  joint,  but  as  the  limb  becomes  developed,  and  the  numerous  muscles  of  the  forearm 
acquire  bulk  and  power  from  exercise,  the  greatest  girth  will  be  found  from  2  to  3  inches 
below  it.  Unless  this  circumstance  be  kept  in  view  the  actual  increase  will  not  be  per- 
ceived. 

Upper  arm  (skin  measurement). — The  hand  closed,  the  arm  bent  at  the  elbow,  and 
the  hand  brought  down  towards  the  shoulder.  This  should  be  slowly  and  gradually  done, 
bending  the  joints  of  the  fingers,  clenching  the  fist,  and  bringing  the  forearm  down  upon 
the  upper  arm,  the  tape  to  be  passed  in  a  straight  line  around  the  thickest  part  of  the 
arm. 

N.B. — When  the  whole  arm  is  fully  developed,  the  difference  in  size  between  the  fore 
and  upper  arm  in  an  adult  of  medium  stature  will  be  about  2  inches,  and  it  will  almost 
invariably  be  found  that  when  the  upper  arm  is  feeble  the  upper  region  of  the  chest  will 
be  feeble  also.  With  a  chest  of  40  inches  the  arm  would  probably  be  12  inches  and  14 
inches. 

Calf  (skin  measurement). — The  limb  to  be  held  stiff  and  straight,  the  heel  raised  from 
the  ground,  the  toes  pressed  strongly  down,  and  the  knee  braced  back.  The  tape  is  to  be 
passed  around  the  thickest  part  of  the  calf  ;  and  as  the  position  of  this  line  will  somewhat 
vary  with  different  men,  and  with  the  same  limb  in  different  stages  of  development,  one 
or  two  points  should  be  tried  and  that  which  shows  the  greatest  girth  selected. 

Thigh  (skin  measurement). — The  limb  placed  as  in  preceding  measurement,  the  tape 
to  be  passed  in  a  horizontal  line  around  the  thickest  part  of  the  limb,  which  will  be  at 
the  highest  point  of  the  thigh  admitting  of  horizontal  measurement. 


552  HYGIENE 


2.  The  Effect  of  Exercise  upon  the  Muscular  and  Nervous 

Systems 

Of  the  exact  changes  which  take  place  in  active  muscle,  and  of  the 
circumstances  attending  muscular  contraction,  it  is  needless  to  deal  at  any 
length.     The  matter  is  fully  considered  in  every  text-book  of  physiology. 

The  following  brief  account  of  the  metabolism  in  nuiscle  may  be  given. 
In  an  active  muscle  the  blood-vessels  are  dilated.  The  neutral  or  feebly 
alkaline  reaction  of  the  passive  structure  becomes  an  acid  reaction  when  the 
muscle  is  contracting,  owing,  it  is  supposed,  to  the  formation  of  paralactic 
acid.  A  considerable  quantity  of  carbon  dioxide  is  excreted  from  the  active 
muscle,  while  a  large  proportion  of  oxygen  is  consumed.  The  amount  of 
glycogen  and  grape  sugar  is  diminished  in  an  active  muscle,  the  tissue  of 
which  contains  less  extractives  soluble  in  water,  but  more  extractives  soluble 
in  alcohol.  During  exercise  the  amount  of  water  in  muscular  tissue  increases, 
while  that  of  the  blood  is  diminished  in  proportion.  Heat  is  formed  in  a 
muscle  in  a  state  of  activity. 

Turning  to  more  general  matters  concerning  the  muscular  system,  it  has 
been  well  said  that  '  function  makes  structure,'  and  it  is  certain  that  muscular 
exercise  makes  muscular  tissue.  Not  only  is  the  exercised  muscle  increased  in 
size,  both  as  a  whole  and  as  far  as  its  individual  parts  are  concerned,  but  there 
is  eliminated  from  it  such  tissue  as  is  other  than  muscular.  The  fat  contained 
among  its  meshes  is  reduced  to  a  minimum,  the  connective  tissue  is  lessened 
in  amount,  the  aponeurotic  parts  are  strengthened,  and  the  structure  of  the 
muscle  is  so  amended  that  it  is  hampered  by  no  material  other  than  that 
concerned  in  actual  movement.  It  is  freed,  moreover,  of  such  nitrogenous 
substances  as  are  capable  of  giving  rise  to  superabundant  waste  products  of 
combustion. 

There  is  a  limit,  of  course,  to  the  growth  of  muscles,  and  muscles  exer- 
cised to  too  great  an  extent  will,  after  attaining  a  certain  size,  commence  to 
waste.  The  contractile  force  of  the  muscle  is  increased  and  an  improvement 
takes  place  in  those  conditions  which  insure  the  speedy  and  complete  con- 
traction of  its  fibres.  It  has  been  pointed  out  that  the  muscles  of  an  athlete 
when  in  training  contract  with  extraordinary  force  under  the  electric  current : 
the  muscular  sense  is  developed  to  its  utmost,  and  the  circumstances  in- 
volved in  the  performance  of  a  reflex  act  are  placed  under  improved  conditions  ; 
the  power  of  co-ordination  possessed  by  the  individual  is  augmented ; 
he  acquires  the  art  of  causing  muscles,  which  may  be  said  to  have  been 
hitherto  estranged,  to  act  in  concert,  so  that  movements  which  were  com- 
plex and  effected  with  difficulty  are  ultimately  carried  out  with  ease.  In  this 
way  the  nervous  system  is  saved  a  great  expenditure  of  force.  Acts  which 
were  performed  with  effort  and  by  conscious  will  become  automatic,  and  there 
is  a  saving  in  the  expenditure  of  active  force  in  the  spinal  cord  and  m  the 
cerebral  cortex.  Complicated  movements  become  '  organically  registered  in 
the  brain  '  and  cease  to  be  difficult.  One  conspicuous  feature  in  muscular 
training  is  the  increase  in  the  possibilities  of  automatism.  As  time  goes  on, 
and  the  individual  practises  more  and  more,  he  finds  the  work  become  easier 
and  easier.  This  depends,  not  only  upon  an  increase  in  the  actual  strength 
of  the  parts,  but  upon  the  greater  ease  with  which  the  muscles  concerned  act 
in  co-ordination  and  upon  the  muscular  experience  of  the  individual,  which 
prevents  him  from  misplacing  his  strength,  and  enables  him  to  attain  a  desired 
end  with  the  minimum  amount  of  force. 

He  who  is  beginning  to  practise  any  muscular  exercise,  such  as  fencing, 


PHYSICAL  EDUCATION  553 

bicycling,  or  rowing,  will  I'eel  that  he  moves  stiffly.  The  constant  connnont 
of  the  instructor  in  physical  exercises  is,  '  Don't  keep  so  stiff !  '  '  Let  your 
arms  go  loose  !  '  The  beginner  has  not  yet  learnt  how  to  balance  one  set 
of  muscles  against  their  antagonists.  His  movements  are  at  first  very 
deliberately  planned,  but  in  time  the  will  ceases  to  concern  itself.  A  memory 
is  developed  in  the  spinal  cord  and  in  the  muscular  centres,  and  one  great 
element  of  fatigue  is  removed. 

Nothing  in  physical  training  is  more  remarkable  than  the  economy  of 
force  which  results  from  muscular  education.  The  well-trained  athlete, 
moreover,  acquires  the  art  of  using  his  respiratory  muscles  with  the  greatest 
■economy.  He  does  not  exhaust  himself  with  needlessly  vigorous  breathing  ; 
he  learns  to  precisely  regulate  his  respiratory  movements  to  his  immediate 
needs,  and  he  brings  the  muscles  of  his  thorax  into  co-ordination  with  the 
■other  muscles  which  he  employs. 

Just  as  muscles  increase  with  use  and  waste  with  disuse,  so  the  whole  nerve 
apparatus  concerned  in  movement  is  structurally  improved  by  systematic 
exercise.  The  athletic  man  has  better  developed  nerves,  a  more  elaborate 
organisation  of  his  spinal  cord  and  of  certain  parts  of  his  brain,  than 
has  the  individual  whose  muscular  system  is  imperfectly  formed.  Just  as  a 
certain  segment  of  the  spinal  cord  and  of  the  cerebral  cortex  wastes  after  the 
removal  of  a  limb,  so  it  may  be  inferred  that  those  parts  become  hyper- 
irophied  and  elaborated  when  the  limb  in  question  is  unusually  employed. 

'  The  differences,'  writes  Sir  Crichton  Browne,  '  which  we  notice  between 
man  and  man  in  deportment,  gait,  and  expression  are  but  the  outward  and 
visible  signs  of  individual  variations  in  the  development  of  the  motor  centres 
■of  the  brain  ;  and  the  stammerings,  grimacings,  twitchings,  and  antics  which 
are  so  common  and  annoying,  alike  to  those  who  suffer  and  who  witness 
them,  are  probably  in  many  instances  the  effects  of  neglected  education  of 
some  of  those  centres,  and  might  have  been  abolished  by  timely  drill  and 
•discipline.' 

He  who  has  been  well  trained  physically  possesses  not  only  a  complete 
but  an  intelligent  use  of  his  muscles.  His  movements  are  powerful,  are 
under  absolute  control,  are  precise,  and  capable  of  the  finest  and  most 
elaborate  adjustment. 

The  art  of  the  athlete  consists,  not  in  employing  the  greatest  amount  of 
power  in  effecting  a  movement,  but  in  carrying  out  that  movement  with  the 
least  possible  expenditure  of  force.  The  tyro  at  cycling  will  use  an  amount 
of  muscular  force  in  riding  a  mile  which  would  probably  carry  an  experienced 
rider  some  twenty  miles. 

3.  The  Effect  of  Exercise  upon  the  Tissues  and  Organs  generally 

It  is  needless  in  this  place  to  deal  with  the  subject  of  bodily  heat,  with 
the  manner  in  which  it  is  developed  and  employed,  with  the  conditions  which 
regulate  it  and  attend  its  disposal.  It  is  necessary  only  to  say  that  in  the 
body  work  and  heat  are  always  associated,  and  it  is  believed  that  the  heat  is 
the  cause,  and  not  the  effect,  of  the  work.  No  muscular  contraction  can 
occur  without  the  production  of  heat,  but  of  the  precise  manner  in  which 
heat  acts  upon  muscle  and  makes  it  contract  little  is  known. 

Commenting  upon  this  matter  Dr.  Lagrange,  in  his  work  on  '  The 
Physiology  of  Bodily  Exercise '  (page  37),  observes :  '  Heat  causes  in 
muscular  fibres  the  first  stage  of  contraction,  or  at  least  an  aptitude  for 
coming  into  action  more  quickly  under  the  influence  of  the  will.  A  heated 
muscle  seems  to  have  stored,  in  a  sense,  a  latent  force.     It  has  been  ascer- 


554  HYGIENE 

tained  that  the  maximum  aptitude  for  contraction  is  exhibited  by  human 
muscles  at  about  40°  C.  It  follows  that  a  man  whose  muscles  are  at  this 
temperature  is  able  to  act  more  quickly,  and  at  once  can  make  use  of  all  his 
force. 

'  A  bodily  exercise  is  performed  with  more  vigour  and  ease  when  heat  has 
raised  the  temperature  of  the  muscles.  This  fact  is  so  well  known  that  there 
are  characteristic  phrases  to  express  it  in  common  speech.  We  say  of  a 
man  beginning  an  exercise  of  strength  or  skill  whose  movements  have  not 
yet  acquired  all  their  force  and  precision,  that  he  has  not  yet  warmed  to  his 
work.' 

The  author  compares  the  preliminary  canter  before  a  race,  the  preliminary 
sparring  before  a  fight,  and  the  strange  movements  of  an  angry  animal  before 
an  attack,  to  the  heating  up  of  a  locomotive.  It  may  be  pointed  out,  also,  that 
there  is  a  greater  aptitude  for  bodily  exercises  in  summer  than  in  winter,  and 
that  muscular  action  becomes  temporarily  paralysed  by  great  cold. 

The  heat  produced  in  the  body  depends  upon  certain  chemical  changes  in 
the  tisssues,  certain  combustions  which  are  mostly,  but  not  exclusively, 
oxidations.  These  products  of  combustion,  or  of  dissimilation,  examples  of 
which  are  afforded  by  carbon  dioxide,  urea,  uric  acid,  &c.,  are  noxious  to  life 
and  must  be  ejected  from  the  body  in  one  way  or  another  through  the  agency 
of  special  organs.  The  effects  produced  by  an  excess  or  by  a  retention  of 
these  products  are  dealt  with  in  discussing  the  subject  of  fatigue. 

Muscular  exercise  tends,  moreover,  to  remove  any  accumulation  of  fat 
which  may  exist  in  the  tissues.  Fat  is  the  type  of  what  are  known  as  the 
reserve  tissues.  It  serves  the  part  of  fuel  for  combustion ;  it  undergoes 
dissimilation  with  remarkable  ease,  and  may  therefore  be  regarded  as  fuel  of 
a  most  combustible  character.  As  fat  forms  no  permanent  structural  part 
of  the  organism,  its  removal  is,  within  limits,  effected  with  no  incon- 
venience. The  fat  man  who  takes  exercise  ffnds  that  he  soon  becomes 
breathless  and  fatigued.  His  unwonted  muscular  exertion  involves  a  great 
series  of  combustion  processes.  Fat  would  appear  to  be  of  all  substances 
the  one  W'hich  most  readily  lends  itself  as  material  for  such  changes.  The 
result  is  that  in  the  corpulent  individual  the  products  of  dissimilation  are 
produced  in  excess,  and  he  becomes,  in  a  certain  sense,  poisoned  by  the 
accumulation  of  these  products  (see  chapter  on  Fatigue  ).  He  is  hampered 
also  by  the  unnecessary  weight  of  his  body,  by  his  feeble  muscles,  and 
possibly,  to  some  extent,  by  the  mechanical  obstacles  offered  by  collections 
of  fat.  A  corpulent  man  in  rowing  finds  that  his  large  abdomen  is  an 
actual  mechanical  obstacle  in  the  way  of  his  movements. 

A  fat  man  when  in  training  loses  his  fat.  As  he  becomes  thinner  he 
becomes  stronger,  his  muscles  act  better,  he  is  less  breathless  on  exertion, 
less  fatigued  after  long-continued  effort,  and  may  in  time  reach  that  excellent 
state  of  health  known  as  '  good  condition.' 

The  fat  disappears  first  from  the  limbs,  especially  from  the  limbs  which 
are  particularly  employed.  Last  of  all  the  internal  accumulations  disappear, 
and  the  last  feature  to  go  will  probably  be  the  large  abdomen,  which  is  so 
terrible  a  trial  to  would-be  athletes  of  middle  age. 

It  may  here  be  said  that  the  deposit  of  a  certain  amount  of  fat  within  the 
abdomen  is  a  common  accompaniment  of  advancing  age,  and  that  its  forma- 
tion can  best  be  prevented  by  exercise,  and  especially  by  such  exercises  as 
involve  the  contraction  of  the  abdominal  muscles.  It  is  exceedingly  rare  to 
see  a  waterman  who  keeps  up  a  good  style  of  rowing  present  an  unduly 
prominent  abdomen. 

Exercise,  moreover,  tends  to  improve  the  condition  of  the  tissues  generally.. 


PHYSICAL  EDUCATION 


Tlie  soft  parts  become  firmer,  more  resistant,  less  easily  bruised  when 
damaged,  and  in  all  respects  sounder.  A  man  in  training  is  said  to  be  '  hard,' 
and  it  is  well  known  that  no  moderate  blow  will  raise  a  bruise  upon  the 
person  of  a  prize  fighter  when  he  is  in  perfect  '  condition.'  The  general 
standard  of  the  nutritive  activity  of  the  body  is  improved.  The  stout  and 
flabby  man  becomes  thinner,  harder,  and  firmer  under  training. 

The  thin  and  spare  man,  on  the  other  hand,  often  becomes  stouter  under 
training.  He  feels  better,  eats  better,  and  his  powers  of  nutrition  are  so 
improved  that  he  gains  flesh  and  weight. 

Thus  training  may  cause  one  man  to  lose  weight  and  another  to  gain  it,. 
and  both  to  look  healthier  and  better  for  the  change. 

As  Dr.  Lagrange  well  expresses  it,  '  Exercise  produces  in  the  system  two 
absolutely  different  effects :  it  increases  the  process  of  assimilation,  thank& 
to  which  the  body  gains  new  tissues,  and  it  accelerates  the  process  of  dissi- 
milation, which  leads  to  the  destruction  of  certain  materials.'  Its  action  in 
the  former  direction  depends  upon  the  increased  amount  of  oxygen  intro- 
duced into  the  system  by  the  improved  circulation  and  respiration  and  by  the 
healthy  stimulation  of  the  various  active  organs  of  the  body. 

The  need  for  exercise  is  felt  as  much  by  thin  people,  who  assimilate  too 
little,  as  by  fat  people,  who  do  not  dissimilate  enough.  Exercise  may  there- 
fore be  regarded  as  a  great  regulator  of  nutrition. 

As  the  action  of  the  heart  rapidly  increases  in  force  and  frequency 
during  exercise,  the  flow  of  blood  through  all  parts  of  the  body  is  increased. 
The  amount  of  increase  is  from  ten  to  thirty  beats,  but  it  may  be  more.  The 
skin  becomes  red  with  the  blood  contained  in  the  full  capillaries  and  perspira- 
tion is  much  increased.  The  amount  of  fluid  which  is  lost  by  the  skin  is 
very  considerable. 

The  digestive  apparatus  is  stimulated  and  strengthened  by  exercise.  The 
appetite  improves,  digestion  is  more  complete,  absorption  more  rapid,  and  the 
circulation  through  the  liver  is  more  vigorous  and  even. 

Muscular  exercises,  especially  such  as  employ  the  muscles  of  the  abdomen, 
have  a  very  beneficial  effect  upon  the  bowels,  promoting  peristaltic  movements 
and  reUeving  such  constipation  as  depends  upon  the  torpidity  of  the  intestine. 

One  other  conspicuous  effect  of  exercise  is  the  increased  elimination  of 
carbon.  This  is  eliminated  mainly  by  the  lungs.  The  observations  of 
Pettenkofer  and  Voit  give  the  following  results  : — 

Table  IX. 


- 

■ 

Absorption  of 
oxygen  in 
grammes 

Elimination  in  grammes  of 

Rest  day  . 
Work  day- 

708-9 
954-5 

Carbonic  acid 

911-5 

1284-2 

Water 

828-0 

2042-1 

Urea 
37-2 
37-0 

Excess  on  work  day 
(with  exeeption  of 
urea)     . 

246-6 

372-7 

1214-1 

-0-2 

It  is  demonstrated  that  a  considerable  formation  of  carbonic  acid  takes 
place  in  the  muscles.  As,  moreover,  exercise  is  clearly  necessary  for  a  suffi- 
cient elimination  of  carbon  from  the  body,  it  is  needful  in  a  condition  of  pro- 
longed rest  that  the  amount  of  carbon  in  the  food  be  lessened  to  avoid  an 
accumulation  of  that  element  in  the  tissues. 


556  HYGIENE 

With  regard  to  the  vexed  question  of  the  elimination  of  nitrogen  from 
the  body  during  exercise,  Parkes  condudes  his  careful  examination  of  the 
subject  in  these  words  : — 

*  On  the  whole,  if  I  have  stated  the  facts  correctly,  the  efl'ect  of  exercise 
is  certainly  to  inlluence  the  elimination  of  nitrogen  by  the  kidneys,  but  within 
various  limits,  and  the  time  of  increase  is  in  the  period  of  rest  succeeding 
the  exercise ;  while  during  the  exercise  period  the  evidence,  though  not 
certain,  points  rather  to  a  lessening  of  the  elimination  of  nitrogen. 

*  It  would  appear  from  these  facts  that  well-fed  persons  taking  exercise 
would  require  a  little  more  nitrogen  in  the  food,  and  it  is  certain,  as  a  matter 
of  experience,  that  persons  undergoing  laborious  work  do  take  more  nitro- 
genous food.     This  is  the  case  also  with  animals.' 

Dr.  Parkes  thus  sums  up  the  action  of  exercise  upon  the  kidneys  :  '  The 
water  of  the  urine  and  the  chloride  of  sodium  often  lessen  in  consequence 
of  the  increased  passage  from  the  skin.  The  urea  is  not  much  changed. 
The  uric  acid  increases  after  great  exertion,  so  also  apparently  the  pig- 
ment ;  the  phosphoric  acid  is  not  augmented  ;  the  sulphuric  acid  is  moderately 
increased ;  the  free  carbonic  acid  of  the  urine  is  increased  ;  the  chlorides  are 
lessened  on  account  of  the  outflow  by  the  skin ;  the  exact  amount  of  the 
bases  has  not  been  determined,  but  a  greater  excess  of  soda  and  potash  is 
eliminated  than  of  lime  or  magnesia.  Nothing  certain  is  known  as  to 
hippuric  acid,  sugar,  or  other  substances.' 

4.  The  Effect  of  Exeecise  upon  Pbesonaij  Comeliness  and  Comfort 

We  have  already  noted  the  effect  a  systematic  training  may  have  upon  the 
growth  and  development  of  the  body,  upon  the  size  of  the  chest,  and  the 
proportions  of  the  limbs.  Such  training,  moreover,  can  give  an  upright  and 
symmetrical  figure  and  an  easy  and  graceful  carriage.  There  is  a  swing 
about  the  body  and  a  bearing  of  the  head  and  shoulders  which  mark  those 
whose  muscular  system  has  been  fully  developed. 

Under  proper  training  the  shuffling  and  shambling  gait  disappears,  the 
loutish  boy  ceases  to  look  loutish,  and  the  gawky  girl  no  longer  excites  com- 
ment ;  rounded  shoulders  become  square  and  bending  backs  are  made  straight. 

The  athlete,  so  far  as  his  body  and  his  personal  equation  are  concerned, 
has  reached  the  full  and  perfect  stature  of  a  man,  and  the  girl  whose 
physical  education  has  been  complete  reaches  her  point  of  physical  perfection 
as  a  woman.  The  beauty  of  the  body  depends  upon  a  fully  formed  skeleton 
and  perfectly  developed  muscles,  and  not  upon  deposits  of  fat.  The  arm  of 
a  plump  but  ill-developed  woman  is  rounded  and  free  from  conspicuous  pro- 
minences about  the  elbow,  but  the  outline  is  as  meaningless  and  as  unnatural 
as  the  part  is  flabby  and  lifeless.  The  arm  of  a  woman  in  perfect  physical  con- 
dition has,  on  the  other  hand,  an  exquisite  outline.  It  presents  the  contour  given 
it  by  the  muscles  that  move  the  limb.  The  graceful  configuration  of  these 
muscles  has  not  been  hidden  beneath  a  monotonous  layer  of  fat.  The  arm  has 
an  individuality  and  has  reached  the  perfection  of  its  growth.  The  beauty 
of  the  right  arm  of  many  female  violinists  is  a  matter  of  common  comment. 

Unfortunately  there  is  comparatively  little  fat  about  joints,  and  the  most 
trying  feature  in  the  feebly  developed  woman  is  a  bony  elbow.  There  are 
masses  of  muscle  about  the  elbow,  and  if  these  are  wasted  the  details  of  the 
skeleton  become  unpleasantly  conspicuous.  If  they  are,  on  the  contrary, 
Avell  developed,  the  contour  of  the  elbow  becomes  even  and  graceful.  The 
arm  of  an  individual  who  is  not  only  thin  but  is  also  ill- developed  is  an  un- 
pleasant spectacle — it  is  a  burlesque  of  a  human  limb. 


PHYSICAL  EDUCATION  557 

In  the  neck  and  the  upper  part  of  the  chest  the  effects  of  a  sound  physical 
traimng  are  very  conspicuous.  The  long  turkey-hke  neck  of  the  ill-developed 
lad  and  the  scraggy  neck  of  the  ill-nurtured  woman  are  familiar  enough. 
They  are  both  unnecessary  disfigurements. 

A  perfectly  shaped  thorax  gives  to  the  human  figure  its  most  striking 
feature,  and  such  a  chest  cannot  be  met  with  among  those  whose  physical 
education  has  been  quite  neglected.  There  is  little  excuse  for  an  ill-formed 
thorax,  and  yet  at  the  present  day  it  is  met  with  on  all  sides  and  in  all  classes 
of  the  community. 

The  back  of  the  ill-developed  is  characteristic.  The  spinous  processes  of 
the  vertebrae,  instead  of  being  sunk  in  a  median  groove  formed  by  the  two 
great  masses  of  the  vertebral  muscles,  stand  out  in  the  form  of  an  irregular 
nodulated  ridge.  The  back  looks  feeble,  lifeless,  wasted,  and  there  is  an  air 
of  muscular  pauperism  about  it.  It  looks  poor,  and  yet  it  must  be  owned 
that  it  is  the  type  of  back  very  commonly  met  with  among  the  favoured  classes, 
and  especially  among  the  women. 

The  tissues  of  the  ill-developed  are  flabby,  doughy,  baggy.  They  lack 
elasticity  and  consistence.  The  cheek  of  the  overworked  shop  assistant  who 
gets  no  real  exercise  can  be  seen  to  shake  as  he  walks  along  the  street. 

The  purposeless-looking  extremities  of  those  who  are  physically  un- 
educated are  well  known.  They  have  the  appearance  of  the  limbs  of  indi- 
viduals who  are  recovering  from  serious  illness.  They  are,  as  a  matter  of 
fact,  the  extremities  of  persons  who  have  never  been  well. 

The  tissues  of  the  well-developed  are  firm,  elastic,  resisting,  active,  and  full 
of  evidence  of  living.  There  is  given  to  every  part  of  the  surface  of  the  body 
that  rapid  change  in  contour  and  that  indescribable  aspect  of  vigour  and 
soundness  which  are  features  of  a  healthy  and  well-knit  frame. 

In  the  above  comments  I  am  alluding  merely  to  the  results  of  a  systematic 
physical  training,  and  not  to  such  exceptional  results  of  muscular  exercise 
as  produce  professional  gymnasts  and  acrobats. 

Undue  and  unsymmetrical  muscular  development  may  deform  the  body  ; 
a  circumstance  well  illustrated  by  some  acrobats,  whose  lower  limbs  are  of 
normal  or  sub-normal  development,  while  their  arms  are  enormous,  their- 
shoulders  mountainous  and  uncouth,  their  necks  coarse  and  bullock-hke,  and 
the  upper  part  of  the  back  arched  or  bowed.  This  is  especially  noticeable  in 
gymnasts  who  practise  upon  the  trapeze,  horizontal  bar,  and  other  apparatus, 
and  who  have  exclusively  developed  the  muscles  of  the  upper  half  of  the  trunk.. 

The  skin  of  those  who  have  taken  pains  to  bring  their  bodies  to  perfection 
often  compares  in  a  marked  manner  with  the  integument  of  the  neglected 
and  uneducated.  It  is  firm,  clear,  and  wholesome.  It  is  not  to  be  argued 
that  exercise  will  keep  the  integument  free  from  marks  and  blotches,  and  render 
a  naturally  coarse  skin  fine,  but  it  will  bring  about  such  differences  in  appear- 
ance as  serve  to  distinguish  what  is  healthy  from  what  is  unsound.  The 
delicate  and  sensitive  complexion  of  a  young  woman  whose  physical  training 
has  been  efficient  is  in  conspicuous  contrast  with  the  dull,  loose,  lustreless 
integument  of  the  abstainer  from  muscular  pursuits.  'The  skin  of  the 
recluse  is  grey,  greasy,  and  unpleasant-looking.  The  complexion  of  the 
young  man  about  town  is  almost  distinctive.  It  is  aggressively  unwholesome, 
and  forms  a  contrast  with  that  of  his  companion  who  has  just  returned  from 
a  shooting  expedition  or  a  long  boating  tour.  Exercise,  of  course,  involves 
more  living  in  the  open,  a  freer  and  deeper  respiration,  and  the  coursing  of  a 
more  vigorous  flow  of  blood  through  the  integuments  ;  it  leads  actually  to  a 
sounder  state  of  the  general  health,  and  such  improvement  is  at  once  evident 
upon  the  skin.     There  is  a  certain  brightness  and  vivacity  of  the  look,  and  a. 


558  HYGIENE 

certain  degree  of  self-assertion  iu  the  carriage,  of  those  wlio  are  in  sound 
physical  condition.  They  contrast  with  the  wan,  hopeless-looking  creatures 
who  never  '  stir  out  of  the  house,'  and  who  crawl  through  life  in  a  semi- 
apologetic  manner. 

In  the  matter  of  personal  comfort  no  greater  sense  of  pure  pleasure  can 
influence  the  human  mind  than  that  which  results  from  perfect  health. 
There  is  the  glorious  delight  of  movement  and  of  vigorous  activity,  quite 
apart  from  the  excitement  and  mental  enjoyment  wliich  attend  so  many 
recreations  and  outdoor  sports.  The  lad  Avho  is  m  perfect  physical  condition 
wakes  up  in  the  morning,  fresh  and  rampant ;  and  if  it  be  the  summer  time  he 
probably  feels  an  irresistible  impulse  to  dash  out  into  the  open  air  and  fill 
his  lungs  and  quicken  his  pulse  and  move  his  muscles.  Even  the  fatigue 
that  comes  over  a  man  who  is  in  good  condition,  and  who  has  taken  a  long 
spell  at  exercise,  is  pleasurable.  Such  a  one  eats  well  and  digests  well ; 
the  functions  of  his  body  are  carried  on  normally,  and  he  experiences  to  its 
full  the  delight  of  living. 

The  youth  who  takes  no  exercise,  who  is  always  poring  over  his  books, 
misses  at  least  one-half  of  the  enjoyments  which  are  available  to  man  during 
a  comparatively  short  life.  He  is  a  dull  creature,  dyspeptic  probably,  the 
subject  of  headaches,  constipation,  and  many  minor  ills.  To  him  joy  cometh 
not  in  the  morning,  and  in  the  place  of  an  honest  fatigue  he  has  the  '  fidgets  * 
and  his  weariness  is  painful.  His  appetite  is  feeble  possibly,  his  circulation 
is  poor,  and  very  often  he  sleeps  badly,  and  can  envy  the  easy  and  profound 
sleep  of  a  companion  who  has  come  home  after  a  long  run  across  country. 
The  simplest,  the  purest,  and  the  pleasantest  recollections  in  hfe  usually  go 
back  to  certain  physical  enjoyments  in  the  open  air,  to  some  walking  tour  or 
cricket  match,  to  some  river  expedition,  or  to  some  great  day  upon  the  moors. 

When  sudden  exercise  is  forced  upon  the  undeveloped  individual,  he  is 
more  or  less  unable  to  meet  it ;  he  becomes  breathless,  perspires  violently,  is 
uncertain  of  himself,  is  clumsy  and  the  subsequent  victim  of  a  painful  degree 
of  fatigue.     Of  such  a  person  it  cannot  be  said — 

Yea,  this  iu  him  was  the  peculiar  grace, 
That  before  liviu"  he  learned  how  to  live. 


5.  The  Mental  akd  Moeal  Effects  op  Exekcise 

Moderate,  regular,  and  systematic  exercise  by  stimulating  the  circulation 
of  the  body  improves  also  the  circulation  of  the  brain,  and  is  therefore  an 
aid  to  cerebral  movements.  It  improves  the  health  and  the  physical  strength, 
and  so  increases  the  capability  of  the  individual  for  mental  work  and  for  the 
physical  strain  incident  upon  mental  concentration. 

By  organising  in  the  brain  a  series  of  muscular  movements,  by  elaborat- 
ing the  powers  of  co-ordination,  and  by  establishing  automatism  in  a  large 
and  varied  series  of  actions,  it  saves  actual  brain- work  and  renders  a  con- 
siderable number  of  movements  independent  of  the  direct  action  of  the 
will. 

It  offers,  too,  an  admirable  change  of  employment.  There  is  no  better 
rest  from  severe  mental  work  than  well-selected  bodily  exercise.  With  many 
men  to  lie  upon  a  beach  and  throAv  stones  into  the  water  is  no  rest.  They 
would  find  a  more  complete  repose  in  the  pleasurable  use  of  their  muscles, 
in  the  pursuit  of  some  congenial  outdoor  sport,  and  in  rendering  dormant 
the  energies  of  one  part  of  the  nervous  system  by  an  engrossing  employment 
of  another  part. 


PHYSICAL  EDUCATION  559 

Such  exercises  as  are  indulged  in  when  seeking  rest  from  mental  work 
must  be  simple  and,  so  far  as  possible,  such  as  are  automatically  performed. 

*  Prescribe  fencing,  gymnastics  with  apparatus,  and  lessons  in  a  riding 
school,'  writes  Dr.  Lagrange,  '  to  all  those  idle  persons  whose  brain  languishes 
for  want  of  work.  The  effort  of  will  and  the  work  of  co-ordination  which 
these  exercises  demand  will  give  a  salutary  stimulus  to  the  torpid  cerebral 
cells.  But  for  a  child  overworked  at  school,  for  a  person  whose  nerve-centres 
are  congested  owing  to  persistent  mental  effort  in  preparing  for  an  examina- 
tion, for  such  we  must  prescribe  long  walks,  the  easily  learnt  exercise  of 
rowing,  and,  failing  better,  the  old  game  of  leap  frog  and  prisoner's  base, 
running  games — anything,  in  fact,  rather  than  difficult  exercises  and  acro- 
batic gymnastics.' 

'  Mr.  Charles  Paget,  at  one  time  M.P.  for  Nottingham,  tried  in  the  village 
school  on  his  estate  at  Euddington  a  very  interesting  experiment.  He 
was  not  satisfied  with  the  general  progress  made  by  the  boys,  and  he 
provided  for  them  a  large  garden.  The  school  was  then  divided  into  two 
sections,  one  of  which  was  kept  to  the  ordinary  school  work  for  the  ordinary 
hours,  the  other  for  half  of  these  hours  only,  the  rest  of  the  school-time  being 
devoted  to  work  in  the  garden.  At  the  end  of  the  term  the  half  time,  or 
gardening  boys,  had  excelled  the  others  in  every  respect — in  conduct,  in  dili- 
gence, and  in  the  results  of  study  '  ('  Health  Exhibition  Manuals,'  vol.  xi. 
p.  327). 

There  must  be  a  proper  distribution  of  mental  and  physical  work.  Just 
as  '  all  work  and  no  play  makes  Jack  a  dull  boy,'  so  all  play  and  no  work 
makes  Jack  a  still  duller  boy. 

An  excessive  and  absorbing  indulgence  in  physical  exercises  is  un- 
doubtedly bad.  It  tends  to  make  the  individual  too  much  of  an  animal  and 
to  afford  neither  time,  opportunity,  nor  suitable  conditions  for  the  develop- 
ment of  his  brain.  Under  such  circumstances  even  the  body  tends  to  be- 
come stunted  if  the  practice  be  commenced  early,  and  the  lad  develops  not 
only  an  animal  look,  but  some  of  the  intellectual  and  emotional  attributes  of 
the  animal. 

Still,  on  the  other  hand,  in  these  days  of  cramming  and  intense  competi- 
tion, many  a  successful  man  has  to  thank  Providence  for  the  late  recognised 
blessings  of  an  idle  youth. 

The  systematic  and  properly  arranged  pursuit  of  physical  exercise  tends 
to  develop  certain  admirable  qualities,  and  notably  those  which  are  so  much 
prized  among  Englishmen,  and  which  are  well  designated  as  '  manly.' 

These  qualities  are  brought  out  in  those  who  are  enthusiasts  in  out- 
door sports  and  games.  The  football  player  has  done  more  than  merely 
develop  his  muscles  ;  the  man  who  has  rowed  in  his  college  eight  has  learnt 
something  beyond  the  mysteries  of  the  sliding  seat ;  and  the  experienced 
'  player '  at  almost  any  outdoor  game  has  been  improved  by  other  means 
than  those  which  the  actual  manoeuvres  of  the  game  demand.  Such  lads 
and  men  have  learnt  in  a  school  where  the  principles  of  pluck,  courage, 
endurance,  and  self-reliance  are  acquired.  They  have  probably  learnt  to  be 
ready,  to  be  quick  of  eye  and  hand,  and  prompt  in  judgment.  They  may 
have  appreciated  the  value  of  disciphne  and  of  self-control.  They  may  have 
felt  the  inspiration  of  the  chivalry  of  days  gone  by,  and  have  experienced 
the  influences  of  good  fellowship  and  loyal  comradeship.  They  may  have 
learnt  what  it  is  to  be  patient,  to  be  fair,  to  be  unselfish,  and  to  be  true. 

Many  a  man  who  in  later  life  finds  himself  in  a  dangerous  strait  would 
wish  for  no  one  better  by  his  side  than  the  lad  who  pulled  behind  him 
in  a  racing  eight.     The  cries  and  the  cheers  of  the  football  field  must  have 


5G0  HYGIENE 

given  heart  to  many  a  desperate  soldier  when  hard  pressed  in  the  turmoil  of 
actual  war,  and  a  sailor  can  say  no  more  gracious  thing  of  his  mate  than  that 
he  is  '  a  man  to  stand  by  you  in  a  gale.' 

There  is  a  certain  moral  effect  also  which  comes  with  a  sound  physical 
training.  The  schoolboy  who  is  foremost  in  athletic  exercises  will  probably 
be  found  to  be  more  open,  more  straightforward,  more  simple,  and  more 
Avholesome-minded  than  the  lad  who  spends  his  time  loafing  at  the  pastry- 
cook's. Mr.  Cathcart  in  his  '  Health  Lectures  '  (Edinburgh,  188-4)  brings  this 
point  well  forward  in  the  evidence  he  quotes  from  certain  head-masters  of 
large  public  schools  in  England.  One  head-master  writes  :  '  The  worst  boys 
intellectually,  physically,  and  morally  are  the  loafers,'  and  another  :  '  The 
boys  who  work  hard  and  play  hard  do  not  ape  the  vices  of  men,  and  are  free 
from  the  insidious  evils  that  often  fasten  on  unoccupied  boyhood.' 

I  think  it  may  be  safely  said  that  that  miserable  creature,  the  juvenile 
sexual  hypochondriac,  is  never  to  be  found  among  those  who  are  foremost 
at  athletics  and  outdoor  games. 

FATIGUE 

This  subject  will  be  considered  under  the  following  head?  :  1.  Breath- 
lessness  ;  2.  Muscular  Fatigue  ;  3.  Muscular.  Stiffness  ;  4.  General  Fatigue. 

1.  Beeathlessness 

The  breathlessuess  which  is  a  famihar  attendant  upon  exercises  of  a 
certain  character  has  received  but  little  notice  at  the  hands  of  physio- 
logists. Dr.  Lagrange  has  in  his  recent  work,  to  which  allusion  has  been 
already  made,  dealt  very  fully  with  the  subject,  and  explains  it  by  a  theory 
which  appears  to  be  both  sound  and  satisfactory.  The  phenomena  of  breath - 
lessness  are  familiar  enough.  One  has  but  to  picture  a  man  of  middle  age,, 
who  is  out  of  training,  and  who  has  set  himself  the  task  of  running  a  certain 
distance.  He  soonfeels  embarrassed  in  his  breathing ;  he  pants,  his  respiratory 
movements  become  jerky  and  irregular  ;  he  is  aware  of  a  terrible  sense  of 
oppression  in  his  chest,  a  sense  which  increases  with  each  step.  His  head 
throbs  ;  he  begins  to  find  that  his  strength  is  failing  him  ;  he  feels  that  he 
could  run  many  more  yards,  so  far  as  his  legs  are  concerned,  but  the  sense  of 
suffocation  arrests  him.  He  staggers  along,  his  steps  become  uncertain,  his 
face  haggard,  his  movements  irregular,  and  he  stops  at  last  dead  beat.  As 
he  rests  he  continues  for  many  minutes  to  breathe  in  the  same  troubled  way. 
The  man  is  said  to  be  '  blown,'  to  have  '  lost  his  wind.'  He  has  used  his 
legs,  but  his  legs  have  not  given  way.  It  is  his  chest  which  has  failed  him. 
This  constitutes  the  remarkable  feature  of  the  phenomenon.  The  same  man 
can  exercise  his  arms  with  dumb-bells  for  three  times  the  time  occupied  by 
the  run,  yet  he  is  not  '  out  of  breath.'  He  can  row  for  ten  miles  without 
being  inconvenienced,  but  he  cannot  run  up  two  flights  of  steep  stairs  with- 
out being  rendered  quite  breathless.  The  more  athletic  the  man,  the  better 
condition  of  training  he  is  in,  the  more  practice  he  has  had,  the  less  breath- 
less he  becomes  ;  but  the  most  perfect  athlete,  even  when  in  his  prime,  can 
soon  '  pump  himself  out '  if  he  tries. 

Dr.  Lagrange  offers  the  folloA^ing  explanation  of  the  phenomenon  : — 
Breathlessness  is  a  form  of  dyspnoea  due  to  an  excess  of  carbon  dioxide 
in  the  blood.     The  excess  of  this  gas  leads  to  an  increase  of  the  respiratory 
need.     The  condition  may  be  spoken  of  as  auto -intoxication  of  the  body  by 
one  of  its  own  products  of  dissimilation — carbon  dioxide. 


PHYSICAL  EDUCATION  5G1 

This  excess  of  carbonic  acid  is  produced  by  muscular  work.  It  is  a  con- 
spicuous product  of  such  work,  and  it  must  be  remembered  that  the 
muscles  form  at  least  half  the  weight  of  the  entire  body.  The  larger  the 
muscles  employed,  and  the  more  vigorous  their  action,  the  greater  is  the 
amount  of  the  gas  produced.  The  intensity  of  breathlessiiess  during  exercise 
is  in  direct  proportion  to  the  expenditure  of  force  demanded  in  a  given 
time.  Eunning  involves  rapid  contractions  of  the  great  mass  of  muscles 
forming  the  lower  extremities.  It  induces  breathlessness  quicker  than  does 
moderate  rowing,  where  the  muscular  expenditure  in  a  given  time  is  much 
less.  '  The  quantity  of  carbonic  acid,'  writes  Dr.  Lagrange,  '  produced 
by  a  group  of  muscles  in  a  given  time  is  in  proportion  to  the  amount  of  work 
they  do.  Further,  the  work  which  a  group  of  muscles  is  able  to  do  without 
fatigue  is  in  direct  ratio  to  the  power,  that  is,  to  the  number  and  size  of  the 
muscles  forming  this  group.  If,  then,  an  exercise  is  localised  in  a  very  small 
group  of  muscles,  fatigue  will  ensue  before  a  large  quantity  of  work  has  been 
done,  and  before  a  large  dose  of  carbonic  acid  has  been  poured  into  the  blood. 
The  eliminating  power  of  the  lungs  will  exceed  the  power  for  work  of  the 
active  muscles ;  muscular  fatigue  will  precede  breathlessness.  If,  on  the 
other  hand,  the  muscles  put  in  action  are  very  numerous  and  very  powerful, 
they  will  be  able  before  being  fatigued  to  perform  a  large  quantity  of  work, 
and  consequently  to  produce  a  very  large  dose  of  carbonic  acid.  Their  power 
for  work  will  exceed  the  eliminating  power  of  the  lungs.  Breathlessness 
will  this  time  precede  fatigue.' 

It  is  said  that  a  horse  '  trots  with  its  legs  and  gallops  with  its  lungs.' 
The  gallop  of  a  horse  may  be  slowed  down  until  the  animal  falls  behind 
another  horse  which  is  trotting.  Nevertheless,  however  slow  the  gallop  may 
be,  it  will  more  quickly '  pump  '  a  horse  than  an  equally  rapid  trot.  Swiftness 
of  movement  does  not  suffice  to  produce  breathlessness  unless  combined  with 
intensity  of  muscular  effort. 

In  breathlessness  it  is  not  inspiration  which  is  difficult,  but  expiration. 
In  running,  inspiration  is  free,  easy,  deep,  three  times  as  long  as  expiration. 
The  latter,  on  the  other  hand,  is  short,  insufficient,  and  painful. 

It  is  stated  that  in  man  there  is  discharged  m  a  given  time  by  respira- 
tion 

0*35  gramme  of  carbonic  acid  during  sleep. 
0"60         ,,  ,,         ,,         while  sitting. 

1"65         ,,  „         „         while  running. 

As  accessory  causes  of  breathlessness  are  certain  disturbances  in  the  cir- 
culation of  the  blood  and  some  engorgement  of  the  lungs  resulting  there- 
from. These  changes  are  discussed  by  Dr.  Lagrange  in  the  following 
words : — 

'  The  first  result  of  violent  exercise  is  the  quickening  of  the  blood  current 
and  a  consequent  active  congestion  of  the  lungs.  In  these  exercises  the  lungs 
are  very  quickly  engorged  with  blood,  and  there  is  great  need  for  their  dis- 
embarrassment by  increasing  the  activity  of  the  blood  current.  The  move- 
ment of  inspiration  increases  the  velocity  of  the  current  by  a  force  of 
aspiration  which  tends  to  empty  the  over-filled  capillaries.  This  aspiration 
lasts  as  long  as  the  enlargement  of  the  thorax  continues  ;  hence  this  move- 
ment is  an  assistance  to  the  breathless  man  ;  on  the  other  hand,  as  the  thorax 
is  diminishing  in  size  during  the  expiratory  movement,  the  blood  current 
becomes  slower  and  the  lungs  more  engorged.  Hence  the  discomfort  and  the 
irresistible  impulse  to  a  prompt  repetition  of  the  inspiratory  movement. 

'  We  may  say  that  the  lungs  of  the  breathless  man  are  placed  between  two 
different  needs.     On  the  one  hand,  they  have  to  drive  out  carbonic  acid  and 

VOL.    I.  0  0 


502  HYGIENE 

the  other  products  of  dissimilation,  and  for  this  a  long  expiration  would  be 
necessary  ;  but,  on  the  other  hand,  they  have  to  free  themselves  from  vascular 
engorgement,  and  therefore  expiration  is  cut  short  to  return  to  inspiration, 
which  helps  the  circulation  through  the  lungs.' 

Dr.  Lagrange  divides  breathlessness  into  three  stages,  and,  as  he  is  the 
only  writer  wlio  has  fully  dealt  with  this  subject,  the  matter  cannot  be  better 
discussed  than  in  his  own  words  :  — 

'  In  the  first  stcujc  the  respiratory  movements  are  increased  in  frequency 
and  in  extent.  The  production  of  carbonic  acid  is  increased,  but,  the  respi- 
ratory energy  being  greater,  there  is  an  equilibrium  between  the  needs  of 
the  organism,  which  demands  a  more  active  elimination  of  this  gas,  and  the 
working  of  the  lungs,  which  is  powerful  enough  to  satisfy  these  needs. 
During  a  time  which  varies  much  with  the  individual,  with  his  constitution, 
with  his  resistance  to  fatigue,  and,  above  all,  with  his  power  of  directing  his 
respiration,  gained  from  his  respiratory  education,  these  are  only  symptoms 
of  greater  vital  activity,  and  there  are  as  yet  no  signs  of  functional  disturb- 
ance, no  sensation  which  rises  to  the  degree  of  discomfort.  The  man  has  a 
general  sensation  of  warmth,  some  throbbing  of  the  temples,  and  has  an  ani- 
mated appearance,  flushed,  his  eyes  sparkling,  and  a  general  aspect  of  cheer- 
fulness, due  to  the  greater  activity  of  the  circulation  and  the  resulting  active 
congestions.  In  a  word,  it  is  the  stage  in  which  exercise  causes  a  greater 
intensity  of  life  without  reaching  the  degree  of  discomfoi-t  or  of  danger. 

'  Here  we  have  the  really  salutary  dose  of  exercise,  the  limits  within  which 
we  must  keep  in  order  that  work  may  cause  ns  no  inconvenience.  But 
nothing  varies  more  with  the  individual  than  the  duration  of  this  inoffensive 
period,  which  is,  in  a  sense,  the  preface  of  breathlessness.  In  some  persons 
it  is  as  long  as  an  hour,  in  others  the  stage  in  which  discomfort  begins  is 
reached  in  a  few  seconds. 

'  If  violent  exercise  be  prolonged,  the  equilibrium  is  soon  broken  between 
the  production  of  carbonic  acid,  which  becomes  more  and  more  abundant, 
and  the  eliminating  power  of  the  lungs,  which  is  insufficient  to  free  the 
organism  from  it.     Eespiratory  distress  occurs. 

'  In  the  second  period  the  effects  of  insufficient  respiration  begin  to  show 
themselves,  a  vague  discomfort  is  experienced,  which  is  most  accentuated  in 
the  pra3cordial  region,  but  which  is  rapidly  generalised  throughout  the  body, 
and  notably  affects  the  head.  In  the  chest  there  is  a  feeling  as  if  it  were 
oppressed  by  a  weight,  or  bound  down  by  a  girdle  of  insufficient  air.  In  the 
head  there  are  clouds  obscuring  sight,  sparks  before  the  eyes,  then  murmurs 
and  ringing  in  the  ears,  and  finally  a  certain  bluntness  of  sensation,  a  certain 
confusion  in  impressions  and  in  ideas.  All  these  disturbances  are  due  to  the 
action  upon  the  nerve-centres  of  an  excess  of  carbonic  acid.  They  indicate 
the  beginning  of  intoxication. 

'  In  the  face,  remarkable  changes  are  to  be  noticed,  which  are  the  conse- 
quences of  the  respiratory  distress,  and  of  the  efforts  made  to  draw  a  greater 
quantity  of  air  into  the  chest.  The  nostrils  are  dilated,  the  mouth  and 
eyes  widely  opened.  They  all  seem  to  be  widely  opened  to  favour  the 
entrance  of  the  air  which  the  lungs  so  greatly  need. 

'  The  colour  of  a  breathless  man  shows  very  striking  modifications.  At 
the  beginning  of  exercise  we  have  said  that  there  is  animation,  more  colour 
in  the  face,  due  to  active  congestion.  But  in  the  second  period  the  picture 
has  changed.  To  the  lively  red  colour  has  succeeded  a  pale  and  wan  tint. 
There  is  something  peculiar  about  this  pallor — it  is  not  uniform.  Certain 
parts  of  the"  face,  such  as  the  lips  and  the  cheeks,  have  a  violet  blackish 
appearance  ;  the  rest  of  the  face  is  white  and  colourless. 


PHYSICAL  EDUCATION  563 

'  From  the  two  colours,  one  darker  and  the  other  Hghter,  there  results 
a  grey,  leaden,  livid  appearance.  The  violet  tint  is  due  to  the  retention  of 
blood  in  the  capillaries,  which  are  losing  their  elasticity,  and  in  which  the 
■circulation  is  faihng.  This  blood,  overcharged  with  carbonic  acid,  has  lost 
its  bright  red  colour,  hence  in  the  lips  and  other  more  transparent  parts 
of  the  face  we  see  no  longer  the  ordinary  red  colour  ;  they  have  the  blackish 
colour  characteristic  of  venous  blood. 

'  As  for  the  pallor,  this  is  due  to  a  transient  anaemia,  to  the  emptying  of 
the  arterioles.  The  heart,  the  energy  of  which  diminishes  in  proportion  to 
the  increase  of  the  breathlessness,  does  not  send  forward  a  sufficient  quantity 
of  blood,  and  it  is  easy  to  understand  that  a  part  receiving  less  blood  is  less 
deeply  coloured  than  usual. 

*  The  leaden  hue  of  the  face  in  a  breathless  man  indicates  an  already 
profound  disturbance  of  the  system.  In  no  case  should  exercise  be  continued 
after  it  comes  on,  for  it  indicates  the  beginning  of  asphyxia. 

'  It  is  at  this  stage  of  breathlessness  that  we  observe  the  very  characteristic 
change  in  the  rhythm  of  respiration  which  has  been  already  described. 
The  ordinary  rhythm  is  lost,  and  the  two  periods  of  respiration  become 
unequal.  The  first  period  increases  and  the  second  diminishes  ;  inspiration 
becomes  three  times  as  long  as  expiration.  This  change  in  the  rhythm  of 
respiration  is  an  indication  of  blood  stasis  in  the  capillaries  of  the  lungs. 
As  soon  as  it  occurs  we  can  see  that  the  organism,  its  force  exhausted,  can 
no  longer  fight  to  good  purpose  against  the  poisonous  substance  which 
permeates  it.  The  congested  lungs  eliminate  less  carbonic  acid  than  is 
formed  by  the  muscles  at  work.     Intoxication  is  imminent. 

'  If  exercise  be  continued,  the  gravity  of  the  condition  rapidly  increases. 
We  may  call  the  asphyxial  stage  the  third  phase  of  breathlessness  into 
which  the  organism  passes  under  the  influence  of  forced  exercise. 

'  This  third  stage  is  as  follows.  To  the  respiratory  distress  succeeds  a 
sensation  of  anguish  generalised  throughout  the  organism.  The  head  feels 
as  if  bound  by  an  iron  band.  Vertigo  is  very  distressing.  All  sensations 
become  more  vague ;  the  brain  is  overcome  by  a  kind  of  drunkenness.  The 
subject  begins  to  become  unconscious  of  what  is  passing,  his  muscles  continue 
to  work  mechanically  for  a  time,  then  they  stop,  and  the  man  falls  in  a 
faint. 

'  At  this  time  respiration  is  of  a  different  type  to  that  of  the  last  stage ;  the 
two  periods  are  both  short,  jerky,  occasionally  interrupted ;  with  them  are 
mingled  swallowing  movements  and  hiccough.  The  heart-beat  is  feeble 
and  intermittent.  The  pulse  is  small,  irregular,  and  imperceptible.  When 
exercise  is  continued  to  these  extreme  limits  it  is  almost  always  stopped  by 
grave  syncope,  and  unless  prompt  help  be  given  the  syncope  may  be  fatal.' 

An  athletic  man  soon  develops  the  art  of  regulating  his  breathing  so  as 
to  reduce  the  degree  of  breathlessness  as  far  as  is  possible.  He  is  aware 
that  it  is  at  first  that  the  trouble  is  intense,  and  that  in  time  he  can  adjust 
the  difficulty  a  little.  The  runner  speaks  of  getting  '  his  second  wind.'  He 
has  passed  through  a  period  of  breathlessness  in  which  excitement,  sudden 
movement,  and  unnecessarily  extreme  muscular  contractions  possibly  have 
played  some  part ;  he  then  settles  down  to  his  work,  he  uses  his  forces  more 
economically  and  breathes  more  easily ;  and  it  is  common  to  hear  a  man  out 
of  condition  explain  the  loss  of  a  race  by  the  fact  that  he  never  got  his 
*  second  wind.' 

In  sprint  running  the  art  of  controlling  breathlessness  reaches  its  highest 
point,  and  to  some  extent  sprint  running  is  a  test  of  the  respiratory  capacity 
in  this  direction. 

0  o2 


5G1  HYGIENE 


2,  MuscuLAE  Fatigue 


If  a  man  in  sound  health  hold  out  his  arm  at  right  angles  to  his  body  he 
experiences,  in  a  time  which  varies  according  to  his  physical  condition,, 
so  much  inconvenience  in  the  muscles  involved  that  he  is  at  last  com- 
pelled to  drop  the  limb.  If  he  exercise  his  will  to  the  utmost  he  may 
prolong  the  period  of  extension,  but  a  time  soon  comes  when  by  no  possible 
effort  can  he  continue  to  hold  out  the  extremity. 

The  muscles  in  question  are  said  to  be  fatigued. 

The  fatigue  is  termed  relative  because,  if  a  proper  electric  current  b& 
applied  to  the  muscles  as  soon  as  the  limb  is  dropped  as  helpless,  the  muscles 
again  contract,  and  the  hand  is  once  more  lifted. 

If  the  muscles  of  an  animal  be  subjected  to  an  electric  current  they  con- 
tract ;  on  repeating  the  application  they  contract  again  and  again.  The 
contractions,  however,  become  feebler,  and  are  in  time  ultimately  abolished. 
The  parts  are  in  the  condition  of  relative  fatigue. 

If  now  a  stronger  current  be  employed,  the  muscles  again  contract,  and 
again  in  time  lose  their  power.  The  experiment  can  be  continued  with  a 
stronger  current  until  finally  the  muscles  camiot  be  made  to  contract  by  any 
cmTent  or  any  stimulus  of  any  kind. 

They  have  reached  the  state  of  absolute  fatigue. 

Local  fatigue  of  muscle  is  explained  by  the  following  conditions  : — 

1.  The  actual  power  or  function  of  the  muscle  is  exhausted.  This  con- 
dition has  been  termed  '  dynamic  exhaustion,'  and  is  parallel  to  the  exhaus- 
tion which  is  noticed  in  certain  reflex  acts  when  they  are  indefinitely  excited, 
and  to  the  exhaustion  of  the  retina  to  certain  rays  when  one  colour  is  con- 
templated for  too  long  a  time. 

The  functional  power  of  a  muscle  is  placed  within  definite  limits,  and  in 
fatigue  that  limit  is  reached.  This  exhaustion  is  modified  by  the  strength 
of  the  muscle,  by  its  local  condition,  by  the  practice  it  has  been  subjected  to, 
and  by  the  nerve  condition  of  the  individual. 

2.  In  fatigue,  nerve  exhaustion  is  largely  concerned.  This  especially 
applies  to  complicated  acts,  the  repetition  of  which  involves  a  special  and 
definite  effort  of  the  will. 

The  comparative  absence  of  exhaustion  in  the  incessant  movements  in 
chorea  is  explained  by  the  circumstance  that  in  these  movements  a  voluntary 
nerve  mechanism  is  not  concerned.  Dr.  Lagrange  lays  down  the  axiom  that, 
'  the  muscular  work  being  equal,  the  sensation  of  fatigue  is  the  more  intense 
the  more  active  the  intervention  of  the  cerebral  faculties  demanded  by  the 
exercise.' 

3.  Some  local  effect  may  be  exercised  upon  the  muscle  by  the  products  of 
combustion  or  dissimilation  which  are  developed  within  its  tissues,  and  which, 
not  being  got  rid  of  in  time  enough,  accumulate  in  excess. 

*  If,'  WTites  Dr.  Lagrange,  '  w^e  submit  the  muscles  of  a  frog  to  the  action 
of  a  powerful  electric  stimulus,  and  prolong  this  action  until  fatigue  is  com- 
plete, that  is,  till  the  limbs  of  the  animal  remain  motionless  under  the  most 
powerful  stimulation,  we  shall  have  in  the  fatigued  muscles  the  elements 
necessary  for  a  most  curious  experiment.  Their  substance  rubbed  in  a  mortar 
and  made  into  a  fine  soup  contains  a  principle  capable  of  producing  in 
healthy  muscle  at  rest  the  fatigue  which  had  exhausted  the  first  muscles. 
If  we  inject  into  a  second  frog  this  extract  of  fatigued  muscles,  we  bring 
about  in  this  animal  all  the  phenomena  of  fatigue,  and  its  limbs  will  fail  to 
respond  to  electric  stimuli.' 


PHYSICAL  EDUCATION  565 

The  possible  character  of  this  local  effect  is  thus  dealt  with  by  Landois  in 
his  -well-known  '  Text-book  of  Physiology '  (translated  by  Stirling).  The 
«ause  of  local  muscular  fatigue  '  is  probably  partly  due  to  the  accumulation 
of  decomposition  products — "fatigue  stuffs" — in  the  muscular  tissue,  these 
products  being  formed  within  the  muscle  itself  during  its  activity.  They  are 
phosphoric  acid,  either  free  or  in  the  form  of  acid  phosphates,  acid  potassium 
phosphate,  glycerin-phosphoric  acid  (?),  and  carbonic  acid.  If  these  substances 
be  removed  from  a  muscle  by  passing  through  its  blood-vessels  an  indiffer- 
ence solution  of  common  salt  .  .  .  the  muscle  again  becomes  capable  of 
energising.' 

Dr.  Lagrange  gives  a  more  detailed  account  of  these  tissue  changes,  and 
in  adding  his  account  it  is  necessary  to  say  that  his  statements  are  not 
entirely  in  accord  with  the  teaching  of  most  physiologists. 

'  Muscles  which  have  worked  to  excess  have  undergone  a  change  in  their 
chemical  composition.  Alkaline  in  a  state  of  repose,  they  have  become  acid ; 
they  contain  lactic  acid,  which  was  not  present  before  work ;  they  contain 
less  oxygen  and  more  carbonic  acid  than  when  at  rest.  Numerous  nitrogen- 
ous materials  resulting  from  the  combustion  of  muscular  tissues  are  consider- 
.ably  increased.  These  substances,  of  which  the  last  stage  of  combustion  is 
nrea,  form  a  series  of  bodies  only  differing  in  containing  more  or  less  oxygen, 
and  being  consequently  at  a  different  degree  of  oxidation  or  combustion.  All 
.authors  enumerate  amongst  them  kreatin,  hypoxanthin,  inosite,  &c.,  and 
finally  the  best  known  one,  and  the  most  interesting  because  of  the  part  it 
plays  in  the  production  of  gout,  uric  acid.' 

4.  It  is  possible  also  that  some  actual  lesion,  such  as  that  attending  the 
compression  of  nerves,  may  occur  in  a  fatigued  muscle  and  may  serve  to 
partly  explain  the  tenderness  of  the  overused  structure  and  to  estabhsh  a 
condition  akin  to  that  produced  by  the  violent  and  irregular  contractions  of 
•cramp. 

3.  Muscular  Stiffness 

Another  feature  associated  with  local  fatigue,  with  the  overuse  of  muscle, 
is  stiffness.  This  is  a  common  but  not  a  necessary  accompaniment  of  the 
over-work. 

A  rowing  man  who  is  entirely  out  of  condition,  and  who  has  taken  no 
exercise  for  months,  is  asked  to  fill  up  a  place  in  a  racing  four  for  a  short 
'  practice.'  He  finds  the  exertion  a  terrible  strain  ;  he  soon  becomes  breathless, 
his  limbs  ache,  his  head  throbs,  every  limb  seems  out  of  condition,  and  he  is 
soon  exhausted.  He  does  his  best  through  the  short  spin,  but  next  day  he 
aches  all  over.  He  is  stiff.  He  feels  as  if  he  had  been  beaten.  He  cannot 
move  without  some  pain,  nor  can  he  grasp  any  part  of  his  body  without  dis- 
covering some  tenderness. 

In  a  day  or  so  the  unpleasant  condition  passes  off.  This  very  man  may 
have  rowed  many  races  without  experiencing  a  trace  of  stiffness.  He  may 
have  gone  through  three  times  the  amount  of  exertion  without  any  but 
momentary  inconvenience.  The  difference  has  been  simply  this.  At  one 
time  he  was  in  practice  and  in  condition,  at  the  other  time  he  was  both 
out  of  practice  and  out  of  condition. 

The  intensity  of  the  stiffness  is  not  always  proportionate  to  the  imme- 
diate fatigue,  nor  is  the  extent  of  the  exercise  a  measure  of  the  stiffness  which 
may  result. 

Stiffness  depends  rather  upon  the  condition  of  the  individual  than  upon 
the  character  or  amount  of  the  muscular  work  done.  Muscles  may  be 
fatigued  without  afterwards  becoming  stiff. 


5GG  HYGIENE 

The  local  symptoms  of  stiffness  probably  depend  upon  an  exaggeration  of 
those  conditions  in  the  muscles  which  are  supposed  to  underlie  local  fatigue,, 
and  notably  to  the  retention  in  the  tissues  of  the  products  of  combustion. 

These  local  changes  have  already  been  described. 

4.  Geneeal  Fatigue 

The  general  disturbances  Avhich  may  accompany  muscular  exhaustion, 
and  which  are  present  in  some  degree  in  such  fatigue  as  is  attended  by 
stiffness  are  of'very  varying  character. 

The  indi\'idual  may  be  left  simply  exhausted,  '  tired  out,'  listless,  and  to 
some  extent  prostrate. 

In  more  advanced  degrees  he  complains  of  heaviness  in  the  head,  of  utter 
feebleness,  of  inability  to  take  food,  and  of  painful  weariness  and  restlessness 
followed  by  want  of  sleep. 

In  other  and  still  more  pronounced  cases  he  may  exhibit  febrile  pheno- 
mena and  present  the  condition  described  as  the  '  fever  of  over-exertion.' 
This  fever  may  be  attended  with  such  malaise  and  with  such  nerve  dis- 
turbances as  to  be  mistaken  for  the  early  period  of  an  infective  fever. 

This  coiidition  has  been  elaborately  considered  by  Dr.  Knott,  of  Dublin,  in 
his  excellent  monograph  on  '  The  Fever  of  Over-exertion '  (Dublin,  1888). 
He  takes  the  case  of  a  greatly  overworked  farm  labourer.  The  symptoms  may 
or  may  not  commence  with  a  rigor.  The  patient's  temperature  runs  up  rapidly,, 
even  to  103°  F.  or  101°  F.  within  a  few  hours,  and  this  change  is  accompanied 
by  the  general  symptoms  of  malaise,  congested  face,  thirst,  loss  of  appetite. 
Sec.  He  soinetimes  takes  a  day  or  two  of  rest,  when,  feeling  a  little  better, 
he  makes  a  desperate  effort  to  go  back  to  work,  although  still  suffering  from 
the  same  symptoms  in  a  slighter  degree.  His  efforts  are  now  necessarily 
less  vigorous,  but  he  does  enough  to  feed  the  slow  fire  of  febrile  combustion 
which  has  been  already  kindled  in  his  muscles. 

The  temperature  maintains  a  standard  of  about  101°  or  so ;  the  pulse  is 
permanently  quickened  ;  thirst,  constipation,  loss  of  appetite,  and  loaded  urine 
contmue. 

In  such  cases,  when  the  pernicious  attempts  at  manual  exertion  are  con- 
tinued for  a  number  of  days,  the  unhappy  individual  afterwards  fails  to 
recover.  Gradual  wasting  goes  on  ;  the  pulse  maintains  its  frequency  and 
becomes  weaker,  the  strength  by  degrees  fails,  the  patient  is  obliged  to  take 
to  bed,  the  fever  tends,  after  some  months,  to  assume  a  hectic  type. 
Increasing  emaciation  is  marked,  and  the  patient  not  very  rarely  falls  a 
victim  to  some  intercurrent  disease. 

Dr.  Knott  ascribes  the  phenomena  to  the  throwing  into  the  circulation  of 
a  greatly  disproportionate  quantity  of  the  products  of  muscular  waste.  These, 
he  maintains,  lead  to  an  overthrow  of  the  governing  powers  of  the  thermo- 
toxic  nerve  centre,  or,  in  other  words,  are  the  substantial  cause  of  the  fever. 
He  considers  that  urea  and  uric  acid  represent  the  most  important  of  these 
products. 

Dr.  Lagrange  supports  the  same  view,  and  contends  that  the  marked  con- 
stitutional disturbances  which  may  follow  upon  severe  muscular  exercise  are 
all  due  to  the  accumulation  in  the  circulation  of  a  large  excess  of  the 
chemical  products  of  muscular  waste,  to  a  species  of  self-infection  by  the 
excess  of  combustion  products  developed  in  the  muscles.  He  also  considers 
that  these  products  are  mainly  represented  by  urea  and  allied  compounds. 

It  is  noteworthy  that  a  degree  of  fatigue  leading  to  muscular  stiffness, 
but  not  necessarily  to  the  constitutional  symptoms  named,  will  be  attended. 


PHYSICAL  EDUCATION  5G7 

by  a  deposit  of  urates  in  the  urine.     This  may  be  quite  independent  of  any 
fever. 

Those  who  pursue  athletic  exercises  are  well  aware  of  the  association 
of  a  deposit  in  the  urine  with  the  appearance  of  stiffness.  In  a  man  out 
of  condition  the  tissue  waste  induced  during  unwonted  exercise  is  very  con- 
siderable. The  tissues  afford  abundant  reserve  material  for  the  necessary 
combustions.  The  nutritive  condition  of  his  muscles  is  comparatively  low. 
In  an  athlete  in  training,  on  the  other  hand,  the  material  available  for  com- 
bustion is  not  in  excess.  The  tissues  have  long  been  rid  of  all  superfluous 
matter.  The  nutritive  state  of  the  muscles  is  in  the  best  possible  condition, 
and  the  circumstances  which  favour  the  development  of  a  great  deposit  of 
urates  is  not  forthcoming. 

EFFECTS   OF   EXCESSIVE   OR   UNSUITABLE   EXEECISE 

It  is  unnecessary  to  deal  in  a  separate  section  with  the  ill-effects  of  an 
absence  of  physical  exercise  upon  the  body.  The  matter  has  been  considered 
in  such  of  the  foregoing  paragraphs  as  are  concerned  in  the  general  effect 
of  muscular  exercises. 

In  estimating  the  actual  value  of  the  work  done  in  any  physical  pursuit,  or 
in  attempting  to  express  what  is  meant  by  '  excessive '  or  '  unsuitable '  in 
relation  with  muscular  labour,  I  have  been  unable  to  make  any  use  of  the 
physiological  method  of  measuring  work  by  '  foot-tons.'  This  mode  of  mea- 
surement is  no  doubt  of  value  to  the  physiologist,  but  to  those  concerned 
in  physical  education  it  is  practically  useless.  Many  of  the  results  do  not 
accord  with  what  would  be  inferred  from  practical  experience,  nor  can  they 
be  put  to  any  practical  use.  The  amount  of  muscular  expenditure  incurred 
in  rowing  one  mile  at  racing  speed  is  said  to  be  represented  by  18*56 
foot-tons.  But  walking  a  mile  at  an  ordinary  pace  causes  an  expenditure  of 
17*67  foot-tons,  from  which  it  must  be  inferred  that  there  is  very  little  differ- 
ence between  these  two  forms  of  exercise,  so  far  as  the  use  of  the  muscles  is 
concerned.  Those  who  are  interested  in  athletic  matters  would  not  be  able  to 
recognise  the  correctness  nor  the  value  of  these  estimates,  especially  when  they 
are  compared  with  one  another.  Even  when  every  allowance  is  made  for  the 
quickness  of  the  stroke  and  the  breathlessness  induced  by  rowing  at  a  racing 
pace,  yet  still  it  would  be  urged  that  the  actual  output  of  muscular  force 
would  be  represented  by  a  different  figure  when  such  exercise  is  compared 
with  the  walking  of  one  mile. 

Bowing  six  miles  at  racing  speed  would,  upon  the  same  estimate,  be  re- 
presented by  111*36  foot-tons,  while  walking  the  same  distance  would  be  ex- 
pressed by  106*02  foot-tons — a  result  which  makes  the  comparison  still  more 
marked. 

So  far  as  the  present  purpose  of  this  paper  is  concerned,  the  terms  '  ex- 
cessive exercise '  and '  unsuitable  exercise  '  must  be  considered  relatively,  and 
with  reference  rather  to  the  individual  than  to  the  actual  physiological 
amount  of  muscular  work  expended. 

What  may  be  excessive  or  unsuitable  exercise  to  one  man  may  be  moderate 
and  quite  excellent  exercise  to  another. 

In  considering  the  phenomena  of  fatigue  and  the  effects  of  any  given 
exertion  the  estimate  must  be  based  upon  the  condition  of  the  individual 
rather  than  upon  the  actual  character  of  the  work  carried  out.  In  this  matter 
the  age  and  bodily  development  of  the  man,  the  state  of  his  general  health, 
and  the  scope  and  extent  of  his  muscular  education  play  prominent  and 
essential  parts. 


5G3  HYGIENE 

The  effects  whicli  may  follow  upon  excessive  or  unsuitable  exercise,  or 
upon  exercise  which,  from  the  point  of  view  of  him  who  practises  it,  may  be 
termed  violent  on  the  one  hand  and  rash  on  the  other,  are  very  varied. 

We  have  seen  in  the  sections  on  breathlessness  and  on  general  fatigue 
what  results  may  follow  after  severe  exertion,  so  far  especially  as  the  respi- 
ratory functions  and  the  general  state  of  the  body  arc  concerned. 

A  sprint  runner  may  fall  senseless  upon  the  path,  succumbing  to  the 
results  of  his  breathlessness. 

A  boy  may  remain  completely  '  knocked  up  '  for  several  days  after  a  paper- 
chase,  and  may  be  really  ill  and  exhibit  the  febrile  phenomena  which  have 
been  already  described. 

There  is  no  doubt  that  in  not  a  few  instances  the  pursuit  of  violent  and 
extreme  exercise  has  led  to  results  which  have  had  a  permanent  effect  upon 
the  health  of  the  individual.  In  some  cases  an  actual  organic  lesion  has 
been  produced  ;  in  others  the  body  has  been  placed  in  a  condition  favourable 
for  the  development  of  disease  ;  in  a  third  series  of  instances  there  super- 
venes merely  a  feebler  state  of  health. 

The  children  of  tubercular  parents  have  acquired  a  spinal  caries,  or  a 
diseased  joint,  as  a  result  of  injuries  received  through  improper  gymnastic 
exercises. 

Children  wit\)  a  weak  muscular  system  have  acquired  a  lateral  curvature 
of  the  spine  through  the  pursuit  of  unsuitable  exercises,  which,  so  far  as  their 
spinal  muscles  are  concerned,  have  been  excessive  and  unequal. 

It  may  be  true,  as  is  often  asserted,  that  phthisis  has  appeared  in  those 
who  are  phthisically  incHned,  as  a  result  of  the  strain  and  the  exposure 
incident  to  severe  exercises  of  endurance  in  the  open  air. 

Many  serious  troubles  may  certainly  be  ascribed  to  acts  of  indiscretion 
and  to  exposure  to  cold  and  wet  under  trying  circumstances  during  the 
pursuit  of  physical  exercise  ;  but  such  ills  can  scarcely  be  laid  at  the  door  of 
muscular  training.  The  attack  of  acute  rheumatism,  which  may  have  followed 
a  long  boating  tour  in  the  late  autumn,  may  more  justly  be  ascribed  to  camp- 
ing out  in  the  wet  than  to  the  effect  of  mere  rowing. 

Quite  apart  from  any  obvious  lesion  or  disease,  not  a  few  individuals 
appear  to  suffer  permanently  in  health  as  the  result  of  some  specific  excess 
in  the  matter  of  exercise.  A  lad  may  '  knock  up'  after  winning  a  three-mile 
race,  and  never  be  fit  for  much  in  the  matter  of  athletics  after  that.  A  man 
of  about  middle  age  may,  with  probable  reason,  date  a  distinct  and  persistent 
decline  in  health  to  some  one  holiday  in  Switzerland,  when  he  did  more 
than  his  age  and  his  condition  justified. 

Many  inferences  of  this  character  may  be  unsound,  but  a  few  appear  to 
be  undoubted. 

On  the  whole,  however,  it  must  be  allowed  that  the  injury  which  may 
follow,  and  no  doubt  has  now  and  then  followed,  upon  severe  physical 
exertion  represents  but  a  small  fraction  when  compared  with  the  undoubted 
benefits  which  accrue  from  moderate  and  reasonable  exercise. 

Dr.  John  E.  Morgan,  of  Manchester,  in  a  work  entitled  '  University  Oars  : 
a  Critical  Inquiry  into  the  Health  of  the  IMen  who  Rowed  in  the  Oxford  and 
Cambridge  Boatrace,  from  1829  to  18G9,'  has  dealt  with  the  effect  of 
violent  exercise,  as  illustrated  by  racing  in  boats,  upon  the  general 
health. 

His  evidence  shows  that  such  exercise  is,  in  the  great  majority  of  instances, 
no  other  than  beneficial ;  that  it  is  not  a  cause  of  disease  or  of  premature 
death ;  and  that,  out  of  the  large  number  of  individuals  dealt  with,  in  only 
the  insignificant  proportion  of  G  per  cent,  could  any  permanent  ill  effect 


PHYSICAL  EDUCATION  5G0 

be  claimed  to  have  followed  the  pursuits  of  earlier  years.  In  most  of 
these  cases  even  the  evidence  that  rowing  was  to  blame  was  indefinite  or 
doubtful. 

Mr.  Walter  Eye,  the  well-known  authority  on  cross-country  running, 
writes  thus  :  '  We  can  speak  from  an  experience  now  covering  nearly  twenty 
years,  and  can  positively  say  that  we  know  of  no  man  of  the  hundreds  with 
whom  we  have  been  acquainted  who  has  been  injured  by  distance  running, 
and  the  rate  of  mortality  among  running  men  is  singularly  small.' 

Similar  evidence  has  been  given  by  others  with  regard  to  forms  of  athletic 
exercise  which  may  be  considered  to  be  violent. 

Certain  specific  effects  which  may  follow  upon  excessive  or  unsuitable 
exercise  will  now  be  considered. 

The  Heart  and  Blood-vessels 

The  heart  has  been  ruptured  during  very  violent  exertion,  as  in  attempting 
to  lift  or  support  an  immense  weight.  This  has  happened  to  men  of  great 
muscular  strength,  but  more  often  to  the  feeble,  the  ill-conditioned,  or  the  aged. 

Excessive  exercise  may  lead  also  to  hypertrophy  of  the  heart,  to  dilatation 
of  its  cavities,  and  to  valvular  disease.  The  cases  of  hypertrophy  appear  to  be 
most  usual  in  the  athletic,  and  in  those  whose  employments  involve  constant 
severe  labour — e.g.  blacksmiths,  miners,  &c.  In  the  matter  of  dilatation  of 
the  heart.  Dr.  W-  Osier  writes  (Pepper's  '  Medicine,'  vol.  iii.  p.  631) :  '  Over- 
training and  heart-strain  are  closely  connected  with  the  question  of  excessive 
dilatation  during  severe  muscular  effort.  Both  mean  the  same  thing  in  many 
cases.  A  man,  perhaps  not  in  very  good  condition,  calls  upon  his  heart  for 
much  extra  work  during  a  race  or  the  ascent  of  a  very  steep  mountain,  and  is 
seized  with  cardiac  pain  and  a  feeling  of  distension  in  the  epigastrium,  and 
the  rapid  breathing  continues  an  unusual  time,  but  the  symptoms  pass  off 
after  a  night's  quiet.  An  attempt  to  repeat  the  exercise  is  followed  by 
another  attack,  and,  indeed,  an  attack  of  cardiac  dyspnoea  may  come  on 
while  he  is  at  rest.  For  months  such  a  man  may  be  unfitted  for  severe 
exertion  or  may  be  permanently  incapacitated.  He  has  overstrained  his 
heart  and  has  become  broken- winded.' 

HaBmorrhages  of  various  kinds  have  resulted  from,  or  have  been  ascribed 
to,  violent  exertion,  and  have  been  met  with  in  almost  all  parts  of  the 
body.  Cases  of  cerebral  and  of  spinal  apoplexy  have  occurred  during  extreme 
exertion,  and  Lagrange  mentions  an  instance  in  which  the  spinal  veins 
underwent  rupture  and  led  to  paraplegia. 

Aneuetsm 

The  part  played  by  exercise  in  the  production  of  aneurysm  is  definite,  but 
at  the  same  time  not  necessarily  predominating.  In  addition  to  violent 
movement  come  the  factors  of  actual  injury  to  the  vessel,  constitutional 
diseases,  especially  syphilis,  and  the  conditions  which  lead  to  chronic  arteritis. 
The  author  once  saw  a  popliteal  aneurysm  in  an  acrobat  of  twenty-eight,  who 
was  in  perfect  health,  and  who  considered  it  had  been  developed  by  the  practice 
of  hanging  by  the  knees  from  one  trapeze  while  he  caught  his  companion,  who 
was  swinging  from  another.  In  this  case  great  and  well-localised  x^ressure 
was  exerted  upon  the  ham.  The  form  of  exercise  which  appears  to  be  most 
effective  in  the  production  of  aneurysm  is  violent  intermittent  exercise,  or 
sudden  exercise  when  out  of  condition,  or  such  actions  as  involve  extreme 
movements  of  certain  articulations. 

Aneurysm  is  much  more  common  in  men  than  in  women,  and  in  the 


570  HYGIENE 

labouring  than  in  the  favoured  classes.  It  is  noteworthy  that  in  the  etiology 
of  aneurysm  age  plays  a  conspicuous  part.  Aneurysm  is  not  most  common 
at  the  age  when  violent  physical  exercises  are  most  usually  indulged  in,  but 
it  is  most  frequent  in  individuals  who  have  reached  or  have  passed  middle 
life.  The  occurrence  of  aneurysm  under  these  circumstances  affords  another 
argument  against  the  folly  of  violent  and  extreme  exertion  in  men  who  are 
over  thirty,  especially  when  they  are  out  of  condition. 

Varicose  Veins 

The  frequently  repeated  statement  that  varicose  veins  in  the  lower  limbs 
are  produced  and  maintained  by  exercise  is  based  upon  very  questionable 
foundations.  It  is  said  upon  equally  questionable  grounds  that  those  who 
indulge  in  running,  bicycling,  riding,  or  exercises  involving  long  standing 
are  in  great  risk  of  developing  varicose  veins.  It  is  quite  true  that  dilated 
veins  are  met  with  among  athletes,  runners,  and  bicyclists  ;  but  it  has  not 
been  shown  that  the  condition  is  more  common  among  them  than  it  is  with 
other  individuals,  and,  on  the  other  hand,  it  is  easy  to  produce  any  number 
of  professional  runners,  athletes,  gymnasts,  and  others  who  are  constantly 
practising  the  very  exercises  which  are  said  to  produce  varicose  veins,  and  yet 
have  not  an  enlarged  vein  in  either  of  their  lower  hmbs. 

It  is  remarkable,  moreover,  that  varicose  veins  are  so  much  more  common 
among  women  than  among  men,  and  that  they  are  very  often  met  with  in 
women  who  take  httle  or  no  exercise.  There  is,  in  fact,  evidence  to  show 
that  exercise  has  little  if  anything  to  do  with  the  production  of  the  disease ; 
that  the  trouble  is  due  to  certain  congenital  defects  in  the  vessels  them- 
selves, and  that  when  such  defect  does  exist  muscular  exertion  may  tend  to 
increase  the  abnormal  condition.  This  view  is  very  strongly  insisted  upon 
by  Mr.  Bennett  in  his  elaborate  monograph  upon  '  Varicose  Veins  '  (London, 
1889).  He  shows  that  there  is  a  distinct  hereditary  history  in  more  than 
60  per  cent,  of  the  cases.  His  cases  prove  that  the  trouble  occurs  in  the 
active  and  the  sedentary,  in  the  weak  and  the  strong,  in  the  short  and  the 
tall.  In  females  pregnancy  and  constipation  play  a  conspicuous  part  in  the 
etiology.  Bennett  is  unable  to  connect  the  occupation  of  the  patient  in  any 
definite  degree  with  the  actual  production  of  the  disease.  While  exercise 
probably  has  nothing  to  do  with  originating  varices,  it  certainly  tends  to 
increase  the  trouble  when  it  exists.  Eunning,  walking,  jumping,  cycling, 
and  forms  of  exercise  and  recreation  involving  long  standing  are  noteworthy 
in  their  ill  effects  upon  varicose  veins.  Indulgence  in  these  exercises  would 
be  unwise  for  those  who  are  the  actual  subjects  of  the  disease,  but  the 
fear  of  enlarged  veins  should  never  be  an  obstacle  in  the  way  of  a  free 
pursuit  of  the  sports  mentioned,  nor  can  the  possibility  of  varicose  veins  be 
legitimately  urged  as  an  argument  against  these  sports. 

The  Lungs 

Haemoptysis  and  emphysema  are  stated  to  have  been  produced  by  violent 
exertion,  and  many  chronic  lung  troubles  have  no  doubt  followed  upon  ex- 
posure and  neglect  during  and  after  such  exertion.  Dr.  Parkes  states  that 
congestion  of  the  lungs  may  follow  upon  excessive  or  badly  arranged 
exercise. 

Bones  and  Muscles 

Bones  have  been  fractured  by  pure  muscular  violence,  notably,  the 
clavicle  and  humerus,  but  in  the  majority  of  such  instances  the  bone  has 
proved  to  have  been  diseased  at  the  seat  of  fracture. 


PHYSICAL  EDUCATION  571 

Violent  exercise  may  lead  to  all  kinds  of  lesions  of  the  muscles.  Muscles 
may  be  ruptured  in  whole  or  in  part,  tendons  may  be  rent  across  or  torn 
away  from  the  bone,  or  may  be  displaced  from  the  grooves  in  which  they  lie. 
In  many  instances  the  subject  of  these  lesions  is  out  of  condition,  or  is  in 
feeble  health  or  aged,  or  is  suffering  from  definite  disease. 

The  Hon.  E.  Lyttleton  well  says  ('  Health  Exhibition  Manuals,'  vol.  x. 
p.  121):  '  To  an  athlete  the  first  premonition  of  coming  old  age  is  to  sprain 
himself  somewhere.' 

Muscles  which  are  over-exercised  for  a  considerable  time  waste  and 
become  soft.  The  legs  of  professional  runners  are  occasionally  quite  atro- 
phied from  over-use  of  the  muscles  of  the  parts. 

The  abuse  of  certain  movements  and  the  excessive  repetition  of  the  same 
may  lead  to  some  permanent  contraction  of  the  muscles  concerned.  Thus  in 
professional  gymnasts  who  use  the  flexors  of  the  arm  to  excess  the  elbow  may 
be  found  to  be  a  little  flexed  and  full  extension  of  the  joint  to  be  impossible. 
Sailors  on  sailing  vessels  who  are  constantly  holding  or  hauling  ropes  not 
infrequently  develop  a  condition  of  the  hand  which  prevents  full  extension 
of  the  fingers. 

The  finer  muscles  when  unreasonably  employed  may  become  the  subject 
of  such  nervous  changes  as  are  illustrated  by  writer's  cramp  and  other  forms 
of  spasm  incident  to  certain  employments. 

Joints  may  be  injured  by  violent  exertion.  Synovitis  may  follow  upon 
over-use  of  an  articulation,  and  one  very  common  accident  among  the  athletic 
is  a  displaced  semilunar  cartilage  in  the  knee-joint. 

Certain  deformities  of  the  body  may  follow  restricted  and  often  repeated 
exercises  and  the  excessive  employment  of  certain  muscles.  Gymnasts  who 
have  developed  to  an  extreme  degree  the  muscles  of  the  upper  limbs  and  upper 
half  of  the  trunk  have  a  rounded  back  in  addition  to  their  unwieldy  shoulders. 

Fencing  tends  to  produce  a  lateral  curvature  of  the  spine  with  (in  right- 
handed  fencers)  the  concavity  of  the  curve  to  the  right.  The  author  has 
observed  a  permanent  degree  of  lordosis  in  an  acrobat  who  produced  extra- 
ordinary results  by  his  power  of  bending  the  body  backwards  at  the  lumbar 
region. 

Hernia 

The  influence  of  muscular  exertion  in  the  etiology  of  hernia  is  so  fully 
dealt  with  in  the  ordinary  text-books  of  Surgery  that  it  need  not  be  considered 
at  length  in  this  place. 

In  cases  of  congenital  hernia  and  in  such  other  forms  as  depend  upon 
defects  in  the  vaginal  process  of  the  peritoneum,  and  in  those  instances  of 
hernia  generally  which  are  met  with  in  young  children,  the  rupture  is  made 
manifest  by  some  expulsive  effort  as  a  rule,  and  not  by  any  movements  that 
can  be  considered  as  constituting  exercise. 

Acquired  hernise  are  beyond  doubt  produced  by  forces  tending  to  cause  the 
intestines  to  protrude. 

Violent  effort  is  a  recognised  factor  in  the  production  of  these  ruptures. 
It  is  very  rarely  indeed,  however,  the  sole  factor.  Certain  anatomical  con- 
ditions are  present  which  render  a  hernia  possible  in  one  man  and  almost 
impossible  in  another. 

It  is  noteworthy  that  the  main  safeguard  against  hernia  is  a  perfect  and 
vigorous  muscular  development.  The  greater  number  of  examples  of  acquired 
hernia  are  met  with,  not  only  in  men  of  imperfect  muscular  development,  but 
in  individuals  who  are  out  of  condition.     Such  hernife  are  commoner  in 


572  HYGIENE 

those  who  return  to  hihorious  work  after  an  illness  or  when  in  feebler 
health,  in  men  who  undertake  heavy  work  without  any  preliminary  training, 
in  persons  who  by  reason  of  their  age  or  their  habits  are  losing  muscular  tone, 
are  becoming  coarse,  soft,  andtlabby,  are  developing  fat  within  the  abdomen, 
and  wbo  exhibit  the  phenomena  of  relaxed  tissue.  Gymnasts  and  acrobats, 
in  spite  of  the  immense  muscular  efforts  they  put  forth,  are  seldom  the  sub- 
jects of  hernia.  If  they  become  ruptured  the  hernia  will  appear  late  in  their 
career,  at  a  time  when  they  are  falling  off  and  losing  tone,  or  at  any  period 
when  they  are  out  of  condition  and  out  of  training. 

Carefully  selected,  systematic,  and  well-graduated  exercise  is  the  best 
protection  against  hernia,  and  the  objections  against  athletics  founded 
upon  the  production  of  hernia  are  unjust  and  unsound.  An  acquired 
umbiUcal  hernia  is  unknown  in  muscular  men  ^vith  firm  abdominal  walls. 
It  is  common  in  those  who  have  large,  flabby,  and  pendulous  bellies  and 
who  take  no  exercise  at  all.  So  far  as  acquired  hernia  is  concerned,  it  would 
be  more  accurate  to  state  that  rupture  is  due  to  want  of  exercise  rather  than 
to  excessive  indulgence  in  the  same. 


TEAINING 

With  '  training  '  in  the  sense  of  preparing  the  body  for  athletic  competi- 
tions and  great  feats  of  endurance  the  present  article  has  no  concern.  The 
subject  may  be  considered  only  in  so  far  as  it  throws  hght  upon  the  mode  of 
living  which  may  be  observed  by  those  who  are  anxious  to  get  themselves 
into  condition  and  to  take  a  considerable  amount  of  moderate  exercise. 

Upon  this  subject  a  number  of  books,  pamphlets,  and  articles  have  been 
written,  and,  it  must  be  confessed,  a  great  deal  of  nonsense  promulgated. 

Strange  elements  of  superstition  and  gross  ignorance  have  entered  into  the 
older  methods  of  training,  and  there  are  still  professional  athletes  who  keep 
the  details  of  their  training  secret  or  who  ascribe  their  success  to  some 
article  of  food  or  some  particular  rite  or  observance. 

The  old  system  of  training  was  quite  remarkable.  The  unfortunate  man 
had  his  weight  reduced  by  profuse  sweating,  especially  by  walking  and 
running  in  thick  and  heavy  clothes.  He  was  purged  every  day,  he  was 
almost  starved  in  the  matter  of  water,  and  took  sparingly  of  old  ale,  spirits, 
and  port.  He  lived  mainly  upon  half-cooked  beefsteaks  and  bread,  and  was 
encouraged  to  gorge  himself  upon  this  monotonous  diet. 

Matters  are  now  entirely  changed,  so  far,  at  least,  as  amateur  athletes  are 
concerned,  and  without  entering  into  detail  as  to  the  exact  methods  practised 
by  one  modern  system  or  another,  the  general  features  of  a  reasonable  mode 
of  training  may  be  briefly  discussed. 

In  the  first  place,  time  must  be  considered.  '  A  man  of  twenty-five  and 
upwards,'  writes  Mr.  Woodgate,  '  who  has  been  lying  by  for  months,  or  it  may 
be  for  a  year  or  two,  can  do  with  three  months  of  training.  The  first 
half  should  be  less  severe  than  the  last.  He  can  get  into  "  hunting  "  condi- 
tion in  the  first  six  weeks  and  progress  to  "  racing"  condition  in  the  suc- 
ceeding six.  University  crews  train  from  five  to  six  weeks.  College  crews 
cannot  give  much  more  than  three  weeks  to  train  for  the  summer  bumping 
races.' 

During  training  a  man's  life  must  be  as  regular  as  a  clock  :  his  meals 
must  be  taken  to  the  minute,  his  exercises  must  be  systematised  and  so  ad- 
justed as  to  be  progressive  and  well-timed.  He  should  retire  to  bed  early 
and  rise  early,  should  sleep  in  a  well-ventilated  room,  should  bathe  night 


•    .  PHYSICAL  EDUCATION  573 

and  morning,  should  be  particular  as  to  the  kind  of  clothing  worn,  and 
take  every  precaution  to  avoid  cold.  In  all  things  he  should  be  moderate 
and  methodical.  His  meals  are  best  represented  by  a  substantial  breakfast, 
a  light  lunch,  a  still  lighter  tea,  and  a  substantial  dinner  in  the  evening 
when  his  day's  work  is  over.  He  should  take  plenty  of  sleep.  He  should 
rest  after  each  meal.  Smoking  should  be  absolutely  forbidden,  and  no  form 
of  alcohol  should  be  allowed.  There  is  overwhelming  evidence  to  support 
the  practice  of  training  upon  water.  In  the  matter  of  diet  a  man  should  be 
moderate,  should  not  gorge  himself,  and  should,  within  certain  limits,  con- 
sult his  own  taste  in  the  selection  of  food. 

He  will  do  best  with  the  most  easily  digested  foods,  and  may  take 
beef,  mutton,  chicken,  fish,  and  game,  while  he  should  avoid  pork  and  veal 
and  lobster  and  other  well-accredited  producers  of  dyspepsia.  He  should 
under  no  circumstances  be  debarred  from  eating  fat  and  butter.  A  man  in 
training  needs  a  good  supply  of  carbon  in  his  food. 

It  is  well  to  avoid  much  sloppy  food,  such  as  soups  and  broths,  to  be  very 
moderate  in  the  consumption  of  starchy  foods  and  of  sugar,  to  avoid  coarse 
vegetables  and  large  quantities  of  potatoes.  Some  green  vegetables  and  some 
fruit  should  be  taken  every  day.  It  is  needless  to  say  that  he  should  avoid 
pastry  and  sweets  and  the  confused  and  uncertain  forms  of  food  known  as 
entrees.  Cheese  may  well  be  omitted  from  his  dietary  and  salad  take  a  con- 
stant place.     Meat  will  be  eaten  at  breakfast,  lunch,  and  dinner. 

In  the  matter  of  liquids,  he  should  not  drink  for  the  sake  of  drinking. 
He  should  take  as  much  only  as  is  needed  to  quench  his  thirst,  and  he 
should  not  consider  the  time  of  his  drinking.  The  custom  of  allowing  men 
to  drink  only  a  certain  quantity  of  water  at  certain  fixed  times  of  the  day 
is  obviously  silly.  A  man  should  drink  when  he  is  thirsty,  and  should  not 
be  compelled  to  suffer  with  a  parched  mouth  simply  because  the  drinking 
hour  has  not  come.  Men  differ  immensely  m  the  quantity  of  fluid  they 
need.  The  matter  cannot  be  settled  by  rule.  It  may  be  taken  as  certain 
that  the  least  quantity  is  consumed  when  taken  in  small  amounts,  and  often, 
and  not  when  the  individual  has  been  tortured  with  thirst  and  swallows  a 
quart  or  more  vrhen  his  time  for  drinking  comes. 

Under  a  reasonable  and  liberal  system  of  training  no  man  should  break 
down  or  become,  as  the  expression  goes,  '  stale.' 

The  old  system  of  training  was  rather  a  test  of  strength  than  a  means  of 
developing  it,  and  those  who  train  in  modern  times  should  make  themselves 
familiar  with  the  follies  of  those  who  trained  in  days  gone  by. 


SPECIFIC   EXEECISES 

Walking 

is  the  most  usual,  the  most  simple,  the  most  easy,  and  one  of  the  most  valu- 
able modes  of  taking  exercise.  It  is  suited  for  individuals  of  all  ages  and  of 
all  states  of  development.  It  is  the  main  exercise  of  the  quite  young  child, 
a  prominent  feature  in  the  training  of  the  athlete,  and  usually  the  only  form 
of  exercise  indulged  in  by  the  aged. 

It  is  a  mode  of  exercise  which  requires  neither  apparatus  nor  special 
locality,  and  there  can  be  few  so  engaged  in  the  pursuit  of  living  as  to  find 
a  legitimate  excuse  for  not  indulging  in  this  simple  means  of  kee]Ding  the 
body  in  health. 

While  walking  exercises  mainly  the  muscles  of  the  legs,  it  brings  into 


574  HYGIENE 

play  also  the  muscles  of  the  loin  and  of  the  back  and  abdomen.  Not  only 
has  the  individual  to  move,  he  has  also  to  keep  erect.  The  circulation  and 
respiratory  movements  are  increased,  and  the  general  beneficial  effects  of 
exercise  are  brought  about. 

The  actual  mechanics  of  walking  and  the  precise  nature  and  extent  of 
the  movements  involved  are  admirably  illustrated  by  the  photographs  pub- 
lished by  Mr.  Eadweard  Muybridge,  of  Philadelphia.  Certain  of  these  are 
reproduced  with  a  very  lucid  explanation  in  Keating's  *  Cyclopaedia  of  the 
Diseases  of  Children  '  (vol.  iv.  1891). 

Walking  is  distinct  from  marching,  in  which  a  less  easy  attitude  of  the 
body  is  maintained.  Other  things  being  equal,  slow  walking  is  more  tiring 
than  walking  at  a  moderate  pace. 

It  is  important  that  the  style  of  walking  be  cultivated,  that  the'  spine 
be  kept  straight,  the  head  erect,  and  the  shoulders  well  back.  An  easy  and 
perfectly  graceful  mode  of  walking  is  not  common  among  civilised  people. 
The  countryman  rolls  along  walking  from  his  hips,  the  over-dressed  lady 
steps  stiffly  and  gingerly  like  an  automaton,  the  untrained  lad  slouches  in  a 
manner  well  termed  slovenly. 

A  purposeless  walk,  such  as  is  the  common  exercise  and  often  the  only 
exercise  in  ladies'  schools,  where  the  pupils  walk  in  procession,  side  by  side, 
over  a  stated  distance,  is  somewhat  depressing  and  does  not  develop  the 
exercise  to  its  fullest.  Walking  with  an  object  represents  the  best  and  most 
pleasant  form  of  this  element  in  physical  training.  Shooting  involves,  not 
only  the  delights  and  excitement  of  sport,  and  the  use  of  the  hands  and 
arms,  but  also  a  long  walk  over  often  irregular  and  difficult  ground.  The 
admirable  game  of  golf,  which  is  said  to  date  from  the  time  of  Edward  III., 
represents  one  of  the  very  best  forms  of  walking  Avith  an  object.  This  game 
has  a  fascination  both  for  the  young  and  the  old,  and  is  one  of  the  most 
perfect  and  in  every  way  the  most  admirable  form  of  exercise  for  men  who 
are  past  middle  life  or  have  reached  old  age. 

Walking  races  are  contests  more  or  less  of  endurance,  and  test  rather 
the  staying  powers  than  the  skill  or  the  muscular  strength  of  the  competitor. 
]\f any  professional  walkers  walk  vilely.  In  walking  for  a  race  '  it  is  abso- 
lutely necessary,'  writes  a  great  authority  (Mr.  Shearman),  'to  have  the 
muscles  so  hard  all  over  the  body  that  "  knocking  off"  for  any  space  of  time 
becomes  fatal  to  all  chances  of  success.' 

In  walking  competitions  the  mile  has  been  covered  in  6  min.  23  sec, 
three  miles  in  20  min.  21^  sec,  twenty  miles  in  less  than  3  hours,  and  fifty 
miles  in  less  than  8  hours. 

EUNNING 

is  the  exercise  for  children  and  young  people.  It  employs  the  muscles  of 
nearly  the  whole  of  the  body  and,  by  increasmg  the  rate  and  depth  of  the 
respirations,  is  an  admirable  element  in  developing  the  chest.  Children 
appear  to  be  the  subjects  of  an  irresistible  impulse  to  run,  an  impulse  that 
should  never  be  checked. 

Running  has  been  described  as  a  succession  of  leaps.  It  undoubtedly  has 
a  most  beneficial  effect  upoii  the  circulation  of  the  viscera,  strengthens  the 
heart,  when  indulged  in  in  moderation  brings  out  the  individual's  powers 
of  endurance  as  well  as  his  strength  and  his  capacity  for  rapid  movement. 

Muybridge's  photographs  show  the  mechanical  details  of  the  act  of 
running  very  clearly.  A  reproduction  of  two  of  these  photographs  in 
Keating's  '  Cyclopaedia  '  Hoc.  cit.)  may  be  advantageously  consulted. 

Eunning,  to  any  extent,  as  an  exercise  is  not  advisable  after  the  age 


PHYSICAL  EDUCATION  675 

of  thirty,  nor  in  those  who  have  not  kept  themselves  in  practice  and 
in  sound  condition.  In  the  aged  it  may  be  ranked  often  as  actually 
dangerous.  The  best  ages  for  running  are  between  eighteen  and  twenty-five, 
and  upon  few  forms  of  athletic  exercise  does  age  tell  more  certainly  and 
a<ccurately  than  in  this. 

So  far  as  athletic  excellence  is  concerned,  it  may  be  said  that  a  runner  is 
born,  not  made.  There  are  many  wlio  would  never  attain  a  first  position 
as  runners  in  spite  of  unlimited  practice.  Sprint  running  or  sprinting  is  the 
term  applied  to  running  a  short  distance  at  top  speed  without  a  break. 
Three  hundred  yards  is  considered  to  represent  the  limit  of  sprinting  dis- 
tance. '  In  sprinting,'  writes  Mr.  Shearman, '  the  front  muscles  of  the  thigh 
which  bring  the  leg  forward  are  the  most  important  factors  for  speed,  as  it 
is  on  the  rapid  repetition  of  the  stride  that  the  main  result  depends  ;  in  the 
running  of  longer  distances  the  back  muscles  of  the  thigh,  which  effect  the 
propulsion,  bear  the  chief  strain.  Both  sets  of  muscles  are,  of  course,  used 
in  every  race,  but  the  longer  the  distance  the  less  important  the  front 
muscles  become.'  The  sprinter,  however,  runs  rather  with  his  lungs  and 
heart  than  with  his  legs.  Breathlessness  is  the  difficulty  with  which  he  has 
to  contend.  Thus  it  happens  that  the  sprinter  may  be  tall  or  short,  may  be 
a  feather  weight  or  scale  at  13  stone,  may  have  limbs  like  a  deer  or  calves 
which  would  cause  the  envy  of  a  footman. 

Long-distance  running  is  a  matter,  not  only  of  strength,  but  also  of 
endurance  and  lung  power.  Some  of  the  best  long-distance  runners  have 
been  short  men,  very  strong,  light  of  weight,  and  with  large  and  deep  chests. 

Hare  and  hounds  and  the  paper-chase  form  most  exciting  and  admirable 
forms  of  running.  The  sport,  however,  is  only  open  to  those  who  are  young, 
who  are  in  perfect  condition,  and  who  have  increased  the  distances  they 
have  run  from  time  to  time  by  gradual  steps. 

For  children  a  hoop  forms  one  of  the  most  popular  means  of  giving  a 
purpose  to  running  and  of  infusing  interest  into  what  in  the  abstract  is  a 
somewhat  monotonous  form  of  exercise. 

On  the  racing  track  100  yards  has  been  covered  in  10  sec,  and  300  yards 
in  30  sec.  A  mile  has  been  completed  in  4  min.  12|  sec,  three  miles  in 
14  min.  29  sec,  twenty  miles  in  a  few  minutes  short  of  two  hours,  and  fifty 
miles  in  a  little  short  of  six  hours. 

Jumping, 

like  running,  has  certain  very  definite  age  limits.  Jumping  in  competi- 
tions is  limited  to  individuals  under  thirty  or  more  usually  under  twenty- 
five.  Twenty  may  be  taken  as  the  best  age.  In  jumping,  the  muscles 
■of  the  lower  limb  are  of  course  mainly  employed,  but  in  addition  to 
these  it  will  be  noticed  that  nearly  every  muscle  in  the  body  is  in  action 
as  the  leap  is  taken.  The  details  of  the  movement  are  well  shown  in 
Muybridge's  photographs  {see  Keating's  '  Cyclopedia,'  vol.  iv.  photo  v.). 

A  jumper  of  any  excellence  is,  like  a  runner,  born,  not  made.  Celebrated 
jumpers,  especially  long  jumpers,  have  been  of  almost  any  size  and  weight. 
W.  B.  Page,  who  cleared  a  height  of  6  ft.  3;^  in.,  was  only  5  ft.  6  in.  in  height. 

Jumping  as  an  element  of  physical  education  has  some  especial  points 
of  value.  It  encourages  very  vigorous,  instantaneous,  and  well  co-ordinated 
muscular  contractions,  and  cultivates  that  form  of  muscle  intelHgence  which 
is  called  spring. 

I  am  of  opinion  that  jumping  is  not  quite  the  exercise  for  women  or  for 
young  girls  who  have  passed  the  period  of  puberty.  Certain  uterine  troubles 
have  with  some  show  of  reason  been  ascribed  to  an  indulgence  in  this  exer- 


576  HYCrlEXE 

cise.  For  flabby  people  and  young  subjects  who  are  disposed  to  be  stout, 
and  for  any  who  are  not  in  very  sound  condition,  the  exercise  is  not  with- 
out risk.  It  may  well  be  left  to  lads  and  to  youths  in  the  prime  of  athletic 
life. 

In  the  high  jump  6  ft.  3^  in.  have  been  cleared,  and  in  the  long  jump  the 
remarkable  distance  of  23  ft.  2  in. 

Allied  to  jumping  must  be  considered  the  exercise  of  skipping.  A  more 
admirable  and  more  perfect  form  of  exercise,  considering  its  simplicity,  could 
not  be  practised.  It  employs  the  muscles,  not  only  of  the  legs  and  loins,  but 
also  of  the  back,  abdomen,  and  neck,  and  even  the  muscles  of  the  arms ; 
it  especially  tends  to  strengthen  the  ankles  and  knees  and  the  arches  of 
the  foot ;  it  is  admirable  for  children  with  weak  backs  ;  it  increases  the 
respiratory  movements  to  a  marked  extent ;  and  if  practised  upon  grass  and 
in  the  open  air  it  is  one  of  the  most  perfect  forms  of  exercise  for  young  girls 
that  could  be  devised. 

Those  who  consider  skipping  too  simple  and  too  trivial  to  form  a  serious 
element  in  a  physical  education  may  be  surprised  to  know  that  many  athletes 
and  gymnasts,  and  notably,  it  must  be  owned,  prize  fighters,  take  a  very  large 
part  of  the  exercise  prescribed  during  training  by  means  of  the  skipping-rope. 

It  would  be  well  if  those  parents  who  consider  that  nothing  in  the  way  of 
physical  training  can  be  done  without  a  gymnasium  or  a  drill-sergeant  would 
invest  in  a  hoop  and  a  skipping-rope  and  take  note  of  the  effect  produced  by 
these  simple  means. 

A  skipping  competition  upon  a  lawn  or  in  a  field  is,  when  kept  within 
limits,  one  of  the  most  perfect  forms  of  recreation  a  girl  can  indulge  in.  It 
should  be  carried  out  in  slippers  or  light  shoes,  and  if  it  were  a  little  more 
popular  the  feeble  ankles  and  flat  feet  which  are  so  common  among  girls 
and  women  would  certainly  be  less  often  met  with. 

Skating 

is  another  admirable  exercise,  especially  valuable  from  the  fact  that  it  can 
be  practised  at  a  time  when  few  forms  of  outdoor  recreation  are  possible, 
and  when  girls  and  women  are  apt  to  sit  at  home  and  huddle  over  a  fire  or 
weary  themselves  by  dancing,  until  the  small  hours  of  the  morning,  in  a 
heated  ballroom. 

Skating  is  a  form  of  modified  walking,  but  it  calls  into  play  a  greater 
variety  of  muscles.  The  balance  has  to  be  maintained  and  the  muscles  of 
the  abdomen,  back,  and  loins  have  much  to  do.  It  is  exhilarating,  it  is 
admirably  adapted  for  persons  of  almost  all  ages,  and  is  as  well  suited  for 
females  as  for  males  ;  it  comes  at  a  time  when  the  want  of  exercise  in  the 
open  air  is  probably  telling  upon  the  health  and  spirits  ;  it  tends  to  give  an 
easy  and  graceful  carriage  to  the  body  ;  it  strengthens  the  ankles  and  is  a 
fine  antidote  for  the  flimsier  form  of  nervousness.  No  mode  of  progression 
upon  the  feet  is  more  delightful,  easy,  or  invigorating.  In  a  country 
house  when  every  form  of  indoor  amusement  has  been  exhausted,  when  the 
roads  are  too  dirty  for  walking  and  the  ground  too  heavy  for  pleasant  riding, 
a  hard  black  frost  comes  as  a  boon,  and  the  manner  in  which  the  youv.g 
and  the  old,  the  strong  and  the  frail,  turn  out  and  hurry  to  the  ice  gives  the 
impression  that  the  instinct  for  exercise  in  human  beings  is  as  strong  as 
the  impulse  which  leads  the  duckling  to  the  water. 

In  racing,  the  following  distances  have  been  covered  in  the  times  named  : 
100  yards  in  10  sec,  one  mile  in  3  min.  2G  sec. ;  three  miles  in  10  min.  33  sec, 
twenty  miles  in  1  hr.  14  min. ;  fifty  miles  in  4hrs.  13  min. 


PHYSICAL  EDUCATION  577 


ElDINO 


is  a  mode  of  taking  exercise  and  fresh  air  which  is  not  open  to  all,  and  is 
within  certain  narrow  limits  denied  to  the  inhabitants  of  cities. 

The  muscles  exercised  in  riding  are  those  mainly  of  the  adductor  segment 
of  the  thigh  and  of  the  back.  The  movement  undoubtedly  improves  the 
visceral  circulation  and  affords  a  remedy  for  hepatic  congestion  and  constipa- 
tion ;  it  promotes  a  deeper  respiration  and  a  more  active  pulse ;  it  com- 
bines in  a  remarkable  manner  both  active  and  passive  movement  and  is 
a  specific  for  the  dyspepsia  and  other  ills  which  attend  a  sedentary  life ; 
it  provides  a  means  of  strengthening  the  spine,  and  it  should  be  remembered 
that  a  good  '  seat '  implies  rather  the  power  of  keeping  the  trunk  well  balanced 
than  the  power  of  gripping  the  saddle  with  strong  adductor  muscles. 

It  is  a  pursuit  that  can  be  indulged  in  from  childhood  to  old  age,  and  it 
is  one  of  the  most  popular  forms  of  exercise  among  Englishwomen. 

Children  should  learn  young  and  should  be  well  taught.  The  exercise 
is  not  good  for  girls  with  commencing  lateral  curvature,  nor  should  it  be 
taken  up  by  children  who  have  '  outgrown  their  strength,'  and  are  tall,  weedy, 
and  of  feeble  muscular  development,  until  the  muscles  have  been  strengthened 
by  other  methods.  Overgrown  girls  who  indulge  in  no  other  exercise  but 
riding  are  apt  to  become  round-shouldered  and  round-backed  and  to  acquire 
a  very  ungraceful  seat.  Lateral  curvature  of  the  spine  is  certainly  often 
induced  and  fostered  by  riding. 

In  any  instance  a  young  girl  should  be  taught  to  ride  upon  either  side  of 
the  saddle,  and  this  precaution  should  be  especially  observed  in  the  case  of 
those  who  are  supposed  to  have  weak  backs.  After  a  very  long  ride  a  man 
feels  most  tired  in  the  lower  part  of  his  spine,  and  is  very  disposed  to  loll  in 
the  saddle.  In  a  young  girl  the  most  important  muscular  strain  comes  upon 
the  back,  and  is  concerned  in  keeping  the  body  erect. 

It  is  not  uncommon  to  see  girls,  who  have  been  badly  taught,  riding  with 
the  body  much  bent  to  one  side  or  with  the  spine  '  all  in  a  heap  '  and  in  the 
attitude  of  cyphosis.  Eiding  is  not  the  best  kind  of  exercise  for  the  round- 
shouldered  and  for  such  girls  as  have  unequally  developed  chests. 

Horse  exercise,  so  far  as  ladies  are  concerned,  is  a  little  hampered  by  the 
fashion  which  demands  that  a  riding  habit  shall  fit  like  a  glove  and  that,  as 
a  consequence,  the  waist  should  be  compressed  so  as  to  reach  fashionable 
proportions.  The  long  skirt  of  the  riding  habit  adds  not  a  httle  to  the  danger 
of  horse  exercise  for  women. 

Eiding  forms  an  admirable  exercise  for  men  who  have  reached  or 
have  passed  middle  life,  and  the  saddle  is  very  often  the  last  thing  that  an 
old  sporting  man  relinquishes  as  infirmity  creeps  on. 

Professional  horsemen  (grooms,  postilions,  jockeys,  &c.)  are  apt  to  develop 
a  certain  deformity  of  the  lower  limbs  and  back.  The  legs  tend  to  become 
concave  or  bowed,  and  seem  often  to  have  been  stunted  in  growth.  The 
back — especially  in  jockeys — tends  to  become  arched  and  rounded  and  the 
shoulders  high.  An  old  ostler  and  an  old  jockey  have  often  a  quite  charac- 
teristic figure  and  attitude. 

The  deformity,  such  as  it  is,  is  evidently  the  result  of  style  in  riding,  as 
it  is  not  observed  in  artillerymen  and  other  cavalry  soldiers 

Swimming 

should  be  taught  as  a  matter  of  routine  to  every  child,  and  it  is  a  disgrace 
to  this  country  that  this  very  simple  accompUshment  is  so  rare.     Swimming 

VOL.    I.  p  p 


578  HYGIENE 

is  easily  learnt  at  any  age,  and  when  once  mastered  is  never  forgotten.  It 
is  acquired  nearly  as  quickly  by  girls  as  by  boys,  and  the  first  lessons  may 
be  given  between  the  ages  of  eight  and  ten. 

Swimming  calls  into  use  a  new  set  of  muscles  or  rather  a  new  combina- 
tion of  muscles.  In  the  early  struggles  of  the  learner  an  immense  amount 
of  force  is  expended  in  carrying  out  the  unaccustomed  movements.  As  pro- 
ficiency is  attained  the  movement  becomes  easier  and  easier,  ruitil  it  is  as 
simple  as  walking,  and  the  hmits  of  the  swimmer's  powers  are  restrained 
rather  by  the  temperature  of  the  water  than  by  his  muscles. 

Few  modes  of  exercise  are  more  enjoyable,  especially  when  practised  in  a 
broad  river  or  the  open  sea. 

The  muscles  of  both  the  upper  and  lower  extremities  are  concerned,  and 
to  a  lesser  degree  the  muscles  of  the  back  and  abdomen.  The  scapular 
muscles,  the  deltoid,  the  pectorals,  and,  above  all,  the  latissimus  dorsi  are 
especially  employed  in  swimming.  The  arms  tire  before  the  legs,  and  the 
sense  of  exhaustion  is  always  experienced  most  about  the  shoulder. 

Work  m  a  gymnasium  is  an  excellent  means  of  developing  the  swimming 
muscles,  and,  so  far  as  long  distances  are  concerned,  the  chief  factors  are 
strong  arms  and  a  good  chest. 

Swimming  increases  the  respiratory  movements  and  straightens  the  back. 
The  movements  of  the  limbs  are  very  free,  and  afi'ord  a  striking  contrast  to 
most  of  the  other  forms  of  exercise  which  concern  the  lower  hmbs. 

Swimming  should  be  well  taught.  Considering  the  facilities  afforded  in 
this  country  for  acquiring  the  art,  it  is  astounding  that  among  those  who  do 
swim  a  fine  and  easy  style  of  swimming  is  so  rare. 

Probably  some  70  per  cent,  of  those  who  can  smm  can  just  '  swim  a 
little,'  and  can  do  not  more  than  keep  themselves  afloat  by  extravagant  move- 
ments for  fifty  or  100  yards. 

I  do  not  think  that  the  practising  of  the  swimming  movements  on  land  is 
of  much  value,  although  it  forms  a  great  feature  in  the  gymnastic  course  in 
France. 

The  most  remarkable  swimming  feat  was  that  of  Matthew  Webb,  who 
swam  from  Dover  to  Calais  in  21  hrs.  45  min.  In  a  race  100  yards  has  been 
covered  in  1  min.  6  sec. 

Fencing 

In  the  Badminton  Library  volume  on  Fencing  the  history  of  this  art  is 
detailed,  together  with  the  circumstances  and  manner  of  its  development,  and 
to  the  account  is  appended  a  quite  remarkable  bibliography  of  the  subject. 

Fencing  as  it  is  at  present  pi'actised  is  an  extremely  scientific,  precise, 
and  highly  elaborated  art.  It  is  no  mere  slashing  with  a  protected  foil. 
Every  move  has  been  systematised ;  every  method  of  attack  and  defence  has 
its  individual  name.  The  movements  are  as  complex,  and  yet  as  well  defined, 
as  the  movements  of  the  men  upon  a  chessboard.  No  mode  of  exercise  has 
reached  a  more  elaborate  degree  of  finish.  Fencing  is  pre-eminently  an 
exercise  of  skill.  Considerable  employment  is  given  to  all  the  muscles  of  the 
body,  to  the  lower  hmbs,  and  to  the  back,  but  principally,  it  is  needless  to  say, 
to  the  right  or  sword  arm.  The  beginner  will  after  his  first  few  lessons  ache 
from  head  to  foot.  He  will  believe  that  he  has  been  fencing  with  every 
muscle  he  possessed,  a  belief  which  will  be  well  founded.  As,  however,  he 
becomes  more  proficient  he  will  feel  that  the  strain  falls  to  a  great  extent  upon 
the  right  upper  extremity. 

Fencing  is  as  much  an  exercise  of  the  brain  as  of  the  muscles.     He  who 


PHYSICAL  EDUCATION  579 

lias  acquired  some  proficiency  in  the  art  will  find  that  he  becomes  tired  in 
his  brain  and  cord  rather  than  in  his  limbs.  The  bout  induces  rather  a 
nerve  than  a  muscle  fatigue. 

Fencing  develops  certain  faculties  in  an  admirable  manner.  It  requires 
quickness  of  eye,  extreme  readiness  of  action,  accurate  muscular  sense,  great 
precision  and  fineness  of  movement,  and  perfect  powers  of  ready  co-ordination. 
It  involves  the  practice  of  a  quick  decision,  a  rapid  judgment,  and  a  good 
memory.  A  fool  could  never  become  a  good  fencer,  even  if  he  were  endowed 
with  the  most  excellent  physical  qualifications. 

Fencing  has  become  more  popular  of  late  years,  and  is  an  excellent 
•exercise  for  busy  men.  It  is  to  be  regretted  that  the  practice  often  takes 
place  in  somewhat  ill-ventilated  rooms.  Fencing  for  elder  children  and 
for  ladies  forms,  as  it  is  usually  practised,  but  a  somewhat  imperfect  develop- 
ment of  the  proper  art.  It  is  not  the  exercise  which  would  be  recommended 
'to  excitable,  nervous,  or  overworked  children.  It  is  better  adapted  for  those 
who  appear  to  be  apathetic  and  dull.  A  dull  boy  will  find  a  fencing  lesson 
an  infinitely  greater  '  fag '  than  whole  pages  of  irregular  verbs. 

It  should  never  form  for  children,  or,  indeed,  for  adults,  an  exclusive  or  even 
predominant  form  of  exercise  on  account  of  the  imequal  muscular  develop- 
ment it  encourages.  It  is  well  suited  to  encourage  in  lads  and  in  elder  girls 
a  good  carriage,  free  movements,  a  lissom  and  graceful  attitude  of  the  body, 
great  agility,  and  both  muscular  and  mental  quickness.  If  it  is  possible 
to  make  an  individual  '  sharp,'  fencing  may  be  considered  as  capable  of 
doing  it. 

The  exercise  must  be  recommended  with  great  care.  It  would  be  in- 
jurious to  those  who  have  a  disposition  to  lateral  curvature,  and  to  any  who 
are  the  subjects  of  unequal  muscular  development. 

In  the  physical  education  of  the  young  it  can  occupy  but  a  small  space. 
It  is  a  perfect  exercise  for  adults,  especially  for  men  who  lead  sedentary 
and  monotonous  lives.  Dr.  Lagrange  asserts  that '  everyone  who  has  fenced 
much  shows,  in  a  more  or  less  pronounced  degree,  a  lateral  curvature  of  the 
■spine.'  In  right-handed  fencers  the  concavity  of  the  curvature  is  to  the 
right,  in  the  left-handed  to  the  left.  The  shoulder  of  the  arm  which  holds 
iihe  foil  is  lowered.  Dr.  Lagrange  founds  his  conclusions  upon  the  exami- 
nation of  twenty  experienced  fencers.  The  tendencies  to  deformity  are  very 
unequally  marked.  In  some  the  deviations  are  quite  trivial,  in  others  they 
are  pronounced.  This  evidence  is  of  considerable  importance  in  forming  an 
estimate  of  the  value  of  fencing  as  a  muscular  exercise,  especially  to  those 
who  are  under  twenty  or  twenty-five  years  of  age. 

Boxing, 

if  carried  out  under  proper  conditions,  and  especially  if  practised  in  the  open 
air,  is  an  admirable  exercise  for  lads  and  young  men.  Unfortunately  the 
surroundings  of  a  boxing  saloon  are  not  always  the  best  adapted  for  the 
education  of  youth,  and  the  so-called  '  professors  '  of  the  art  are  not  usually 
the  best  associates  for  plastic-minded  lads. 

The  exercise  itself,  however,  is  admirable.  It  brings  into  play  prac- 
tically all  the  muscles  of  the  body.  A  vigorous  blow  is  struck  as  much 
from  the  leg  and  trunk  as  from  the  arm.  It  has  been  well  said  that  a  good 
and  powerful  blow  starts  from  the  foot.  Mitchell,  in  the  monograph  upon 
boxing  in  the  Badminton  Library  series,  says  :  '  It  may  seem  paradoxical 
and  provoke  a  smile  to  say  that  the  first  necessity  for  using  the  fists  pro- 
perly is  to  understand  the  use  of  the  feet.'     The  boxer  needs  to  be  agile, 

pp2 


580  HYGIENE 

to  be  able  to  use  his  legs,  to  be  quick  with  the  movements  of  his  head  and 
his  trunk.  Boxing,  moreover,  gives  excellent  use  to  the  left  arm,  which 
is  apt  to  be  neglected  in  many  other  forms  of  exercise.  It  calls  for  rapidity 
of  movement,  ready  decision,  good  judgment,  and  a  control  of  the  temper.  It 
promotes  the  ch-culation,  and  in  a  vigorous  round  the  boxer  is  very  soon 
rendered  breathless. 

The  atmosphere  in  a  boxing  saloon  is  not  always  so  well  supplied  with 
fresh  air  as  it  might  be. 

Boating 

It  may  perhaps  be  said,  without  fear  of  contradiction,  that  boating  pre- 
sents one  of  the  most  complete,  uniform,  and  delectable  forms  of  exercise. 
It  is  an  exercise  which  is  especially  associated  with  the  English,  and  it  is  in 
England  that  the  sport  is  the  most  highly  elaborated  and  the  most  widely 
practised.  Boats  of  one  form  or  another  appear  among  the  environment  of 
such  primitive  peoples  as  have  lived  by  the  sea  or  about  the  banks  of  navi- 
gable rivers  ;  but  the  development  of  boating  as  a  fine  art,  the  perfecting  of 
this  picturesque  and  enjoyable  mode  of  locomotion,  rests  with  the  sturdy 
and  watcr-lovuig  sons  of  England.  Surrounded  on  all  sides  by  the  sea,, 
and  living  in  a  land  permeated  by  many  rivers,  it  is  not  unnatural  that  an 
Enghsh  lad  should  take  to  the  water  like  a  duck,  and  should  feel  that 
enthusiastic  love  for  the  sea  which  appears  to  be  almost  an  hereditary  taste, 
and  which  is  possibly  not  a  little  influenced  by  the  great  naval  records  of 
the  country. 

For  every  professional  rowing  man  in  our  midst  there  will  be  hundreds 
of  amateurs  who  are  by  no  means  a  discredit  to  the  sport.  At  all  public 
schools  situated  within  reach  of  water,  rowhig  is  a  prominent  feature  of  school 
life.  At  the  two  great  Universities  of  Oxford  and  Cambridge  boating  occu- 
pies a  position  which  the  less  robust  section  of  the  public  are  apt  to  consider 
a  little  too  conspicuous.  The  whole  length  of  the  Thames  from  Oxford  to 
London  durmg  the  few  months  of  the  English  summer  is  alive  with  boats, 
and  is  animated  by  rowers  of  all  classes  and  all  ages.  Among  this  busy,  sun- 
browned,  and  white-flannelled  community  may  be  seen  old  men  and  maidens^ 
as  well  as  young  men  and  children. 

The  sheer  delight  given  by  the  mere  circumstances  of  boating  requires 
little  comment.  It  needs  merely  the  conception  of  a  stretch  of  fair  water,  the 
early  morning  of  a  day  in  the  English  summer,  a  light  outrigger,  and  a  pair  of 
sculls  to  every  point  of  which  the  sculler  has  fitted  his  muscles.  There  is  the 
crisp  grasp  of  the  water,  the  swish  of  the  blades,  the  shooting  of  the  tiny 
craft  across  the  polished  river,  the  whistling  of  the  wind  about  the  rower's 
head,  and  the  rippling  of  the  water  as  the  prow  runs  through  the  magic 
lights  and  shadows  which  are  thrown  from  the  bank. 

Boating  offers,  moreover,  one  of  the  most  charming  forms  of  touring.  A 
man  may  spend  many  summer  holidays  in  a  boat  or  in  a  canoe  before  he  has 
exhausted  the  beauties  of  the  rivers  of  Great  Britain. 

Across  the  Channel  the  system  of  canals  on  the  Continent  offers  an  un- 
paralleled opportunity  for  a  journey  such  as  has  been  described — as  no  other 
pen  could  have  described  it — by  R.  Louis  Stevenson  in  his  '  Inland  Voyage.' 

It  is  greatly  to  the  credit  of  England  that  her  waterways  are  more 
densely  peopled  with  boating  folk  than  are  the  waters  of  any  other  country  of 
hke  population. 

With  regard  to  boats,  it  is  only  necessary  to  say  that  for  racing  the  keel- 
less  boat  is  employed.  Its  bottom  is  round  and  smooth.  Such  a  boat  is 
extremely  unsteady  and  requires  all  the  skill  of  a  novice  to  '  sit  it.'     The 


PHYSICAL  EDUCATION  581 

iDGginner  may  find  no  difficulty  in  propelling  such  a  boat,  but  he  will  expe- 
Tience  considerable  difficulty  in  keeping  in  it.  The  sculler  in  a  racing  boat 
lias,  like  the  bicyclist,  first  to  balance  himself  and  then  to  move. 

The  outrigger  was  introduced  in  1842  by  Clasper. 

This  very  simple  improvement  enables  a  greatly  increased  length  and 
greater  advantage  in  leverage  to  be  given  to  the  oars,  while  at  the  same 
time  it  allows  the  dimensions  of  the  racing  craft,  and  especially  of  the  beam, 
to  be  much  reduced.  The  ordinary  length  of  an  inrigged  pair-oared  pleasure 
boat  or  gig  is  22  ft.  and  the  beam  3  ft.  9  in.  The  length  of  a  racing  sculling 
boat  will  be  about  31  ft.  and  the  beam  about  11  inches. 

Another  noteworthy  improvement — the  invention  of  an  American — was  the 
sliding  seat,  which  was  first  used  in  England  in  a  race  in  1871.  The  general 
features  of  the  sliding  seat  will  be  sufficiently  familiar.  Its  precise  mechani- 
cal value  has  been  very  ably  described  by  the  Eev.  E.  Warre,  of  Eton,  in  the 
following  words  : — 

'  Mechanically  speaking,  in  rowing  the  water  is  the  fulcrum,  the  boat  is 
the  weight  to  be  moved,  the  oar  is  the  lever,  and  the  man  applies  the  power. 
The  leverage  is  most  powerful  when  applied  at  right  angles  to  the  weight ; 
tout  in  the  problem  to  be  solved,  owing  to  the  motion  of  the  oar  itself  through 
the  water  and  the  motion  of  the  boat  through  the  water,  the  moment  at 
which  this  can  be  the  case  is  extremely  transient.  Could  any  satisfactory 
mechanism  be  devised  by  which  the  weight — that  is,  the  thowl  against  which 
he  rows — could  be  moved  forward  during  the  stroke,  while  the  oarsman  was 
still  in  the  position  to  exert  his  full  power  against  it,  we  might  expect  a  great 
increase  of  speed.  This,  however,  is  a  structural  problem  not  yet  solved.  But 
the  sliding  seat  in  some  measure  answers  the  purpose  by  enabling  the  oars- 
man or  sculler  to  continue  his  physical  effort  by  the  straightening  of  his 
legs  in  such  a  way  that  his  power  and  his  weight,  which  are  most  available 
^t  the  beginning  of  the  stroke,  are  operating  in  the  water  for  a  longer  period 
■during  each  stroke  than  could  be  if  he  were  on  a  fixed  seat.  The  gain  is 
much  less  than  that  of  a  moving  rowlock  would  be  because,  owing  to  the 
rising  of  the  knees  when  the  slider  is  forward,  a  man  cannot  obtain  a  much 
greater  reach  forward  than  he  could  on  a  fixed  seat.  It  is  when  the  body 
has  moved  up  towards  the  perpendicular,  and  the  water  has  already  been  got 
hold  of,  that  the  advantage  of  the  sliding  seat  begins.  As  the  slider  moves 
back,  the  uncoiling  of  the  human  spring,  which  is  imbedded  in  the  stretcher, 
can  go  on  with  undiminished  force  for  the  distance  of  the  slide,  when  the 
pressure  of  the  legs  ceases  and  the  weight  of  the  body  is  again  entirely  thrown 
on  the  seat.  The  mechanical  advantage  is  here  mostly  after  the  rowlock, 
and  that  is  the  least  valuable  part  of  the  stroke,  especially  in  a  light  boat. 
Still  the  gain  is  considerable,  as  it  enables  more  weight  and  more  strength 
to  be  applied  to  the  oar  for  a  longer  portion  of  the  stroke. 

'Further,  there  has  been  for  grown  men  a  physical  gain  in  that  the 
increased  length  of  stroke  enables  the  same  pace  to  be  attained  with  fewer 
strokes  per  minute.  The  pace  of  the  inferior  or  mediocre  crews  accordingly 
has  been  improved.  Moreover,  the  effort  of  springing  the  body  forward  to 
its  fullest  reach,  which  on  the  fixed  seat  was  necessary,  is  now  greatly  reduced 
by  the  mechanism  of  the  slide,  and  consequently  the  exertion  to  heart  and 
lungs  is  much  less.  This  is  a  gain  to  those  who,  by  reason  of  age  and  figure, 
.are  not  so  hthe  and  active  as  in  boyhood,  but  it  has  been  a  loss  to  pubhc 
school  crews,  who  could  make  up  formerly  by  pace  of  stroke  and  agihty 
for  their  inferiority  in  strength  to  men.'  ^ 

'  Health  Exhibition  Handhoohs,  vol.  x. 


582  HYGIENE 

The  sliding  seat  is  estimated  to  give  a  gain  of  about  18  in.  in  the  length 
of  the  stroke  upon  a  9  in.  slide. 

'The  shding  seat,'  writes  Mr,  Woodgate,  in  the  Badminton  Library- 
volume  on  Boating,  *  decidedly  relieves  the  abdominal  muscles  and  respi- 
ratory organs  during  the  recovery.  The  point  wherein  a  tiring  oarsman  first 
gives  way  is  in  his  recovery,  because  of  the  relative  weakness  of  the  muscles 
which  conduct  that  portion  of  the  action  of  the  stroke.  It  therefore  is  obvious 
that  any  contrivance  wliich  can  enable  a  man  to  recover  with  less  exertion 
to  himself  will  enable  him  to  do  more  work  in  the  stroke  over  the  whole 
course,  and  still  more  so  if  the  very  contrivance  which  aids  recovery  also 
gives  extra  power  to  the  stroke.' 

The  increase  in  speed  has  not  been  so  great  as  might  have  been  imagined.. 

Bowing  and  Sculling 

Eowing,  it  is  needless  to  say,  involves  the  pulling  of  one  oar  with  both- 
hands,  and  sculhng  the  pulhng  of  a  pair  of  sculls,  employing,  of  course,  one 
hand  to  each. 

The  details  of  the  stroke  in  rowing  should  be  weU  understood  in  order 
that  the  muscular  features  of  the  act  might  be  recognised  and  the  qualities 
of  a  good   stroke   appreciated.     The   following   description  of  the   rowing' 
stroke  by  the  Eev.  E.  Warre  is  precise  and  lucid,  and  can  hardly  be  improved 
upon : — 

'  The  moment  the  oar  touches  the  body  drop  the  hands  smartly  straight 
down,  then  turn  the  wrists  sharply  and  at  once  shoot  out  the  hands  in  a 
straight  line  to  the  front,  inclining  the  body  forward  from  the  thigh  joints 
and  simultaneously  bring  up  the  slider,  regulating  the  time  by  the  swmg 
forward  of  the  body  according  to  the  stroke.    Let  the  chest  and  stomach  come 
well  forward,  the  shoulders  be  kept  back,  the  inside  arm  be  straightened,  the 
inside  wrist  a  little  raised,  the  oar  grasped  in  the  hands,  but  not  pressed 
upon  more  than  is  necessary  to  maintain  the  blade  in '  its  proper  straight 
line  as  it  goes  back,  the  head  kept  up,  the  eyes  fixed  on  the  outside  shoulder 
of  the  man  before  you.     As  the  body  and  arms  come  forward  to  their  full 
extent,  the  wi-ists  having  been  quickly  turned,  the  hands  must  be  raised 
sharply,  and  the  blade  of  the  oar  brought  to  its  full  depth  at  once.     At  that 
moment,  without  the  loss  of  a  thousandth  part  of  a  secand,  the  whole  weight 
of  the  body  must  be  thrown  on  to  the  oar  and  the  stretcher  by  the  body- 
springing  back,  so  that  the  oar  may  catch  hold  of  the  water  sharply  and 
be  driven  through  it  by  a  force  unwavering  and  uniform.     As  soon  as  the 
oar  has  got  hold  of  the  water,  and  the  beginning  of  the  stroke  has  been 
effected  as  described,  flatten  the  knees,  and  so,  using  the  muscles  of  the  legs, 
keep  up  the  pressure  of  the  beginning  uniform  through  the  backward  motion 
of  the  body.     Let  the  arms  be  rigid  at  the  beginning  of  the  stroke.     When 
the  body  reaches  the  perpendicular,  let  the  elbows  be  bent  and  dropped 
close  past  the  sides  to  the  rear — the  shoulders  dropping  and  disclosing  the 
chest  to  the  front,  the  back,  if  anything,  curved  inwards  rather  than  outwards, 
but  not  strained  in  any  way.     The  body,  in  fact,  should  assume  a  natural 
upright  sitting  posture,  with  the  shoulders  well  thrown  back.    In  this  position 
the  oar  should  come  to  it  and  the  feather  commence.' 

Among  the  particulars  to  be  noted  in  the  stroke  are  the  following.  The 
back  should  be  set  stiff  and  must  not  yield  as  the  stroke  is  pulled.  It 
should  be  straight  while  the  chest  comes  well  forward.  The  whole 
trunk  should  swing  as  a  rigid  column  from  the  hips,  moA-ing  forwards  and 
backwards.     The  main  pull  of  the  arms  is  from  the  shoulders.     The  biceps- 


PHYSICAL  EDUCATION  583 

should  not  do  the  work  and  the  elbows  must  be  kept  well  to  the  side.  If 
this  latter  point  be  insisted  upon  the  stroke  can  scarcely  be  rowed  home  by 
the  arm  muscles.  When  an  oarsman  is  becoming  '  pumped '  it  is  in  the 
recovery  that  he  feels  the  strain.  He  fails  to  shoot  the  hands  forwards  from 
the  chest  the  moment  after  they  touch  that  point,  and  he  becomes  sluggish 
in  reaching  forward  to  take  a  fresh  hold  of  the  water. 

Sculling  is  in  all  essential  particulars  identical  with  rowing,  so  far  as  the 
muscular  movements  are  concerned.  It  involves,  however,  more  precision, 
more  skill,  more  practice.  The  sculler  has  to  acquire  the  art  of  balancing 
himself,  and  a  failure  to  ever  do  this  well  leads  often  to  a  fixed  bad  style, 
which  no  practice  appears  to  remove. 

The  remarks  already  made  apply  to  rowing  and  to  sculling  in  its  highest 
developments,  but  in  all  essentials  they  apply  to  the  ordinary  pleasure  boat. 
In  such  a  boat  there  is  no  need  of  great  speed,  there  is  no  sliding  seat  to 
embarrass  an  already  complex  movement.  The  boat  is  steady  enough,  and 
the  oarsman  can  devote  all  his  energies  to  the  pulling. 

It  is  much  to  be  regretted  that  many  boating  men  and  women  are  content 
simply  to  pull  the  boat  along.  They  care  nothing  about  the  order  of  their 
going,  they  are  perfectly  indifferent  as  to  style,  and  are  content  for  the  rest 
of  their  days  to  row  badly.  To  row  correctly  is  to  row  with  ease.  The  better 
the  style,  the  easier  the  movement  and  the  better  the  pace.  The  better  the 
style,  moreover,  the  more  complete  and  perfect  is  the  exercise.  Bad  rowing 
is  often  bad  exercise,  and  to  row  in  the  atrocious  manner  with  which  some 
holiday  makers  have  made  us  familiar  is  to  indulge  in  a  pursuit  of  very 
doubtful  utility. 

As  an  exercise,  sculling  may  be  considered  to  be  better  than  rowing.  To 
all  ordinary  individuals  boating  should  imply  a  knowledge  of  sculling,  and  no 
person  should  be  content  with  the  capacity  to  pull  one  oar. 

Sculling  involves  a  more  even  employment  of  all  the  muscles  of  the  body  ; 
one  side  of  the  body  is  not  more  extensively  employed  than  is  the  other ; 
there  is  no  disposition  to  rotate  or  '  screw '  the  back  or  to  pull,  as  it  were, 
from  one  side.  In  sculling,  the  muscles  of  the  two  sides  of  the  body  are 
equally  employed  and  the  exercise  has  the  great  merit  of  being  perfectly 
symmetrical. 

The  Muscles  Involved 

Let  us  imagine  a  man  sculling  in  an  ordinary  gig  with  a  fixed  seat.  He 
takes  a  good  grasp  of  the  sculls,  using  fully  the  muscles  of  the  hand  and  of 
the  flexor  side  of  the  forearm.  He  throws  the  hands  forwards  to  take  the 
stroke,  using  the  extensor  muscles  of  the  arm,  the  pectorals,  the  serratus 
magnus  and  such  scapular  muscles  as  draw  the  upper  limb  forwards.  The 
body  is  at  the  same  time  thrown  forwards  by  the  contraction  of  the  abdominal 
muscles,  the  psoas  and  iliacus,  and  some  of  the  anterior  femoral  muscles. 
The  whole  back  is  kept  stiff,  and  the  trunk  swings  forwards  from  the  hip 
joints  only.  The  sculls  are  now  drawn  through  the  water,  the  muscles  of  the 
upper  arm  contract,  together  with  the  posterior  scapular  muscles  and  the 
latissimus  dorsi.  The  main  agent,  however,  in  effecting  the  stroke  is  provided 
by  the  great  mass  of  the  extensor  muscles  of  the  back  and  by  the  powerful 
glutei  muscles.  The  man  rows  with  his  back,  not  with  his  arms.  In  pulling  he 
presses  the  feet  against  the  stretcher,  contracting  nearly  all  the  muscles  of  the 
lower  limb.     In  feathering  he  calls  into  action  the  extensors  of  the  forearm. 

Inasmuch  as  the  head  is  kept  erect  and  the  chest  well  thrown  forward, 
it  will  be  seen  that  sculling  and  rowing  do  actually  engage  all  the  main 
muscles  of  the  body. 


584  HYGIENE 

If  a  sliding  seat  be  employed,  then  the  exercise  is  still  more  complete  and 
uniform,  for  the  muscles  of  the  lower  limb  are  used  to  a  still  greater  extent 
in  drawing  the  body  forwards  and  in  shooting  it  back.  Still  the  main  strain 
in  rowing  and  sculling  falls  upon  the  muscles  of  the  back  and  hip. 

The  mechanics  of  sculling  can  be  readily  studied  in  Muybridge's  ingenious 
photographs,  and  reference  may  be  made  to  the  description  in  Keating's 
'  Cyclopaxlia  '  (vol.  iv.,  photo,  iv.). 

The  idea,  often  expressed,  that  boating  involves  the  use  of  the  arms  only 
is  even  more  ridiculous  than  the  equally  common  assertion  that  bicycling  in- 
volves the  use  of  the  legs  only.  A  muscular  man  going  into  hard  training 
for  rowing  will  find  that  his  biceps  muscles  will  actually  diminish  in  size. 

The  bad  oarsman  rows  or  sculls  with  his  biceps.  Such  an  individual  is 
often  to  be  seen  in  the  London  parks.  He  sits  with  his  back  limp  and 
arched,  and  very  probably  with  his  legs  tucked  away  under  the  thwart.  He 
leans  forwards  to  take  the  stroke,  grasps  the  water,  and  pulls  the  sculls 
through  simply  by  the  action  of  the  muscles  of  the  upper  limb  and  mainly  by 
the  biceps.  He  does  not  extend  the  trunk  beyond  the  perpendicular,  and  the 
manner  in  which  he  projects  his  elbows  has  been  caricatured  often  enough. 
The  movements  he  executes  are  not  those  of  the  oarsman,  and,  although  the 
half-hour's  pull  may  be  better  than  no  exercise  at  all,  it  tends  to  make  the 
individual  round-shouldered  and  clumsy,  and  to  develop  the  muscles  of  his 
arms  to  the  sacrifice  of  all  the  others. 

The  Adaptabilities  of  Boating 

Boating  properly  carried  out  must  remain  one  of  the  most  perfect  forms  of 
muscular  exercise  we  possess.  The  degree  of  muscular  effort  involved  can 
be  regulated  to  any  degree,  and  a  girl  of  eleven  may  scull  with  as  much  style 
as  an  athlete  of  twenty. 

Boating  is  an  exercise  which  does  not  cause  breathlessness.  An  elderly 
man  can  pull  a  boat  day  after  day  on  a  long  river  tour  without  difficulty, 
provided  the  pace  be  moderate,  when  he  would  be  utterly  out  of  breath  on 
ascending  a  hill  or  even  a  great  flight  of  stairs.  It  can  be  indulged  in  by 
individuals  with  weak  hearts  and  weak  lungs,  provided,  of  course,  that  the 
pace  is  strictly  limited. 

Boating  is  not  suited  for  the  subjects  of  hernia  nor  for  those  with  a  disposi- 
tion to  hernia.  The  posture  assumed  in  leaning  forwards  to  take  the  stroke  and 
the  contraction  of  the  abdominal  muscles  at  the  same  time  favour  a  hernial 
protrusion. 

Boating,  however,  tends  to  develop  and  to  strengthen  the  abdominal 
muscles  and  to  lessen  the  size  and  improve  the  tone  of  the  pendulous  abdo- 
men not  uncommon  after  middle  life. 

Eowing  and  sculling  are  admirable  exercises  for  girls  and  women. 
Ladies  should  row  without  corsets,  or  with  corsets  of  the  slenderest  possible 
make.  Perhaps  no  exercise  is  better  suited  to  remedy  the  muscular  defects 
which  are  conspicuous  in  the  gentler  sex.  It  expands  the  chest,  strengthens 
the  back,  and  gives  tone  to  the  muscles  of  the  abdomen. 

Boating  should  be  recommended  with  certain  precautions,  and  of  course 
in  properly  selected  cases  to  the  subjects  of  lateral  curvature  of  the  spine, 
especially  to  those  who  exhibit  the  deformity  in  its  early  condition. 

Such  individuals  should  scull,  not  row.  All  those  who  take  to  boating 
should  first  learn  to  swim.  Boys  may  begin  to  learn  to  row  at  six  and  girls  at 
eight.   It  is  a  matter  of  the  utmost  importance  that  the  learner  be  well  taught. 

It  is  well  to  begin  in  a  light  half-outrigged  boat  which  will  seat  two,  the 


PHYSICAL  EDUCATION  585 

teacher  and  the  pupil.  The  water  should  be  smooth.  The  pupil  should 
begin  by  pulling  one  scull  only,  rowing  for  equal  periods  upon  the  right  and 
the  left  side.  He  will  in  this  way  learn  the  rough  details  of  the  stroke  and 
the  rhythm  of  the  movement.   He  should  from  the  first  be  made  to  keep  time. 

The  exercise  with  one  scull  should  be  brief,  and  the  sooner  the  pupil 
takes  to  both  sculls  the  better.  There  is  usually  much  difficulty  with  the 
left  hand. 

As  soon  as  the  pupil  can  scull  moderately  well  he  should  row  behind  a 
good  oarsman,  and  in  this  way  he  will  pick  up  the  swing  of  the  movement 
and  the  proper  points  of  the  stroke. 

Sea  Boioing  is  inferior  to  river  rowing  as  an  exercise  :  the  boat  is  heavy, 
the  gunwale  is  high  out  of  the  water,  the  stroke  is  short,  and  the  movement 
is  not  susceptible  of  the  finish  possible  in  a  river  boat. 

Those  who  have  rowed  much  on  the  sea  will  probably  never  row  well  on 
the  river.  The  exercise  involves  more  muscular  exertion,  which  is,  however, 
of  a  rougher,  more  clumsy  and  unfinished  kind.  To  row  a  sea  boat  the 
individual  must  be  strong.  Sea  rowing  is  not  well  adapted  for  children  or 
for  those  who  are  muscularly  feeble  ;  and,  while  as  an  exercise  it  has  admirable 
points,  it  should  be  borne  in  mind  that  on  fresh  water  alone  is  the  pursuit  of 
boating  capable  of  assuming  its  most  perfect  form. 

Canoeing 

For  the  purpose  of  the  present  paper  canoes  may  be  considered  to  belong 
to  two  classes — the  Eob  Eoy  canoe  and  the  Canadian. 

In  the  former  the  canoeist  sits  amidships  with  his  lower  limbs  extended 
straight  upon  the  floor  of  the  craft.  The  paddle  is  of  considerable  length, 
and  has  a  blade  at  either  end.  The  canoeist  holds  it  about  breast  high,  and 
drives  first  one  blade  through  the  water  and  then  the  other.  His  back  is 
supported  by  a  rest. 

In  this  form  of  canoeing  the  muscular  exertion  involved  is  limited  to  the 
muscles  of  the  arms  and  shoulders,  including  the  pectorals,  trapezius, 
serratus  magnus,  and  latissimus  dorsi.  The  muscles  of  the  neck  and 
upper  part  of  the  back  are  concerned,  but  the  body  below  the  thorax  is 
practically  motionless.  The  exercise,  therefore,  is  one  of  limited  muscular 
applicability. 

The  exercise  is  good  for  those  who  wish  to  develop  the  arms  or  who  fi'om 
some  deformity  or  defect  are  unable  to  use  the  lower  limbs.  It  is  not  an 
exercise  to  be  recommended  to  those  who  aim  at  developing  the  whole 
muscular  system  or  who  are  the  subjects  of  any  spinal  weakness. 

In  the  Canadian  canoe  as  adapted  for  use  in  England  the  canoeist  sits 
at  the  extreme  stern,  either  on  the  floor  or  upon  a  seat  nearly  flush  with  the 
gunwale,  and  with  his  feet  on  a  stretcher.  He  has  a  short  paddle  with  a 
single  blade.  He  paddles  upon  one  side  of  the  craft  only  and  steers  by 
manipulating  the  blade  at  the  completion  of  each  stroke.  In  all  but  the 
smallest  form  of  Canadian  canoe  a  second  seat  is  provided  close  to  the  prow 
for  a  second  paddle.  The  fore  paddle  may  be  shorter,  and  is  worked  at  a 
diminished  advantage,  and  the  steering  of  the  craft  must  still  remain  with 
the  paddle  in  the  stern. 

The  Canadian  canoe  involves  a  much  more  complete  form  of  exercise 
than  does  the  Eob  Eoy  canoe.  The  canoeist  has  no  support  for  his  back. 
He  must  keep  himself  erect  by  muscular  effort.  In  effecting  the  stroke  he 
employs,  not  only  the  muscles  of  the  upper  limb,  but  also  the  muscles  of  the 
trunk.  The  whole  body  undergoes  some  rotation  in  the  vertical  axis  at  each 
stroke.     After  long  paddling,  a  sense  of  exhaustion  is  felt  in  the  back 'and 


58G  HYGIENE 

about  the  loins,  but  not  in  the  arms.  The  canoeist  has  also  to  balance  him- 
self, and  as  the  Canadian  canoe  is  carvel-built  and  keelless  this  involves 
some  extra  muscular  expenditure.  The  after  paddler  can  make  consider- 
able use  of  his  legs,  moreover  ;  a  help  which  is,  to  a  great  extent,  denied  to 
the  paddler  in  the  bow  of  the  canoe.  The  canoeist  should  change  his  side 
fi'om  time  to  time — in  other  words,  should  not  paddle  for  too  long  a  time  at 
a  stretch  upon  one  side.  Paddling  upon  one  side  tends  to  produce  much 
lateral  bending  of  the  vertebral  column. 

This  exercise  is  not  well  adapted  for  the  weakly,  nor  for  those  who  have 
weak  backs  and  a  disposition  to  lateral  curvature.  For  the  robust  it  is  ad- 
mirable, and  forms  a  very  pleasant  variation  to  rowing  or  sculling. 

A  voyage  in  a  canoe  usually  involves  exercise  of  the  most  varied  kind : 
there  are  hard  paddling  against  a  stream,  nervous  steering  down  a  rapid,  the 
dragging  of  the  craft  over  shallows  and  past  milldams,  and  the  very  arduous 
task  of  making  a  way  through  thick  rushes  and  weeds. 

Cycling 

The  history  of  athletic  sports  provides  probably  no  more  remarkable 
feature  than  is  afforded  by  the  introduction  and  development  of  cychng. 
Twenty  years  ago  the  bicycle  was  unknown  in  this  comitry.  Even  fifteen 
years  ago  riders  upon  bicycles  were  regarded  as  little  other  than  acrobats 
and  mountebanks.  Within  so  short  a  period  this  form  of  athletic  exercise 
has  developed  with  almost  incredible  rapidity  and  with  phenomenal  vigour. 
Cyclists  are  now  to  be  counted  in  tens  of  thousands,  the  sport  has  been  taken 
up  by  individuals  of  all  ages  and  in  all  stations  of  life,  and  has  been  enthu- 
siastically patronised  by  women  as  well  as  by  men. 

The  history  of  cycling  is  very  admirably  given  by  Mr.  G.  Lacy  Hillier — 
himself  a  well-known  rider^n  the  Badminton  volume  on  '  Cycling.' 

The  general  features  of  the  cycles  now  in  use  must  be  familiar  enough. 
There  are  two  forms  of  bicycle,  the  '  Ordinary  '  and  the  '  Safety.'  The 
Ordinary  represents  the  earher  pattern.  In  this  machine  the  wheel  is  driven 
by  the  direct  action  of  the  pedals.  The  size  of  the  wheel  depends  upon  the 
height  or  '  the  reach  '  of  the  individual  rider.  A  diameter  of  50  inches 
will  represent  an  average  size.  With  this  wheel  the  rider  steers,  and  upon 
it  he  balances  himself.  In  propelling  this  machine  there  is  no  waste  of 
muscular  force.  The  rider  is  placed  directly  '  over  his  work,'  or,  as  it  would 
be  expressed  with  reference  to  other  exercises,  '  close  to  his  work.'  No  power 
is  lost  upon  cog  wheels  and  chains,  and  the  weight  of  the  body  can  be 
admirably  utihsed  in  aiding  progression. 

The  Safety  bicycle  represents  the  machine  of  the  immediate  future.  The 
varieties  of  this  cycle  are  legion,  but  the  form  most  commonly  used  is  founded 
upon  what  is  known  as  '  the  Eover  '  pattern. 

The  Safety  bicycle  is  represented  by  a  machine  with  the  following  cha- 
racters. The  two  wheels  are  comparatively  small,  and  are  either  of  equal 
size  or  are  nearly  so.  The  diameter  of  each  will  be  about  28  or  30  inches. 
The  front  wheel  is  the  steering  wheel,  and  with  it  the  handles  are  coimected  ; 
its  movement,  so  far  as  the  act  of  steering  is  concerned,  is  effected  through 
a  nearly  horizontal  joint,  'the  head.'  The  hinder  wheel  is  the  driving 
wheel.  It  is  not  propelled  by  the  direct  action  of  the  pedals.  The  pedals 
act  upon  a  small  cogged  or  toothed  wheel  carrying  a  chain,  and  through  this 
chain  the  movement  is  communicated  to  the  rear  wheel.  The  rider  sits 
directly  over  the  chain  wheel  to  which  the  pedals  and  their  cranks  are 
attached,  and  is  therefore  placed  between  the  two  running  wheels  of  the 


PHYSICAL   EDUCATION  587 

bicycle.  The  machine  is  said  to  be  '  geared.'  If  the  two  pulley  wheels  with 
which  the  chain  is  connected  are  of  equal  size  the  machine  is  said  to  be 
'  level  geared.'  In  such  case  one  complete  revolution  of  the  pedal  involves 
one  complete  revolution  of  the  driving  wheel.  If  the  pulley  wheels  with 
which  the  chain  is  connected  are  of  unequal  size,  and  if  the  wheel  con- 
nected with  the  pedal  is  the  larger,  the  machine  is  said  to  be  '  geared  up.' 
In  such  case  the  pedal  revolutions  are  fewer  than  the  revolutions  of  the 
driving  wheel.  The  Safety  bicycle  is  usually  '  geared  up  to  54  ; '  that  is  to 
say,  the  relation  between  the  wheel  moving  the  chain  and  the  wheel  moved 
by  it  is  such  that  the  driving  wheel,  which  has  an  actual  diameter  of  28 
inches,  revolves  at  each  complete  turn  of  the  pedal  through  a  range  of 
movement  equal  to  that  made  by  one  complete  revolution  of  a  wheel  with 
a  diameter  of  54  inches. 

Some  tricycles  are  '  geared  down,'  by  which  term  is  implied  the  fact 
that  the  hinder  of  the  two  pulley  wheels  is  the  smaller,  and  therefore  more 
than  one  revolution  of  the  pedal  is  required  to  produce  one  revolution  of  the 
driving  wheel. 

In  this  question  of  gearing  it  must  be  remembered  that  one  factor  of  the 
equation,  viz.  the  strength  of  the  rider,  is  a  fixed  quantity,  and  that  either 
speed  or  power  must  be  sacrificed  when  the  other  conditions  of  the  problem 
are  varied.  If  the  machine  be  geared  up,  the  rider  can  make  fewer  revolutions 
of  the  pedal  than  would  be  required  if  the  gearing  were  level,  but  he  must 
employ  more  force.  On  the  other  hand,  if  the  machine  be  geared  down  an 
increased  number  of  movements  of  the  foot  is  required  ;  but  the  amount  of 
force  involved  is  much  less.  A  young  man  of  light  weight  or  an  individual 
of  feeble  muscular  power  may  prefer  to  use  his  legs  with  greater  activity  pro- 
vided he  can  employ  a  lesser  degree  of  muscular  effort.  Such  an  individual 
may  prefer  a  cycle  geared  low.  A  man  of  more  advanced  years,  of  more  than 
average  weight,  and  of  considerable  muscular  strength,  would  probably  be 
glad  to  expend  an  undue  amount  of  force  on  each  stroke  of  the  foot  rather 
than  to  feel  the  necessity  of  moving  his  pedals  rapidly.  Such  a  rider 
would  select  a  machine  with  a  higher  gearing. 

While  a  roadster  Safety  will  usually  be  geared  to  54,  a  racer  Safety  of  the 
same  type  may  be  geared  to  63. 

The  Humber  Eoadster  tricycle  ('  gents'  light  cripper ')  is  geared  to  57  in 
the  maker's  catalogue,  the  ladies'  tricycle  of  the  same  pattern  to  54,  the 
corresponding  racer  cripper  to  63. 

The  weight  of  a  racing  Safety  may  be  reduced  to  201b.  complete.  The 
weight  of  a  racing  tricycle  (Humber  Cripper)  is  given  as  30  lb.  A  roadster 
Safety  weighs  from  about  36  to  42  lb.  A  Eoadster  tricycle  may  scale  from 
45  to  66  lb. 

The  tricycle  is  well  represented  by  the  excellent  machine  known  as  the 
Humber  Cripper.  In  this  tricycle  the  front  or  steering  wheel  has  a  diameter 
of  24  in.,  the  two  driving  wheels  of  30  in.  A  single  chain  is  employed.  The 
saddle  is  placed  well  over  the  pedals,  and  the  machine  in  all  general  features 
is  based  upon  the  mechanical  lines  of  a  Safety  bicycle.  The  introduction  of 
the  ingenious  ball-bearmg  joint  to  cycles  of  all  kinds  has  reduced  the  amount 
of  friction  in  running  to  a  minimum. 

The  Safety  bicycle  if  taken  against  any  obstacle  sufficient  to  stop  the  front 
wheel  merely  falls  over  on  its  side.  The  rider's  feet  are  so  close  to  the 
ground  that  it  needs  no  very  great  inclination  of  the  machine  to  enable  him 
to  bring  one  foot  to  the  ground,  and  so  prevent  a  fall. 

The  term  '  Safety '  is  well  merited.  An  accident,  when  it  occurs,  is 
probably  the  fault  of  the  rider  alone,  and  is  inexcusable.     There  are  many 


588 


HYGIENE 


Avho  have  ridden  these  machines  for  years  over  some  thousands  of  miles  of 
road,  and  who  have  yet  never  met  with  what  may  be  termed  an  accident,  or 
even  a  nasty  fall. 

One  disadvantage  which  has  been  urged  against  all  cycles  is  that  of 
vibration.  There  is  no  doubt  that  long-continued  vibration  communicated 
to  the  body  is  injurious.  It  is  unpleasant,  it  induces  fatigue,  and  leads  to 
earlier  exhaustion  of  the  muscles. 

The  effects  of  vibration  are  less  felt  in  the  young,  and  upon  the  bodies  of 
lads  under  eighteen,  who  still  possess  many  epiphyseal  cartilages,  a  long- 
continued  vibration  may  tell  but  little.  But  in  older  individuals,  in  those 
Avhose  bodies  have  become  more  rigid  in  the  process  of  development,  and 
especially  in  persons  with  a  sensitive  nervous  system,  vibration  has  certainly 
an  unfavourable  effect.  They  return  from  a  long  ride  over  rough  roads  with  an 
imdue  sense  of  fatigue — they  feel  '  shalvcn,'  the  back  aches,  the  arm  muscles 
are  a  little  tremulous,  and  there  often  follow  a  headache  and  a  sleepless  night. 

Vibration  has  been  to  a  large  extent  overcome  by  the  use  of  '  cushion  '  or 
'  pneumatic  '  tyres,  or  by  means  of  a  suspending  spring,  such  as  has  been  intro- 
duced, with  the  greatest  success,  in  what  is  known  as  the '  Whippet '  bicycle. 
The  Whippet  machine  may  be  said  to  bear  the  same  relation  to  the  usual 
Safety  bicycle  which  a  cart  witli  springs  bears  to  one  without  springs. 

The  following  records  will  give  an  idea  of  the  possible  speed  which  can 
be  attained  on  a  cvcle: — 


- 

Bicycle 

Tricycle 

h.  m.     s. 

h.  m.    s. 

Half-mile 

1     8 

1  17 

One  mile  . 

2  20 

2  37 

Three  miles 

7  40 

8     6 

Ten  miles 

26  40 

28  13 

Twenty  miles  . 

55     0 

56  40 

Fifty  miles 

2  25  26 

2  38  44 

Hundred  miles 

5  50     5 

6    9  26 

Cycling  as  an  Exercise 

Bicycling. — A  ride  upon  a  bicycle  involves  not  only  an  admirable  muscular 
exercise,  but  it  involves  of  necessity  exertion  in  the  open  air.  The  exercise  is 
continuous  and  not  intermittent ;  it  can  be  regulated  to  any  degree,  and  can 
be  indulged  in  equally  by  the  athlete  and  the  weakling. 

He  who  owns  a  bicycle  has  at  his  command  one  of  the  most  admirable 
and  certainly  one  of  the  least  expensive  means  of  travelhng.  He  is  de- 
pendent solely  upon  himself,  and  can  without  difficulty  travel  fifty  miles  a  day. 
No  horse  could  compete  in  endurance  and  in  long  distances  with  the  bicycle 
rider. 

Cycling  has  undoubtedly  done  more  than  has  any  other  form  of  physical 
exercise  to  improve  the  bodily  condition  of  the  city  clerk  and  the  shop  assistant. 
The  lad  who  is  pent  up  in  a  close  office  all  day  has  now  no  difficulty 
in  finding  a  means  for  well  occupying  the  summer  evening  or  the  few  hours 
at  his  disposal  before  the  work  of  the  day  begins.  He  has  merely  to  mount 
his  bicycle  and  in  an  hour  he  is  ten  miles  away  from  the  din  of  city  life,  and 
is  breathing  a  clearer  and  brisker  air.  He  who  is  an  early  riser  can  in  the 
summer  months  well  manage  a  twenty-mile  ride  before  breakfast. 

Unhke  the  player  of  cricket  and  football  or  the  rowing  man,  the  cyclist  is 
■dependent  upon  no  one  but  himself.    His  means  of  exercise  is  always  at  hand, 


PHYSICAL  EDUCATION  580 

and  lie  can  occupy  a  spare  half-hour  or  the  entire  afternoon  with  the  same 
amount  of  preparation. 

The  specific  features  of  the  exercise  of  bicychng  may  best  be  reviewed  by- 
discussing  the  objections  which  have  been  urged  against  the  sport. 

1.  It  is  said  to  be  dangerous.  This  objection  without  doubt  applied  to  the 
high-wheel  bicycle,  but  it  can  scarcely  be  said  to  be  just  as  regards  the  more 
modern  machine — the  Safety.  The  rider  rides  with  his  feet  but  a  few  inches 
from  the  ground.  If  he  is  falhng  he  has  simply  to  step  off.  The  machine 
cannot  turn  *  head  over  heels,'  it  can  merely  fall  upon  its  side.  The  brakes 
now  applied  to  these  machines  are  so  strong  that  they  can  bring  the  bicycle 
to  a  standstill  in  a  moment. 

The  most  serious  accidents  have  occurred  in  riding  through  crowded 
streets,  and  unless  a  rider  is  perfect  at  his  work,  and  is  as  quick  as  a  hare,  he 
is  merely  foolhardy  if  he  attempts  to  ride  through  a  very  busy  thoroughfare. 

Bicycling  may  be  said  to  be  less  dangerous  than  riding  on  horseback, 
especially  when  the  distances  travelled  are  taken  into  account,  and  to  be 
certainly  less  risky  than  skating. 

2.  A  second  objection  to  the  bicycle  is  that  it  is  a  very  partial  exercise, 
and  that  it  involves  the  use  of  the  muscles  of  the  legs  only.  It  may  be  said 
at  once  that  the  first  difficulty  of  bicycle  riding  is  not  the  propelling  of  the 
machine,  but  the  maintenance  of  a  proper  balance.  The  learner  after  his 
half-hour  exercise  will  not  complain  of  aching  in  his  legs,  but  of  aching 
in  his  arms  and,  to  a  lesser  degree,  in  his  back.  The  beginner  is  apt  to  believe 
that  the  whole  strain  of  the  exercise  comes  upon  the  forearms.  In  other 
words,  the  grip  of  the  steering  wheel  and  the  easy,  immediate,  and  complete 
control  of  that  part  of  the  machine  are  the  first  principles  in  bicycle  riding. 
To  preserve  the  upright  position  many  muscular  movements  are  required, 
and  in  these  practically  all  the  muscles  of  the  trunk  are  concerned. 

In  course  of  time  balancing  becomes  not  only  easy  but  quite  automatic  ; 
and  while  it  is  true  that  the  upright  posture  is  finally  retained  with  a  very 
modified  amount  of  muscular  exertion,  still  an  extensive  series  of  muscles 
are  involved  even  if  the  pov^er  exerted  be  slight. 

To  sit  upright  for  some  hours  without  any  support  for  the  back  is  not  a 
quite  insignificant  exercise,  and  after  a  long  ride  the  bicyclist  finds  that  he 
has  been  doing  more  with  his  back  than  he  thought. 

So  far  as  the  movements  of  the  legs  are  concerned,  an  opinion  of  bicycling 
as  a  muscular  exercise  should  not  be  formed  by  observing  the  riders  one 
often  sees  in  the  streets  of  a  great  city  on  Sunday  or  on  the  suburban  roads 
on  a  Bank  holiday. 

The  ill-taught  or  inexperienced  rider  rides  from  his  hips  ;  he  moves  his 
lower  limbs  like  pistons  ;  his  action  is  extreme ;  his  ankle  is  fixed  ;  his  foot 
and  leg  move  as  one. 

Pedalling  is,  to  a  great  extent,  a  matter  of  the  ankle-joint.  The  more  the 
ankle-joint  is  employed  the  more  is  muscular  power  economised,  and  the 
more  graceful  is  the  rider's  movement. 

While  bicycling  does  certainly  involve  in  the  main  the  muscles  of  the 
lower  extremities,  it  at  the  same  time  gives  excellent  employment  to  the 
muscles  of  the  upper  limb  (especially  of  the  forearm)  and  to  the  muscles  of 
the  trunk. 

Cycling  does  not  tend  to  develop  the  chest  or  exercise  the  great  muscles 
passing  from  the  trunk  to  the  upper  limb,  and  herein  lies  the  defect  of  the 
sport  as  an  exercise.  It  cannot  be  recommended  as  a  predominating  mode 
of  exercise  to  a  tall,  lanky  lad  with  a  narrow  chest  and  a  stooping  back. 
Such  an  individual  should  take  to  rowmo'  and  leave  the  wheel  alone. 


590  HYGIENE 

3.  In  the  tliirtl  place  it  is  said  that  bicycle  riding  induces  a  very  per- 
nicious posture  of  the  body — a  posture  which  has  been  well  caricatured  by  Du 
Maurier  in  the  pages  of  '  Punch.'  The  posture  complained  of  can  be  seen  any 
day  among  those  who  hire  a  bicycle  now  and  then  for  an  hour  and  tear  wildly 
through  the  streets  thereon.  The  rider  is  leaning  so  far  forwards  as  to  have 
his  body  nearly  horizontal.  His  back  is  bowed  and  arched,  his  elbows  stick 
out  like  the  limbs  of  a  startled  cat,  his  chest  is  almost  upon  the  handle  bar, 
and  his  chin  is  thrust  well  ahead. 

This  attitude  is,  to  some  extent,  a  necessity  upon  the  racing  track,  and 
there  is  no  doubt  that  it  is  practically  essential  in  riding  at  the  highest  pos- 
sible speed. 

For  riding  upon  the  road  it  is  ridiculous  and  as  out  of  place  as  the  posture 
of  a  jockey  at  the  finish  of  a  horserace  would  be  in  an  individual  taking  a 
canter  in  Eotten  Eow. 

This  absurd  attitude  when  assumed  by  riders  on  the  road  may  be  put 
down  in  part  to  sheer  ignorance,  in  part  to  bad  teaching,  and  in  part  to  a 
foolish  imitation  of  the  racing  man.  It  is  unnecessary,  inelegant,  and  dis- 
tinctly injurious. 

The  rider  should  sit  quite  upright,  with  his  back  straight  and  with  the 
upper  part  of  the  body  as  still  as  possible.  The  head  should  be  erect,  the 
shoulders  well  thrown  back,  and  the  elbows  at  the  sides.  He  should  sit, 
moreover,  well  to  the  back  of  his  saddle,  and,  as  one  writer  expresses  it, '  push 
out  in  front,  using  the  saddle  to  push  from.'  The  handles  of  the  machines 
are  now  made  so  as  to  render  a  perfectly  erect  position  possible ;  and  in 
ordering  a  machine  it  is  important  that  this  matter  of  the  handles  should 
be  attended  to. 

There  is  no  doubt  that  some  riders  who  have  been  utterly  careless  of  their 
attitude  have  to  thank  the  bicycle  for  rounded  shoulders  and  a  stooping  back. 

4.  It  is  said  that  in  cycling  injurious  pressure  is  brought  to  bear  upon 
the  perinfeum,  and  that  perinseal  abscess,  urinary  fistula,  and  other  troubles 
have  resulted  therefrom.  The  writer  has  not  been  able  to  find  any  evidence 
to  support  this  assertion. 

It  is  possible  that  cycling  may  lead  to  mischief  if  practised  by  a  patient 
■udth  an  inflamed  urethra  ;  it  is  conceivable  that  it  may  act  injuriously  in  the 
subjects  of  urethral  stricture  and  enlarged  prostate.  For  even  this  last- 
named  possibihty  there  is  very  little  scientific  support.  Among  tricycle 
riders  the  writer  is  acquainted  with  more  than  one  subject  of  prostatic,  hyper- 
trophy, and  by  such  individuals  he  has  been  assured  that  cychng  causes  no 
aggravation  of  such  symptoms  as  they  present.  In  the  advanced  stages  of 
prostatic  trouble  in  elderly  men,  when  vesical  symptoms  are  present,  cycHng 
could  scarcely  be  practised. 

In  perfectly  healthy  individuals  it  may  be  stated  that  cycling  does  not 
produce  an  injurious  degree  of  pressure  upon  the  perinteum. 

In  the  modern  saddle  a  suspended  slip  of  leather  is  the  only  part  which 
comes  in  actual  contact  with  the  perinasum.  No  metal-work  can  cause  direct 
pressure  upon  that  part. 

Any  discomfort  about  the  perineum  in  riding  is  probably  due  either  to 
a  form  of  saddle  iU- adapted  to  the  individual  rider,  or  to  a  bad  attitude 
assumed  in  riding. 

The  habit  of  stooping  forwards,  which  has  been  already  condemned,  brings 
the  perinseum  unduly  upon  the  saddle,  and  for  this  reason,  if  for  no  other, 
the  attitude  is  to  be  strongly  opposed. 

In  riding,  the  weight  of  the  body  rests  upon  the  tuberosities  of  the  ischia. 
These  points  alone  should  bear  the  pressure. 


PHYSICAL  EDUCATION  591 

Many  bicyclists  wear  suspensory  bandages  on  the  ground  that  the  testes 
are  occasionally  pressed  between  the  body  and  the  saddle.  Such  a  pre- 
caution is  unnecessary  if  the  rider  will  make  up  his  mind  to  sit  his  maciiine 
properly. 

It  is  needless  to  say  that  long- continued  pressure  upon  the  tuber  ischii 
may  lead  to  some  pain  along  the  long  scrotal  nerve  and  may  induce  an 
enlargement  of  the  bursa  over  that  process  of  bone. 

The  circumstance  is,  however,  very  rare,  and  is  no  more  likely  to  occur 
after  cycling  than  it  is  after  daily  riding  in  a  third-class  railway  carriage. 

5.  Cycling  is  accused  of  producing  varicose  veins  in  the  leg,  and  hernia. 
The  case  of  the  first-named  affection  is  considered  elsewhere,  and  need  not 
be  again  dealt  with. 

With  regard  to  hernia  there  is  little  to  add  to  what  has  been  already  said, 
except  to  point  out  one  fact.  It  is  true  that  in  easy  riding  the  abdominal 
muscles  are  but  little  used,  and  that,  therefore,  httle  pressure  is  brought  to 
bear  upon  the  abdominal  viscera. 

Indeed,  in  ordinary  riding  the  abdominal  muscles  have  singulary  little  to 
■do.  This  circumstance  may  appear  to  render  bicycling  a  suitable  exercise 
for  those  who  are  disposed  to  hernia.  It  must,  however,  be  noted,  on 
the  other  side,  that  the  attitude  of  the  rider  tends  to  so  relax  the  tissues 
about  the  hernial  orifices  as  to  render  the  circumstances  favourable  for  the 
■descent  of  a  hernia.  "When  the  rider  '  puts  on  pace  '  in  racing  or  in  avoid- 
ing an  obstacle  he  leans  forwards,  throws  his  abdominal  muscles  into  action, 
and  places  himself  in  a  condition  certainly  favourable  for  the  formation  of  a 
rupture.  In  '  mounting '  also  a  sudden  and  pronounced  contraction  of  the 
belly  muscles  is  called  for,  and  that,  too,  while  the  individual's  body  is 
flexed. 

It  may  be  said,  therefore,  that  bicycle  riding  should  be  avoided  by  those 
who  have  weak  inguinal  regions  or  a  disposition  to  hernia,  and  that  it  should 
not  be  practised  by  the  actually  ruptured. 

Bicycling  is  well  suited  for  the  young,  nimble,  and  active  ;  it  is,  however, 
not  ill-adapted  to  the  middle-aged  and  to  those  who  have  lost  the  elasticity 
of  youth.  A  man  of  forty,  weighing  13  or  even  14  stone,  may  take  to 
bicychng  as  an  exercise,  may  attain  considerable  proficiency  as  a  rider,  and 
may  derive  unmixed  benefit  from  the  pursuit.  He  needs  be  nimble  enough 
to  mount  and  to  dismount  quickly,  but  this  involves  little  more  agility  than 
is  required  to  enter  or  to  leave  an  omnibus  while  in  motion.  Bicychng  is 
not  adapted  for  men  past  middle  life,  and  there  are  very  few  riders  who  may 
be  classed  as  old  men. 

The  exercise  is  admirable  for  all  who  require  development  in  the  lower 
■extremities  and  who  complain  of  being  'weak  in  the  loins.'  Those  who 
are  disposed  to  phthisis  or  who  desire  to  develop  their  lung  capacity  should 
take  up  some  other  exercise  than  bicycling.  It  is  not  perhaps  quite  the 
exercise  for  the  timid  and  nervous,  and  it  should  not  be  adopted  by  the 
subjects  of  urethral  or  prostatic  disease,  of  hernia,  of  varicose  veins,  or  of 
varicocele. 

The  exercise  appears  to  have  a  very  beneficial  effect  in  reheving  chronic 
constipation,  and  is  adopted  with  advantage  by  those  who  are  the  subjects 
of  dyspepsia,  haemorrhoids,  and  functional  disorders  of  the  liver. 

As  in  other  forms  of  exercise,  racing  and  the  breaking  of  records  should 
be  left  to  the  young,  well-trained,  strong,  and  athletic,  and  the  acquiring  of 
tricks  in  riding  to  the  acrobat,  who  has  to  live  by  his  eccentricities.  The 
ordinary  rider  when  touring  should  satisfy  himself  with  a  pace  of  not  more 
than  ten  miles  an  hour,  and  a  distance  not  exceeding  fifty  miles  in  the  day. 


592  HYGIENE 

The  bicyclist  should  be  well  equipped,  should  Avear  well-cut  or,  better  still, 
well-woven  breeches,  should  be  clad  entirely  in  wool,  and  should  burden 
himself  with  as  Httle  luggage  as  possible.  He  should  avoid  tight-fitting  shoes, 
stiff  collars,  braided  uniforms,  gauntlets,  rubber-soled  shoes,  and  waterproof 
suits.  The  only  waterproof  worn  should  take  the  form  of  a  loose  cape.  The 
best  shoes  are  thin  leather  walking  shoes. 

Tricycling. — In  tricycling  the  muscles  of  the  lower  extremities  are  almost 
the  only  ones  involved.  No  balance  has  to  be  maintained,  and  the  steering 
is  accomplished  with  a  very  small  amount  of  muscular  exertion.  The  rider 
has  to  maintain  the  body  erect,  and  must  thus  employ  the  muscles  of  the 
trunk.  As  an  exercise,  tricycling  is  undoubtedly  inferior  to  bicycling.  The 
machine  is,  moreover,  comparatively  large  and  cumbrous,  and  in  a  small 
London  house  is  perhaps  with  difficulty  disposed  of.  It  cannot  be  so  well 
conveyed  from  place  to  place,  and  when  on  a  tour  the  rider  must  always 
seek  a  shelter  for  his  machine.  The  small  size  of  the  bicycle  and  the 
convenient  manner  in  which  it  can  be  disposed  of  are  among  its  greatest 
advantages. 

The  tricycle  rider  must  keep  to  main  or  principal  roads.  The  bicyclist 
can  take  advantage  of  a  footpath.  The  machine  makes  three  tracks,  and 
upon  an  xmeven  or  frozen  road  with  sharp  ruts  the  tricycle  has  very  decided 
disadvantages  over  the  bicycle. 

While  in  touring  the  bicyclist  can  make  ten  miles  an  hour,  the  tricycle 
rider  "udll  have  to  content  himself  with  eight.  On  the  other  hand,  the  advan- 
tages of  the  tricycle  are  the  following.  The  machine  is  very  easy  to  ride, 
and  can  be  ridden  at  once  and  without  any  teaching.  No  balancing  is  re- 
quired. The  machine  can  be  driven  with  less  muscular  exertion,  and  by 
altering  the  gearing  a  machine  can  be  adapted  to  almost  every  grade  of 
muscular  capacity.  The  tricycle  can  be  ridden  by  the  old,  the  nervous,  the 
moderately  feeble,  the  lame.  It  can  be  ridden  by  ladies  and  young  girls. 
At  the  same  time,  with  an  athletic  rider  a  great  speed  can  be  attained  on  the 
machine  and  enormous  distances  covered. 

Three  great  and  very  decided  advantages  of  the  tricycle  are  these :  the 
rider  can  stop  the  machine,  and  can  rest  and  enjoy  the  scenery,  without  dis- 
mounting ;  he  can  ride  without  taking  very  minute  note  of  the  road  ;  he  can 
carry  a  considerable  quantity  of  luggage. 

Tricychng  is  a  most  admirable  exercise  for  those  past  middle  life.  They 
can  take  their  exercise  without  fear  and  without  trouble,  and  can  moderate 
then-  exertions  to  any  degree.  It  can  be  made  a  violent  exercise  or  a  very 
gentle  one.  It  throws  no  great  strain  upon  the  heart  or  limgs.  It  appears 
to  have  a  good  effect  upon  dyspeptics  and  the  subjects  of  chronic  constipa- 
tion. It  can  be  indulged  in  within  limits  by  the  subjects  of  hernia.  It  in- 
volves all  the  advantages  attendmg  exercise  in  the  open. 

Cycling  for  Ladies  and  Girls 

Tricycling  is  extensively  and  enthusiastically  adopted  by  many  ladies 
and  young  girls.  Many  have  attained  considerable  proficiency  at  the  sport. 
The  luxury  of  a  tandem  ride  appears  to  be  keenly  appreciated  :  the  freedom 
the  lady  tricyclist  enjoys,  and  the  wide  tracks  of  coimtry  she  can  cover  in 
company  with  her  brother,  husband,  or  other  friend  are  strong  attractions  for 
the  vigorously  inclined. 

It  is  doubtful  if  tricychng  can  be  declared  to  be  a  good  or  suitable 
exercise  for  yoimg  women  and  young  girls. 

It  is  not  a  severe  exercise,  it  is  true  ;  and,  indeed,  the  amount  of  muscular 


PHYSICAL  EDUCATION  593 

exertion  demanded  can  be  very  precisely  regulated.  Many  ladies  are  em- 
phatic in  their  advocacy  of  the  claims  of  tricycling  to  be  considered  a  very 
suitable,  very  beneficial,  and  quite  harmless  exercise  for  females. 

It  must  be  remembered,  however,  that  what  applies  to  one  woman  may  not 
apply  to  another,  and  that  arguments  applicable  to  the  middle-aged  may  not 
be  equally  suited  to  the  young. 

The  precise  evidence  which  is  required  to  decide  the  question  of  the 
value  of  tricycling  for  women  and  girls  is  a  little  difficult  to  obtain  and  to 
formulate. 

These  points  may  be  drawn  attention  to. 

It  is  a  question  whether  an  exercise  involving  extensive  use  of  the  lower 
limbs  and  of  the  muscles  about  the  pelvis  is  an  unmixed  good  during  the 
years  of  active  uterine  life. 

During  the  menstrual  period  it  may  be  assumed  that  the  exercise  would, 
for  many  reasons,  be  regarded  as  most  undesirable  ;  and  there  may  possibly 
be  some  truth  in  the  loose  assertion  that  menstrual  irregularities  have  been 
developed  by  tricycling.  There  is  a  real  difficulty  in  the  matter  of  the 
saddle.  The  modern  ladies'  saddle  is  a  great  improvement  upon  the  older 
pattern,  but  the  writer  knows  of  no  saddle  which  can  be  assumed  to  entirely 
do  away  with  the  possibility  of  pressure  upon  the  pudendum. 

Individuals  have  complained  of  much  chafing  in  the  pudendal  region 
as  a  result  of  riding,  and,  without  entering  into  further  details,  the  question 
may  be  asked  whether  in  young  girls  or  in  young  women  an  exercise  is  good 
which  may  involve  considerable  pressure  and  friction  in  the  pudendal  region. 
The  very  detailed  objections  which  have  been  allowed  to  apply  to  the  use  of 
treadle  sewing  m.achines  by  factory  girls  would  appear  to  apply  to  the  riding 
of  a  tricycle. 

My  personal  opinion  would  take  the  form  of  suggesting  that  there  are 
better  exercises  for  the  gentler  sex  than  tricycling  provides,  that  the  exercise 
should  not  be  undertaken  by  young  girls  and  young  women,  but  that  it  may 
be  open  to  those  who  are  married  or  middle-aged.  I  am  aware  of  one  or  two 
instances  in  which  ladies  have  abandoned  tricycling  after  a  few  months'  en 
thusiastic  pursuit  of  the  exercise  without  affording  a  more  definite  excuse 
than  that  'it  did  not  agree  with  them.'  That  tricycling  is  not  the  exercise 
best  suited  for  a  girl  about  puberty  or  a  yoixng  immarried  woman  I  am 
convinced,  and  one  cannot  help  noticing  that  the  most  enthusiastic,  most 
successful,  and  most  persistent  lady  riders  are  no  longer  young. 

Bicycle  riding  for  ladies  and  girls  may  be  condemned  for  the  same  reasons 
which  have  been  mentioned  in  connection  with  tricycling.  Very  ingenious 
Safety  Bicycles  for  ladies  have  been  designed,  but  it  is  evident  that— with  the 
present  shape  of  saddle  at  least — they  cannot  be  ridden  without  producing 
pressure  and  friction  in  the  pudendal  region.  The  mounting  and  dismount- 
ing is  difficult :  although  it  can  be  performed  with  perfect  decency,  the  learn- 
ing to  ride  involves  greater  pains,  and  the  dress  distinctly  adds  to  whatever 
dangers  may  attend  the  machine. 

There  are  many  very  admirable,  harmless,  and  delightful  exercises  open 
to  the  tender  sex,  but  among  these  cychng,  and  more  especially  bicyclmg, 
need  not  be  included. 

Gymnastics  and  Calisthenics 

These  terms  have  been,  and  are,  employed  in  so  many  senses  that  they 
scarcely  admit  of  any  precise  definition,  and  certainly  of  no  definition  w^hicb 
would  meet  with  general  acceptance. 

VOL.  I.  Q  Q 


594  HYGIENE 

The  terra  'gymnastics'  is  usually  considered  to  ap^ly  to  a  series  of  exercises 
of  a  somewhat  severe  or  advanced  character,  and  especially  to  such  as  involve 
the  use  of  apparatus.  The  term  '  calisthenics  '  is  usually  associated  with  a 
milder  form  of  systematic  exercises,  with  '  free  movements,'  with  exercises 
which  involve  no  apparatus,  with  the  simpler  forms  of  drilling,  and  the  like. 
The  definitions  of  the  words  given  in  the  '  Century  Dictionary  '  are  convenient 
ones.  '  Calisthenics  :  The  art  or  practice  of  exercising  the  muscles  for  the 
purpose  of  gaining  health,  strength,  or  grace  of  form  and  movement ;  a  kind 
of  light  gymnastics.'    '  Gymnastics  :  The  art  of  performing  athletic  exercises.' 

The  first  expression  which  presents  itself  in  the  consideration  of  gym- 
nastic exercises  or  the  teaching  of  calisthenics  is  the  unfortunate  term 
*  system.'  The  question  asked  of  any  mstructor  is  '  what  system  does  he 
teach  ?  '  and  of  any  scheme  of  exercises,  '  what  system  does  it  follow  ?  *  Con- 
siderable discussions  have  ensued  upon  the  question  as  to  which  system  of 
gymnastics  is  the  best ;  and  while  at  one  centre  of  physical  education  faith  is 
fixed  upon  one  system,  an  opposite  belief  holds  sway  at  another. 

When  the  details  of  opposed  systems  are  considered,  and  the  claims  of 
rival  schools  are  weighed,  no  little  confusion  arises.  The  impartial  observer 
feels  that  he  must  seek  for  some  great  fundamental  characteristics  whereby 
to  separate  one  method  from  another.  He  finds  that  original  systems  have 
been  modified,  reconstructed,  added  to,  and  even  blended  with  methods 
from  other  sources.  He  observes  that  the  conception  one  instructor  of 
gymnastics  has  formed  of  a  system  of  training  difi'ers  materially  from  the 
interpretation  another  teacher  has  adopted  of  the  very  same  system.  Several 
of  the  more  modern  works  upon  gymnastics  form  a  mere  olla  podrida,  a 
mixture  of  this  system  and  of  that,  with  modifications  introduced  by  the 
author  and  such  emendations  as  obscure  all  means  of  classification. 

I  have  myself  witnessed  a  '  display  '  advertised  as  a  demonstration  of  the 
Swedish  system  of  gymnastics,  in  which  musical  drill,  the  use  of  bar-bells 
and  dumb-bells,  were  the  main  features,  and  in  which  none  of  the  familiar 
characteristics  of  the  Swedish  system  were  notable. 

As  a  matter  of  fact,  the  terms  '  Swedish  system,'  '  Swedish  gymnastics,' 
and  '  Ling's  method '  are  used  in  so  indiscriminate  a  manner,  that  the 
expressions  have  in  the  mouths  of  many  become  to  be  synonymous  with  any 
form  of  free  movements  or  any  species  of  gymnastic  training  which  is  not 
violent  or  which  does  not  involve  fixed  apparatus. 

One  soon  has  to  conclude  that  no  one  system  is  ^;cr  sc  complete  and  all- 
sufficient,  that  no  one  can  lay  claim  to  international  adoption,  that  evil  may 
result  from  a  blind  adhesion  to  one  particular  method,  and  that  considerable 
allowance  has  to  be  made  for  nationality,  physical  condition,  and  physical  tastes. 

While  this  is  true  it  must  also  be  allowed  that  if  a  certain  system  be 
advocated  and  professed  it  should  be  maintained  in  its  entirety  so  long  as 
its  distinctive  title  is  adhered  to  and  employed. 

So  far  as  the  present  purpose  of  this  article  is  concerned,  it  may  be  said 
that  there  are  three  methods  of  gymnastic  exercise  which  for  purposes  of 
convenience  may  be  here  set  forth.  It  must  not  for  a  moment  be  supposed 
that  such  a  classification  is  in  any  way  complete,  nor  is  it  historically  precise, 
nor  perhaps  even  just.  The  systems  alluded  to  are — 1,  the  English  ;  2,  the 
German  ;  and  3,  the  Swedish. 

1.  By  the  English  system  is  understood  a  method  of  physical  training 
by  means  of  athletic  exercises  and  outdoor  sports.  This  system  is  considered 
to  include  marching,  running,  both  long  distance  runnmg  and  sprint  running, 
leaping,  swimming,  &c.,  trials  of  strength  and  endurance,  and  the  usual  out- 
door sports,  such  as  cricket,  football,  and  rowing. 


PHYSICAL  EDUCATION  595 

This  is  the  sense  in  which  most  foreign  writers  describe  the  Enghsh 
system.  The  definition  is  not  very  liberal,  but  it  is  very  convenient.  It  is 
true  of  physical  training  in  England  many  years  ago,  but  of  course  does  not 
profess  to  represent  such  training  as  is  at  present  carried  out. 

It  is  needless  to  criticise  what  is  termed  the  English  system.  The  value 
of  athletic  sports  and  outdoor  games  is  recognised  and  is  appreciated  in  no 
country  so  keenly  as  in  England. 

As  a  method  of  training,  it  is  obviously  crude,  unscientific,  incomplete, 
and  of  restricted  application.  It  is  a  pleasant  training  for  lusty  boys  and 
vigorous  men,  but  it  is  perfectly  clear  that  it  can  lay  no  claim  to  be  con- 
sidered as  a  precise  and  orthodox  system. 

2.  The  German  system  may  be  spoken  of  as  being  assimilative.  The 
German  writers  and  teachers  have  adopted  and  embodied  whatever  they 
found  good  in  the  practices  of  other  peoples  in  the  matter  of  physical  educa- 
tion. No  system  is  more  liberal,  more  extensive,  more  catholic.  As  Mr. 
Metzner  well  says  in  his  account  of  the  German  system  of  gymnastics 
(Physical  Training  Conference,  Boston,  1889),  'the  German  system  does 
not  claim  to  have  any  special  exercise  of  its  own,  or  to  be  the  sole  proprietor 
oi  any  that  no  other  system  may  also  produce.'  The  system  has  been  slowly 
built  up  during  nearly  a  century,  and  has  shown  as  a  main  characteristic 
the  power  of  intelligent  assimilation  and  the  ready  appreciation  and  develop- 
ment of  what  has  appeared  good  in  physical  training. 

The  German  system  embraces  all  the  different  branches  of  gymnastics, 
ifree  movements,  mass  exercises  in  every  form,  with  wands,  dumb-bells,  flags, 
bar-bells,  &c.,  figure  marchmg,  trot  marching,  the  use  of  a  most  varied  and 
extensive  series  of  fixed  apparatus,  the  use  of  clubs  and  all  forms  of  hand 
apparatus,  and  the  encouragement  of  such  exercises  as  come  under  the 
heading  of  outdoor  sports. 

It  aims  at  general  physical  culture  and  does  not  encourage  the  develop- 
ment of  especial  powers  or  especial  abilities  ;  it  encourages  exercises  in 
classes  (mass  exercises)  and  endeavours  to  infuse  interest  and  amusement  in 
its  instructions  ;  it  aims  at  being  complete  and  of  being  capable  of  adaptation 
by  individuals  of  all  ages  and  of  very  varied  physical  ability ;  it  encourages 
a  gradual  and  progressive  form  of  instruction,  the  pupil  commencing  with  the 
simplest  exercises  and  proceeding  with  the  more  difficult  and  arduous  only 
when  the  more  rudimentary  have  been  fully  mastered. 

A  description  of  the  exercises  carried  out  under  the  German  system 
would  require  a  treatise  of  considerable  length,  (a)  The  free  exercises  imply 
various  movements  of  the  hmbs  and  trunk  carried  out  without  apparatus. 
They  include  manifold  movements  of  the  arms  and  legs,  bending  and  rotating 
of  the  body  in  various  directions,  and  the  assuming  of  a  number  of  attitudes 
and  postures. 

By  these  free  movements  it  is  considered  that  every  muscle  is  exercised ; 
the  exercises  are  simple,  gentle,  and  are  especially  adapted  for  children, 
although  they  should  form  the  preliminary  course  in  any  scheme  of  physical 
training.  They  are  repeated  a  great  number  of  times  and  are  effected 
symmetrically  so  that  each  side  of  the  body  may  be  equally  developed.  They 
are  so  arranged  as  to  be  progressive,  and  every  attempt  should  be  made  to 
render  them  complete.  These  exercises  are  obviously  best  conducted  in  classes, 
and  many  are  very  conveniently  carried  out  to  music,  as  the  German  system 
allows.  They  are  popular  and  interesting.  They  tend  not  only  to  develop 
the  muscles  but  also  to  quicken  attention,  to  encourage  rapid,  precise,  and 
well  co-ordinated  movements,  and  to  bring  about  the  mental  alertness  and 
the  physical  smartness  which  are  elicited  by  any  well-conducted  drill.     They 

QQ2 


596  HYGIENE 

tend  to  give  grace  and  ease  and  freedom  to  the  movements  and  to  favom'  a 
good  carriage. 

No  system  of  physical  education  is  complete  which  is  not  founded  upon 
a  sound  grounding  in  free  exercises. 

It  is  only  fair  to  state  that  some  of  the  best  of  the  free  movements 
carried  out  in  the  German  system  have  been  derived  from  the  Swedish 
schools.  The  exercises  are  perhaps,  on  the  w^hole,  more  interesting  and  more 
pictm'esque  than  those  adopted  by  the  Swedish  system.  They  are,  however, 
less  precise  and  less  complete  and  less  elaborately  systematised  as  a  part  of  a 
progressive  system  of  education.  Not  a  few  of  these  German  free  exercises 
have  little  educational  purpose,  and  appear  to  be  adopted  more  for  effect  and 
to  meet  the  requirements  of  a  public  display.  Some  recent  modifications  and 
additions  have  little  claim  to  serious  attention,  and  do  not  elicit  the  best 
possible  employment  of  the  pupil's  time.  Compared  wdth  the  Swedish 
exercises,  however,  they  are,  on  the  whole,  more  popular  with  children,  and 
are  certainly  more  picturesque. 

(6)  Another  series  of  exercises  involve  the  use  of  very  light  liand  ajyj^aratus, 
such  as  bar-bells,  wooden  dumb-bells,  flags,  hoops,  &c.  These  exercises, 
although  they  concern  to  a  great  extent  the  upper  part  of  the  trunk  and  the 
upper  limbs,  involve  also  the  development  of  the  other  muscles  of  the  body. 
The  weight  of  the  apparatus  used  is  but  a  slight  element  in  the  exercises, 
which  are  nearly  of  the  same  character  as  those  just  described.  The 
apparatus  gives  precision  to  the  movements,  makes  the  exercises  more  inter- 
esting and  more  easily  carried  out,  and  renders  the  instructor's  work  some- 
what less  difficult.  These  exercises  are  adapted  for  elder  children  and  form 
a  peculiarly  valuable  element  in  education.  They  represent  an  advancement 
upon  the  free  movements,  and  in  a  systematic  and  progressive  plan  of 
instruction  would  naturally  follow  upon  those  exercises.  These  exercises 
with  apparatus  may  also  be  carried  out  to  music. 

(c)  Although  drilling  does  not  form  a  very  conspicuous  element  in  the 
German  system,  the  subject  may  be  conveniently  introduced  here,  especially 
as  the  modern  gymnastic  drill  is  largely  a  German  production.  A  certain 
amount  of  drilling  is  of  value,  and  forms  an  efficient  means  of  cultivating  a 
good  carriage  and  an  easy  and  free  mode  of  walking  and  marching.  Military 
drill  is  a  little  tedious  and  formal  and,  to  a  considerable  extent,  purposeless, 
so  far  as  a  full  physical  education  is  concerned.  It  tends  to  sharpen  the 
wits  of  dull  lads  and  to  encourage  precise  and  active  movements.  It  is, 
however,  uninteresting  to  the  pupil,  and  does  not  afford  in  any  way  a  com- 
plete or  satisfactory  method  of  employmg  the  muscles.  In  the  physical 
training  of  cliildren  it  may  well  be  replaced  by  more  valuable  exercises. 

The  musical  drill  of  more  modern  times  is  very  different  from  the  drill- 
sergeant's  work.  Musical  drill  appears  to  have  been  introduced  from 
America,  and  it  now  forms  a  conspicuous  feature  in  most  training  schools. 
It  consists  of  marching  or  running  in  such  a  manner  as  to  describe  a  variety 
of  figures,  and  always  to  music. 

Under  this  heading  come  the  many  forms  of  the  musical  running  or 
marching  maze,  which  include  marching  in  two  or  four  circles,  or  in  reverse 
circles,  or  in  parallel  lines,  or  in  what  is  known  as  the  serpentine  course. 
This  drill  is  only  possible  with  a  comparatively  large  class.  It  is  very 
popular  with  children  and  with  lads  and  elder  girls.  It  forms  an  excellent 
relaxation  from  the  more  formal  exercises  and  represents  running  with  a 
purpose.  Many  admirable  books  have  appeared  on  the  subject.  The  three 
forms  of  exercise  just  described  are  especially  well  adapted  for  children  and 
for  instruction  in  schools.  They  serve  to  form  the  basis  of  a  very  sound  and 
perfect  physical  drill. 


PHYSICAL  EDUCATION  597 

If  the  work  of  a  school  could  be  interrupted  for  thirty  minutes  in  the 
middle  of  the  morning  in  order  that  the  children  might  go  through  some 
few  dumb-bell  or  bar-bell  exercises  in  fresher  air,  and  then  finish  up  with 
the  running  maze  to  music,  something  would  be  done  towards  securing  a 
reasonable  development  of  the  body.  All  that  is  required  is  a  competent 
teacher,  plenty  of  floor  or  ground  space,  some  very  simple  apparatus,  and 
equally  simple  music. 

(d)  The  use  of  gymnastic  apioaratus  is  considered  in  a  subsequent  section. 
In  the  employment  of  apparatus  and  in  the  invention  and  elaboration  of 
gymnastic  appliances  of  various  kinds  the  German  schools  have  been  very 
active.  Indeed,  the  use  of  apparatus  is  so  prominent  in  the  system  that  it 
has  been  often  improperly  considered  to  represent  its  principal  feature. 

8.  The  Swedish  system,  or  the  system  introduced  by.  Ling,  has  attracted 
very  considerable  attention,  and  has  certainly  been  the  m'eans  of  effecting  not 
only  a  remarkable  improvement  in  physical  education,  but  a  change  which 
may  be  spoken  of  as  little  less  than  a  revolution.  It  may  be  that  the  whole 
method  is  not  original,  and  that  some  of  its  features  have  been  anticipated, 
but  as  a  system  it  has  been  enthusiastically  accepted,  and  certainly  met  a 
want  which  had  been  felt  in  physical  education. 

There  was  a  time  in  this  country  when  in  the  matter  of  physical  educa- 
tion there  was  little  between  somewhat  violent  outdoor  sports  and  certain 
acrobatic  feats  in  the  gymnasium  on  the  one  hand  and  the  dreary  instruc- 
tion of  the  drill-sergeant  on  the  other.  The  young  girls  of  that  period  had 
also,  it  must  be  allowed,  the  services  of  the  so-called  professor  of  deport- 
ment, but  of  the  value  of  his  instruction  it  is  difficult  to  speak.  Physical 
training  in  those  days  was  for  the  strong.  It  encouraged  specialisation  ;  it 
did  not  concern  itself  with  a  systematic  and  progressive  development  of  the 
human  body. 

The  Swedish  system  of  physical  training  includes  a  very  extensive  series 
of  free  movements,  a  series  of  exercises  involving  marching,  leaping,  running 
and  climbing,  and  certain  carefully  graduated  exercises  on  the  boom,  rib- 
stool,  and  window  ladder.  The  free  movements  are  admirable,  and  for  them 
these  advantages  can  be  claimed.  They  have  been  carefully  worked  out : 
each  series  of  movements  are  definite  and  precise,  and  are  intended  to 
develop  a  special  series  of  muscles ;  the  exercises  are  systematic  and  pro- 
gressive, and  form  in  their  entirety  a  complete  and  simple  system  of  physical 
training. 

The  movements  are  not  designed  with  a  view  to  effect  or  display,  but 
simply  to  carry  out  the  scheme  of  muscular  training.  They  are  designed 
with  care,  and  each  accomplishes  a  specific  object.  The  exercises  begin  with 
the  very  simplest  and  gradually  become  stronger  and  more  complicated. 

The  use  of  hand  apparatus  is  only  sanctioned  after  a  complete  mastery  of 
the  free  movements  have  been  attained,  and  then  only  to  add  some  intensity 
to  those  movements. 

The  fixed  apparatus  mostly  employed  by  teachers  of  the  Swedish  system 
are  the  boom,  the  rib-stool,  and  the  window  ladder.  The  latter  forms  an  ex- 
cellent exercise  for  children  and  affords  them  no  little  amusement.  The 
method  prepares  the  way  for  so-called  sesthetical  gymnastics,  for  fencing, 
military  driU,  and  other  forms  of  applied  gymnastics. 

All  the  movements  of  the  drill  are  applied  to  words  of  command,  and  the 
pupil  gains  all  those  advantages,  mental  and  otherwise,  which  attend  the 
teaching  of  exercises  by  the  drill  method,  i.e.  by  word  of  command  rather 
than  by  imitation  or  by  committing  the  movements  to  memory. 

The  Swedish  system  disapproves  utterly  of  the  use  of  music,  and  it  is 
■contended  that  the  exercises  cannot  be  adopted  to  one  set  rliythm. 


598  HYGIENE 

Against  the  Swedish  method  it  may  be  m-ged  that  the  exercises  are  a 
little  uninteresting  to  the  pupils,  that  many  of  them  appear  ungainly  and 
purposeless,  and  that  the  great  advantage  of  a  musical  acconipaniniGntis  lost. 

The  chief  movements  may  be  classed  under  the  following  divisions  : 

(a)  Fundamental  positions. — These  are  intended  to  secure  general  atten- 
tion and  muscular  control,  and  to  establish  the  equilibrium  and  base  of 
support  before  more  difficult  exercises  are  undertaken. 

(b)  Arch  flexions  comprise  various  forms  of  backward  flexions  of  the 
trunk,  and  are  intended  to  develop  the  dorsal  muscles  and  those  of  the 
abdomen,  and,  to  expand  the  lower  part  of  the  chest. 

(c)  Heaving  movements. — These  comprise  forms  of  self-suspension  by 
means  of  the  arms  on  a  horizontal  bar  or  other  apparatus,  and  serve  to 
expand  the  chest  and  to  strengthen  the  muscles  of  the  upper  limb. 

{d)  Balance  movements. — The  positions  are  taken  from  a  smaller  area 
than  that  included  within  the  feet  in  standing  ;  the  difficulty  is  increased  by 
diminution  of  the  area  of  support.  The  exercises  develop  the  equipoise  of 
the  body  and  give  grace  to  the  carriage. 

(e)  Shoiolder-blade  movements  are  concerned  mainly  with  the  scapular 
muscles. 

(/)  Abdominal  movements  call  into  special  action  the  muscles  of  the 
abdomen. 

[g)  Lateral  trunk  movements.- — These  include  various  forms  of  lateral 
flexion  of  the  body,  and  of  rotatory  movements,  and  concern  generally  the 
muscles  of  the  trunk. 

(/i)  Slow  leg  movements. — They  are  to  specially  develop  the  individual 
muscles  of  the  leg. 

{i)  Jumping  and  vaulting,  and  (j)  respiratory  exercises  call  for  no- 
explanation. 

In  the  article  on 'Physical  Development,' in  Keating's  'Cyclopaedia  of 
the  Diseases  of  Children  '  (vol.  iv.  p.  303),  will  be  found  a  brief  but  lucid 
exposition  of  the  actual  details  of  the  Swedish  drill,  illustrated  by  numerous 
figures  of  the  various  positions. 

An  excellent  '  Manual  of  Swedish  Drill  '  has  been  produced  by  George 
Meho  (London,  1889).  The  reader  may  also  consult  a  'Manual  of  Free- 
standing Movements,'  by  Captain  Haasum,  of  the  Eoyal  Gymnastic  Institute, 
Stockholm  (London,  1885).  Both  books  are  admirable.  Mr.  Melio's  various 
contributions  to  our  knowledge  of  Swedish  gymnastics  have  been  very  valu- 
able, inasmuch  as  his  early  training  was  not  carried  out  under  the  Swedish 
method. 

The  Swedish  system  of  physical  training  originated  with  Ling,  and  has 
been  considerably  developed  and  extended  by  his  pupils  and  followers. 

Petter  Henrik  Ling  was  born  at  Ljunga,  in  Smaland,  in  17G6.  His  early 
hfe  appears  to  have  been  absorbed  by  a  struggle  against  poverty,  and  he 
passed  through  many  vicissitudes.  He  seems  to  have  been  engaged  in  many 
pursuits  and  to  have  travelled  in  many  countries.  In  1800  he  was  studying 
gymnastics  at  Copenhagen,  and  in  1804  he  was  engaged  as  a  fencing  master 
at  Lund.  His  system  of  physical  training  was  elaborated  after  this  date. 
The  Pioyal  Gymnastic  Institute  was  founded  at  Stockholm  in  1815  at  his 
instigation,  and  remained  under  his  supervision  until  his  death  in  1839. 

Ling  figured  as  a  poet  and  a  dramatist ;  he  dabbled  with  the  flimsier  forms 
of  metaphysics  and  held  some  crude  conceptions  of  physiology.  His  educa- 
tion was  scarcely  such  as  to  fit  him  for  the  position  he  ultimately  held. 

Ling  held  that  life  consisted  of  the  blending  together  of  three  elements — 
the  dynamic,  the  chemical,  and  the  mechanical — and  upon  this  belief  his 


PHYSICAL  EDUCATION  599 

'  system '  was  founded.  Many  of  his  exercises  were  only  suited  to  invalids, 
and  he  professed  to  have  discovered  the  means  of  curing  most  diseases  by 
physical  movements.  His  exercises  were  indeed  divided  into  scholastic,  mili- 
tary, medical,  and  aesthetic  gymnastics.  He  considered  that  every  muscular 
movement  had  a  special  effect  upon  the  general  health,  and  held  that  passive 
movements  had  a  definite  value  in  promoting  the  development  of  the  body. 

It  must  be  confessed  that  his  system  (excellent  as  some  features  of  it 
u.ndoubtedly  are)  was  founded  upon  not  a  few  extravagant  theories  and  upon 
bases  which  were  not  always  scientific  or  accurate. 

The  medical  side  of  the  system  has  been  the  means  of  fostering  a  form 
of  quackery,  and  has  led  to  the  introduction  of  the  *  remedial  exercises  ' 
and  *  movement  cures '  which  have  done  so  much  to  bring  Swedish  gym- 
nastics into  discredit  in  this  country.  Out  of  the  complex,  heterogeneous, 
and  visionary  material  which  makes  up  Ling's  system,  much  that  is  really 
good  and  valuable  has  been  extracted.  This  is  represented  by  the  excel- 
lent system  of  free  movements  already  described  and  by  many  of  the  methods 
of  treating  diseases  by  exercise  which  have  been  heartily  accepted  and  de- 
veloped by  the  medical  men  of  this  and  other  countries.  In  Anna  Arnin's 
'  Health  Maps '  (London,  1887)  and  in  Schreiber's  '  Manual  of  Treatment 
by  Massage '  (Edinburgh,  1887)  will  be  found  good  accounts  of  the  application 
of  movements  to  the  treatment  of  abnormal  and  diseased  conditions. 

In  proposing  a  course  of  '  Swedish  gymnastics  '  or  in  advocating  '  Ling's 
system '  it  is  desirable  that  a  clear  knowledge  should  be  possessed  of  what 
is  implied  by  these  terms,  and  that  encouragement  be  not  offered  to  the 
'  remedial  measures,'  the  '  movement  cures,'  and  the  quackery  with  which  this 
otherwise  excellent  system  is  attended.  Any  instructor  who  describes  himself 
as  a  '  medical  gymnast '  will  probably  not  be  sought  for  as  a  teacher. 

Ling's  system  in  its  entirety  could  hardly  be  accepted  at  the  present  day. 
Such  portion  of  the  Swedish  system  as  deals  with  the  practical  part  of 
physical  education  pure  and  simple  must,  however,  be  accepted  as  of  con- 
siderable worth. 

Gymnastic  Appaeatus 

Under  this  title  will  be  considered  the  use  of  such  apparatus  as  will  be 
found  in  a  well-equipped  gymnasium.  A  good  gymnasium  should  have 
ample  space,  good  light,  very  free  ventilation,  the  best  possible  apparatus, 
and  a  fully  quahfied  instructor. 

The  fresher  the  air  and  (within  limits)  the  cooler  the  room  the  better. 
A  properly  ventilated  gymnasium  has  an  unlimited  supply  of  fresh  air  with- 
out draughts.  If  there  be  a  time  when  plenty  of  oxygen  is  required  it  is  when 
young  persons  are  taking  violent  exercise.  Many  gymnasia  are  ill-lit, 
cramped,  and  very  badly  ventilated. 

The  majority  of  the  exercises  involved  in  the  use  of  gymnastic  apparatus 
involves  considerable  strength  and  much  practice. 

It  is  madness  for  a  man  out  of  training  and  unaccustomed  to  exercise 
to  commence  in  a  gymnasium  the  use  of  such  apparatus  as  the  horizontal 
bar  or  the  vaulting  horse.  Many  children,  especially  girls,  have  been 
seriously  damaged  by  the  violent  exertions  undertaken  in  improperly  con- 
ducted gymnasia. 

Such  gymnasia  have  done  a  very  great  deal  to  bring  physical  training  into 
discredit.  A  boy  of  about  ten  has  joined  a  '  gymnastic  class  ;  '  his  physical 
condition  has  never  been  examined  and  his  physical  capacities  never  in- 
quired into.    He  enters  the  gymnasium,  and  without  any  prehminary  training 


GOO  HYGIENE 

attempts  the  feats  he  sees  other  pupils  performing  without  perhaps  having 
received  any  definite  instruction.  The  boy  goes  home  dead-beat,  feeble,  and 
sick  at  heart  at  his  ill-success  and  aching  with  his  unwonted  exertions.  Next 
day  he  presents  all  the  phenomena  of  extreme  fatigue  and  perhaps  the  symp- 
toms of  muscular  strain.  I  have  known  more  than  one  instance  in  which 
a  hernia  made  its  appearance  after  a  first  attendance  at  a  gymnasium. 

The  very  greatest  care  should  be  exercised  in  the  management  of  all 
children  and  young  people  sent  to  a  gymnasium.  Parents  who  take  infinite 
pains  to  superAase  the  mental  education  of  their  children  often  take  not  the 
least  trouble  to  ascertain  the  conditions  under  which  their  bodies  are  being 
trained.  A  lad  comes  home  with  a  headache  and  Avith  all  the  symptoms 
of  exhaustion  from  the  hour's  drill,  and  is  not  allowed  to  attend  again  on  the 
grounds  that  he  is  not  *  strong  enough  for  rough  exercise.'  A  visit  to  the 
gymnnsium  may  have  shown  that  the  headache  was  due  to  an  ill-ventilated 
and  over- heated  room,  and  the  exhaustion  to  totally  unsuitable  exercises. 

It  must  be  remembered  that  physical  training  requires  discretion ; 
that  a  great  mass  of  pupils,  even  when  of  the  same  age  and  sex,  cannot  be  all 
dealt  with  en  masse  by  fixed  rules.  The  exercises  selected  and  the  apparatus 
to  be  used  must  be  determined,  not  by  rule  of  thumb,  but  by  the  precise  needs 
of  each  individual  case.  This  observation  will  not  apply  to  drilling  and  to 
simple  mass  exercises,  but  it  applies  in  a  very  emphatic  manner  to  apparatus. 

A  gymnasium  is  worse  than  useless  without  an  efticient  and  careful 
instructor.  Gymnastics  cannot  be  self-taught.  The  process  of  training  must 
be  gradual,  and  so  graduated  as  to  meet  the  pupil's  particular  needs  and 
particular  state  of  development. 

So-called  exercise  in  a  gymnasium  without  a  teacher  usually  means  pur- 
poseless romping.  It  may  safely  be  said  that  the  great  majority  of  the 
accidents  which  occur  in  gymnasia  occur  during  forbidden  hours  or  when  the 
pupil  is  attemptmg  exercises  by  himself  of  which  he  has  no  precise  knowledge. 

Put  an  active  boy  in  a  gymnasium  and  pay  no  attention  to  his  training, 
and  he  mil  assuredly  begin  to  '  play  the  fool,'  to  '  skylark,'  to  develop 
uncouth  modes  of  exercising  his  limbs,  and  in  the  end  very  probably  do  him- 
self more  or  less  material  damage. 

The  pupil  in  a  gymnasium  must  be  content  to  begin  at  the  beginning, 
must  learn  to  be  patient  and  to  overcome  failures,  must  be  ready  to  believe 
that  there  are  many  exercises  he  can  never  perform,  and  that  he  is  endeavour- 
ing to  acquire  health  and  strength,  and  not  to  qualify  himself  for  the  pro- 
fession of  an  acrobat.  Above  all  things,  work  in  a  gymnasium  must  be 
gradual,  regular,  and  systematic. 

A  very  lamentable  spectacle  is  that  afforded  by  a  middle-aged  man 
who  feels  he  is  becoming  stout  and  who  thinks  he  will  '  take  to  gym- 
nastics.' He  attempts  at  once  the  exercises  he  sees  his  younger  colleagues 
jjerform  with  such  complete  ease.  If  such  a  man  escapes  with  no  greater 
injury  than  is  represented  by  being  rendered  breathless,  by  having  several 
muscles  sprained,  and  by  being  laughed  at,  he  may  consider  himself  fortunate. 

In  general  terms  it  may  be  said  that  the  gymnasium  is  not  well  suited  for 
children,  is  best  suited  for  lads  and  young  men  between  the  ages  of  seventeen 
and  twenty-five,  and  is  but  indifferently  adapted  for  men  over  thirty,  unless 
they  have  kept  up  the  physical  acquirements  of  their  youth  by  constant 
practice. 

It  is  important  also  to  bear  in  mind  that  gymnastic  exercises  with 
apparatus  all  tend  to  develop  the  upper  limbs  and  the  upper  half  of  the  trunk. 

The  gymnasium  cannot  provide  the  means  for  a  complete  physical  edu- 
cation,  and  work  in  it   should  never   so   far  absorb  the  time  devoted  to 


PHYSICAL  EDUCATION  GOl 

physical  training  as  to  exclude  recreation  in  the  open  air  and  outdoor 
games  and  exercises.  Exercises  with  apparatus  come  at  the  end,  and  not  at 
the  beginning,  of  a  course  of  physical  training. 

A  very  brief  description  of  the  commoner  apparatus  will  now  be  given. 

Dumb-bells. — These  should  be  light  and  should  be  made  of  sycamore  wood. 
The  weight  for  boys  should  be  1  lb.  each  bell,  2  lb.  for  lads,  and  3  lb.  for 
adults.  Heavy  dumb-bells  are  to  be  condemned.  The  chief  feature  of  proper 
dumb-bell  exercises  is  the  great  frequency  with  which  they  are  repeated  and  the 
length  of  time  the  movements  are  kept  up.  The  weight  of  the  bell  is  not  a 
factor  of  any  moment  in  the  exercise,  but  the  apparatus  serves  to  give  interest 
and  precision  to  the  movements  carried  out.  Heavy  dumb-bells  involve 
considerable  effort  compressed  into  an  inconsiderable  time.  Such  bells  are 
only  of  use  to  athletes  who  wish  to  specially  develop  their  arms. 

Dumb-bell  exercises  are  admirable.  They  can  be  adapted  for  individuals 
of  all  ages  and  of  all  conditions  of  physical  strength  ;  they  are  well  suited 
for  class  exercises  ;  and  a  musical  drill  with  light  dumb-bells  forms  a  pleasant 
feature  in  the  training  of  boys  and  girls.  Both  bells  should  be  used  at  the 
same  time. 

The  exercises  encourage  a  good  carriage,  rapid  and  precise  movements,  and 
the  equal,  symmetrical,  and  simultaneous  use  of  the  muscles  upon  both  sides 
of  the  body. 

These  exercises  tend  to  develop  the  chest  and  to  exercise  the  muscles  of 
the  abdomen  and  back. 

It  is  true  the  arms  are  conspicuously  employed  in  dumb-bell  movements, 
but  if  the  drilling  is  efficient  nearly  all  the  muscles  of  the  body  are  well, 
although  not  equally  exercised,  and  especial  employment  can  be  given  to  the 
muscles  of  the  back. 

Bar-bells. — These  are  of  ash.  The  shaft  is  five  feet  long  (for  adults)  and 
three-quarters  of  an  inch  in  diameter.  The  knob  at  each  end  is  three  inches 
in  diameter. 

The  exercises  carried  out  with  bar-bells  resemble  those  performed  with 
dumb-bells.  They  have  especial  value  in  developing  the  muscles  of  the 
chest  and  of  the  abdomen.  The  muscles  of  the  upper  limbs  are  somewhat 
unduly  exercised,  and  considerable  work  can  be  thrown  upon  the  muscles  of 
the  back.  This  apparatus  is  excellent  for  the  narrow-chested.  It  encourages 
symmetrical  movements,  a  graceful  carriage,  and  general  lissomness  of  the 
body.     Bar-bells  are  extensively  used  in  the  training  of  young  girls. 

By  the  use  of  double  bar-bells  a  still  more  extensive  use  of  the  general 
muscular  system  is  involved.  In  these  exercises  two  bar-bells  are  held  at 
either  end  by  two  pupils ;  in  all  movements  the  two  pupils  must  act  in 
concert.  The  exercises  concern  the  whole  of  the  muscles  and  afford  ex- 
cellent training  in  symmetrical,  rapid,  and  precise  movements. 

Indian  Clubs  are  made  of  pine  wood,  and  are  about  24  in.  in  length  and 
some  3|  in.  in  diameter  at  the  thick  end.  The  exercises  are  only  suited  for 
adults  and  for  muscular  persons.  They  encourage  a  firm  and  upright  attitude, 
and  develop  principally  the  upper  part  of  the  trunk  and  the  upper  limbs. 

Many  of  the  movements  are  very  elaborate  and  require  great  nicety  of 
execution. 

Parallel  Bars  should  be  about  9  ft.  long,  20  in.  apart,  and  about  4  ft.  from 
the  ground.  Every  instructor  in  gymnastics  recognises  that  the  parallel  bars 
form  one  of  the  most  useful  apparatus  in  the  gymnasium.  '  The  exercises,' 
writes  Maclaren,  '  are  not  only  numerous  but  varied,  interesting,  and  in  them- 
selves pleasurable,  capable  of  much  artistic  effect,  and  requiring  equally 
muscular  power  and  dexterity  of  action  in  the  upper  limb.' 


602  HYGIENE 

The  usual  exercises  are  progressive  and  none  are  violent.  The  apparatus 
is  suited  for  properly  trained  pupils  of  any  age  after  twelve  or  fourteen,  and 
■within  limits  for  both  sexes,  provided  that  the  muscular  development  of  the 
learner  is  efficient.  The  exercises  improve  the  grasp,  develop  the  muscles 
of  the  upper  hmb,  and  especially  the  muscles  passing  between  the  upper 
limb  and  the  trunk.  They  are  well  adapted  for  individuals  with  slight  arms, 
wuth  narrow  and  sloping  shoulders,  and  with  contracted  chests.  Excessive 
use  of  the  bars  tends,  however,  to  develop  to  excess  the  posterior  scapular 
muscles.  The  muscles  of  the  abdomen  are  employed,  but  comparatively 
little  use  is  made  of  the  lower  extremities. 

The  Horizontal  Bar  is  about  six  feet  long,  has  a  diameter  of  1|  in.,  and 
is  raised  from  three  to  seven  feet  from  the  ground.  This  valuable  apparatus 
is  adapted  for  pupils  of  almost  any  age  above  ten  or  twelve.  The  exercises 
are  varied  and  progressive,  and  can  be  made  to  suit  various  degrees  of  mus- 
cular development. 

The  simpler  exercises  develop  the  muscles  of  the  upper  limbs  and  of  the 
upper  part  of  the  trunk  ;  the  more  advanced  call  into  play  the  muscles  of  the 
back  and  of  the  abdomen  and  to  a  less  extent  the  muscles  of  the  lower  limbs. 
The  apparatus  if  used  to  too  great  an  extent  tends  to  develop  the  upper  limb 
muscles  to  a  disproportionate  extent. 

The  simpler  exercises  are  adapted  under  careful  restriction  for  girls 
with  weak  spines,  and  for  those  with  small  scapular  muscles  and  slender 
shoulders. 

The  more  elaborate  exercises  require  considerable  strength  and  agihty, 
and  are  only  suited  for  the  athletic  and  very  muscular. 

In  certain  of  the  primary  exercises  the  abdominal  muscles  are  especially 
employed. 

The  Trapeze  is  made  of  hickory  or  ash,  is  about  20  in.  in  length  and 
some  I  in.  in  diameter.  The  height  at  which  it  is  suspended  from  the 
ground,  and  the  length  of  the  ropes,  must  depend  upon  the  capacity  and  age- 
of  the  learner. 

The  exercises  are  very  similar  to  those  of  the  horizontal  bar,  but  as  the 
pupil  can  swing  at  the  time  of  practising  this  apparatus  is  very  popular. 

It  mainly  brings  into  play  the  muscles  of  the  upper  limbs  and  those  pass- 
ing between  the  trunk  and  that  member.  It  is  of  service  in  cases  of  feeble 
back  and  commencing  lateral  curvature,  and  can  be  made  admirable  use  of 
in  developing  especially  the  muscles  of  the  abdomen. 

A  mattress  must  always  be  placed  beneath  the  low  trapeze  and  a  net 
beneath  the  higher  apparatus.  Great  care  must  be  taken  in  carrying  out 
the  movements,  and  this  apparatus  has  been  the  cause  of  not  a  few  acci- 
dents. The  more  elaborate  movements  are  only  adapted  for  the  practised 
athlete,  and  some  of  the  finest  displays  of  gymnastic  skill  are  made  with  the 
trapeze. 

The  Hand  Rings  have  a  diameter  of  from  5  to  9  in.,  are  placed  about 
18  in.  apart  when  used  by  adults,  and  at  a  distance  of  3  to  6  ft.  from  the 
floor.  This  apparatus  is  also  very  popular.  The  exercises  closely  resemble 
those  carried  out  upon  the  trapeze.  The  same  sets  of  muscles  are  concerned. 
The  apparatus,  if  properly  employed,  is  excellent  for  cases  of  lateral  cur- 
vature ;  the  lateral  muscles  of  the  trunk  can  be  very  fully  and  efficiently 
exercised,  and  one  side  can  be  especially  developed  if  required. 

The  more  elaborate  exercises  concern  the  muscles  of  the  back  and 
abdomen,  and  indeed  the  whole  muscular  system  with  the  exception  that  the 
lower  limbs  are  but  little  involved. 

Unless  care  be  exercised  it  is  easy  for  young  pupils  to  produce  an  unsym- 


PHYSICAL  EDUCATION  60a 

metrical  development  of  the   back   muscles  by  an  improper   use   of  this 
appliance. 

The  Vaulting  Horse  is  a  valuable  apparatus.  The  body  should  be  from 
5  to  6  ft.  in  length  and  should  be  capable  of  being  adjusted  at  any  height. 
Mattresses  must  be  placed  around  it,  and  a  sloping  board  is  generally  placed 
in  front  of  it  for  lea^ping  exercises. 

The  vaulting  horse  is  well  suited  for  children  and  the  young  and  for 
athletic  adults.  It  is  scarcely  the  apparatus  for  the  middle-aged.  It  may  be 
used  by  girls  under  puberty,  but  its  use  in  older  females  is  open  to  some 
question  (see  page  593). 

The  exercises  are  varied,  are  pleasurable,  and  are  popular  with  young 
people.  It  is  well  suited  for  class  instruction.  The  simpler  exercises  consist 
of  vaulting  over  the  horse  in  different  ways.  The  exercises  develop  all  the 
muscles  of  the  body,  the  lower  limbs  as  well  as  the  upper,  the  spine  as  well 
as  the  abdomen.  Its  use  brings  about  a  good  grasp,  a  certain  amount  of 
agility  and  precision  of  movement,  and  cultivates  a  good  swing  of  the  body. 
It  forms  an  excellent  means  of  cultivating  the  respiratory  apparatus  and 
brings  out  the  muscles  about  the  pelvis. 

One  of  the  most  popular  lessons  in  a  gymnasium  is  represented  by  a  class 
of  pupils  who  form  in  line  and  vault  over  the  horse  one  after  the  other,  keep- 
ing up  a  continued  round  and  run. 

The  more  advanced  exercises  are  only  suited  for  athletes  and  are  elaborate 
and  difficult.  No  gymnasium  can  be  considered  to  be  complete  without  some 
form  of  vaulting  horse. 

The  Inclined  Ladder  as  usually  employed  exercises  mainly  the  muscles 
of  the  upper  limb  and  upper  part  of  the  trunk.  The  exercises,  like  all  other 
suspension  exercises,  are  excellent  for  cases  of  weak  back  with  tendency  to 
curvature  of  the  spine  provided  that  they  are  carefully  planned  and  super- 
vised. 

The  apparatus  affords  good  practice  in  balancing  the  body  in  the  exercise 
of  mounting  the  ladder  with  the  feet  only  and  is  useful  for  developing  the 
abdominal  muscles.  It  is  suited  for  pupils  of  various  ages  and  of  both  sexes 
with  certain  limits. 

The  Ladder  Plank  is  another  useful  and  popular  apparatus.  The  machine 
is  made  in  many  different  ways.  For  adults  the  plank  is  about  18  in.  wide, 
and  from  either  side  of  it  project  spars  which  are  6  in.  in  length  and  9  in. 
apart. 

The  exercises  on  this  machine  can  be  adapted  to  individuals  of  all  ages, 
of  both  sexes,  and  of  all  degrees  of  muscular  development. 

The  muscles  of  the  entire  body  are  exercised,  although  those  of  the  upper 
limbs  and  of  the  upper  part  of  the  trunk  receive  most  employment.  Maclaren 
thinks  that  no  machine  in  the  gymnasium  so  rapidly  and  powerfully  aids  in 
the  expansion  and  development  of  the  upper  part  of  the  trunk  as  does  the 
ladder  plank. 

This  is  a  good  form  of  apparatus  for  cases  of  lateral  curvature  of  the  spine ; 
especially  good  are  the  exercises  which  involve  the  descending  of  the  plank 
backwards,  i.e.  with  the  back  to  the  plank.  These  exercises  also  throw  the 
chest  out  to  its  utmost,  and  the  apparatus  is  useful  for  the  narrow-chested 
or  pigeon-breasted.     It  is  a  valuable  apparatus  for  growing  girls  and  is 


The  Horizontal  Ladder  gives  opportunity  for  a  good  series  of  suspension 
exercises,  which  concern  mainly  the  muscles  of  the  upper  limb,  but  which 
also  develop,  to  a  lesser  degree,  the  muscles  of  the  back  and  of  the  abdomen. 
This  is  another  apparatus  of  service  in  cases  of  weak  or  distorted  back. 


€04  HYGIENE 

ApparaUis  for  Climbing. — Climbing  affords  excellent  exercise,  is  very 
popi^lar  among  children,  is  suited  for  pupils  of  both  sexes  and  for  individuals 
of  almost  any  age.  It  is  not  suited  for  those  who  have  not  had  special  mus- 
cular training,  nor  for  the  corpulent,  nor  for  those  who  are  past  middle  life. 
All  climbing  exercises  may  be  considered  as  advanced  exercises. 

Climbing  may  be  effected  in  different  ways,  and  children  are  very  apt  to 
acquire  tricks  in  climbing  which  tend  to  distort  the  body  and  to  develop  it 
imequally.  The  movements  of  chmbing  must  be  carried  out  very  precisely 
and  methodically,  and  must  be  carefully  superintended  by  the  instructor. 
Girls  and  young  women  often  make  excellent  climbers.  The  exercise  con- 
cerns all  the  muscles,  but  especially  those  of  the  upper  limbs.  It  also  tends 
to  develop  the  muscles  of  the  thighs,  back,  and  abdomen.  It  is  not  a  good 
exercise  for  the  subjects  of  spinal  curvature. 

The  apparatus  used  comprises  (1)  the  vertical  pole,  a  smooth  pole  of  any 
height,  and  with  a  diameter  varying  from  two  to  three  inches ;  (2)  the 
slanting  pole,  which  involves  a  combination  of  exercises  represented  by  the 
vertical  pole  and  the  slanting  ladder.  Tliis  apparatus  is  of  value  in  develop- 
ing the  muscles  of  the  abdomen  as  well  as  those  of  the  upper  limb.  (3)  The 
turning  pole  is  hardly  suited  for  any  but  active  youths  and  trained  athletes. 
The  exercises  are  difficult,  involve  much  muscular  power,  and,  above  all,  great 
dexterity,  precision,  and  accuracy  of  movement.  The  apparatus  consists  of  a 
slanting  pole  so  adjusted  as  to  revolve  on  its  longitudinal  axis.  The  great 
difficulty  of  the  exercises  consists  in  the  maintenance  of  the  balance  on  a  pole 
which  is  not  fixed.  (4)  The  pair  of  vertical  poles  (two  parallel  poles  placed 
eighteen  inches  apart)  is  an  apparatus  only  suited  for  advanced  gymnasts. 
The  exercises  are  very  arduous  and  demand  great  strength  and  much  practice. 
They  concern  mainly  the  upper  part  of  the  trunk  and  upper  limbs.  (5)  The 
vertical  rope  varies  in  length  and  has  a  diameter  of  from  1^  to  2  inches.  The 
exercises  resemble  those  of  the  vertical  pole,  but  are  a  little  more  varied  and 
make  more  use  of  the  lower  limbs.  (6)  The  Eosary  consists  of  a  vertical  rope 
suspended  from  the  ceihng,  but  not  fixed  at  the  foot,  upon  which  are  strung 
at  intervals  of  from  ten  to  eighteen  inches  elm  heads,  four  inches  in  diameter 
and  flat  on  the  top.  This  affords  good  exercise  in  climbing  for  children — 
boys  and  girls — and  for  beginners.  It  employs  all  the  muscles — those  of 
the  abdomen  and  back  as  well  as  those  of  the  limbs — it  concerns  most  par- 
ticularly the  muscles  of  the  upper  limbs.  It  gives  exercise  to  the  muscles 
about  the  hips  and  loins,  especially  if  it  be  understood  that  the  rope  must 
always  be  kept  in  the  vertical  line.  (7)  The  mast  (which  has  a  diameter  of 
ten  to  twelve  inches)  is  only  suited  for  accomplished  athletes. 

The  Giant's  Stride.— This  apparatus  is  more  often  found  in  the  playground 
than  in  a  gymnasium,  and  is  seldom  among  the  machines  contained  in  the 
room.  It  affords  good  exercise  for  the  muscles  of  the  body,  for  the  arms,  the 
legs,  the  abdomen,  and  the  back.  The  exercise  interests  children  and  the 
apparatus  is  always  popular.  It  is  useless,  however,  if  the  exercise  be  not 
regulated,  and  if  children  be  not  individually  instructed  in  the  simple  but 
necessary  movements.  The  children,  moreover,  should  be  about  of  the  same 
size  and  if  possible  of  the  same  state  of  physical  development. 

It  is  common  to  see  children  on  the  giant's  stride  whose  movements  are 
aimless  and  useless,  who  swing  loosely  about,  and  who  either  hamper  the 
movements  of  the  children  behind  them  or  are  hampered  by  the  struggles  of 
the  performer  immediately  in  front  of  them.  An  undisciplined  crowd  of 
children  who  without  instruction,  selection,  or  arrangement  try  to  gain  en- 
joyment and  strength  from  the  giant's  stride  had  better  devote  their  energies 
to  simpler  pursuits. 


PHYSICAL  EDUCATION  G05 

Homo  Gymnasia 

The  so-called  home  gymnasium  is  usually  more  or  less  of  a  delusion  and 
a  snare.  It  is,  as  a  rule,  too  elaborate  to  be  of  practical  value,  and  too  com- 
plicated for  children's  use.  It  often  pretends  more  than  it  can  accomplish. 
A  swing,  parallel  bars,  a  knotted  rope,  and  an  inclined  ladder  form  excellent 
elements  in  a  home  gymnasium,  provided  the  children  have  been  already  well 
trained  by  means  of  simpler  exercises. 

A  good  machine  for  home  use  is  an  American  invention,  the  so-called 
'  Excelsior  '  gymnasium.  Here  the  power  of  the  performer  is  exercised 
against  weights  attached  to  ropes  passed  through  pulleys.  The  apparatus  is 
capable  of  exercising  all  the  muscles  of  the  body,  admits  of  almost  endless 
combinations,  and  can  be  graduated  to  meet  the  needs  of  a  child  or  an 
athlete.  The  rowing  exercises  on  a  sliding  seat  and  the  contrivance  for 
developing  the  muscles  of  the  back  are  in  every  way  admirable.  The 
machine  is,  moreover,  strong,  simple,  and  portable,  and  occupies  but  little 
space  in  a  room. 

The  appliances  which  owe  their  main  features  to  elastic  bands  are  of 
limited  use,  are  restricted  chiefly  to  the  development  of  the  upper  extremities, 
and  involve  a  very  monotonous  form  of  exercise.  A  home  gymnasium  is  a 
useful  apparatus  in  a  bathroom  or  bedroom,  where  it  can  be  used  every 
morning  before  or  after  the  morning  bath. 

In  concluding  this  part  of  the  subject  attention  must  once  more  be 
directed  to  the  circumstance  that  a  inoper  and  complete  physical  education 
cannot  he  carried  out  by  means  of  apparatus.  Apparatus  come  last  in  a 
progressive  system  of  physical  training,  and  must  always  be  used  with  great 
care  and  very  sparingly.  A  large  proportion  of  the  exercises  are  totally 
unsuited  for  young  subjects,  and  are  only  open  to  athletes  or  professed  gym- 
nasts. The  tendency  of  the  usual  apparatus  is  to  produce  an  unequal 
development  of  the  body,  to  develop  the  muscles  of  the  arms  and  shoulders 
and  pectoral  regions,  and  to  neglect  the  muscles  of  the  lower  part  of  the 
trunk  and  of  the  lower  limbs.  In  a  subsequent  section  attention  is  drawn  to 
the  deformity  produced  by  an  excessive  or  exclusive  use  of  the  usual  gym- 
nastic appliances. 

Outdoor  Games 

It  is  quite  impossible  to  attempt  to  give  any  account  of  the  particular 
value  each  of  the  many  outdoor  games  may  possess  in  relation  to  physical 
education. 

In  general  terms  it  may  be  said  that  when  played  in  moderation  and 
under  suitable  conditions  they  are  most  excellent.  They  involve  movement 
in  the  open  air,  very  varied  muscular  exercise,  a  considerable  amount  of 
healthy  interest  and  excitement,  and  the  cultivation  of  a  certain  degree  of 
skill  and  special  adroitness.  The  parts  that  the  great  games  of  cricket  and 
football  have  played  in  the  development  of  the  English  people  can  scarcely 
be  overrated. 

These  games  not  only  involve  healthy  exercise  and  demand  skill,  but  they 
require  readiness  of  action,  determination,  foresight,  sound  judgment,  and 
good  temper.  They  tend  to  develop  personal  courage,  self-reliance,  the 
spirit  of  honour,  and  the  impulses  of  loyalty.  They  cultivate  all  those 
qualities  which  make  a  man  manly  and  wholesome  in  mind.  If  one  wants 
to  seek  for  the  sneaks  and  cowards  in  a  school,  for  the  poor-hearted  and  un- 
wholesome-minded, search  must  be  made,  not  among  the  cricket  and  football 
teams,  but  among  the  loafers. 


GOG  HYGIENE 

Cricket  can  be  played  at  almost  any  age,  and  is  as  well  adapted  for  young 
women  as  for  young  men.  It  is  necessary  only  that  the  players  should  be 
as  nearly  equal  in  strength  as  is  possible. 

With  regard  to  the  game  of  football,  I  cannot  do  better  than  give  two 
quotations  fi'om  Mr.  Shearman's  admirable  article  in  the  Badminton  Library 
volume.  Before  doing  so  it  is  needless  to  say  that  football  as  now  played  is 
a  game  which  involves  great  skill  and  considerable  intelligence.  The  heavy 
man  who  played  '  forward '  in  days  gone  by,  and  who  could  stand  a  good 
hacking,  and  could  hack  in  turn,  is  now  no  longer  of  any  use  in  a  football 
team.  Other  things  being  equal,  the  more  intelligent  the  man,  the  better 
the  player.  In  my  opinion  there  is  no  outdoor  game  for  lads  and  young 
men  equal  to  football,  whether  it  be  the  Eugby  Union  or  the  Association 
game. 

Thus  writes  Mr.  Shearman  :  '  For  at  least  six  centuries  the  people  have 
loved  the  work  and  struggle  of  the  rude  and  manly  game,  and  kings  with  their 
edicts,  divines  with  their  sermons,  scholars  with  their  cultured  scorn,  and 
wits  with  their  ridicule  have  failed  to  keep  the  people  away  from  the  pastime 
they  enjoyed.  Cricket  may  at  times  have  excited  greater  interest  amongst 
the  leisured  classes  ;  boatraces  may  have  drawn  larger  crowds  of  spectators 
from  distant  places  ;  but  football,  which  flourished  for  centuries  before  the 
arts  of  boating  and  cricketing  were  known,  may  fairly  claim  to  be,  not  only 
the  oldest  and  the  most  characteristic,  but  the  most  essentially  popular  sport 
of  England. 

'  Football  may  be  rough,  may  be  at  times  dangerous  ;  so  is  riding  across 
country  ;  so  is  boxing  ;  so  is  wrestling.  The  very  function  and  final  cause  of 
rough  sports  is  to  work  off  the  superfluous  animal  energy  for  which  there  is 
little  vent  in  the  piping  times  of  peace.  Since  football  became  popular  with 
aU  classes,  there  have  been  less  wrenching  off  of  knockers  and  "  boxing  of 
the  watch,"  and  fewer  "  free  fights  "  in  the  streets.  Football  has  its  national 
uses  quite  apart  from  the  cheap  enjoyment  it  has  given  to  thousands.  It  may 
be  rough,  but  it  is  not  brutal. 

'  Next  as  to  the  danger.  Doubtless  there  are  accidents,  and  doubtless  men 
have  been  killed  upon  the  football  field.  But  during  a  quarter  of  a  century 
how  many  thousands  of  men  have  played,  and  have  a  score  of  these  many 
thousands  lost  their  lives  ?  Fewer  than  those  who  have  been  drowned  on  the 
river,  not  a  tithe  of  those  who  have  fallen  in  the  hunting  field,  are  the  victims 
of  football.  If  the  outcry  against  football  because  of  its  danger  could  be 
justified,  not  a  single  outdoor  sport  could  survive. 

'  For  every  one  who  may  have  been  harmed  by  football  a  thousand  have 
benefited  by  it.  Health,  endurance,  courage,  judgment,  and,  above  all,  a  sense 
of  fair  play  are  gained  upon  the  football  field.  A  footballer  must  learn,  and 
does  learn,  to  play  fairly  in  the  thick  and  heat  of  a  struggle.  Such  qualities 
are  those  which  make  a  nation  brave  and  great.  The  game  is  manly  and 
fit  for  Englishmen  :  "  it  puts  a  courage  into  their  hearts  to  meet  an  enemy 
in  the  face." ' 

THE   ELEMENTS   OF    PHYSICAL   EDUCATION 

1.  TJie  exercises  should  be  adapted  to  meet  the  needs  of  each  individual 
case. 

It  is  to  be  borne  in  mind  that  the  object  of  a  proper  physical  education 
is  to  develop  health  and  not  strength,  to  bring  the  body  to  its  highest  degree 
of  perfection  and  not  to  convert  children  and  youths  into  gymnasts  and 
acrobats,  and  that  its  main  object  is  to  best  fit  the  individual  for  the  duties 


PHYSICAL  EDUCATION  GOT 

and  work  of  life  and  not  to  elicit  proficiency  in  mere  feats  of  sldll  and 
adroitness. 

It  must  not  be  forgotten,  moreover,  that  individuals  vary  greatly  in  the 
quality  of  their  physical  powers  and  in  their  capacity  for  muscular  exercise. 
It  is  just  as  impossible  to  form  a  great  mass  of  children  into  one  gymnastic 
class  as  it  is  to  place  those  children  in  one  school  standard  under  one 
teacher.  Neither  age,  height,  size,  nor  sex  affords  sure  means  of  classifying 
children,  so  far  as  the  needs  of  a  proper  physical  education  are  concerned. 
Each  individual  must  be  considered  upon  his  or  her  own  especial  merits,  and 
there  is  no  method  of  physical  training  which  is  universal  or  all-sufficing 
and  adapted  for  all  sorts  and  conditions  of  human  beings. 

The  sending  of  a  child  to  a  gymnasium,  or  the  placing  of  it  under  the 
care  of  a  drill-sergeant,  is  as  crude  a  procedure  as  the  conducting  of  a  child 
within  the  walls  of  the  first  school  met  with,  and  leaving  it  there  with  the 
impression  that  it  will  somehow  be  educated.  Physical  education  requires 
as  much  care  as  does  mental  education,  and  if  there  be  ten  '  forms,'  or 
'  standards,'  or  '  classes  '  in  a  school  which  is  concerned  in  mental  training, 
there  would  probably  be  at  least  as  many  forms  and  standards  in  any  insti- 
tution which  deals  with  the  training  of  the  body. 

Instructors  in  gymnastics  and  so-called  calisthenics  are  for  the  most  part 
somewhat  irresponsible  beings  ;  their  training  has  often  been  narrow  and 
incomplete,  and  their  methods  are  fixed  and  inelastic.  They  regard  their 
pupils  in  the  aggregate  and  not  as  individuals.  There  are  of  course  numerous 
striking  exceptions. 

It  is  to  be  hoped  that  a  time  will  come  when  those  who  profess  to  train 
the  body  will  be  required  to  produce  as  definite  evidences  of  fitness  as  is 
demanded  of  those  who  aim  at  training  the  mind. 

One  society  in  England — the  National  Health  Society — has  prepared  a 
scheme  for  the  examination  of  instructors  in  gymnastics  and  for  the  grant- 
ing of  diplomas  and  certificates  to  such  as  attain  to  the  prescribed  standard. 

Such  a  scheme  has  been  carried  out  in  America,  and  serves,  not  only  to 
do  justice  to  competent  teachers  on  the  one  hand,  but  to  protect  the  public 
on  the  other.  The  National  Health  Society  requires,  among  other  things, 
that  the  candidate  shall  possess  a  certain  knowledge  of  elementary  anatomy, 
of  the  physiology  of  bodily  exercise,  of  the  various  methods  of  physical 
training,  and  of  the  details  of  the  various  exercises  and  the  uses  of  all  gym- 
nastic apparatus  and  appliances.  The  candidate  is  required,  moreover,  to 
produce  evidence  of  physical  fitness  and  of  a  proper  training  in  some  recog- 
nised gymnasium  or  training  school. 

The  casual,  perfunctory,  and  unmethodical  manner  in  which  physical 
training  in  many  schools  is  carried  out  at  the  present  day  is  very 
lamentable. 

The  need  of  a  proper  training  is  especially  felt  in  girls'  schools,  in  schools 
which  are  patronised  by  the  lower  middle  class,  and  in  the  elementary  schools 
controlled  by  the  Education  Act. 

In  the  great  public  schools,  and  at  the  two  great  English  universities, 
physical  education  is  in  a  very  flourishing  and  exuberant  condition,  and  only  in 
need  perhaps  of  a  little  more  method,  a  little  more  science,  and  a  httle  more 
regard  for  the  individual  and  the  development  of  the  feeble  as  well  as  of  the 
strong. 

The  first  necessity  in  physical  education  is  a  knowledge  of  the  condition, 
the  wants,  and  the  possibihties  of  the  individuals  to  be  educated.  This  can 
only  be  obtained  by  an  individual  inspection.  It  would  be  well  if  in  the 
elementary  schools  a  plan  such  as  the  following  could  be  carried  out.     Each 


COS  HYGIENE 

cliild  on  entering   tlie   scliool  should  liave  a  book  in  wiiicb  tlie  following 
details  should  be  entered  : — 

1.  Name ;  2.  Age ;  3.  Height ;  4.  Weight ;  5.  General  aspect  and 
physique  (the  entries  under  this  heading  could  be  greatly  extended  and  bo 
made  of  much  service  if  a  competent  medical  man  made  the  inspection)  ; 
6.  Chest  girth  ;  7.  Breathing  capacity  ;  8.  Span  of  arms  ;  9.  Girth  of  arms  ; 
10.  Drawing  or  pulling  power  as  tested  ;  11.  Girth  of  legs  ;  12.  The  exist- 
ence of  any  evident  deformity,  defect,  or  disease.  (This  section  could  only 
be  properly  developed  by  a  medical  man.  The  conditions  dealt  with  would 
be  such  as  the  following :  spinal  curvature,  hernia,  rickets,  deformed 
thorax,  stiff  joints,  infantile  paralysis,  enlarged  tonsils,  glandular  disease, 
lung  disease,  condition  of  abdominal  viscera,  evidence  of  convulsions,  &c.) 

In  this  last  section  much  could  be  done  by  a  properly  trained  teacher, 
but  a  medical  inspector  would  render  the  evidence  in  every  way  of  greater 
value. 

The  child's  physical  condition  should  be  inquired  into  with  as  much 
care  as  is  exercised  in  examining  an  adult  for  life  insurance.  The  urine 
should  be  tested  if  possible,  and  if  the  parents  can  be  seen  the  child's  family 
history  should  be  inquired  into. 

Still,  apart  from  an  examination  by  a  medical  man,  the  twelve  points  pre- 
scribed -would  form  the  basis  of  a  valuable  record  and  place  the  physical 
education  of  the  child  upon  a  rational  footing.  Such  a  record  should  be  kept 
also  of  all  individuals  attending  gymnasia  and  undergoing  any  form  of 
physical  training.  Upon  the  evidence  afl'orded  the  precise  exercises  which 
were  desirable  and  the  precise  methods  of  training  to  be  carried  out  could  be 
determined. 

The  record  may  well  be  extended,  and  could  with  great  advantage  record 
a  test  of  the  child's  vision,  and  add  evidence  on  the  questions  of  astigmatism 
and  colour-blindness.  This  record,  kept  in  the  form  of  a  book,  should  be 
filled  up  every  three  months.  If  properly  kept,  the  value  of  such  a  book  would 
be  enormous.  To  the  individual  it  would  possess  more  than  mere  interest. 
It  would  show  the  history  of  his  early  life,  the  record  of  his  development,  and 
would  afford  an  admirable  guide  to  any  medical  man  should  the  individual 
in  the  future  become  the  subject  of  disease. 

Mental  training  is  exceedingly  important  without  doubt,  but  it  may  be 
that  the  time  will  come  when  the  Government  of  this  country  will  recognise 
the  importance  of  physical  training,  and  will  realise  that  among  the  children 
in  elementary  schools  a  strong  body  is  almost  as  important  as,  and  often  more 
useful  than,  a  well-stored  mind.  Many  of  these  children  are  turned  out 
into  the  Avorld  pale,  sickly,  ill-developed,  and  feeble.  That  at  present  many 
unremediable  causes  may  conspire  to  produce  this  is  evident  enough,  but  the 
state  of  things  is  susceptible  of  improvement.  The  health  and  strength  and 
physique  of  the  poorer  classes  may  be  placed  upon  a  better  basis,  and  a 
number  of  sturdy  and  strong  men  and  women  produced  in  the  place  of  the 
multitude  of  poor  creatures  who  after  a  more  or  less  doleful  and  useless 
life  become  prematurely  a  burden  upon  the  rates. 

The  systematic  examination  of  the  individual  and  the  conducting  of  a 
physical  education  upon  precise  and  scientific  grounds  have  already  been 
carried  out  in  some  cities  in  America. 

An  excellent  account  of  some  of  these  institutions  will  be  found  in  the 
record  of  the  Physical  Training  Conference  held  at  Boston  in  1889. 

2.  The  exercises  should  be  carefully  devised,  systematically  arranged, 
and  suitably  graduated. 

The  course  of  education  should  be  planned  upon  a  definite  system  and 


PHYSICAL  EDUCATION  609 

the  classes  formed,  and  when  occasion  demands  remodelled,  according  to  the 
physical  status  of  the  individual  members. 

The  exercises  must  be  graduated,  and  no  attempt  made  to  pass  from  one 
series  until  the  more  elementary  stages  have  been  mastered. 

It  is  of  especial  importance  than  none  of  the  more  comphcated,  difficult, 
and  arduous  exercises  should  be  forced  upon  those  who  are  physically  unfit. 
They  must  be  always — from  the  learner's  standpoint — moderate  and  pro- 
gressive. 

It  is  desirable  also  that  the  lessons  should  be  as  varied  and  as  interesting 
as  possible,  and  that  reasonable  opportunity  be  given  for  competition  and  the 
encouragement  of  those  who  are  specially  fitted  to  excel. 

The  exercises  should  aim  at  the  equal  employment  of  all  the  muscles,  and 
not  at  the  development  of  a  few.  The  work  in  an  ordinary  gymnasium  tends 
to  throw  strain  mainly  upon  the  upper  extremities,  while  most  of  the  out- 
door games  tend  to  develop  the  lower  limbs.  No  great  good  can  be  obtained 
from  tedious  drilling  and  purposeless  marching,  and  the  time  devoted  to 
physical  training  should  never  be  so  fully  absorbed  as  to  allow  no  leisure  for 
games  and  other  pleasant  forms  of  recreation. 

In  any  instance  violent  intermittent  exercises  should  be  forbidden,  and 
the  performance  of  feats  of  strength  should  never  come  within  the  scope  of 
the  educational  scheme. 

3.  The  exercises  should  he  carried  out  under  proper  guidance,  and  toith 
suitable  and  efficient  apparattis. 

The  teacher  should  be  capable  of  instructing  a  large  class — a  qualification 
which  is  not  commonly  possessed. 

4.  The  time  for  the  exercises  should  he  carefully  selected. 

Violent  exercise  after  a  full  meal  is  obviously  bad,  and  a  course  of 
physical  instruction  should  not  be  carried  out  in  the  case  of  children  who  are 
tired  from  a  long  day's  attendance  in  school,  or  who  are  feeble  for  want  of  food. 

In  the  matter  of  schools  it  is  well  that  the  period  for  physical  training 
should  be  interpolated  among  the  hours  devoted  to  ordinary  school  work.  If 
between  the  hours  of  nine  and  twelve  or  nine  and  one  the  children  could  be 
allowed  to  take  systematic  exercise  for  thirty  minutes,  either  in  the  open 
air  or  in  some  suitable  building  other  than  the  schoolroom,  they  would  be 
found  to  be  actually  refreshed  by  the  change  of  occupation,  to  enjoy  a  period 
of  mental  rest,  and  to  return  to  their  work  with  vigour. 

Another  half-hour  could  be  introduced  during  the  progress  of  the  after- 
noon lessons.  The  Eev.  E.  Warre,  one  of  the  masters  at  Eton,  advises  that 
a  schoolboy's  day  should  be  disposed  of  as  follows  :  Eest  ten  hours,  work 
seven  hours,  meals  and  play  seven  hours. 

So  far  as  adults  are  concerned,  the  taking  of  violent  exercise  in  the 
evening  after  a  long  and  arduous  day's  work  is  often  injurious  in  its  result. 

There  is  no  time  better  than  the  early  morning  before  the  labours  of  the 
day  are  commenced. 

Adults  who  have  been  accustomed  to  exercises  of  strength  and  endurance 
should  return  but  cautiously  to  such  pursuits  if  they  have  passed  through  a 
long  period  of  rest  from  exercise  and  are  out  of  condition.  A  man  may  ride 
fifty  miles  a  day  on  a  bicycle  very  easily  in  the  autumn,  but  he  would  be 
very  unwise  to  attempt  such  a  distance  in  the  following  spring,  provided  that 
he  had  taken  no  exercise  during  the  winter. 

5.  Exercises,  so  far  as  is  possible,  should  be  taken  in  the  open  air  or  in  a 
large  and  very  well-ventilated  room. 

6.  Those  who  are  taking  systematic  exercise  should  be  properly  clad. 
The  garments  should  be  light,  loose,  and  made  of  wool.     It  is  desirable 

VOL.  I.  R  R 


010  HYGIENE 

that  care  be  taken  not  to  catcli  cold  by  standing  about  in  clothes  which  are 
damp  with  perspiration. 

This  question  of  clothing  is  more  fully  dealt  with  in  another  section  of 
this  work. 

FOEMS   OF   EXEKCISE 

So  far  as  any  classification  can  be  made — and  it  must  of  necessity  be 
rough — exercises  may  be  divided  into  the  following  classes  : — 

1.  Exercises  of  Strength 

These  involve  actual  and  considerable  muscular  power,  and  are  illus- 
trated by  advanced  exercises  in  the  gymnasium,  with  apparatus  such  as  the 
horizontal  bar,  the  trapeze,  the  rings.  In  a  special  category  may  be  placed 
what  may  be  termed  feats  of  strength,  such  as  lifting  great  weights,  putting 
the  shot,  throwing  the  hammer,  and  the  like. 

These  exercises  involve  '  effort,'  i.e.  the  muscular  position  in  which  the 
man  takes  a  deep  breath,  and  then,  when  his  chest  is  full,  closes  his  glottis, 
so  that  he  may  make  the  thorax  a  fixed  base  from  which  the  upper  limbs 
can  act.  During  the  performance  of  the  movement  he  does  not  breathe, 
his  face  becomes  engorged,  and  the  veins  which  stand  out  upon  his  fore- 
head demonstrate  the  distended  condition  of  the  right  side  of  the  heart.  It 
is  during  *  effort '  that  some  sudden  and  fatal  accidents  have  occurred,  such 
&s  rupture  of  the  heart  and  the  giving  way  of  blood-vessels. 

2.  Exercises  of  Speed  or  of  Bapid  Movement 

These  include  running  in  all  its  forms  and  such  exercises  as  involve 
very  rapid  and  continued  movements.  The  individual  muscular  contrac- 
tions are  not  extreme,  but  they  are  very  quickly  repeated.  The  amount  of 
work  performed  is  distributed  over  a  considerable  period,  and  is  not,  as  in 
exercises  of  strength,  concentrated  into  a  few  moments. 

These  exercises  are  susceptible  of  considerable  modification,  and  range 
from  the  extreme  effort  of  the  sprint  runner  to  the  easier  movements  of  the 
paper-chaser  or  of  the  devotee  of  the  skipping-rope. 

Certain  forms  of  gymnastic  exercise  rank  in  this  class.  The  movements 
tend  to  develop  the  respiratory  capacity,  and  are  the  exercises  which  soon 
bring  about  the  state  of  breathlessness. 

3.  Exercises  of  Endurance 

In  these  the  muscular  effort  is  inconsiderable  at  any  given  moment,  and 
is  distributed  over  a  still  longer  period  of  time. 

Neither  breathlessness  nor  rapid  muscular  exhaustion  arrests  the  subject 
of  the  exercise.  The  continuance  of  his  movements  becomes  a  matter  merely 
of  endurance.  Walking  is  a  type  of  this  variety.  And  in  the  same  class 
must  be  placed  many  outdoor  games,  skating,  rowing  and  cycling,  drilling 
and  such  exercises  as  are  generally  included  under  the  term  Swedish  gym- 
nastics. 

In  the  training  of  the  body  the  exercises  of  endurance  must  occupy  the 
first,  the  most  prominent,  and  the  most  important  place. 

4.  Exercises  of  Skill 

are  illustrated  by  the  more  complex  gymnastic  exercises,  such  as  those 
which  involve  balancing,  &c.,  by  fencing  and  any  other  movements  which 
imply,  not  necessarily  severe  or  continued  muscular  exertion,  but  great  acti- 
vity of  the  brain  and  spinal  cord. 


PHYSICAL  EDUCATION  611 

The  fencer  in  his  earher  days  becomes  weary  in  his  body,  but  as  he 
becomes  more  experienced  he  '  feels '  the  exercise,  not  in  his  muscles,  but  in 
his  nervous  system. 

6.  Exercises  which  Develop  the  Chest 

may  on  account  of  their  importance  be  especially  classified.  The  exercises 
which  come  under  this  class  are  such  as  tend  to  develop  the  muscles  of  the 
chest — namely,  the  pectorals,  the  serratus  magnus,  the  latissimus  dorsi,  the 
anterior  abdominal  muscles,  and  some  others  of  lesser  importance. 

This,  however,  is  not  all.  As  Dr.  Lagrange  has  pointed  out,  the  size  of 
the  thoracic  cavity  can  only  be  increased  by  increasing  the  volume  of  its 
contents,  the  lungs.  '  It  is  from  within  outwards,'  writes  that  author,  '  that 
the  force  capable  of  expanding  the  chest  acts,  and  it  is  in  reality  to  the  lungs 
and  not  to  the  muscles,  that  the  chief  share  in  the  changes  in  form  and  size 
of  the  chest  belongs.  The  most  powerful  inspiratory  muscles  cannot  raise 
the  ribs,  unless  the  lungs  participate  in  the  movement  of  expansion,  and  on 
the  other  hand  the  lungs  can  raise  the  ribs  without  the  aid  of  the  muscles, 
for  the  chests  of  emphysematous  patients  remain  vaulted  in  spite  of  their 
efforts  to  lower  the  ribs  and  complete  the  respiratory  movement.  .  .  .  Moun- 
taineers all  have  large  chests,  and  the  Indians  who  live  on  the  high  plateaux 
of  the  Cordillera  in  the  Andes  have  been  noted  for  the  extraordinary  size  of 
their  chests.  .  .  .  Singers  with  no  other  exercise  but  singing  acquire  great 
respiratory  power  and  a  remarkable  increase  in  the  dimensions  of  their  chests.' 

The  exercises  needed,  therefore,  should  not  only  be  such  as  develop 
the  muscles  of  the  upper  part  of  the  trunk,  but  such  also  as  increase  the 
volume  of  the  respiratory  movements.  Among  the  latter  would  be  placed, 
so  far  as  children  are  especially  concerned,  running,  skipping,  rapid  limb 
movements,  and  active  exercises  in  the  open  air. 

Many  children  are  born  with  deformed  and  narrow  chests  which  they 
inherit  from  their  parents ;  in  others  the  thorax  has  been  distorted  by  rickets, 
by  lung  affections,  or  by  spinal  disease.  One  potent  factor  in  the  production 
of  a  narrow  chest,  outside  these  causes,  is  the  hypertrophied  tonsil. 

It  is  anomalous  to  press  a  child  to  take  exercises  requiring  vigorous 
respiratory  movements  when  enlarged  tonsils  so  block  up  the  opening  into 
the  air-passages  as  to  prevent  the  free  entrance  of  air. 

The  Selection  of  Exbkcises  ACcoEDiNa  to  Individual  Needs 

Children 

The  physical  training  of  children  should  be  commenced  early,  should  be 
made  as  interesting  as  possible,  and  be  represented  in  the  main  by  what  may 
he  termed  scientific  romping. 

The  exercises  should  be  given  whenever  possible  in  classes.  To  set  a 
child  to  execute  formal  movements  with  dumb-bell  or  bar-bell  when  alone, 
and  to  march  with  no  one  for  company,  is  a  little  dismal. 

The  set  exercises  should  not  be  too  formal,  and  never  be  too  long,  and  in 
no  instance  should  they  be  allowed  to  take  the  place  of  the  ordinary  outdoor 
games  of  children. 

Games  which  involve  shouting  should  be  encouraged,  and  a  very  promi- 
nent position  given  to  running,  skipping,  games  with  balls,  and  jumping. 
The  most  rudimentary  of  all  games,  '  touch,'  is  one  of  the  most  excellent. 
The  upper  limbs  may  be  encouraged  by  such  amusements  as  battledore  and 
shuttlecock  and  the  lower  by  such  a  game  as  hop-scotch. 

K  E  2 


612  HYGIENE 

The  set  exercises  should  take  the  form  of  what  are  Icnowii  as  Swedish 
gymnastics,  the  vocal  march,  musical  drill,  aud  the  class  exercises  with 
dumb-bell  and  bar-bell. 

Children  should  avoid  exercises  of  strength  and,  in  the  main,  exercises  of 
speed.  They  are  best  suited  for  exercises  which  involve  moderate  endurance 
and  such  as  require  no  great  mental  effort  to  follow. 

In  the  matter  of  gymnastic  apphances  there  is  little  need  of  especial  work. 
The  subject  is  considered  in  the  description  of  gymnastic  apparatus.  The 
principal  of  these,  from  the  children's  standpoint,  are  the  climbing  rope,  the 
inclined  ladder,  the  vaulting  horse,  the  parallel  bars. 

Girls  and  Women 

The  physical  condition  of  a  large  proportion  of  the  girls  and  women  in 
this  country  is  quite  deplorable,  especially  among  the  middle  and  upper 
classes.  A  well-developed  perfectly  proportioned  girl  who  is  possessed  of  normal 
muscular  strength,  who  can  walk  naturally,  and  can  carry  herself  with  grace, 
attracts  attention.  The  WTctched  physical  state  of  a  large  proportion  of 
modern  girls — especially  of  those  who  inhabit  the  large  towns — is  apt  to  be  as- 
cribed, not  to  a  totally  neglected  education,  but  to  the  belief  that  growing  girls 
are  always  awkward,  uncouth,  and  weedy.     This  beHef  is  not  well  founded. 

The  unfortunate  girl  is  encouraged  to  be  dull,  to  be  prim,  to  be  subdued, 
to  suppress  the  outbursts  of  pure  animal  spirits.  She  is  more  or  less  under 
the  curse  of  that  detestable  adjective  '  lady-like.'  She  spends  hours  in  an 
ill-ventilated  schoolroom  and  upon  a  piano  stool,  and  the  rest  of  her  time 
is  occupied  in  eating  and  sleeping,  in  preparing  lessons,  in  stooping  over 
needlework,  and  in  taking  formal  walks  with  the  governess.  Her  clothes  are 
probably  a  collection  of  hygienic  errors. 

It  is  not  to  be  wondered  that  a  girl  so  fostered  is  often  a  melancholy 
specimen  of  her  species.  She  may  be  highly  educated  and  the  mistress  of 
many  accomplishments,  she  may  be  cultured  and  '  refined '  according  to 
the  boarding-school  standard,  but  she  will  at  the  same  time  be  probably 
more  or  less  imfitted  for  the  struggle  of  life  and  the  mere  circumstances 
w^hich  attend  Uving. 

There  is  something  about  the  '  higher  education '  of  the  modern  girl 
which  is  comparable  to  the  manufacture  of  the  finest  Sevres  china.  The 
result  is  beautiful  from  the  designer's  standpoint,  but  the  cup  is  delicate  ;  it 
cannot  be  used  in  daily  hfe,  and  it  must  be  kept  in  a  cabinet. 

A  good  digestion  and  an  active  liver  are  more  useful  in  the  battle  of  life 
than  a  knowledge  of  advanced  mathematics,  and  sturdy  limbs  and  strong 
hands  are  of  more  value  to  the  mother  of  children  than  even  decimal 
fractions  and  a  familiarity  with  irregular  verbs. 

The  lady-like  girl  is  encouraged  to  keep  her  hands  '  fine,'  to  have  them 
compressed  by  gloves  and  protected  from  Hght,  and  to  use  them  as  little  as 
possible  in  order  that  she  might  produce  the  wan,  feeble  appendage  wliich 
constitutes  the  lady-like  hand,  and  which  is  put  to  httle  more  use  than  to  set 
off  a  few  rings.  The  face  must  be  protected  from  the  sun  by  sunshades 
and  veils,  the  pink  and  white  complexion  of  the  invahd  must  be  imitated. 
It  would  appear  that  the  lady-hke  are  always  dehcate,  and  a  certain  unobtru- 
sive feebleness  and  flabbiness  are  signs  of  refinement.  For  use  and  influence 
in  the  world,  for  a  capacity  to  enjoy  the  purest  pleasures  of  life,  and  as  an 
example  of  all  the  finest  qualities  of  womanhood,  no  one  among  the 
'  higher  educated '  can  compare  with  such  an  one  the  *  Nut  Brown  Maid.' 
The  ballad  of  the  '  Nut  Brown  Maid '  might  well  be  engraved  upon  the  wall 
of  every '  finishing '  school  for  young  ladies. 


PHYSICAL  EDUCATION  613 

A  neglected  physical  education  produces  a  sorry  object— a  pale  child 
■with  a  poking  head,  a  narrow  chest,  an  unshapely  back,  a  shuffling  or 
mincing  gait,  and  an  ungainly  carriage.  She  is  without  grace  and  with- 
out the  capacity  for  vigorous  physical  enjoyment.  Her  ankles  and  wrists 
are  clumsy,  her  complexion  is  dull,  and  if  her  circulation  be  bad — as  is  not 
unusual — her  sodden-looking  purplish  arms  are  covered  with  a  fine  down. 
When  she  grows  up  to  womanhood  she  finds  herself  unfitted  for  the  duties 
and  responsibilities  of  a  wife  and  mother.  She  has  little  strength  to  with- 
stand the  hardships  of  life  and  less  capacity  to  enjoy  its  pleasures.  She  is 
nervous,  querulous,  frail,  and  in  more  respects  than  one  a  poor  creature. 
Walking  makes  her  tired,  the  sea  makes  her  sick,  the  sun  makes  her  head 
ache,  the  wind  makes  her  chilly,  effort  of  any  unusual  kind  reduces  her  to  a 
general  wreck.  The  number  of  women  who  can  travel  without  fussing  and 
knocking  up,  and  who  can  climb  a  ship's  side  and  make  their  way  across  a 
heavy  moor,  and  can,  indeed,  become  companions  to  their  husbands  and 
brothers  in  the  milder  of  these  outdoor  sports  is  not  considerable. 

Younger  girls  may  pursue  the  exercises  named  in  dealing  with  the  edu- 
cation of  children.  Those  who  are  a  little  older  have  an  infinite  variety  of 
healthy  pursuits  at  their  service — running,  skipping,  outdoor  games  of 
all  kinds,  riding,  skating,  swimming,  cricket,  games  with  balls,  archery, 
tennis,  climbing  (in  a  moderate  form),  and  certain  exercises  in  the  gymna- 
sium. They  should  practise  also  such  movements  as  develop  the  abdominal 
muscles  and  should  never  neglect  rowing. 

Fencing  in  moderation  is  admirable ;  a  tendency  to  flat  feet  and  weak 
ankles  may  be  met  by  such  simple  games  as  hop-scotch,  by  dancing  (in  the 
open  air),  by  learning  Scotch  dances  and  the  hornpipe.  Cycling  may,  I 
think,  be  avoided,  and  I  am  under  the  impression  that  jumping  may  well  be 
dispensed  with  in  girls  who  have  passed  the  period  of  puberty. 

For  women  such  exercises  as  have  been  just  detailed  are  open,  with  the 
obvious  modifications  which  their  age  and  dispositions  suggest. 

Eowing  is  an  admirable  exercise  for  women  up  to  almost  any  age. 

The  matter  of  clothing  need  only  be  briefly  alluded  to.  It  is  of  little  use 
to  expect  great  good  from  walking  exercises  if  tight  boots  are  worn,  with 
high  ankles  and  high  heels.  Corsets  are  an  abomination,  and  rowing  in 
corsets  forms  a  means  of  developing  a  pendulous  abdomen  and  the  conditions 
which  lead  to  hernia. 

Lads 
between   fourteen  and   eighteen  have   almost  every  form  of  exercise  and 
physical  recreation  open  to  them.     They  should  avoid  exercises  of  strength 
and  feats  of  strength  and  exercises  of  extreme  speed  such  as  sprint  running. 

Adults 
between  eighteen  and  twenty-five  have  the  whole  of  the  joys  of  the  athletic 
world  open  to  them,  and  if  a  man  keep  in  training  and  in  practice  his  period 
of  athletic  life  may  be  extended  to  thirty. 

The  Middle-aged  and  Elderly 
must  anticipate  a  progressive  curtailment  of  their  more  active  pursuits. 
There  remain,  however,  walking  and  all  the  milder  forms  of  outdoor  exercise 
— riding,  skating,  cycling,  and  the  use  of  the  simpler  gymnastic  apparatus. 
After  thirty  very  few  individuals  indeed  are  capable  of  undertaking  exercises 
of  speed  without  actual  risk. 


BATHS 


BY 


W.   HALE   WHITE,   M.D.,   F.E.C.P.  Lox\d. 

PHYSICIAN  TO  GUY'S  HOSPITAL  AND  LECTURER  ON  MATEUIA  MEDICA 
AND  THERAPEUTICS 


BATHS 

HISTOEY   OP  BATHS 

It  is  altogether  beyond  the  scope  of  an  article  such  as  this  to  give  a 
history  of  baths.  It  would  occupy  too  much  space,  and  much  of  it  would  be 
uninteresting  to  the  medical  reader.  It  will,  however,  be  worth  while  to 
give  a  short  sketch  of  the  history  of  baths  so  far  as  it  concerns  the  student 
of  medicine. 

Bathing  is  as  old  as  the  hills  ;  we  find  evidences  of  it  far  back  in  his- 
tory, and  at  the  present  day  savage  tribes  often  attach  great  importance  to 
the  curative  effects  of  water.  It  is  the  custom  of  the  Fiji  women  to  take  a 
sea  bath  immediately  after  their  confinement,  with  the  object  of  accelerating 
their  recovery.  The  belief  in  the  healing  efficacy  of  water  is  sometimes  so 
strong  that  it  becomes  a  religious  belief.  Thus  we  have  the  practice  among 
the  Hindoos  of  bathing  in  the  Ganges,  or  in  the  sacred  lakes  around  their 
temples ;  we  have  the  baths  of  purification  ordered  by  the  law  of  Moses, 
and  they  are  also  required  by  the  Talmud  and  by  the  code  of  religion  of  the 
Mahommedans,  The  story  of  Naaman  is  another  instance  of  the  old  belief 
in  the  medicinal  virtues  of  baths.  In  the  traditions  of  the  mythical  period 
of  Greek  history  we  find  abundant  allusions  to  the  practice  of  bathing. 
Later  we  find  Hippocrates  writing  on  the  subject.  In  his  work  on  '  Air, 
Water,  and  Places,'  that  on  the  '  Usage  of  Liquids,'  and  also  in  that  on 
*■  Diet  and  Kegimen,'  there  are  exact  directions  as  to  the  employment  of 
water  in  therapeutics.  Among  the  Eomans  bathing  reached  great  perfection  : 
for  a  full  description  of  all  their  baths  the  reader  may  consult  the  article  on 
'  Baths  '  in  the  '  Encyclopfedia  Britannica,'  Musa  and  Charmis  were  the  two 
physicians  who  most  advocated  the  work  of  baths  in  medicine.  Musa 
attained  great  fame  because  Augustus  recovered  under  his  care,  and  part  of 
the  treatment  was  the  use  of  cold  water  thrown  over  the  body  after  warm 
baths  and  vapour  baths.  Under  Charmis  the  use  of  cold  baths  became  very 
popular,  and  Pliny  gives  an  account  of  the  Eoman  senators  who  sat 
shivering  after  the  cold  baths  which  Charmis  had  ordered  them.  He  em- 
ployed them  with  such  rigour  that  a  controversy  sprang  up  as  to  whether 
they  were  really  so  useful  as  he  contended,  and  for  a  time  they  were  not 
popular.  Galen  advocated  cold  baths,  but  condemned  their  excess,  and 
recommended  the  use  of  cold  water  to  the  head  while  the  body  was  in  a 
warm  bath.  During  the  medical  barbarism  of  the  Middle  Ages  baths  fell 
into  disrepute. 

Among  the  Arabian  physicians,  Ehazes  alone  advocated  cold  baths,  and 
he  advised  their  use  in  the  treatment  of  small-pox,  and  used  rose-water  for 
burns.  It  is  not  until  1699  that  we  again  find  baths  attracting  the  attention 
of  the  medical  profession.  In  that  year  Floyer,  an  English  physician  at 
Lichfield,  pubHshed  his  book  entitled  '  An  Inquiry  into  the  Eight  Use  of 
Baths,'  and  he  recommended  many  applications  of  them. 

In  the  eighteenth  century  the  chief  interest  in  baths  was  seen  in  Italy, 
and  one  historian  of  the  period  states  that  '  all  Italy  is  crazy  on  the  subject 
of  cold  water.'  At  the  same  time  the  Hahn  family  in  Germany,  consisting 
of  two  brothers  and  a  son,  all  strongly  recommended  the  use  of  cold  baths 


G18  HYGIENE 

for  various  medical  ailments.  Joliann  Sigismond  Halin  published  a  work 
on  the  subject  in  17-13.  He  applied  cold  water  to  the  treatment  of  fevers, 
especially  small-pox,  measles,  and  erysipelas,  and  used  it  also  for  many 
chronic  diseases.     In  Kussia,  likewise,  the  use  of  baths  became  fashionable. 

France  also  took  up  the  movement.  Surgeons,  reviving  the  practice  of 
Ambroise  Pare,  advised  the  use  of  cold  water  for  the  treatment  of  wounds. 
The  most  ardent  French  advocate  for  cold  baths  was  Pomme,  and  he  treated 
all  diseases  of  the  nervous  system  by  placing  the  patients  in  cold  baths  of  a 
temperature  of  50°  F.,  and  leaving  them  there  for  from  six  to  twenty-four 
hours.  His  theory  was  that  by  the  cold  baths  he  infiltrated  the  nerves  with 
water,  and  thereby  drove  the  disease  out  of  them. 

The  first  physician  who  treated  the  subject  of  baths  at  all  scientifically 
was  Currie,  of  Liverpool,  who,  being  on  board  ship  with  Dr.  Wright,  of 
Edinburgh,  when  the  latter  had  typhus  fever,  treated  him  by  throwing 
buckets  of  cold  water  over  him.  Dr.  Wright  was  so  much  improved  by  this 
treatment  that  Currie  was  led  to  adopt  it  in  many  forms  of  fever,  amongst 
others  typhus,  small-pox,  scarlet  fever,  and  measles.  He  was  very  successful, 
and  published  in  1797  his  medical  reports  on  the  'Effects  of  Cold  Water  in 
Febrile  Maladies.'  This  book  sold  largely,  for  it  soon  reached  its  fourth 
edition.  The  great  merit  of  Currie's  work  was  that  he  observed  accurately 
how  much  the  application  of  cold  reduced  the  symptoms  of  fever.  Shortly 
after  him  Giannini,  in  Italy,  used  cold  water  for  fevers.  He  preferred  the  cold 
bath,  while  Currie  had  used  cold  affusions. 

In  1789  Vincent  Priessnitz  was  born  in  Silesia.  He  was  of  very  humble 
origin,  and  had  no  scientific  knowledge.  When  about  twenty  he  broke  his 
ribs,  and  he  treated  himself  by  the  application  of  a  cold  water  bandage. 
The  ribs  healed,  and  he  attributed  the  cure  to  the  action  of  the  cold  water.  He 
then  roamed  all  over  the  country  treating  human  beings  and  animals  by 
cold  water  in  a  most  haphazard  manner,  quite  irrespective  of  the  maladies 
from  Avhich  they  might  be  suffering.  The  peasants  attributed  his  success  to 
sorcery,  but,  anyhow,  he  became  immensely  popular,  and  the  little  village  of 
Greifenberg,  where  he  settled  down,  soon  became  a  town  full  of  hotels  to 
accommodate  the  thousands  who  came  to  be  treated  by  him.  The  Austrian 
Government  appointed  a  medical  commission  to  examine  the  subject,  and 
they  reported  favourably  upon  the  treatment  of  certain  diseases  by  baths, 
and  thus,  although  Priessnitz  was  an  ignorant  quack,  he  became  the  means 
of  bringing  the  subject  of  baths  before  the  medical  profession.  He  amassed 
an  immense  fortune,  but  left  no  record  of  any  scientific  value. 

From  that  time  till  now  such  an  impetus  was  given  to  the  subject  that 
baths  have  become  very  popular.  It  is  true  that  between  about  1825  and 
1860  there  was  a  temporary  lull  in  some  branches  of  the  subject ;  but  since 
the  latter  date  the  work  of  scientific  men,  such  as  Liebermeister,  Jiirgensen, 
and  others,  has  thoroughly  elucidated  the  subject.  In  the  following  pages  we 
shall  see  that,  although  baths  are  of  great  value,  their  importance  has  been 
immensely  overrated  by  all  sorts  of  impudent  quacks,  who  issue  pretentious 
advertisements  designed  to  attract  persons  to  particular  bathing  establish- 
ments in  which  these  quacks  have  a  pecuniary  interest. 


FORMS  OF  BATHS 

Baths  are  divided  into  general  and  local.  A  general  bath  is  one  in  which 
the  whole  body,  save  the  head,  is  immersed.  A  local  bath  is  one  in  which 
only  some  part  of  the  body  is  immersed.     The  local  baths  which  have  re- 


BATHS  CIO 

ceived  names  are  the  occipital  bath,  the  elbow  bath,  the  hand  bath,  the  sitz 
or  hip  bath,  and  the  foot  bath.  Sometimes  the  word  '  bath  '  is  used  even  when 
no  part  of  the  body  is  immersed  ;  thus  we  have  a  shower  bath.  Closely  allied 
to  baths  are  those  local  applications  of  water  in  which  it  is  made  to  play 
upon  a  part  of  the  body  in  the  form  of  a  spray  or  douche.  There  are  a  great 
many  varieties  of  these  at  all  bathing  establishments.  The  water  is  generally 
projected  upon  the  part  with  considerable  force,  and  its  temperature  is 
capable  of  being  modified  while  the  douche  is  in  action.  Sprays  and  douches 
have  been  named  either  according  to  the  part  of  the  body  to  which  the  water 
is  applied,  such  as  the  rectal  douche,  the  vaginal  douche,  or  according  to  the 
shape  of  the  stream  that  is  ejected.  There  is  no  need  to  recapitulate  all  the 
foohsh  and  fantastic  names  that  have  been  thus  applied.  Water  may  be 
locally  applied  to  parts  without  actually  coming  in  contact  with  them.  It  is 
then  solely  used  to  produce  local  alterations  in  temperature.  Leiter's  coils 
are  an  instance  of  its  employment  in  this  manner,  and  various  sounds,  elastic 
bags,  or  catheters,  through  which  cold  or  warm  water  is  made  to  circulate, 
have  to  be  used  in  the  treatment  of  diseases  of  the  uterus,  vagina,  rectum, 
and  urethra.  Water  in  the  form  of  ice  is  applied  to  parts  by  being  placed  in 
india-rubber  bags  which  are  placed  on  the  skin  ;  Chapman's  spinal  ice-bag 
and  the  ordinary  ice-bag  applied  to  the  head  for  concussion  are  instances  of 
its  use  in  this  manner.  Lastly,  it  is  frequently  applied  locally  by  means  of 
cloths,  flannels,  or  lint,  rinsed  out  in  hot  or  cold  water,  which  then  forms 
either  a  compress  or  a  fomentation.  If  these  are  covered  over  with  gutta- 
percha, they  retain  the  heat  of  the  body,  and  so  act  like  a  poultice. 

The  Physiological  Action  of  Baths  consideeed  according  to 

THEIR    TeMPEEATUEE 

We  shall  have  under  this  heading  to  consider  the  influence  upon  the  body 
of  (1)  indifferent  baths  or  those  in  which  a  healthy  person  feels  neither  hot 
nor  cold  ;  (2)  cold  baths  or  those  in  which  a  healthy  person  feels  cold,  and 
(3)  warm  baths  or  those  in  which  a  healthy  person  feels  warm.  Popular 
terms  used  for  varieties  of  these  will  be  mentioned  under  each  heading. 
Delmas  gives  the  following  table  showing  the  temperature  of  water  baths,, 
which  are  named  according  to  their  temperature  : — 

Excessively  cold  .        . 

Very  cold 

Cold     .... 

Moderately  cold  or  fresh 

Slightly  cold 

Tepid  .... 

Warm  .... 

Ve/y  warm  . 

Excessively  warm 

All  people  are  not  equally  sensitive  to  the  effect  of  heat  and  cold,  so  that  no 
precise  classification  can  be  given. 

Indifpeeent  Baths 

Water  is  a  very  much  better  conductor  of  heat  than  air.  From  this  it 
follows  that  the  indifferent  temperature  of  water  is  much  higher  than  that 
of  air.  In  a  perfectly  still  atmosphere  a  naked  person  feels  neither  hot  nor 
cold  if  its  temperature  be  somewhere  between  Ql^  and  77°  F. ;  but  the  indif- 


Deg.  Cent. 

Deg.  "Fahr. 

Oto  6 

32  to  42-8 

7  „  10 

44-6  „  50 

11  „  15 

51-8  „  59 

16  „  20 

60-8  „  68 

21  „  25 

69-8  „  77 

26  „  30 

78-8  „  86 

31  „  35 

87-8  „  95 

36  „  40 

96-8  „  104 

41  „  60  or  70 

105-8  „  140  or  15 

620  HYGIENE 

ferent  temperature  of  water  varies  for  different  persons  from  88°  to  98°  F. 
An  indifferent  bath,  however  long  its  duration,  produces  no  alteration  in  the 
bodily  temperature.  After  it  there  is  a  pleasant  feeling  all  over  the  body, 
and  there  may  be  a  slight  loss  of  heat  from  the  evaporation  of  the  water  that 
has  been  left  on  the  skin,  and  therefore  it  is  always  advisable  that  the  bather 
should  dry  himself  quickly  after  the  bath.  There  is  no  alteration  in  the 
amoimt  of  urea  and  carbon  dioxide  subsequently  excreted ;  but  the  amount 
of  urme  passed  is  said  to  be  sometimes  slightly  increased.  The  pulse  and 
respiration  are  unaltered.  Some  authors  state — but,  as  we  shall  see  later  on, 
Avithout  sufficient  eAddence — that  the  skin  is  capable  of  absorbing  water  from 
an  indifferent  bath.  Water  being  so  much  denser  than  air,  the  total  pressure 
on  the  surface  of  the  body  must  be  considerably  greater  in  a  water  bath  than 
in  the  air  ;  but  we  do  not  know  of  any  effects  that  can  be  attributed  to  this. 
An  indifferent  bath  is  often  popularly  called  a  warm  bath,  while  one  interme- 
diate between  warm  and  cold  is  spoken  of  as  tepid. 

Cold  Baths 

A  cold  bath  abstracts  heat  from  the  body  just  the  same  as  it  would  from 
anything  else  with  a  higher  temperature  than  the  water  of  which  it  was 
composed.  But  with  healthy  individuals  taking  an  ordinary  cold  bath,  the 
loss  of  heat  is  not  demonstrable  by  the  thermometer,  for  the  production  of 
heat  is  increased.  In  apparent  contradiction  to  this  statement  is  the  fact 
that  MacHster  ('  The  Nature  of  Fever,'  1887)  has  shown  that  cold  has  the 
effect  of  abolishing,  or  at  any  rate  greatly  diminishing,  the  thermogenetic 
function  of  muscle.  But  then  it  must  be  remembered  that  he  used  extreme 
applications  of  cold.  Thus  in  one  of  his  experiments  he  found  that  when  an 
animal  was  cooled  16°  C.  the  power  of  its  muscles  to  produce  heat  when 
stimulated  was  almost  abolished ;  but  that  when  it  was  warmed  up  again  to 
the  former  temperature  the  thermogenetic  power  returned.  Fred^ricq  and 
Quinquand  (quoted  by  Dujardin-Beaumetz,  '  Therapeutic  Gazette,'  Feb. 
1888)  state  that  in  a  healthy  individual  taking  an  ordinary  cold  bath,  owing 
to  the  contraction  of  the  cutaneous  vessels  the  blood,  and  consequently  the 
muscles,  are  but  slightly  cooled,  and  in  such  a  bath  the  absorption  of  oxygen, 
the  ehmination  of  carbonic  acid  gas,  and  thermogenesis  are  increased.  This 
effect  is  most  probably  due  to  the  stimulation  of  the  skin  by  the  cold  water, 
and  the  consequent  reflex  affection  of  the  nerves  which  preside  over  the 
thermogenetic  function  of  muscle — that  is  to  say,  over  the  decomposition  of  its 
thermogen,  a  term  which  has  been  applied  to  such  substances  in  muscle  as 
produce  heat.  These  same  researches  of  Fredericq  and  Quinquand  show  that 
if  the  application  of  cold  be  very  prolonged,  or  if  the  cold  be  very  great, 
the  absorption  of  oxygen  and  the  excretion  of  carbon  dioxide,  which  may  be 
taken  as  indications  of  the  amount  of  thermogenesis,  fall  below  the  normal 
point,  thus  really  confirming  Maclister's  statements.  The  radiation  of  heat 
must  be  considerably  diminished  by  immersion  in  cold  water ;  but  there  is 
no  evidence  to  show  how  much  it  is  affected  by  a  bath.  Probably  all  these 
conclusions  are  not  precisely  applicable  to  a  patient  suffering  from  fever, 
although,  no  doubt,  in  the  main  the  same  considerations  will  apply ;  but 
owing  to  the  dilatation  of  the  cutaneous  vessels  which  so  commonly  exists  in 
fever,  the  blood  is  cooled  and  thus  the  thermogenetic  function  of  the  muscles, 
owing  also  to  their  being  likewise  quickly  cooled,  is  sooner  depressed  than  in 
health.  But,  even  in  a  fever  patient,  the  first  effect  of  a  cold  bath  is  probably 
at  first  to  increase  thermogenesis  ;  but  soon  the  activity  of  this  function  de- 
creases, and  it  may  continue  to  be  considerably  depressed  even  for  some  time 


BATHS  621 

after  the  patient  is  taken  out  of  the  bath.  For  a  fuller  account  of  the  appli- 
cation of  a.  cold  bath  for  fever  the  reader  is  referred  to  the  writer's  '  Text- 
book of  General  Therapeutics.' 

The  effect  of  a  cold  bath  upon  the  actual  temperature  of  the  body  has 
been  carefully  studied  by  many  observers.  If  the  bath  is  moderately  long 
and  not  very  cold,  the  bodily  temperature  remains  constant  because  of  the 
balancing  of  the  loss  and  of  the  production  of  heat.  Liebermeister  in  1859 
showed  that  if  the  bath  be  very  cold  the  internal  temperature  rises  slightly. 
For  example,  he  found  a  slight  rise  of  the  rectal  temperature  was  caused  by 
a  bath  of  86°  F.  lasting  twenty-five  mimutes.  Jacob,  Kemig,  and  others 
have  confirmed  these  results.  In  one  experiment  the  temperature  of  the 
blood  rose  as  much  as  3°"6  F. 

Probably,  however  cold  the  bath,  there  is  at  first  a  shght  rise  of  the 
internal  temperature  ;  but,  if  the  water  be  very  cold,  this  is  too  transient  to 
be  noteworthy,  and  we  get  only  a  sinking  of  the  whole  temperature  of  the 
body,  both  external  and  internal.  The  same  effect  may  be  produced  by  a 
moderately  cold  bath  if  it  be  continued  sufficiently  long.  Thus  Jiirgensen 
found  that  long-continued  baths  of  a  temperature  of  60°  F.  usually  caused  a 
rapid  sinking  of  the  temperature  of  the  body.  Liebermeister  says  that 
most  persons  can  bear  baths  of  a  temperature  of  68°  F.  to  75°  F.  for,  on  the 
average,  twenty  minutes  before  their  temperature  sinks  below  what  it  was 
previous  to  the  commencement  of  the  bath.  The  fall  of  temperature  is 
naturally  greatest  on  the  surface  and  least  in  the  interior  and  in  the  folds  of 
the  .skin.  For  example,  in  one  of  Jacob's  experiments  the  temperature  of  the 
skin  sank  in  a  cold  bath  lasting  sixteen  minutes  from  62°'6  to  48°*2  F.,  but 
that  of  the  axilla  only  sank  1°  F. 

After  the  discontinuance  of  a  bath  which  was  not  sufficiently  cold,  nor 
long  enough  to  cause  a  fall  of  the  bodily  temperature,  there  is  a  short  period 
during  which  it  falls  a  little  lower  than  before  the  bath.  This  is  called  by 
Liebermeister  the  primary  after-effect.  The  slight  rise  of  temperature  which 
succeeds  this  is  called  by  Jiirgensen  the  secondary  after-effect.  The  primary 
after-effect  is  due  in  part  to  the  fact  that  the  cutaneous  vessels  which  were 
contracted  during  the  bath  rapidly  dilate  again  when  the  bather  leaves  it,  and 
thus  there  is  a  greatly  increased  radiation  of  heat,  the  effect  of  which  in  coohng 
the  bodily  temperature  is  augmented  by  the  diminution  of  heat-production 
which,  as  Liebermeister  has  shown,  directly  follows  the  leaving  of  the  bath  and 
is  probably  to  be  looked  upon  as  compensatory  to  the  increased  heat-produc- 
tion which  took  place  during  it.  The  following  figures  from  Leichtenstern 
show  the  great  loss  of  heat  occasioned  by  a  cool  bath.  He  says,  if  we 
observe  in  a  man  who  is  healthy  and  not  unnaturally  stout  the  loss  of  heat 
which  takes  place  in  a  bath  of  the  duration  of  fifteen  to  twenty-five  minutes, 
it  is  found  that  in  a  bath  of  93°"2  F.  the  loss  of  heat  nearly  corresponds  with 
the  ordinary  average  loss ;  in  a  bath  of  86°  F.  it  reaches  twice,  in  a  bath  of 
77°  three  times,  in  a  bath  of  68°  F.  more  than  five  times  the  average  loss. 

Local  withdrav^als  of  heat,  such  as  partial  baths  and  cold  douches,  have 
the  same  effects,  but  to  a  less  extent. 

All  authors  are  agreed  that  a  cold  bath  greatly  augments  the  tissue- 
waste  in  the  body.  Braun  says  that  the  amount  of  carbon  dioxide  ex- 
creted may  sometimes  be  increased  as  much  as  from  300  to  500  per  cent. 
Eoughly  speaking,  this  increase  is  proportionate  to  the  increased  production 
of  heat.  Liebermeister  found  that  in  a  bath  of  only  90°*3  F.  the  excretion 
of  carbon  dioxide  was  shghtly  increased,  but  with  a  bath  of  64°-4  F.  it 
was  increased  to  three  times  the  normal  amount.  The  increase  in  the 
excretion  of   carbon  dioxide  continues  for  a  short  time    after  the  patient 


622  HYGIENE 

leaves  the  bath.  This  is  due  in  part  at  least  to  the  fact  that  the  increase  in 
excretion  will  continue  to  be  evident  for  some  httle  time  after  the  increased 
production,  which  is  the  cause  of  the  greater  excretion,  has  stopped.  Rohrig 
and  Zuntz  have  both  of  them  shown  by  means  of  their  experiments  upon 
rabbits  that  this  increase  in  the  excretion  of  carbon  dioxide  is  accompanied 
by  a  corresponding  increase  in  the  amount  of  oxygen  taken  in. 

If  the  bath  be  so  cold  or  so  long  that  the  temperature  of  the  body  begins 
to  fall,  then  the  increased  excretion  of  carbon  dioxide  gradually  lessens, 
till  at  last  the  amount  excreted  may  be  even  less  than  it  was  before  the  bath. 
Here  also  the  amount  of  oxygen  taken  in  decreases  proportionately  to  the 
diminution  in  the  amount  of  carbon  dioxide  excreted.  These  variations  in 
the  excretion  of  carbon  dioxide  are  directly  caused  by  the  variations  in 
the  production  of  heat,  which,  in  their  turn,  are  due  to  a  greater  or  less 
decomposition  of  thermogen,  owing  to  the  reflex  stimulation  of  the  nerves  of 
skin  by  contact  with  the  cold  water.  Experiments  made  upon  animals  give 
the  same  results  as  observations  upon  man.  Many  observers  have  worked 
at  the  subject.  Euhrig  and  Zuntz  and  Colasanti  used  rabbits,  Finkler 
employed  guinea-pigs,  and  Duke  Carl  Theodore  used  cats. 

A  local  application  of  cold  produces  precisely  the  same  effects  upon  tissue- 
metamorphosis  as  does  a  cold  bath,  but  they  are  less  in  amount. 

Leichtenstern  says  that  excretion  of  urea  is  not  altered  by  a  cold  bath 
unless  the  temperature  of  the  body  is  considerably  lowered  by  it.  The  fol- 
lowing authorities  agree  with  him  in  this  statement.  Liebermeister  found, 
in  experiments  he  made  in  1859,  that  cold  baths  produced  no  alteration  in 
the  amoimt  of  urea  excreted,  if  the  patients  remained  on  the  same  diet. 
Senator  experimented  with  dogs,  and  came  also  to  the  conclusion  that  a 
diminution  of  the  external  temperature  produced  no  change  in  the  excretion 
of  urea.  Voit's  experiments  gave  a  like  result.  Probably,  if  the  cold  be  very 
great  or  very  prolonged,  the  excretion  of  urea  may  be  altered.  Braun  simply 
states  that  a  cold  bath  increases  the  excretion  of  it,  without  saying  at  what 
temperature  this  takes  place. 

Turning  now  to  the  effects  of  a  cold  bath  upon  circulation  and  respira- 
tion, the  most  obvious  result  is  that  the  cutaneous  vessels  will  be  contracted. 
If  the  bath  be  excessively  long  continued  or  very  cold  this  contraction  is  suc- 
ceeded by  a  paralytic  dilatation,  and  this  accounts  for  the  bluish-red  colour  of 
the  skin  so  often  seen  after  a  cold  bath.  The  contraction  of  the  vessels  is 
probably  due  in  part  to  a  reflex  and  in  part  to  the  direct  stimulus  of  the  cold 
water.  Observations  upon  the  rate  of  the  pulse  are  very  discordant,  some 
authors  stating  that  it  is  quickened,  others  that  no  alteration  takes  place,  and 
others  that  it  is  slowed.  The  explanation  of  these  discrepancies  is  that  at  first 
the  pulse  is  slightly  accelerated,  but  subsequently  it  is  retarded.  The  primary 
quickening  is  often  but  slight,  or  it  may  be  unobservable  ;  probably  it  is  due 
to  the  rise  in  the  blood-pressure  caused  by  the  contraction  of  the  cutaneous 
vessels.  The  exact  temperature  necessary  to  cause  a  marked  slowing  is  not 
the  same  for  all  persons.  Kirejeff  could  not  detect  any  effect  upon  the  pulse 
after  a  bath  of  71°"6  to  75°'2  F.,  but  Kemig  found  that  a  regular  diminution 
of  pulse-rate  was  produced  by  baths  of  a  temperature  of  95°  F.,  and  Draper 
found  after  a  cold  bath  lasting  an  hour  and  composed  of  water  at  a  temperature 
of  74°  F.  that  there  was  considerable  slowing  of  the  pulse,  which  retardation 
remained  for  some  little  time  after  the  cessation  of  the  bath.  Probably  the 
blood-pressure  rises  a  little  when  the  cutaneous  vessels  are  contracted  by  the 
cold  bath  and  falls  when  they  are  paralytically  dilated,  but  we  have  no 
experiments  in  proof  of  this. 

With  regard  to  respiration,  the  first  effect  of  a  cold  bath  is  that  the 


BATHS  623 

bather,  if  the  water  be  sufficiently  cold,  gasps  and  experiences  a  sensation 
of  difficulty  of  breathing.  At  the  same  time  he  feels  a  shiver  run  all  over 
him.  This  is  accompanied  by  a  long-drawn  inspiration  which  may  deepen 
into  a  sigh.  Then  there  is  a  sudden  stoppage  in  respiration,  due  in  part  to  a 
spasmodic  closure  of  the  glottis.  This,  however,  soon  passes  off  and  there  is 
a  prolonged  expiration  and,  in  extreme  cases,  a  groan.  With  healthy  persons 
it  takes  a  considerable  degree  of  cold  to  produce  these  effects,  which  are  wit- 
nessed after  much  less  cold  in  children  and  sickly  people.  The  frequency  of 
the  respirations  is  at  first  a  little  greater,  but  soon  they  are  considerably 
slowed.  This  is  true  both  of  man  and  animals.  Leichtenstern  says  that  all 
observations  agree  that  the  amount  of  air  respired  increases  in  a  cold  bath. 
In  one  of  his  experiments  a  rabbit  was  immersed  in  water  at  a  temperature 
of  53°"6  F.  During  a  bath  of  fifteen  minutes  the  volume  of  air  breathed 
was  increased  25  per  cent.  It  is  clear  that  if  the  number  of  respirations  is 
diminished  their  depth  must  be  enormously  increased. 

After  a  little  while  the  condition  of  goose-skin  is  seen  ;  this  is  probably 
due  to  a  contraction  of  the  arrectores  pili, 

Weber  has  shown  that  very  cold  baths  diminish  the  cutaneous  sensi- 
bility. This,  however,  does  not  apply  if  the  stimulus  be  a  warm  substance, 
for  the  colder  the  skin  the  greater  is  its  power  of  distinguishing  warm  bodies 
when  they  are  applied  to  it.  If,  however,  the  degree  of  cold  be  moderate, 
cutaneous  sensibility  is  at  first  raised,  and  stimuli  which  ordinarily  could 
hardly  be  felt  are  painful.  The  property  possessed  by  cold  water  of  stimu- 
lating the  peripheral  nerves  is  frequently  used  to  accelerate  the  return  of  con- 
sciousness in  persons  who  have  fainted.  After  a  cold  bath  of  short  duration 
there  is,  as  is  well  known,  a  feeling  of  well-being  and  exhilaration.  The 
bather  is  refreshed.  The  mental  faculties  are  cleared,  the  muscles  seem 
strengthened,  and  there  is  a  desire  for  both  muscular  and  mental  work. 

If  the  bath  be  very  cold,  or  the  bather  stop  in  it  a  long  while,  the  bladder 
and  rectum  may  be  emptied  reflexly  and  he  may  experience  partial  paralysis 
of  the  muscles  of  the  body,  together  with  a  general  sense  of  weariness  and 
mental  weakness. 

The  feehng  of  well-being  which  follows  a  short  bath  is  usually  explained 
by  the  fact  that,  owing  to  the  contraction  of  the  cutaneous  vessels,  there 
will  be  more  blood  in  the  internal  organs  and  consequently  a  more  rapid 
removal  of  waste-products  from  them,  and  an  increased  stimulus  to  their 
functional  activity.  On  the  other  hand,  if  the  cold  be  sufficiently  prolonged 
to  paralytically  dilate  the  cutaneous  vessels  it  is  obvious  that,  owing  to  there 
being  less  blood  in  muscles  and  other  internal  organs,  waste-products  will 
accumulate  in  them,  and  the  amount  of  blood  in  them  will  be  diminished. 
The  feeling  of  warmth  after  leaving  the  bath  is  to  be  attributed  to  tbe  re- 
actionary dilatation  of  the  cutaneous  vessels,  which  is  subsequent  to  their 
contraction.  If  there  is  no  feeling  of  warmth  it  may  be  that  either  the 
vessels  of  the  skin  have  not  contracted,  or  that  they  have  dilated  because  they 
are  paralysed  by  the  cold,  or  that,  having  contracted,  they  will  not  expand 
again  on  leaving  the  bath.  There  are  many  individual  peculiarities  in  these 
respects.  Bathers  must  always  be  careful  not  to  take  a  bath  so  prolonged, 
or  of  a  temperature  so  low,  as  to  prevent  the  reactionary  dilatation  of  tlie 
cutaneous  vessels.  A  patient  feels  the  after-effects  of  a  cold  bath  more  if  he 
has  just  had  a  hot  one  and  vice  versa. 

Cold  baths  are  largely  used  for  the  exhilaration  that  ensues,  which  can  be 
increased  by  rubbing  with  a  rough  towel.  If  they  are  taken  constantly,  the 
alternate  contraction  and  relaxation  of  the  vessels  train  them  to  contract 
easily,  and  therefore  habitual  bathers  are  not  very  liable  to  catch  cold. 


02-1  HYGIENE 

We  v;ill  now  discuss  some  of  the  more  important  effects  of  the  local  ap- 
plication of  cold  water  by  means  of  local  baths,  douches,  sprays,  &c.  Our 
most  accurate  information  on  this  subject  is  due  to  the  labours  of  Winternitz. 
He  used  the  plethysmograph  and  showed  that  when  cold  was  locally  applied 
to  any  part — for  example,  the  middle  of  the  arm — there  was  a  diminution  in 
the  size  of  the  vessels,  of  the  quantity  of  blood,  and  a  lowering  of  temperature 
in  the  parts  beyond  the  point  of  application,  and  the  reverse  in  the  parts 
behind.  One  of  "Winternitz's  figures  showing  the  great  diminution  in  the 
size  of  the  radial  pulse-wave  after  the  application  of  cold  to  the  arm  is  very 
striking.  Its  amplitude  is  diminished  by  quite  three-quarters.  Other  figures 
of  plethysmographic  tracings  show  most  markedly  the  diminution  in  the  size 
of  the  arm  produced  by  immersion  in  cold  water.  When  the  area  of  the  body 
to  which  the  cold  is  applied  is  considerable,  the  local  vascular  contraction  is 
accompanied  by  a  universal  dilatation  of  the  vessels  all  over  the  rest  of  the 
body.  This  fact  Winternitz  has  proved  with  the  plethysmograph,  by  which 
instrument  he  obtained  a  tracing  which  showed  most  markedly  the  increased 
volume  of  the  arm  due  to  a  sitz  bath  at  a  temperature  of  4G°*4  F.  The  tem- 
perature of  the  axilla  was  at  the  same  time  raised. 

The  local  application  of  cold  has  another  important  efl'ect,  namely,  that 
it  produces  a  reflex  contraction  of  distant  vessels.  Naumann  separated  all 
the  parts  of  the  posterior  extremity  of  a  frog  so  that  the  limb  remained  at- 
tached to  the  body  only  by  the  sciatic  nerve.  He  then  applied  cold  to  the 
leg,  and  observed  that  if  the  cold  were  moderate  there  was  a  diminution  in 
the  capillary  circulation  of  the  mesentery,  but  when  the  apphcation  of  cold 
was  prolonged  there  was  a  dilatation  of  the  vessels.  SchuUer,  in  the  same 
way,  showed  that  the  application  of  a  moderate  degree  of  cold  caused  contrac- 
tion of  the  vessels  of  the  pia  mater ;  the  application  of  an  extreme  degree 
caused  dilatation  of  the  same  vessels.  Franck,  working  with  the  plethysmo- 
graph, showed  that  the  application  of  cold  water  to  one  hand  produced  a  de- 
crease in  the  size  of  the  vessels  of  the  other.  These  experiments  have  been 
confirmed  by  Mosso.  All  these  effects  are  undoubtedly  reflex,  and  some  ex- 
periments of  Winternitz  are  very  interesting  as  showing  an  association  be- 
tween different  parts  of  the  body.  Thus  he  found  that  the  application  of 
cold  to  the  feet  influences  chiefly  the  intra-cranial  circulation,  cold  to  the 
thighs  affected  chiefly  the  pulmonary  circulation,  and  cold  to  the  back  especi- 
ally influences  the  circulation  of  the  vessels  of  the  nose.  This  fact  is  very 
interesting  in  connection  with  the  popular  practice  of  putting  a  cold  key  down 
the  back  for  epistaxis.  These  reflex  effects  of  cold  applied  to  the  skin  in 
contracting  deeply  placed  vessels  have  many  applications  in  medicine  :  thus 
we  apply  an  ice-bag  to  the  head  for  concussion,  and  ice-poultices  to  the  chest 
for  pneumonia.  Some  find  a  cold  sitz  bath  useful  for  diarrhoea.  Another 
reflex  effect  of  the  local  application  of  cold  to  the  skin  is  that  at  first  the 
pulse  and  respiration  are  increased  in  frequency,  afterwards  they  diminish. 
If  the  cold  be  very  severe  there  may  be  much  palpitation  and  gasping. 

Cold  feet  can  be  warmed  by  the  reaction  after  a  cold  foot  bath,  and  men- 
struation can  in  some  women  be  checked  by  the  same  means.  The  many 
applications  of  cold  for  various  medicinal  purposes,  chiefly  to  reduce  in- 
flammation, hardly  come  within  the  scope  of  the  present  article.  It  is  said 
that  cold  baths  increase  the  number  of  the  red  blood-corpuscles  and  the 
amount  of  haemoglobin  in  them,  and  for  this  reason  some  advise  cold  baths 
for  anaemia. 

Cold  baths  are  contra-indicated  in  all  who  do  not  react  rapidly  after  them. 
Therefore  they  should  not  be  ordered  for  the  very  young,  the  very  old,  or 
those  debilitated  by  disease,  nor  for  those  in  whom  there  is  already  congestion 


BATES  625 

of  the  internal  organs,  unless  it  be  with  the  object  of  producing  a  reflex  local 
efifect.  All  baths,  save  those  which  are  temperate,  are  forbidden  for  persons 
with  disease  of  the  heart. 

Warm  Baths 

It  is  usually  supposed  that  the  temperature  of  the  human  body  remains  con- 
stant even  if  the  variations  of  that  of  the  surrounding  medium  are  extreme. 
But  we  usually  forget  the  important  influence  exercised  by  our  clothes  in 
maintaining  the  average  temperature  of  the  body.  It  has  been  undoubtedly 
shown  that,  if  we  consider  the  naked  body,  its  temperature  is  constant  only 
within  certain  narrow  limits.  To  speak  more  accurately,  we  ought  to  say  the 
temperature  of  the  folds  of  the  skin,  for  most  of  the  observations  have 
reference  only  to  the  axillary  temperature.  Senator  observed  the  effect  of 
undressing  in  a  room  and  found  that  it  reduced  the  axillary  temperature 
slightly,  even  when  the  room  was  of  the  usual  temperature  of  60°  F.  or 
between  58°  and  70°  F.,  and  he  comes  to  the  conclusion  that  the  axillary 
temperature  is  only  constant  if  the  body  is  naked  when  the  surrounding  tem- 
perature does  not  differ  more  than  from  14°  to  18°  F.  from  that  of  the  body. 
Winternitz  has  performed  a  number  of  experiments  and  has  shown  that 
alterations  in  the  temperature  of  the  air  only  affect  the  temperature  inside 
the  clothes  slightly,  unless  the  alteration  be  about  50°  F.,  so  that,  although 
in  ordinary  life  man's  temperature  is  constant,  that  is  due  not  -only  to  the 
adjustment  of  it  but  also  to  the  fact  that  the  temperature  next  to  his  skin  is 
fairly  constant.  We  have  already  seen  that  a  cold  bath  will  alter  the  tempera- 
ture of  the  body,  and  from  what  one  has  just  learnt  we  are  not  surprised  to 
find  that  a  warm  bath  will  do  the  same. 

A  warm  bath,  therefore,  increases  the  temperature  of  the  body  both  by 
imparting  heat  to  it  and  preventing  the  loss  of  warmth  from  it.  Zuntz  and 
Eohrig  put  a  dog  for  eighteen  minutes  in  a  bath  at  107°  F. ;  the  animal's 
temperature  rose  4°  F.  ;  and  Seiche  and  Schmelkes  have  obtained  similar 
results.  Liebermeister  found  that  if  the  water  of  the  bath  was  at  the  tem- 
perature of  the  body,  so  that  no  heat  was  given  off,  the  temperature  in  the 
axilla  rose.  Thus,  in  one  experiment,  in  55  min.  the  temperature  rose  from 
99°"5  to  102°  F.,  and  in  another  similar  experiment  it  rose  from  99°  F.  to 
102°-4F.  Hosier  observed  in  hot  baths  of  104°  to  111°-2F.  that  the  tem- 
perature of  the  mouth  would  rise  to  101°*6F.  After  the  bath  is  over  the 
temperature  gradually  falls  again.  It  may  be  urged  that  in  Turkish  and 
Eussian  baths  the  temperature  of  the  body  does  not  rise  in  anything  like 
the  proportion  of  that  the  above  figures  indicate,  but  it  must  be  remembered 
that  a  hot-water  bath  prevents  loss  of  heat  from  the  body  almost  completely, 
for  there  can  be  no  loss  by  evaporation,  none  by  conduction,  and  very  little, 
if  any,  by  radiation.  In  a  vapour  bath,  unless  the  air  is  saturated,  evapora- 
tion of  the  sweat  from  the  skin-evaporation  can  take  place.  Still,  the  tem- 
perature of  the  body  does  rise  considerably  in  a  vapour  bath.  Bartels  gives 
an  experiment  in  which  in  a  vapour  bath  of  127°*4  F.  the  temperature  of 
the  body  rose  in  10  min.  from  100° -4  to  104°-5  F.  On  another  occasion,  in 
a  vapour  bath  of  123°'8  F.  the  temperature  of  the  same  individual  rose  from 
100°-4  in  8  min.  to  103°  F.  in  30  min.  to  107°  F.  Many  other  observers  have 
published  results  which  accord  with  these.  In  a  Turkish  bath  the  tempera- 
ture of  the  body  may  rise  a  little  in  the  hotter  rooms,  but  owing  to  the  rapid 
evaporation  of  the  sweat  the  rise  is  very  slight.  Kemig  has  attempted  to 
find  out  whether  there  is  any  alteration  in  the  production  of  heat  in  a  patient 
taking  a  hot  bath,  but  the  experiments  are  not  sufficiently  accurate  and  we 
have  no  evidence  on  the  matter.  The  exhalation  of  carbon  dioxide  and  water 
VOL.  I.  s  s 


G2G  HYGIENE 

from  the  lungs  is  increased,  but  because  that  of  the  oxygen  is  diminished  the 
total  quantity  of  respired  air  is  lessened.  According  to  Braun,  if  a  warm  bath 
be  very  long  continued  the  blood  becomes  thick  and  dark-coloured  and  there 
is  a  continuance  of  the  greater  oxidation  at  the  expense  of  both  the  blood  and 
the  tissues.  ^Yinteruitz  states  that  the  changes  in  the  urea  are  the  same  in 
both  hot-water  and  vapour  baths,  but  that  the  increase  in  the  excretion  of  it 
in  water  baths  is  less  than  it  is  in  vapour  baths.  Naunyn  found  that  in  dogs 
whose  temperature  had  been  artificially  raised  the  amount  of  urea  excreted 
was  augmented,  and  Bartels  observed  that  in  men  who  took  warm  baths  the 
amount  of  urea  was  increased.  Schleich  made  a  most  careful  series  of  ex- 
periments in  which  a  uniform  diet  was  maintained  througliout.  On  certain 
days  the  temperature  was  raised  to  103°  F.  by  means  of  hot  baths  :  on  these 
days  there  was  always  an  increase  in  the  urea  excreted  ;  this  continued  for 
some  days  after  the  bath,  but  gradually  decreased,  and  at  last  was  succeeded 
by  a  compensatory  decrease  of  urea. 

It  is  said  that  there  is  an  immediate  momentary  fall  of  the  pulse  in  the 
hot  bath ;  but  this  is  very  quickly  followed  by  an  acceleration.  In  one  of 
Kemig's  experiments  a  bath  at  99°  F.  caused  a  rise  in  the  pulse  from  80  to 
96  beats,  but  a  cold  shower  bath  brought  it  down  rapidly  to  about  74.  The 
rise  in  the  rate  of  the  pulse  is  always  proportionate  to  the  rise  in  the  bodily 
temperature.  Owing  to  the  wide  dilatation  of  the  cutaneous  vessels  there  is 
a  fall  in  the  blood-pressure  of  internal  organs. 

Many  experiments  have  been  made  with  regard  to  the  influence  of  warm 
baths  upon  respiration,  and,  although  some  of  them  are  discordant,  all  the 
more  accurate  show  that  the  respirations  increase  in  frequency  proportion- 
ately to  the  rise  in  the  temperature  of  the  body.  This  is  true  not  only  of 
hot-water  baths  but  also  of  hot-air  and  vapour  baths. 

After  leaving  the  bath  the  skin  is  red  and  the  secretion  of  sweat  is 
enormously  increased.  Hot  water  liquefies  the  fatty  secretions  of  the  skin, 
and  is  a  better  solvent  than  cold  ;  therefore  it  cleanses  the  body  more 
thoroughly. 

After  a  hot  bath  the  secretion  of  urine  is  lessened,  just  as  after  a  cold  bath 
it  is  increased.  In  certain  cases  it  is  said  to  be  slightly  increased  for  a  short 
time  after  even  a  warm  bath,  but  it  is  doubtful  whether  in  such  cases  there 
is  really  an  increase  in  the  secretion  ;  probably  the  general  muscular  relaxa- 
tion produced  by  the  warm  bath  gives  rise  to  a  desire  to  void  the  urine. 
Koloman  Milller  counted  the  drops  of  urine  leaving  the  ureter  from  shaved 
dogs.  When  the  dog  was  put  in  water  at  104°  F.  the  secretion  of  urine 
was  decreased ;  but  under  the  mfluence  of  cold  water  it  was  increased  by  from 
5  to  11  drops  in  each  five  minutes.  It  is  said  that  after  a  prolonged  warm 
bath  the  uruie  is  rendered  alkaline,  but  Leichtenstern  and  Eohrig  deny  this. 
The  following  summary  of  the  chief  effects  of  warm  baths  is  taken  from  the 
writer's  '  Text-book  of  General  Therapeutics.' 

Owing  to  the  dilatation  of  the  cutaneous  vessels  blood  is  withdrawn  from 
the  internal  organs,  and  thereby  their  functional  activity  is  depressed.  This 
explains  many  uses  of  hot  baths  ;  one  taken  immediately  before  going  to  bed 
has  long  been  known  to  be  a  valuable  remedy  for  insomnia.  The  soporific 
effect  of  a  warm  bath  has  been  Imown  to  cause  the  death  of  the  bather. 
Frequent  warm  baths  are  enervating.  Great  weariness  of  the  muscles  is 
reheved  by  a  hot  bath,  probably  because  by  withdrawing  blood  from  them  it 
lowers  the  activity  of  the  processes  going  on  in  them.  Napoleon,  if  possible, 
always  took  one  when  he  was  unable  to  get  a  night's  rest.  Braun  lays 
considerable  stress  on  the  chemical  changes  in  the  tissues  and  the  blood 
that  the  rise  of  temperature  produces,  and  some  authors  believe  warm  baths 


BATHS  G27 

to  have  an  absorbing  power  over  inflammatory  products,  but  these  matters 
are  very  difficult  of  proof. 

The  effects  are  often  not  the  same  on  different  individuals,  but  for  nearly 
all  persons  the  following  propositions  are  true  : — 

Hot  baths,  like  any  other  application  of  heat,  soothe  pain  ;  hence  they  are 
useful  for  rheumatoid  anthritis  and  colic,  whether  it  be  renal,  biliary,  or 
intestinal.  By  bringing  blood  to  the  skin  and  lessening  the  amount  in  the 
internal  organs  they  relieve  muscular  spasm  such  as  we  find  in  stricture  of 
the  urethra,  colic,  laryngismus  stridulus,  other  forms  of  laryngeal  spasm,  and 
infantile  convulsions.  In  the  same  way  they  are  of  service  in  weariness  from 
muscular  or  cerebral  activity,  are  soporific,  and  are  useful  in  many  inflam- 
matory affections,  as  a  cold,  in  the  head.  The  subsequent  increased  perspira- 
tion makes  them  of  great  value  in  the  various  forms  of  nephritis  and  in 
anemia.  Great  care  must  be  taken  after  a  hot  bath  which  has  been  given 
to  induce  sweating  to  see  that  the  patient  is  kept  warm  by  being  wrapped 
quickly  in  a  hot  blanket  and  being  put  into  a  warm  bed.  If  not,  the  cuta- 
neous vessels  soon  contract,  all  the  good  of  the  bath  is  undone,  and  there 
is  no  diaphoresis. 

The  same  names  are  applied  to  local  baths  whether  they  are  hot  or  cold. 

We  have  seen  that  the  local  application  of  cold  to  a  part  causes  contrac- 
tion of  the  vessels  and  lowering  of  the  temperature  ;  in  the  same  way  the 
local  warm  bath  causes  a  great  dilatation  of  the  superficial  vessels  of  the  part 
and  a  local  rise  of  the  temperature  of  the  skin.  As  a  result  of  this  dilatation 
blood  is  withdrawn  from  distant  parts,  the  size  of  the  part  to  which  the  heat 
is  applied  is  increased,  and  when  the  warmth  is  withdrawn  a  copious  local 
perspiration  takes  place.  Often  as  with  cold  so  with  heat,  a  reflex  effect  upon 
the  vessels  of  some  deep-seated  organ  occurs.  This  is  due  to  the  stimula- 
tion of  the  skin  by  the  heat.  For  example,  upon  the  application  of  warmth 
to  the  chest  not  only  the  cutaneous  vessels  of  the  chest-wall  but  those  of  the 
lungs  and  pleura  immediately  underneath  the  point  of  application,  dilate. 
The  local  hot  baths  most  frequently  used  are  the  foot  bath,  which  is  very 
•often  used  to  withdraw  blood  to  the  lower  extremities  in  a  case  of  cold  in  the 
nose  ;  and  the  sitz  bath,  which  leads  to  dilatation  of  the  pelvic  vessels  and 
may,  therefore,  be  used  in  amenorrhcea.  A  mustard  bath  is  a  local  hot  bath 
to  which  from  one  to  three  ounces  of  mustard  have  been  added  to  every 
-fifteen  gallons  of  water. 

The  Physiological  Action  of  the  Constituents  op  the  Bath 

There  has  for  several  years  been  a  long  and  heated  controversy  as  to 
whether  the  constituents  of  a  bath  are  absorbed  by  the  skin. 

Many  have  attempted  to  determine  whether  water  was  absorbed  by  the 
skin.  Some  weighed  the  bather  before  and  after  the  bath,  others  weighed  the 
water.  Some  concluded  that  the  body  gained  in  weight  from  the  absorption 
■of  water,  others  thought  it  lost  weight  in  a  bath,  and  others  again  could  detect 
no  difference  whatever.  Observers  have  been  even  known  to  declare  that  a 
bath  increased  the  weight  of  the  bather  by  pounds.  In  all  these  experi- 
ments the  most  obvious  fallacies — such  as  the  evaporation  of  water,  the 
failure  to  dry  the  bather  completely,  and  many  others — were  not  guarded 
against,  and  the  whole  of  the  experiments  are,  therefore,  perfectly  valueless. 
Krause  made  a  series  of  experiments  upon  the  power  of  pieces  of  dead  skin 
to  imbibe  water,  and  because  he  found  that,  after  a  long  time,  it  could  absorb 
water,  certain  people  have  jumped  to  the  conclusion  that  the  skin  absorbs 
water  in  a  bath,  quite  forgetting  the  fact  that  Krause  experimented  with 

ss2 


C28  HYGIENE 

pieces  of  dead  skin.  Imbibition  by  the  skin  Avas  tliouglit  also  to  be  proved 
by  the  fact  that  if  the  arm  were  placed  in  a  vessel  containing-  some  salt  in 
solution  and  then  in  plain  water,  the  latter  was  found  to  contain  some  of  the- 
salt,  but  no  allowance  was  made  for  the  fact  that  some  of  the  salt  might  have 
adhered  to  the  hairs  on  the  arm.  Lastly,  we  need  hardly  point  out  that  an 
increased  flow  of  urine  after  a  bath  is  not,  as  some  would  have  us  believe, 
any  evidence  whatever  that  water  has  been  absorbed,  for  the  variations  in  the 
vasomotor  condition  of  the  skin  are  quite  enough  to  account  for  it.  There- 
fore, we  may  conclude  that  tliere  is  no  evidence  that  the  skin  can  absorb 
water  from  a.  bath  ;  indeed,  when  we  remember  the  oily  condition  of  the 
epidermis,  covered  as  it  is  by  sebaceous  secretion,  we  should  hardly  expect 
that  it  could  take  up  any  water. 

Multitudes  of  experiments  have  been  made  with  the  object  of  showing 
that  any  salts  which  are  dissolved  in  the  water  are  taken  up  by  the  skin. 
The  salt  most  frequently  used  has  been  chloride  of  sodium.  Beneke  and 
Eohrig  have  shown  most  conclusively  that  this  is  not  absorbed.  The  latter 
observer  carefully  estimated  the  amount  of  chloride  of  sodium  excreted  by  a 
patient  and  then  he  gave  a  salt  bath,  of  a  temperature  of  95°  F.,  but  could 
detect  no  increase  in  the  amount  of  the  salt  in  the  urine. 

Many  experiments  have  been  made  with  salts  of  iron  ;  the  most  satisfac- 
tory are  those  in  which  ferrocyanide  of  potassium  was  used,  and  all  these 
show  that  salts  of  iron  are  not  capable  of  absorption  by  the  skin.  Experi- 
ments with  salts  of  lithium  likewise  gave  negative  results.  Iodide  of  potas- 
sium is  a  favourite  salt  for  experimentation,  as  it  is  very  diffusible ;  many 
experiments  appear  to  show  that  this  can  be  absorbed  by  the  skin,  but  no- 
guard  has  been  made  against  the  fallacy  that  it  is  very  liable  to  be  decom- 
posed in  the  bath  and  that  the  free  iodine  thus  given  off,  being  volatile,  may 
be  taken  up  by  the  lungs.  The  amount  that  it  has  been  supposed  the  skin 
might  take  up  is  not  greater  than  may  be  accounted  for  in  this  Avay.  Some 
observers  have  put  powerful  drugs,  such  as  opium,  belladonna,  digitalis,  cor- 
rosive sublimate,  into  the  water,  and  have  endeavoured,  by  observing  whether 
the  patient  was  affected  by  them,  to  determine  if  they  were  absorbed  by  the 
skin  ;  but  all  these  experiments  were  so  carelessly  conducted  that  they  are 
valueless.  If,  therefore,  we  exclude  substances  which  might  have  a  powerful 
chemical  influence  on  the  skin,  and  also  those  which  are  volatile  and  might, 
therefore,  be  absorbed  by  the  lungs,  we  see  there  is  no  evidence  whatever  that 
the  skin  has  any  power  of  absorbing  substances  which  are  dissolved  in  baths. 

Chrzonsczewsky  has  made  some  experiments  which  are  so  often  quoted 
that  we  must  just  refer  to  them.  He  shaved  parts  of  animals  and  immersed 
the  shaved  parts  in  baths  containing  various  substances  in  solution.  The 
water  of  the  bath  was  covered  with  oil  to  prevent  evaporation.  According  to 
Chrzonsczewsky,  large  quantities  were  absorbed,  but  we  are  not  told  whether 
the  animals  were  scratched  or  cut  during  the  shaving,  and  the  symptoms 
produced  were  so  severe  that  there  is  clearly  an  error  somewhere.  There  is 
no  doubt  that  the  skin  can  absorb  small  quantities  of  volatile  bodies  such  as 
iodine,  but  even  in  these  cases  the  amount  absorbed  by  the  lungs  is  probably 
much  greater.  Of  course  it  is  well  known  that  some  substances,  such  as 
mercury,  can  be  absorbed  by  the  skin  if  they  are  rubbed  in  thoroughly. 

The  skin  appears  to  absorb  small  quantities  of  certain  gases  that  are 
dissolved  in  the  water  of  a  bath,  but,  as  just  mentioned,  this  is  probably  to 
be  entirely  explained  by  the  fact  that  some  of  the  gas  is  given  off  from  the 
bath  and  is  taken  up  by  the  lungs  and  such  of  the  skin  as  is  not  under  water. 
Chloroform,  ether,  hydrocyanic  acid,  carbon  dioxide,  carbonic  oxide,  and 
sulphur  dioxide  are  instances  of  gas  that  can  be  absorbed  in  this  way.     The 


BATHS  G29 

amount  which  can  be  taken  up  by  the  sldn  is  so  small,  in  comparison  with 
the  quantity  that  can  be  taken  up  by  the  lungs,  that  inhalation  is  always  to 
be  preferred  to  cutaneous  absorption. 

It  has  been  repeatedly  stated  that  baths  with  a  salt  or  gas  in  them  have  a 
•stimulating  effect  upon  the  skin.  This  is,  however,  very  slight — so  slight 
indeed  that  Leichteustern  considers  that  its  only  effect  is,  to  a  small  extent, 
to  influence  the  vasomotor  effect  of  baths,  so  that  the  vascular  dilatation 
after  a  cold  bath,  and  the  vascular  dilatation  in  a  warm  bath,  are  a  little  in- 
creased if  the  bath  contain  a  salt  or  gas  in  solution  ;  but  he  goes  on  to  say 
that  this  stimulating  effect  of  the  salt  or  gas  is  too  small  to  influence  the 
frequency  or  depth  of  the  respiration,  or  to  modify  the  quantity  of  urine 
passed  after  the  bath,  or  to  influence  the  quantity^of  urea  and  carbon  dioxide 
■excreted,  or  to  alter  the  temperature  of  the  body  or  the  pulse-rate.  In  fact, 
the  influence  of  the  gas  or  salt  dissolved  in  the  water  is  so  slight  that  it  may 
be  totally  disregarded,  and  baths  act  chiefly  by  their  temperature. 

We  have  seen  that  no  absorption  takes  place  in  a  bath  ;  nevertheless,  it  is 
probable  that  the  superficial  layers  of  the  epidermis  can  to  a  slight  extent 
imbibe  water,  although  so  little  is  thus  taken  up  that  the  effects  of  the  imbi- 
bition are  inappreciable. 

Leichtenstern  calculates  that  probably  500  to  600  kilogrammes  are  in  an 
ordinary  bath  added  to  the  atmospheric  pressure  of  15,450  kilogrammes  on 
the  whole  body.  We,  however,  know  nothing  of  any  effects  which  can  be 
attributed  to  this  action. 

The  electrical  operations  of  a  bath  are  involved  in  much  obscurity. 
Heymann  and  Krebs  appear  to  be  the  most  careful  of  those  who  have  experi- 
mented upon  this  subject.  They  found  that  all  the  mineral  and  gas  contain- 
ing waters,  with  the  exception  of  sulphur  ones,  act  positively  when  brought 
in  contact  with  distilled  water  ;  that  the  highest  degree  of  electrical  relation 
was  caused  by  the  presence  of  the  gases  in  the  water,  the  next  degree  by  the 
temperature  of  the  water,  and  the  third  degree  by  the  presence  of  salts. 
The  gases  experimented  upon  were  carbon  dioxide,  nitrogen,  oxygen,  and 
sulphuretted  hydrogen.  The  alterations  due  to  temperature  were  to  be 
attributed  to  variations  in  the  conductivity  of  the  water.  The  gases  contained 
in  water  (except  sulphuretted  hydrogen)  are  the  cause  of  their  electro-positive 
behaviour,  for  distilled  water  containing  neutral  or  basic  salts  is  towards 
plain  distilled  water  not  electro-positive  but  electro-negative.  The  only  infor- 
mation we  have  upon  the  electrical  reactions  of  the  human  body  when  in 
water  is  derived  from  an  experiment  of  Heymann's.  A  man  was  put  into  a 
bath.  One  pole  was  placed  in  the  bath  water  and  the  other  on  the  man's 
skin  outside  the  bath.  Ordinary  water,  and  water  containing  carbon  dioxide, 
were  both  of  them  positive,  wliile  the  body  was  negative ;  but  if  sulphu- 
retted hydrogen  was  dissolved  in  the  water  this  was  negative  and  the  body 
positive.  It  is  not  known  whether  these  electrical  variations  have  any  effect 
iipon  the  human  body,  nor  is  any  use  of  them  made  in  medicine.  It  is 
quite  needless  to  refer  to  the  large  amount  of  rubbish  that  has  been  written 
on  the  subject  of  the  electrical  reactions  of  baths. 


THE   USES   OP  BATHS   CONSIDEEED   ACCOEDING  TO   THEIE 
TEMPEEATUEE 

We  will  now  pass  on  to  the  consideration  of  the  uses  of  baths,  and  in  so 
-doing  we  shall  omit  many  of  the  applications  which  most  writers  on  balneo- 
logy describe.     There  is  probably  no  disease  for  which  baths  have  not  been 


630  HYGIENE 

recommended,  but  frequently  those  who  advocate  some  particular  form  of 
bath  are  pecuniarily  interested  m  bathing-establishments,  and  a  little  exami- 
nation shows  that  the  bath  cannot  possibly  have  the  beneficial  effects  at- 
tributed to  it.  The  uses  of  special  kinds  of  baths  will  be  described  mider 
separate  headings. 

Uses  of  Indifpeeent  Baths 

Baths  in  which  the  bather  feels  neither  hot  nor  cold  are  used  for  cleansing 
purposes  and  also  for  the  mild  exhilarating  eti'ects  that  the  bather  feels  on 
leaving  them,  when  he  has  rubbed  himself  quickly  with  a  rough  towel.  No 
time  should  be  lost  between  the  exit  from  the  bath  and  the  drying,  whether 
the  bath  be  warm,  cold,  or  indifferent,  for  the  evaporation  of  the  water  from 
the  skin  will  cool  the  body.  Directly  after  drying,  the  clothes  should  be 
put  on.  No  bath,  whatever  its  temperature,  should  be  taken  immediately 
after  a  meal.  It  is  said  that  indifferent  baths  will  cure  mild  functional 
nervous  diseases,  such  as  slight  cases  of  hysteria.  Unfortunately,  many 
authors  apply  the  term  '  indifferent  thermal  waters '  to  warm  baths  not  con- 
taining any  important  mineral  constituent. 


Uses  of  Cool  or  Cold  Baths 

The  temperature  of  the  water  which  can  be  used  for  baths  varies  im- 
mensely for  different  people,  but  everyone  can  easily  find  for  himself  the 
temperature  which  suits  him  best.  It  must  never  be  so  low  as  to  prevent 
the  reactionary  dilatation  of  the  cutaneous  vessels  which  ought  to  succeed 
after  a  bath.  For  the  same  reason  a  cold  bath  must  never  be  prolonged. 
Directly  upon  leaving  the  bath  the  bather  must  rub  himself  thoroughly  and 
quickly  with  a  rough  towel  to  aid  the  cutaneous  vascular  dilatation,  and  it  is- 
particularly  important  that,  in  order  to  prevent  any  loss  of  heat,  he  should 
dress  quickly.  We  have  already  seen  that  after  a  cold  bath  there  is  a  feeling 
of  exhilaration  and  warmth,  the  energy  appears  to  be  increased  and  the 
mental  faculties  quickened.  It  is  for  these  effects  that  a  cold  bath  on  getting 
up  in  the  morning  forms  part  of  the, daily  life  of  so  many  Englishmen.- 
Persons  accustomed  to  cold  baths  are  less  liable  to  catch  cold  than  those 
who  do  not  use  them.  Apart  from  their  antipyretic  effect,  cold  baths  are 
chiefly  used  for  their  stimulating  effect.  There  are  many  hydropathic 
establishments  with  admirable  cold  baths,  and  Avhere  all  the  accessories, 
such  as  rest,  fresh  air,  and  regular  meals,  aid  the  hydrotherapeutic  treat- 
ment. Patients  sufl'ering  from  general  exhaustion,  due  mostly  to  mental 
overwork,  strain  and  anxiety,  are  often  conspicuously  benefited  by  a  stay  at  a 
hydropathic  establishment.  Very  often  patients  of  this  class  suffer  from, 
chronic  indigestion,  which  is  frequently  alleviated  by  a  visit  to  one  of  these 
places  ;  therefore,  when  the  two  conditions  are  combined,  such  treatment  is 
particularly  suitable.  Certain  cases  of  hypochondriasis  and  hysteria  are 
sometimes  brilliantly  cured,  but  in  others  no  good  whatever  results.  We 
have  already  indicated  the  principles  which  should  guide  us  in  the  local 
application  of  cold.  Cold  hip  baths  have  been  found  useful  m  impotence, 
spermatorrhoea,  amenorrhoea,  and  prostatitis.  The  cold  douche  is  largely 
used  as  a  local  stimulant,  and  will  reflexly  affect  the  circulation  in  the  organs 
under  the  point  of  application. 

The  places  best  known  for  their  cold  baths  are  Ilkley,  Ben  Ehydding, 
Malvern,  Wemyss  Bay,  Forres,  Crieff,  Nassau,  Boppard,  Godesberg,  Wies- 
baden, Alexandersbad,  Liebenstein,  and  Rigi  Kaltbad. 


BATHS  631 

The  Antipyretic  Uses  of  the  Gold  Bath. — The  use  of  the  cold  bath  in 
fever  has,  during  the  last  twenty-five  years,  revolutionised  our  ideas  con- 
cerning the  treatment  of  febrile  disorders.  It  is  a  very  wide  subject,  and 
therefore  in  an  article  of  this  nature  only  a  brief  account  of  it  can  be  given. 
Fuller  information  may  be  found  in  Liebermeister's  '  Antipyretics ;  '  Von 
Ziemssen's  '  Handbook  of  General  Therapeutics,'  vol.  ii.  Eng.  Trans. 
1885-6 ;  Currie's  '  Medical  Eeports  on  the  Effects  of  Water,  Cold  and 
Warm,  as  a  Eemedy  in  Fever  and  Febrile  Disorders  when  applied  to  the 
Surface  of  the  Body  or  used  internally,'  4th  edit.  London,  1805  ;  Tripier 
and  Bouveret's  'La  Fievre  typhoide  traitee  par  les  Bains  froids,'  Paris, 
1886  ;  Fismer, '  Kaltwasserbehandlungbei  der  acuten  Crouposen  Pneumonie,' 
Deutsch.  Arch.  f.  Klin.  Med.  1873  ;  and  the  writer's  '  Text-book  of  General 
Therapeutics,'  London,  1889.  From  the  latter  the  following  account  is 
chiefly  abstracted. 

The  first  person  to  put  the  treatment  of  fevers  by  cold  water  upon  a 
scientific  basis  was  Currie,  the  first  edition  of  whose  work  appeared  in 
1797.  The  great  merit  of  Currie's  work  over  that  of  his  predecessors  is 
that  he  took  the  temperature  of  his  patients.  Giannini  in  1805  gave  an 
account  of  the  employment  of  cold  for  fever.  The  use  of  this  method,  how- 
ever, died  out,  until  it  was  again  brought  under  the  notice  of  the  profes- 
sion by  Brand  in  1861,  and  since  then  many  authors  have  discussed  the 
subject. 

In  considering  the  action  of  a  cold  bath  in  fever  we  have  to  remember 
that  the  thermic  mechanism  of  the  body  consists  of  three  parts  :  (1)  a 
thermogenetio,  by  means  of  which  heat  is  produced  by  changes  going  on 
chiefly  in  the  muscles  which  are  the  main  thermogenetic  organs  of  the 
body  ;  this  function  is  presided  over  by  the  central  nervous  system,  probably 
that  part  of  it  which  is  in  the  neighbourhood  of  the  great  basal  ganglia. 
(2)  A  thermolytic  mechanism  which  presides  over  the  loss  of  heat.  Its 
chief  parts  are  the  cutaneous  vasomotor  system  and  the  sweat-glands.  It  is 
likewise  under  the  control  of  the  central  nervous  system.  Heat  is  lost  from 
the  skin  by  conduction,  radiation,  and  evaporation.  (3)  Lastly,  there  is  a 
thermotaxic  mechanism  whose  function  is  to  maintain  the  balance  between 
the  thermogenetic  and  the  thermolytic.  This  mechanism  must  clearly  be 
nervous.  In  fever  the  production  of  heat  is  enormously  increased.  Those 
pathologists  who  believe  in  the  value  of  antipyretic  methods  of  treatment 
assume  that  the  pyrexia  of  fever  is  harmful,  and  that  by  diminishing  it  we 
benefit  the  patient. 

From  the  above  it  is  seen  that  the  possible  modes  of  action  of  a  cold 
bath  are  very  numerous.  It  is  clear  that  a  cold  bath  must  directly  abstract 
heat.  Maclister  has  shown  that  cold  diminishes  the  thermogenetic  activity 
of  muscle,  and  it  is  almost  certain  that  a  cold  bath  acts  in  this  way,  es- 
pecially if  the  cutaneous  vessels  are  dilated,  as  they  often  are  in  fever,  for 
then  cold  blood  is  quickly  carried  to  the  muscles.  It  is  true  that  when  a 
fever  patient  is  put  into  a  cold  bath  the  rectal  temperature  at  first  rises  a 
little.  This  is  soon  succeeded  by  a  fall,  and  it  may  be  explained  either  by 
the  fact  that  the  water  interferes  with  the  loss  of  heat  by  evaporation  and 
radiation,  or  that  there  is  at  first  a  slight,  temporarily  increased  thermo- 
genesis  which  is  an  abortive  attempt  to  compensate  for  the  direct  abstraction 
of  heat  by  the  cold  water.  After  the  patient  has  been  taken  out  of  the  bath, 
the  temperature  continues  to  fall,  probably  because  for  a  short  time  the 
activity  of  thermogenesis  remains  depressed.  There  are  many  ways  of  em- 
ploying cold  to  reduce  fever.  Simple  sponging  with  cold  water  calls  for  no 
description. 


032  HYGIENE 

The  Cold  Bath. — This  is  undoubtedly  the  most  efficacious.  It  is  best 
apphed  by  means  of  a  long  bath  placed  at  the  end  of  the  bed,  so  that  both 
are  in  the  same  straight  line.  The  patient  with  a  blanket  over  him  is  lifted 
in  a  sheet,  and  by  it  lowered  into  the  water  while  the  blanket  remains  over 
the  top  of  the  bath.  To  lift  him  out,  several  persons  place  their  hands  under 
him  and  the  wet  sheet  is  left  behind ;  he  is  put  back  into  bed  and  a  sheet  or 
simple  blanket  is  thrown  lightly  over  him.  The  temperature  of  the  bath 
should  be  between  58°  and  08°  F.  or  warmer,  if  that  of  the  patient  be  high. 
The  point  of  fever  heat  at  which  he  should  be  bathed  varies  with  the  disease. 
The  inmiersioil  should  last  about  ten  minutes,  for  the  quantity  of  heat  which 
at  the  end  of  this  time  can  be  further  abstracted  is  small,  as  the  rapidity 
with  which  heat  is  given  from  a  hot  body  to  a  cold  one  increases  with  the 
diii'erence  of  temperature  between  the  two.  Hence  short  bathings  frequently 
repeated  are  much  more  potent  than  long  ones.  The  temperature  of  the 
bath  may  be  higher  in  children,  for  they  present  a  much  greater  projjortional 
surface  from  which  to  withdraw  heat.  In  private  practice  there  is  some- 
times much  inconvenience  in  arranging  the  bath.  This  difficulty  may  be 
surmounted  by  raising  the  head  of  the  bedstead  a  few  inches  and  thereby 
makii:ig  an  inclined  plane  of  it.  Under  the  patient  a  large  macintosh  sheet 
is  placed  and  it  is  extended  over  a  bank  of  pillows  on  either  side,  a  gutter  is 
made  in  the  macintosh  at  the  foot  of  the  bed  so  that  cold  water  poured  in 
at  the  head  will  run  out  at  the  foot,  where  it  is  caught  in  some  suitable 
vessel.  The  pillows  at  the  side  may  be  so  high  that  the  patient  lies  in  a 
stream  of  running  water. 

The  Tepid  Bath  gradually  cooled. — This,  first  employed  by  Ziemssen,  is 
applied  thus :  The  patient  is  put  into  a  bath  the  temperature  of  which  is 
from  9°  to  10°  F.  below  that  of  liis  body.  Cold  water  is  then  gradually  poured 
in  till,  after  ten  or  fifteen  minutes,  the  temperature  of  the  bath  has  fallen  to 
about  08°  F.  He  remains  in  from  twenty  to  thirty  minutes,  when  generally 
severe  shivering  or  chattering  of  the  teeth  begins.  He  is  then  quickly  moved 
back  to  a  bed  which  has  been  previously  warmed.  This  method  is  not 
nearly  so  potent  as  the  cold  bath,  and  is  more  difficult  to  carry  out ;  never- 
theless it  has  two  great  advantages — namely,  that  it  is  more  comfortable  to 
the  patient ;  and  that  it  can  be  used  for  cases  in  which,  from  the  condition 
of  the  heart,  there  is  any  likelihood  that  the  shock  of  the  cold  may  be  too 
severe. 

The  Cold  Affusion. — This  is  the  method  Currie  used,  for  he  threw  cold 
sea-water  over  those  whom  he  treated.  The  patient  should  be  placed  in  an 
empty  bath,  and  water  at  about  00°  F.  thrown  over  him  ;  this  is  done  for 
about  five  minutes.  The  cold  affusion  is  now  but  rarely  used,  for  the  reduc- 
tion of  temperature  caused  by  it  is  but  slight,  and  the  shock  is  so  great  as 
to  be  extremely  disagreeable.  It  is  absolutely  forbidden  when  there  is  any 
sign  of  cardiac  mischief.  Possibly  some  of  Currie's  good  results  may  be  set 
down  to  the  fact  that  he  used  salt  water,  which  is  more  stimulating  than 
fresh. 

The  Cold  Pack. — The  naked  patient  is  wrapped  in  a  sheet,  four  folds 
thick,  which  has  been  wrung  out  in  cold  water,  and  is  carefully  placed  between 
the  thighs  and  axillfe.  It  is  often  recommended  that  the  sheet  should  not 
quite  reach  to  the  feet,  because  of  the  difficulty  of  throwing  it  over  them. 
Outside  it  a  blanket  is  thrown.  In  five  or  ten  minutes  the  patient  is  removed 
from  between  the  folds  of  the  sheet  and  a  fresh  one  is  substituted.  This 
is  more  easy  if  there  are  two  beds.  The  process  is  repeated  four  or  eight 
times,  and  even  then  is  not  so  powerful  as  a  cold  bath. 

Ziemssen  and  Immerman  give  the  proportionate  efficacy  of  the  cold  affusion, 


BATHS  G33 

■a  series  of  four  cold  packings,  the  gradually  cooled  bath  and  the  cold  bath, 
at  1  :  2  :  3  :  4.  Cold  baths  administered  to  febrile  patients  in  the  latter  part 
■of  the  evening  and  in  the  night  cause  a  more  durable  and  a  greater  reduc- 
tion of  the  temperature  than  those  given  in  the  daytime,  and  the  reduction 
produced  by  a  nocturnal  cold  bath  is  greater  than  would  be  the  difference 
between  night  and  day  temperatures  in  the  same  case  if  it  had  not  been 
treated  by  a  cold  bath.  This  is  due  no  doubt  in  part  at  least  to  the  fact  that 
at  night  the  temperature  is  naturally  falling,  and  that  it  is  easier  to  reduce  a 
falling  temperature  than  a  rising  one.  We  thus  learn  that  baths  ought 
to  be  continued  through  the  night. 

We  will  now  briefly  consider  some  of  the  diseases  for  which  the  cold 
bath  treatment  has  been  employed. 

Typhoid  Fever. — The  cold  bath  has  been  very  much  used  for  this  disease, 
and  in  many  institutions  it  was  the  routine  practice.  Numerous  statistics 
have  been  published,  and  they  all  show  that  the  mortality  from  typhoid 
fever  since  the  introduction  of  the  cold  bath  is  much  less  than  it  was  before. 
Murchison  calculates  that  the  mortality  of  typhoid  fever  when  treated  on  the 
expectant  plan  is  17*45  per  cent.,  and  Jaccoud  says  it  is  19'28.  Brand  puts 
the  mortahty  after  the  introduction  of  the  cold  bath  treatment  at  6  per  cent. 
If  we  contrast  the  treatment  at  the  same  hospital  before  and  after  the  intro- 
duction of  the  cold  bath  we  find  the  contrast  very  distinct.  Liebermeister's 
statistics  show  that  at  Basle  from  1854  to  1864  mortahty  under  the  expect- 
ant symptomatic  treatment  was  18-1  per  cent.  The  mortality  in  subsequent 
years  among  those  who  were  treated  by  the  cold  bath  was  11*2  per  cent.,  and 
many  other  statistics  might  be  quoted  all  showing  a  great  fall  in  the  death- 
rate.  In  Germany  it  is  usual  to  fix  the  temperature  at  which  a  bath  should 
be  given  at  102°-2  F.  Many  place  it  at  108°  F.  In  order  to  get  the  best 
results  possible  the  case  must  be  consistently  treated  from  the  beginning. 

Fever  patients  come  under  treatment  more  frequently  late  than  early,  yet 
among  twenty  patients  whose  deaths  are  recorded  by  Tripier  and  Bouveret,  in 
seven  the  treatment  had  been  begun  after  the  twentieth  day,  in  ten  between 
the  eighth  and  sixteenth  days,  and  in  three  only  during  the  first  week.  One 
can  never  say  what  course  a  case  of  typhoid  fever  will  take,  and  therefore  it 
is  very  important  to  begin  the  treatment  early,  even  if  the  case  appear  to  be 
mild. 

It  might  be  thought  that  cold  bathing  would  increase  the  frequency  of 
complications,  especially  bronchitis  and  pneumonia ;  but  this  is  not  the  case. 
Hoffmann  and  Liebermeister  estimate  that,  while  the  complications  from 
severe  lung  mischief  anions:  those  treated  on  the  expectant  method  was  20 
per  cent.,  among  those  treated  by  cold  baths  it  is  only  7-7  per  cent. 

Experience  has  shown  that  epistaxis,  pleurisy,  and  albuminuria  are  not 
contraindications  to  the  treatment.  Of  course  perforation  of  the  intestine 
and  peritonitis  are  absolute  contraindications  to  treatment  by  cold  baths,  and 
so  is  intestinal  hemorrhage,  if  it  be  severe,  but  not  if  it  be  mild.  If  the 
patient  suffers  from  severe  heart  disease,  or  if  he  is  very  collapsed  when  first 
seen,  a  cold  bath  should  not  be  given.  Pregnancy,  menstruation,  phthisis, 
bronchitis,  obesity  and  old  age  are  not  in  themselves  contraindications. 

Cold  baths  not  only  reduce  the  temperature ;  they  also  benefit  the  patient 
in  other  ways.  At  first  the  contact  with  the  cold  is  very  disagreeable,  but 
after  a  short  time  he  feels  much  more  comfortable,  the  pulse  and  respirations 
fall  in  frequency,  and  often  delirium  disappears,  and  all  those  symptoms 
which  make  up  the  typhoid  condition  are  ameliorated. 

The  application  of  cold  does  not  shorten  the  fever,  it  only  diminishes  its 
intensity.     Eelapses  are  said  to  be  more  frequent  after  the  administration  of 


634  HYGIENE 

the  cold  bath  than  they  are  if  the  patient  is  treated  without  them,  but  the- 
difiference  is  so  shght  as  to  be  of  no  practical  consequence.  It  is  probable 
that  ultimately  some  of  the  newly  introduced  antipyretic  drugs,  such  as  anti- 
februi,  will,  to  a  large  extent,  replace  the  use  of  the  cold  bath  for  typhoid 
fever. 

Typhus  Fever. — This  was  the  malady  for  which  Currie  principally  used  the 
cold-water  treatment.  Jiirgensen  and  Brand  have  also  used  it  with  good 
results. 

Pneumonia. — Of  late  years  the  treatment  of  pneumonia  by  cold  water, 
externally  applied,  has  come  much  mto  vogue,  especially  in  Germany. 
Liebermeister  states  that  by  it  the  mortality  from  this  disease  in  the  hospital 
at  Basle  has  been  reduced  from  2o-3  to  IG'8  per  cent.  Fismer  contrasts  230 
cases  treated  before  the  introduction  of  the  cold  bath  with  the  same  number 
treated  by  it,  and  finds  the  deaths  to  be  sixty  in  the  first  series,  as  against 
thirty-eight  in  the  second.  He  fixes  the  temperature  at  which  the  bath 
should  be  given  at  102°-2  F.  It  does  not  appear  that  the  disease  is  curtailed 
by  it. 

Bheumatic  Fever.— The  majority  of  cases  of  this  disease  are  so  adequately 
treated  by  compounds  of  salicyhc  acid,  or  by  the  acid  itself,  that  they  da 
not  require  to  be  treated  by  cold  baths  ;  but  the  case  is  different  with  rheu- 
matic hyperpyrexia.  Here  the  temperature  rises  so  rapidly  that  most  ener- 
getic means  must  be  adopted  the  moment  there  are  any  symptoms  of  the 
onset  of  hyperpyrexia  ;  by  this  means  the  most  desperate  cases  can  be  saved. 
The  Clinical  Society  appointed  a  committee  to  investigate  the  subject,  and 
they  reported  that  out  of  the  cases  which  were  not  bathed  only  one,  in  which 
the  maximum  temperature  exceeded  106,  recovered  ;  but  of  the  cases  which 
were  bathed  fifteen,  or  five-eighths  of  the  total  in  which  the  maximum  ex- 
ceeded 106,  recovered.  In  six  out  of  eleven  fatal  cases  which  were  not  bathed^ 
the  maximum  was  under  106  ;  but  in  only  three  out  of  twenty-two  fatal  bathed 
cases  was  it  so  low.  A  perusal  of  the  report  of  the  committee  will  show  that 
energetic  cold  water  bathing  is  most  necessary  in  all  cases  of  rheumatic 
hyperpyrexia. 

Cold-water  bathing  has  been  employed  for  almost  every  disease  accom- 
panied by  a  rise  of  temperature.  Thus  it  has  been  used  for  scarlet  fever, 
small-pox,  measles,  pleurisy,  meningitis,  and  erysipelas. 

Uses  of  Wabm  Baths 

These  are  most  used  for  washing,  and  for  that  purpose  are  far  more  effi- 
cacious than  cold,  because  they  aid  the  removal  of  the  fatty  secretions  of  the 
skin. 

Their  uses  need  not  occupy  us  long,  for  they  have  been  already  indicated  in 
the  account  given  of  the  physiological  action  of  warm  baths.  They  are  used 
for  two  main  purposes,  dilatation  of  the  cutaneous  vessels,  and  the  soothing 
of  pain. 

Dilatation  of  cutaneous  vessels  is  required  whenever  we  wish  to  abstract 
blood  from  internal  parts.  Thus  a  warm  bath  promotes  sleep  if  taken  im- 
mediately before  going  to  bed,  as  it  withdraws  blood  from  the  brain;  but  it  is, 
of  course,  essential  that  the  patient  should  go  to  bed  immediately  after  the 
bath  and  be  thoroughly  wrapped  up  so  that  the  dilatation  may  be  maintained. 
General  weariness  is  relieved  by  a  hot  bath,  because  it  withdraws  blood  from 
internal  organs  and  thus  rests  them.  A  hot  bath  is  a  favourite  remedy  for 
a  cold  and  other  mild  inflammatory  disorders,  for  the  reason  that  the  blood 
is  diverted  from  the  inflamed  part  to  the  skin ;  here,  also,  it  is  important 


BATHS  635 

that  the  patient  should  after  the  bath  at  once  go  to  bed  and  be  wrapped  in 
blankets  to  maintain  the  dilatation.  Warm  baths  are  largely  used  for  the 
diaphoresis  which  occurs  after  them  ;  for  this  reason  they  are  employed  in 
Bright's  disease.  In  this  malady,  as  it  is  very  desirable  to  maintain  the  heat 
for  some  time,  a  hot  pack  or  hot-air  bath  is  often  to  be  preferred  to  a  hot- 
water  bath.  To  maintain  the  diaphoresis  after  any  of  these  the  patient  should 
be  well  wrapped  in  hot  blankets. 

Warm  water  is  largely  used  to  relieve  pain  and  muscular  spasm,  as  we 
see  in  its  application  for  renal,  intestinal,  and  biliary  colic,  and  also  in  the 
fact  that  a  catheter  can  often  be  passed  successfully  in  a  warm  bath,  when 
previously  all  attempts  had  failed.  A  warm  bath  is  a  very  frequent  remedy 
in  infantile  convulsions.  Certain  skin  diseases  in  which  there  is  a  large 
accumulation  of  scales,  such  as  psoriasis,  very  chronic  eczema,  and  exfoliative 
dermatitis  are  improved  by  warm  baths.  For  these  maladies  Hebra  so  ar- 
ranges a  bath  that  a  patient  can  remain  in  it  for  days  at  a  time,  without 
getting  out  to  relieve  either  the  bowels  or  the  bladder.  The  water  is  pleasantly 
warm  and  is  kept  at  a  constant  temperature.  Tepid  baths  allay  irritation, 
and  are,  therefore,  of  use  for  the  itching  of  prurigo,  the  tingling  of  erythema, 
and  the  itching  of  jaundice.  Dujardin-Beaumetz  recommends  them  for  use 
during  the  eruptive  stage  of  small-pox.  For  the  above  purposes  they  are 
generally  employed  at  the  patient's  own  house,  but  there  are  a  large  number 
of  bathing-places  whose  reputation  rests  solely  upon  their  warm  baths.  They 
are  chiefly  used  for  chronic  rheumatoid  arthritis,  and  to  absorb  chronic  in- 
flammatory products.  Leichtenstern  says  :  '  It  is  a  matter  proved  by  multi- 
plied observation  that  the  products  and  residue  of  chronic  inflammation  and 
hyperplexia  of  tissue  can  be  favourably  influenced  by  the  use  of  warm  baths. 
The  old  and  deserved  reputation  of  thermal  springs  in  the  treatment  of  chronic 
rheumatism  of  joints  and  muscles,  of  rheumatic  contraction  and  false  anky- 
losis, of  the  effects  of  past  attacks  of  gout,  can  hold  its  own  even  against  the 
extreme  of  scepticism.  The  methodic  use  of  thermal  waters  often  improves 
and  cures  certain  chronic  skin  affections,  ulcerous  processes  of  the  skin,  badly 
granulating  torpid  wounds,  fistulas  and  caries  of  bone,  cicatrices  distorting 
the  skin,  muscle,  sinew  and  joint  exudations  that  remain  behind  after  luxations, 
fractures,  and  gunshot  wounds,  and  which  often  interfere  so  much  with  the 
function  of  the  parts  affected.  Chronic  exudations  also  after  pleurisy,  pelvic 
peritonitis,  perityphlitis,  peri-  and  parametritis  may  at  times  be  ameliorated 
by  warm  baths.  Undoubtedly  certain  affections  of  the  nervous  system  are 
suitable  for  the  employment  of  thermal  baths,  for  they  are  often  appropri- 
ately employed  in  various  forms  of  old  stationary  cerebral,  spinal,  peripheral 
and  taxic  paralyses  ;  further,  in  various  neuralgias  and  hypersesthesias,  in 
some  forms  of  hysteria,  neurasthenia,  and  hypochondria '  (Leichtenstern ; 
Ziemssen's  'Handbook  of  General  Therapeutics'). 

The  following  is  a  list  of  the  more  important  places  which  are  celebrated 
for  their  warm  springs.  The  figures  indicate  the  temperature  in  degrees 
Fahrenheit : — 

Aix-les-Bains  (90-114) ;  Badenweiler  (79-100) ;  Baden  (114-120) ;  Bath 
(107-117);  Bormio  (95-104);  Brussa  (55-170);  Buxton  (82);  Dax 
(116-140) ;  Gastein  (95-138) ;  Hammam-Mescontin  (115-203)  ;  Hammam- 
E'Hira  (107-110)  ;  Leukerbad  (102-124)  ;  Neris  (118-125)  ;  Pistyau 
(86-104)  ;  Plombieres  (66-158) ;  Pfaffers  (104) ;  Ponte  Seraglio  (100-129)  ; 
Eagatz  (96) ;  Eomerbad  (93-99) ;  Schlangenbad  (80-89) ;  Teplitz  (105-118) ; 
Warmbrunn  (96-107) ;  Wildbad  (93-102). 

The  innumerable  local  uses  for  warmth  hardly  fall  within  the  scope  of  this 
article.     Hot  sitz  baths  have  already  been  mentioned. 


C36  HYGIENE 


USES   OF  BATHS   CONSIDEKED   ACCORDING   TO   THEIR   CONSTITUENTS 

In  this  place  we  will  only  consider  natural  baths,  and  they  are  quickly 
dismissed,  for,  as  has  already  been  pointed  out  (p.  G27),  there  is  no  evidence 
whatever  that  substances  dissolved  in  water  to  such  a  slight  extent  as  they 
are  found  in  natural  waters  have  any  effect  whatever.  All  the  good  that 
patients  profess  to  obtain  from  such  baths  is  to  be  attributed  either  to  the 
temperature  of  the  water  or  to  the  accessories,  such  as  fresh  air  and  good 
diet,  which  are  met  with  at  the  bathing  establishments.  For  example,  in 
olden  days  the  most  marvellous  effects  were  attributed  to  sulphur  baths,  but 
it  is  interesting  to  note  that  at  the  most  celebrated  places  possessing  sulphur 
baths  the  water  was  warm  and  the  diseases  for  which  sulphur  baths  were  re- 
commended were  just  such  as  would  be  benefited  by  warm  baths.  The  con- 
sideration of  the  constituents  of  the  bath  naturally  leads  us  to  sea-bathing. 


Sea  Baths 

The  following  table  will  show  that  these  fall  under  the  heading  of  cold 
baths.     The  mean  summer  temperatures  of  the  sea  are  : — 

Degrees  Falirenheit 

Mediterranean 71"6  to  80'6 

Atlantic  (European) 68      „  73"4 

German  Ocean 60'8  „  64-4 

Baltic  Sea 59      „  62-6 

The  following  table  of  the  composition  of  ocean  water  shows  that  chloride 
of  sodium  is  the  only  important  constituent  : — 

Chloride  of  sodium    .........  25*1 

Chloride  of  i^otassium        ........  '5 

Chloride  of  magnesium 3-5 

Sulphate  of  magnesium '    .         .  5-78 

Sulphate  of  lime -15 

Carbonate  of  magnesium  ........  -IS 

Carbonate  of  lime      .         .         .         .         .         .         .         .         .  '02 

Carbonate  of  potassium      ........  '23 

Iodides  and  bromides          ........  traces 

Organic  matter traces 

Water 964-54 

Total     .  1000-00 

The  composition  of  sea  water  in  various  parts  of  the  world  is  as  follows, 
the  quantity  of  salts  being  expressed  in  parts  by  weight  in  1,000  : — 

Dead  Sea  227-69 

Mediterranean  at  Marseilles 40-7 

South  Atlantic 36-4 

North  Atlantic 35-97 

Pacific 34 

Indian  Ocean 33-86 

English  Channel 32-35 

German  Ocean 29-0 

Black  Sea 15-9 

Baltic 5  to  9 


BATHS  C37 

We  have,  therefore,  to  deal  with  a  cool  bath  consisting  of  a  strong  solution 
of  common  salt.  To  avail  himself  of  the  bath  the  patient  must  live  at  the 
sea- side,  and  it  must  be  taken  in  the  open  air  and  its  water  be  constantly 
moving. 

We  have  already  seen  that  a  cool  bath  is  a  stimulant,  that  it  produces  a 
feeling  of  exhilaration  and  strength,  that  the  faculties  are  quickened,  and  that, 
within  certain  limits,  it  conduces  to  maintaining  a  healthy  condition.  All 
the  virtues  of  an  ordinary  cool  bath  are  intensified  in  a  sea  bath  by  the 
motion  of  the  water,  and  it  is  probable  that  the  salt  itself  has  some  slight 
stimulating  effect ;  but  this  is  but  small  in  comparison  with  the  advantages 
derived  from  the  temperature  of  the  water  and  its  movement.  The  sea  air 
is,  no  doubt,  a  powerful  factor  in  aiding  the  robust  health  often  attained  by 
persons  living  in  towns  when  they  come  to  the  sea-side  for  sea-bathing. 

It  is  difficult  to  name  any  diseases  which  are  specially  benefited  by  sea- 
bathing. It  helps  to  maintain  the  health  of  the  healthy,  and  it  is  particularly 
serviceable  in  restoring  to  health  those  who  are  pale,  anemic,  and  wasted, 
and  those  who  are  convalescent  from  any  serious  disease.  Those  weak,  sickly, 
sallow  creatures  so  often  seen  among  the  poorer  inhabitants  of  towns  are 
usually  regenerated  by  a  course  of  sea-bathing.  They  regain  their  colour, 
they  put  on  flesh,  and  their  strength  is  restored.  These  who  are  usually 
said  to  be  scrofulous  are  much  benefited  by  sea-bathing. 

Weakly  individuals  should  only  take  one  sea-bath  a  day.  It  should 
always  be  before  1  p.m.,  and  is  best  taken  about  two  hours  after  breakfast. 
The  bather  should  not  stay  in  the  water  more  than  five  minutes,  if  he  cannot 
swim,  and  not  more  than  ten  minutes  if  he  can.  He  should  dry  and  dress 
quickly  on  leaving  the  water.  Before  breakfast  is  a  good  time  for  the  healthy 
to  bathe,  and  immediately  after  a  meal  is  a  bad  time  for  anyone  to  take  any 
sort  of  bath.  If  the  bather  is  overheated  from  exertion,  a  sea  bath,  or,  in 
fact,  any  kind  of  bath,  should  be  taken  at  once,  if  it  be  taken  at  all,  before 
the  body  begins  to  cool. 

Turkish  Bath 

There  may  be  found  in  Lane's  '  Modern  Egyptians  '  a  very  good  account 
of  a  Turkish  iDath  as  it  is  used  in  Eastern  countries,  which  shows  that  it  is 
pretty  much  the  same  as  our  Turkish  bath.  Therefore  I  shall  only  mention 
briefly  the  points  in  connection  with  an  ordinary  Turkish  bath. 

The  bather  is,  first  of  all,  required  to  take  off  his  boots,  and  he  is  then 
shown  into  the  first  room,  which  is  a  large  room  with  couches  and  chairs 
placed  all  round  it,  and  usually  with  a  fountain  of  water  in  the  centre.  The 
temperature  of  this  room  is  generally  about  60°  F.,  and  it  is,  in  the  best  baths, 
tastefully  decorated.  Here  the  bather  undresses  and  wraps  a  cloth  round 
his  loins.  He  then  goes  to  the  first  hot  room,  the  temperature  of  which  is 
110-120°  P.,  and  here  he  sits  or  lies  for  some  time.  This  room  is  tiled  or 
made  of  marble,  and,  if  the  bather  lie  down,  he  lies  on  a  marble  couch  with 
a  small  pillow  under  his  head.  He  stays  here  for  about  half  an  hour  whiling 
away  the  time  talking  and  reading,  during  which  some  take  a  glass  of  water 
or  lemonade  to  drink.  After  he  has  been  a  little  while  in  this  room  he 
u.sually  begins  to  sweat  profusely.  The  next  room  to  which  he  goes  is  the 
same  in  structure  as  the  first  hot  room.  Its  temperature  is  higher,  usually 
about  150°  degrees.  Here  the  bather  remains  for  a  shorter  time  than  in  the 
first  hot  room,  and  during  his  stay  he  sweats  still  more.  He  may  proceed 
to  other  hotter  rooms,  the  number  and  temperature  of  which  vary  at  different 
baths.     In  some  there  are  three  more,  the  temperature  of  the  hottest  being 


C38  HYGIENE 

fron:  250°  to  300°  F.  ^Yllcn  the  bather  lias  left  the  hotter  rooms  he  goes 
back  to  the  first  hot  room,  where  he  is  thoroughly  kneaded  and  shampooed 
all  over.  The  shampooer  massages  all  the  muscles  and  rapidly  moves  the 
chief  joints.  The  arms  are  usually  first  done,  then  the  legs,  and  lastly  the 
trunk.  This  being  finished,  the  bather  goes  to  the  washing-room,  where  he 
is  lathered  all  over,  and  the  lather  is  washed  off  with  warm  or  cold  water 
which  is  thrown  over  him.  Some  then  take  a  cold  plunge  bath,  while  others 
prefer  a  cold  douche.  The  next  stage  is  to  return  to  the  dressing-room, 
where  the  body  is  lightly  dried  and  the  bather  sits,  well  wrapped  up  in  a 
large  towel,  for  half  an  hour  or  so,  during  which  time  he  can  smoke  and 
drink  a  cup  of  coffee.  He  then  dresses  and  the  bath  is  over.  This  is  the 
usual  course  of  the  proceeding,  but  there  are  many  variations.  Sometimes 
a  cold  douche  is  taken  immediately  upon  entering  the  first  hot  room,  some- 
times the  hot  rooms  are  taken  in  a  different  order  to  that  mentioned  above, 
the  most  usual  variation  being  that  the  bather  goes  first  into  the  hottest  room 
and  then  gradually  passes  through  the  others. 

The  most  obvious  effect  of  the  hot  air  is  that  it  produces  a  great  increase 
in  the  perspiration,  which  literally  runs  down  the  body.  There  is,  at  the  same 
time,  considerable  hypertpmia  of  the  skin.  The  sweat  evaporates  very  fast  and, 
therefore,  the  temperature  of  the  body  does  not  rise  as  much  as  it  otherwise 
Avould,  and  it  is  also  kept  down  by  the  evaporation  of  the  pulmonary  aqueous 
vapour.  Those  who  drink  plenty  of  water  naturally  sweat  more  than  those 
who  do  not.  Some  before  going  into  the  hot  rooms  contract  the  cutaneous 
vessels  by  throwing  cold  water  over  themselves.  The  respiration  and  pulse 
are  both  quickened  and  there  is  some  loss  of  weight.  Many  persons  complain 
considerably  of  cardiac  palpitation  in  the  hottest  rooms.  The  follomng 
table,  compiled  from  Frey  and  Heiligenthal's  '  Luft-  und  Dampf bader,'  shows 
some  of  the  effects  of  a  Turkish  bath  : — 

Condition  before  the  bath  :  — 

Weight,   66,150  grammes ;   pulse,   72 ;    respiration,   15 ;    axillary   temperature, 
36°-9  C.  ;  rectal  temperature,  37°-7  C. 
In  a  room  at  a  temperature  of  50°  C. 
At  the  end  of  10  minutes  : — 

Pulse,  94  ;  respiration,  17 ;  axillary  temperature,  37°'l  C.  ;  rectal   temperature, 
37°-7  C. 
At  the  end  of  15  minutes  the  sweating  began. 
At  the  end  of  20  minutes  : — 

Pulse,  104 ;  respiration,  18  ;  axillary  temperature,  37°"5  C. ;  rectal  temperature, 
37°-8  C. 
At  the  end  of  30  minutes : — 

Pulse,  104;    respiration,  18;  axillary  temperature,  37°'7  C. ;    rectal  temperature, 
37"-9  C. 
The  patient  then  went  to  a  room  at  65°  C. 
At  the  end  of  5  minutes  :  — 

Pulse,  110;  respiration,  19 ;    axillary  temperature,  38°  C;    rectal  temperature, 
38°  C. 
At  the  end  of  10  minutes  there  was  very  profuse  sweating. 
At  the  end  of  15  minutes : — 

Pulse,  120 ;  respiration,  19 ;  axillary  temperature,  38°-5  C. ;  rectal  temperature, 
38°-3  C. 
At  the  end  of  20  minutes  there  was  considerable  discomfort : — 

Pulse,  125 ;  respiration,  20  ;  axillary  temperature,  38"^-7  C. ;   rectal  temperature, 
38°-4  C. 
The  patient  then  went  to  rest  in  the  cooling-room. 
At  the  end  of  5  minutes  : — 

Pulse,  95 ;  respiration,  15  ;  axillary  temperature,  36°-0  C.  ;   rectal   temperature, 
37°-7  C. 


BATHS  C39 

At  the  end  of  10  minutes  : — 

Pulse,  80  ;   respiration,  15  ;   axillary  temperature,  36°"7  C. ;  rectal   temperature, 
37°-7  C. 
At  the  end  of  20  minutes  : — 

Pulse,  72  ;  respiration,  15 ;  axillary  temperature,  3G'^-8  C. ;  rectal   temperature, 
37°-7  C. 
Weight  of  the  body  after  the  bath,  65,100  grammes. 
Loss  of  weight  in  the  bath,  960  grammes. 

The  urine  for  the  whole  of  three  days  before  the  bath  was  briglit  yellow.  Its  daily 
averages  were  that  1,567  cubic  centimetres  were  passed,  which  gave  25*7  cubic  centimetres 
to  each  kilogramme  of  body-weight.  The  specific  gravity  was  1018-8.  The  urea  was 
45*47  grammes,  which  gave  0"688  to  each  kilogramme  of  body-weight.  The  uric  acid  was 
0-633  gramme,  which  gave  '009  gramme  to  each  kilogramme  of  body- weight. 

The  urine  for  the  whole  day  of  the  bath  was  red,  clear,  without  sediment,  and  strongly 
acid :  950  cubic  centimetres  were  passed,  which  gave  14*5  cubic  centimetres  to  each  kilo- 
gramme of  body-weight.  The  specific  gravity  was  1027.  The  urea  was  39-90  grammes, 
which  gave  -604  to  each  kilogramme  of  body-weight.  The  uric  acid  was  -860  gramme, 
which  gave  -013  to  each  kilogramme  of  the  body-weight. 

The  authors  give  other  experiments,  but  as  the  above  is  a  typical  one 
there  is  no  need  to  refer  to  others.  It  shows  us  very  well  the  rise  in  the 
pulse,  respirations,  and  temperature  in  the  bath,  and  also  that  soon  after  its 
cessation  these  have  returned  to  normal.  There  is  some  difference  of  opinion 
about  the  alteration  in  the  amount  of  urea.  According  to  Bartels  and 
JSFaunyn,  the  excretion  of  it  is  slightly  increased,  but  the  careful  experiments 
•of  Frey  and  Heiligenthal  show  that  this  is  not  so  during  the  bath,  for  it 
decreased  from  45*47  grammes  as  a  daily  average  before  the  bath  to  39*9 
grammes  during  the  day  of  the  bath.  Their  experiments  seem  so  careful 
that  we  may  probably  conclude  that  they  show  the  effect  of  a  Turkish 
bath  is  to  make  the  urine  dark  in  colour,  strongly  acid,  scanty,  of  a  high 
specific  gravity,  with  a  diminution  in  the  quantity  of  urea  and  an  increase  in  the 
quantity  of  uric  acid.  These  experimenters,  however,  go  on  to  say  that  some 
time  after  the  commencement  of  a  series  of  baths,  even  as  late  as  the  second 
day,  there  is  a  slight  increase  in  the  amount  of  urea  passed,  and  more 
uric,  phosphoric,  and  sulphuric  acids  are  excreted  so  long  as  the  baths  con- 
tinue. It  will  be  noticed  how  soon  after  the  bath  the  pulse  respiration  and 
temperature  returned  to  normal,  and  also  that  there  was  a  considerable  loss 
of  body- weight.  Manensein  gives  the  limit  as  from  a  quarter  of  a  pound  to 
two  pounds,  but  the  writer  has  known  a  man  lose  five  pounds  in  a  bath  of 
an  hour  and  a  half's  duration. 

Oertel  has  made  a  series  of  experiments,  with  the  object  of  determining 
the  relative  value  of  the  various  means  we  possess  of  producing  diaphoresis. 
They  are  not  altogether  satisfactory,  for  it  is  a  very  difficult  matter  to  com- 
pare things  so  different  and  to  have  similar  conditions  of  experiment  in  each 
case.  He,  however,  comes  to  the  conclusion  that  mountain  climbing  is  by  far 
the  most  powerful  means  that  we  possess  of  increasing  the  excretion  of  water 
by  the  skin  and  lungs,  and  that  the  next  most  potent,  but  more  uncertain, 
method  is  the  subcutaneous  injection  of  pilocarpine,  then  a  Turkish  bath,  and 
last  of  all  in  its  efficacy  comes  a  vapour  bath. 

Bearing  in  mind  what  we  have  said  about  the  physiological  action  of  the 
hot-air  bath,  it  is  not  difficult  to  see  its  uses.  In  the  first  place,  it  is,  owing 
to  the  rubbing  of  the  skin,  thoroughly  cleansing  ;  any  excess  of  fatty  matter  is 
rubbed  off,  so  that  subsequently  the  bather's  skin  is  in  a  much  more  healthy 
condition  than  it  was  previously.  The  shampooing  and  massage  cause  a 
feeling  of  comfort  and  strength  after  a  bath.  The  alteration  in  the  condition 
of  the  urine,  such  as  the  increase  of  uric  acid,  the  primary  diminution  and 
subsequent  increase  of  urea,  the  loss  of  body-weight,  the  large  amount  of 


CiO  HYGIENE 

perspiration,  all  show  that  Turkish  haths  must  modify  the  metabolism  of  the 
body,  and  must  also  be  powerful  excretory  agents.  These  circumstances 
probably  explain  the  fact  that  they  are  of  great  use  in  aiding  the  absorption 
of  old  inflammatory  products,  such  as  those  due  to  syphilis,  chronic  rheu- 
matism, rheumatic  myalgia,  and  gout.  Massage  alone  is  useful  in  these 
aflec'tions,  but  still  more  is  the  Turkish  bath  valuable,  for  it  combines  mas- 
sage with  other  aids  to  absorption.  For  the  same  reason  those  who  have 
been  chronically  poisoned  by  lead  or  mercury  usually  derive  benefit  from  a 
course  of  Turkish  baths.  Sciatica  and  neuralgia  are  also  among  the  diseases 
for  which  they  are  to  be  advised,  for  all  the  factors  of  a  Turkish  bath  will  aid 
recovery.  The  profuse  diaphoresis  renders  them  valuable  for  those  suffering 
from  the  chronic  urannia  of  chronic  Bright' s  disease,  and  Frey  and  Heilig- 
enthal  do  not  forbid  them  in  these  cases,  even  if  the  heart  is  hypertro- 
phied,  provided  that  there  are  no  other  contraindications.  The  fact  that 
they  cause  a  loss  of  weight  has  led  to  their  being  largely  used  by  the  cor- 
pulent. No  doubt  they  are  of  use  to  those  who  have  not  sufficient  strength 
of  mind  to  diet  themselves,  but  dietetic  treatment  for  obesity  is  much  more 
valuable  than  a  course  of  Turkish  baths.  If  care  be  taken  not  to  get  a  chill 
on  leaving  the  bath,  a  Turkish  bath  will  often  cure  a  cold  in  the  head,  and 
patients  sufi'ering  from  slight  bronchitis  with  abundant  expectoration  find 
themselves  alleviated  by  one. 

They  should  be  absolutely  forbidden  to  those  who  have  valvular  disease 
of  the  heart  or  aneurysm,  and  must  be  taken  with  great  care  by  the  very 
old  and  by  those  in  whom  there  is  any  reason  to  suspect  a  fatty  heart. 

Local  hot-air  baths  are  chiefly  used  as  a  means  of  producing  diaphoresis 
in  Bright's  disease.  A  cradle-  is  put  over  the  patient  while  he  is  in  bed, 
over  this  the  bed  clothes  are  throA^-n,  and  under  the  cradle  a  lamp  is 
placed.  The  clothes  are  so  arranged  as  to  prevent  the  exit  of  the  hot  air, 
and  such  parts  of  the  patient  as  are  under  the  cradle  are  soon  heated  to  such 
a  heat  that  profuse  perspiration  results.  This  method  is  very  efficacious  and 
is  commonly  used.  It  is  not,  however,  quite  so  much  in  vogue  since  the 
introduction  of  pilocarpine. 

A  form  of  Turkish  bath  which  the  patient  can  use  in  his  own  house  is 
sold.  It  consists  of  an  apparatus  so  arranged  that  when  he  is  sitting  on  a 
chair  a  large  cloth,  which  is  fastened  tightly  round  the  neck,  falls  down 
over  the  chair  to  the  ground,  so  that  the  whole  of  the  patient  except  the 
head  is  contained  in  it.  A  lamp  is  placed  under  the  chair  and  the  cloth 
is  securely  fastened,  so  that  no  air  has  access  from  the  outside.  The  air 
inside  becomes  very  hot  and  profuse  diaphoresis  takes  place.  This  form  of 
bath  is  not  nearly  so  comfortable  as  an  ordinary  Turkish  bath,  and  has  the 
great  disadvantage  that  it  is  not  possible  to  easily  regulate  the  temperature 
in  it. 

Hot  Vapour  or  Eussian  Bath 

This  form  of  bath  is  rarely  used  by  the  English,  but  it  is  met  with  in 
many  foreign  cities  and  bathing  establishments.  As  probably  many  of  my 
readers  are  unacquainted  with  it,  I  quote  the  following  description  of  a  Eussian 
bath  from  Kohl's  '  Eussia  : ' — The  passage  from  the  door  is  divided  into  two 
behind  the  checktaker's  post,  one  for  the  male,  one  for  the  female  guests. 
"We  first  enter  an  open  space,  in  which  a  set  of  men  are  sitting  in  a  state  of 
nudity  on  benches,  those  who  have  already  bathed  dressing,  while  those  whO' 
are  waiting  to  undergo  the  process  take  off  their  clothes.  Eound  this  space 
or  apartment  are  the  doors  leading  to  the  vapour  rooms.  The  bather  is 
ushered  into  them  and  finds  himself  in  a  room  full  of  vapour,  which  is  sur- 


BATHS  641 

rounded  by  a  wooden  platform  rising  in  steps  to  near  the  roof  of  the  room. 
The  bather  is  made  to  he  down  on  one  of  the  lower  benches  and  gradually 
to  ascend  to  the  higher  and  hotter  ones.  The  first  sensation  on  entering 
the  room  amounts  almost  to  a  feeling  of  suffocation.  After  you  have  been 
subjected  for  some  time  to  a  temperature  which  may  rise  to  145°  F.  the 
perspiration  reaches  its  full  activity  and  the  sensation  is  very  pleasant. 
The  bath  attendants  come  and  flog  you  with  birchen  twigs,  cover  you  with 
a  lather  of  soap,  afterwards  rub  it  off,  and  then  hold  over  you  a  jet  of  ice- 
cold  water.  The  shock  is  great,  but  is  followed  by  a  pleasant  feeling  of  great 
comfort  and  of  alleviation  of  any  rheumatic  pains  you  may  have  had.  In 
regular  establishments  you  go  after  this  and  lie  down  on  a  bed  for  a  time 
before  issuing  forth.  But  the  Russians  often  dress  in  the  open  air,  and 
instead  of  using  a  jet  of  ice-cold  water  go  and  roll  themselves  in  the  snow. 

The  physiological  effects  of  such  a  bath  are  much  the  same  as  those  of 
Turkish  baths,  and  the  differences  will  easily  be  gathered  when  we  remember 
that,  owing  to  the  saturation  of  the  air  of  the  chamber  with  moisture,  the 
sweat  cannot  evaporate.  Thus  high  temperatures  that  are  comfortably 
endured  in  a  Turkish  bath  cannot  be  borne  in  a  Russian  bath.  The  tem- 
perature of  the  bather,  however,  tends  to  rise  much  more  rapidly  in  the 
vapour  bath  than  in  the  dry-air  bath.  To  give  an  instance,  Bartels  has  seen 
the  temperature  of  the  rectum  of  a  man  of  51  kilogrammes  in  a  vapour  bath 
of  127°-4  F.  rise  in  ten  minutes  from  100°-4  to  104°-5  F.  In  a  vapour  bath 
of  12B°*8  F.  the  temperature  of  the  same  individual  rose  from  100°'4  in  eight 
minutes  to  103°,  and  in  thirty  minutes  to  107°.  The  pulse  and  respiration  are 
increased  in  frequency,  as  indeed  they  always  are  by  any  form  of  hot  bath. 

Frey  and  Heiligenthal  have  carried  out  a  series  of  experiments  with  the 
hot-vapour  bath,  and  as  an  example  we  will  quote  those  performed  upon  the 
same  patient  as  were  those  quoted  in  the  description  of  the  Turkish  bath. 
After  three  days  of  the  daily  administration  of  a  Turkish  bath,  there  were 
three  days  during  which  no  bath  was  taken,  then  there  were  three  days 
during  which  a  Russian  bath  was  taken  daily.  The  air  was  saturated  with 
vapour  and  the  temperature  of  the  bath  was  113°  F.  The  averages  of  the 
urine  for  the  three  days  preceding  the  bath  were  1,683  c.c,  or  25*5  c.c. 
to  each  kilogramme  of  body-weight.  The  specific  gravity  was  1,021.  The 
urea  was  52-68  grammes,  or  "783  gramme  per  kilogramme  of  the  body- 
weight.  The  uric  acid  was  '858  gramme,  or  -013  gramme  to  each  kilo- 
gramme of  body-weight. 

Before  the  bath  : — 

Weight  of  body,  65,800  grammes  ;  pulse,  72. 

Eespiration,  17  ;  axillary  temperature,  36°-9  C. ;  rectal  temperature,  37°-7  C. 
After  five  minutes  in  the  vapour  room  :— 

Pulse,  94 ;   respiration,  19  ;  axillary  temperature,  37°-l  C. ;  rectal  temperature,^ 
37°-7  C. 
After  10  minutes  in  the  vapour  room : — 

Pulse,  110;  respiration,  20;   axillary  temperature,  38°  C;   rectal  temperature, 
37°-8C. 
After  20  minutes  in  the  vapour  room : — 

Pulse,  128 ;  respiration,  22 ;  axillary  temperature,  39°-2  C. ;  rectal  temperature, 
38°-0  C. 
After  25  minutes  in  the  vapour  room : — 

Pulse,  136 ;  respiration,  23 ;  axillary  temperature,  39-6°  C. ;  rectal  temperature, 
38°-8  C. 
The  patient  then  left  the  bath  and  went  into  the  cooling  room. 
After  five  minutes  in  the  cooling  room  : — 

Pulse,  74 ;   respiration,  17  ;    axillary  temperature,   36°  C. ;    rectal   temperature, 
37°-9  C. 
VOL.   I.  T  T 


£42  HYGIENE 

After  15  minutes  in  the  cooling  room  : — 

Pulse,  70 ;  respiration,   17  ;  axillary  temperature,  3G°-7  C. ;   rectal  temperature, 
37°-7  C. 
After  30  minutes  in  the  cooling  room  : — 

Pulse,  70 ;   respiration,  17  ;  axillary  temperature,  3C°-8  C. ;  rectal  temperature, 
37°-6  C. 
Weight  of  body  after  the  bath,  65,000  grammes. 
Loss  of  weight  in  the  bath,  800  grammes. 

Urine  for  the  whole  day  red,  clear,  and  very  acid,  900  cubic  centimetres,  or  13'8  cubic 
•centimetres  to  each  kilogramme  of  body-weight.  Specific  gravity,  1027.  Urea,  38*7 
grammes,  or  '586  gramme  per  kilogramme  of  body-weight.  Uric  acid,  '980  gramme,  or 
•015  gramme  per  kilogramme  of  body-weight. 

This  experiment  shows  us  the  rise  of  pulse,  respiration,  and  temperature, 
the  diminution  in  the  quantity  of  the  urine,  its  higher  specific  gravity,  the 
diminution  of  the  urea  and  the  increase  of  the  uric  acid,  and  the  loss 
•of  hody-weight.  The  pulse  and  temperature  soon  sank  to  a  little  below 
what  they  were  before  the  bath,  and  the  respiration  to  exactly  the  same 
as  it  was  before  the  bath.  During  the  two  days  immediately  after  the 
bath  the  urine  regained  the  condition  it  had  before  the  bath,  except  that 
the  excretion  of  urea  was  decidedly  greater  than  it  was  before  the  bath. 

The  Eussian  bath  is  not  so  valuable  in  the  treatment  of  disease  as  the 
Turkish.  The  warmth,  the  stimulus  of  the  shock  of  the  cold  water  or  snow, 
and  the  stimulus  of  heating  the  body  renders  it  useful  for  chronic  rheumatism 
and  for  the  pain  of  neuralgia  or  sciatica.  Also  the  warm  moist  air  renders 
it  serviceable  for  such  forms  of  dry  bronchitis  as  require  a  moist  exhalation. 
As  the  sweating  is  not  so  abundant  as  in  a  hot-air  bath,  vapour  baths  will 
not  be  so  valuable  to  eliminate  poisons  from  the  system,  nor  so  useful  for 
the  chronic  uremia  of  chronic  Bright's  disease. 

Local  hot- vapour  baths,  rigged  up  like  a  local  hot-air  bath,  are  some- 
times used.  A  cradle  is  put  over  the  patient  and  clothes  over  it.  A  steam 
kettle  is  placed  at  the  end  of  the  bed  and  vapour  is  driven  into  the  space 
under  the  cradle. 

Frey  and  Heiligenthal  thus  contrast  the  hot-air  and  the  vapour  bath. 
In  both  the  common  sensibiHty  of  the  skin  and  the  sense  of  appreciating 
between  hot  and  cold  objects  are  raised.  In  the  Eussian  bath  the  capa- 
bility of  the  muscles  to  respond  to  faradic  stimuli  is  increased,  but  their 
strength  as  measured  with  the  dynamometer  is  diminished.  In  the  Turkish 
bath  there  are  no  alterations  in  these  respects,  but  with  both  forms  of  bath 
there  is  after  them  a  general  feeling  of  well-being  and  strength.  Moment- 
arily on  entering  each  there  is  a  contraction  of  the  cutaneous  capillaries  with 
a  consequent  hard  pulse  and  rise  of  blood  pressure ;  but  immediately  after- 
wards, owing  to  the  dilatation  of  the  cutaneous  capillaries,  the  blood  pressure 
sinks,  the  pulse  rises,  and  the  force  of  the  cardiac  contractions  decreases. 
During  the  stay  in  the  hot  room  there  is  anaemia  of  the  mternal  organs,  but 
h}^erasmia  of  them  after  the  cold  douche.  The  respirations  are  increased 
in  fi'equency  and  the  temperature  rises.  There  is  much  sweating  in  the 
Turkish  and  less  in  the  Eussian  bath.  In  both  the  urine  is  decreased,  and  of 
high  specific  gravity.  At  first  the  excretion  of  urea  is  decreased,  afterwards 
it  is  increased.     The  uric  acid  is  increased. 

Othee  Fobms  of  Artificial  Baths 

There  is  hardly  any  limit  to  the  many  varieties  of  artificial  baths.  The 
following  have  at  various  times  been  used  :  Moor,  peat,  mud,  and  slime  baths, 
pine-leaf  and  various  aromatic  herb  baths,  such  as  hay,  gentian,  camomile. 


BATHS  G43 

juniper,  and  marjoram  baths.  Brine  baths  and  sand  baths  have  been  used,  and 
the  latter  are  now  very  popular.  Among  the  follies  of  medicine  are  tan,  bran, 
malt,  glue,  soup,  milk,  whey,  flesh  extract,  blood,  fermented  wine,  horse  dung, 
guano,  oak  bark,  starch,  soap,  corrosive  sublimate,  mineral  acid,  chloride  of 
calcium,  iron,  and  sulphur  baths.  At  some  bathing  estabhshments  carbonic 
acid  gas  baths  are  to  be  found,  and  at  the  present  time  much  attention  is 
paid  to  baths  of  compressed  and  rarefied  air.  It  is  obviously  unnecessary 
to  describe  all  these,  but  a  short  description  will  be  given  of  the  more  popular. 

Sand  Baths. — The  sand  is  dry  and  is  evenly  heated  throughout  to 
between  116°  and  125°  F.  The  lower  extremities  are  covered  in  it  for  a 
depth  of  five  or  six  inches,  the  abdomen  and  thorax  for  half  an  inch.  The 
cutaneous  capillaries  dilate,  and  a  profuse  perspiration  breaks  out.  The 
sweat  cannot  evaporate  easily  because  of  the  sand,  consequently  the  bodily 
temperature  soon  rises  considerably.  The  sand  and  sweat  form  a  coating 
to  the  body  which  has  after  the  bath  to  be  washed  off.  These  baths  are 
useful  whenever  warmth  and  heat  are  required,  and  therefore  they  are  used 
for  chronic  rheumatism,  chronic  gout,  and  chronic  Bright's  disease. 

Moor,  Peat,  Mud,  and  SlimeBaths. — Some  years  ago  these  were  extremely 
fashionable.  They  are  made  by  mixing  moor  earth,  peat,  mud,  or  slime  with 
water  till  the  specific  gravity  of  the  mixture  is  about  1*2  or  1-3.  The  slime 
used  is  the  deposit  of  organic  matter  found  in  rivers.  They  are  always 
used  warm,  and  any  value  that  they  may  have  depends  not  upon  their  con- 
stituents but  upon  their  temperature.  Plain  warm  water  would  do  equally 
well.  As  an  instance  of  the  effect  of  a  mud  bath  we  may  quote  one  of 
Kisch's  experiments  in  which  he  found  that  a  mud  bath,  the  temperature  of 
which  varied  between  100°  and  104°  F.,  quickened  the  pulse  eight  or  ten 
beats,  but  in  the  course  of  two  hours  it  became  normal.  The  respirations 
were  quickened  and  the  axillary  temperature  was  raised  about  3°  F.  These 
baths  are  chiefly  used  for  chronic  rheumatism. 

Pine  Leaf  Baths. — To  make  these,  a  distillate  and  decoction  made  from 
the  leaves  of  pine  trees  is  added  to  water,  but  there  is  no  evidence  that  it  is 
of  any  value.  Probably  the  efficacy  of  these  baths  depends  entirely  upon 
the  temperature  at  which  they  are  taken. 

Brine  Baths. — A  brine  bath  should  contain  2  to  3  per  cent,  of  common 
salt,  that  is,  about  18  to  27  lb.  to  every  hundred  gallons  of  water.  These 
baths  act  in  the  same  way  as  ordinary  salt  water. 

Mustard  Baths  are  prepared  by  adding  ^  to  1^  lb.  of  mustard  to  every 
100  gallons  of  hot  water.  It  is  usually  added  to  a  local  bath  used  to  the  feet 
for  the  cure  of  a  cold  in  the  head. 

Compressed-Air  Bath 

This  consists  of  a  strong  metal  chamber  circular  in  shape  and  quite  air- 
tight. It  is  generally  comfortably  furnished  with  chairs  and  a  table.  When 
the  patient  is  in  it,  air  can  be  pumped  in  till  the  pressure  is  raised  to  the 
desired  point.  A  full  description  of  such  a  bath  will  be  found  in  the  '  British 
Medical  Journal '  for  April  18,  1885,  by  Dr.  C.  T.  Williams.  There  is  one 
at  the  Brompton  Hospital  in  London,  one  at  Ilkley,  one  at  Ben  Ehydding, 
and  there  are  several  on  the  Continent. 

An  increase  of  pressure  of  f  to  f  of  an  atmosphere  is  usually  employed. 
Anything  beyond  this  is  unnecessary,  and  is  liable  to  produce  disagreeable 
symptoms.  The  patient  at  first  experiences  noises  in  the  ears  and  a  sense  of 
obstruction  and  pain  in  the  tympanic  cavity.  These  symptoms  are  due  to 
the  fact  that  the  air  can  pass  much  more  easily  along  the  external  auditory 

T  I  2 


GU  HYGIENE 

meatus  than  up  the  Eustacliian  tuhe,  and  consequently  the  membrana  tympanf 
is  bulged  mwards.  If  the  patient  swallow  frequently  they  soon  pass  off,  but 
only  to  return  again  when  he  comes  out  of  the  pneumatic  chamber.  General 
sensibility  and  the  senses  of  smell,  taste,  and  touch  are  impaired.  Some  persons 
feel  sleepy.  All  observers  are  agreed  that  the  compressed-air  chamber  in- 
creases the  amplitude  of  the  respirations  and  also  the  pulmonary  capacity. 
According  to  Von  Vivenot,  it  is  about  3  per  cent.,  but  Paul  15crt  puts  the 
figure  as  high  as  7  per  cent.  The  upper  limit  of  the  hepatic  dulness  neces- 
sarily descends,  the  cardiac  area  of  dulness  is  decreased,  and  the  heart  sounds 
become  muflied;  The  frequency  of  the  respirations  is  much  diminished  ;  they 
often  fall  to  twelve  or  thirteen  per  minute.  Should  the  patient  be  suffering 
from  any  pulmonary  disease  which  renders  the  breathing  difficult  it  often  be- 
comes easy,  and  the  extremely  rapid  respirations  of  emphysema  may  fall  to 
normal.  The  amount  of  urea  is  increased,  more  oxygen  is  taken  in,  and  more 
carbon  dioxide  is  given  off.  The  pulse  is  small  and  slightly  less  rapid  than 
before  the  bath.  The  other  changes  are  not  of  sufficient  importance  to  be 
mentioned  here. 

It  is  well  known  that  bridge  builders,  divers,  &c.,  who  are  in  their  occu- 
pation subjected  to  great  increases  of  atmospheric  pressure,  frequently  suffer 
from  bleeding  at  the  nose  and  lungs,  and  paralysis  of  the  lower  extremities 
and  bladder.  These  symptoms,  however,  are  not  due  to  the  compressed  air, 
but  to  the  suddenness  with  which  the  workmen  come  out  of  it  into  the  ordi- 
nary atmosphere.  Therefore,  it  behoves  us  to  increase  and  decrease  the  pres- 
sure in  a  compressed-air  bath  gradually.  The  usual  duration  of  the  stay  in 
the  bath  is  two  hours  :  of  this  time  the  first  half- hour  should  be  occupied  by 
gradually  raising  the  pressure  to  the  desired  point,  then  it  should  remain  at 
that  point  for  an  hour,  and  the  last  half-hour  should  be  occupied  by  the  de- 
crease of  the  pressure.  Many  diseases  have  been  treated  by  it,  but  only  the 
more  important  need  be  mentioned  here. 

Puhnonary  Emphysema. — It  is  for  this  condition  that  the  compressed-air 
bath  has  given  the  most  satisfactory  results.  After  several  baths,  one  taken 
each  day  for  several  days,  the  breathing  becomes  easy,  the  dyspnoea  diminishes, 
the  cough  and  expectoration  are  decreased,  the  respirations  become  slower 
and  deeper,  the  cardiac  and  hepatic  dulness  reappears,  and  the  breath  sounds 
over  the  emphysematous  lung  become  more  audible,  the  vital  capacity  in- 
creases, and  the  girth  of  the  chest  is  lessened.  The  exact  cause  of  the  benefit 
is  not  known.  The  usual  course  is  to  take  a  bath  lasting  two  hours  once  a 
day  for  thirty  consecutive  days. 

Bronchitis.' — This  disease  is  often  benefited  by  a  course  of  compressed-air 
baths,  but  it  is  so  difficult  to  separate  bronchitis  from  its  accompanying 
emphysema  that  it  is  impossible  to  say  how  much  of  the  benefit  is  due  to 
the  treatment  of  the  latter  condition. 

Phthisis. — The  reason  why  compressed  air  is  used  in  this  disease  is  that 
it  is  supposed  to  open  out  every  healthy  portion  of  the  lung  and  to  increase 
the  general  nutrition.  It  is  therefore  chiefly  indicated  in  those  sickly  pale 
subjects  afflicted  with  phthisis  and  who  have  ill-formed  chests.  It  is  said  to 
prevent  the  development  of  phthisis  in  those  who  present  the  above  symp- 
toms without  having  any  actual  signs  in  the  lungs.  The  contraindications 
to  its  use  are  high  fever,  great  weakness,  severe  pulmonary  haemorrhage,  and 
decomposing  processes  going  on  in  the  lungs. 

Asthma.— li  is  stated  that  this  malady  is  much  improved  by  compressed- 
air  baths.  Undoubtedly  if  the  asthma  consists  only  of  those  asthmatical  at- 
tacks which  are  so  commonly  met  with  in  the  subjects  of  emphysema,  the 
treatment  will  as  it  relieves  the  emphysema  diminish  the  frequency  of  the 


BATHS  G45 

■asthma-like  attacks.     It  is,  however,  doubtful  whether  it  has  any  effect  on 
genuine  neurotic  asthma. 

The  other  diseases  which  may  be  treated  by  compressed  air  may  be  found 
•described  in  the  author's  '  Text-book  of  General  Therapeutics.' 

Electric  Baths 

All  that  is  necessary  for  an  electrical  bath  is  some  arrangement  for  send- 
ing the  current,  either  faradic  or  galvanic,  through  the  water  of  the  bath. 
A  form  used  by  Dr.  Eussell  and  described  by  Beard  and  Eockwell  in  their 
■*  Medical  and  Surgical  Electricity  '  is  thus  arranged.  A  long  bath  of  ordi- 
nary shape  is  taken.  A  broad  copper  plate  as  long  as  the  water  is  deep  is 
.attached  to  the  bath  at  either  end  of  it.  These  plates  are  the  poles  of  the 
battery.  At  the  head  of  the  bath  a  board  is  placed  a  little  distance  from 
the  end ;  it  is  sloped  conveniently  and  has  a  slit  in  it,  the  shape  of  the 
patient's  back,  so  that  he  can  lie  against  it  comfortably.  When  now  the  cur- 
rent passes  some  of  it  must  pass  through  the  body.  Some  electric  baths  are 
so  arranged  as  to  allow  the  current  to  pass  through  a  part  only  of  the  body. 

It  has  not  yet  been  proved  that  electrical  baths  are  superior  to  the  more 
easily  applicable  methods  of  using  electricity,  but  it  is  claimed  that  they  are 
particularly  serviceable  for  rheumatoid  arthritis  and  general  exhaustion. 


BATH  AND  BATHEOOM 

All  the  houses  built  nowadays  for  the  accommodation  of  the  middle  and 
upper  classes  are  provided  with  bathrooms.  If  the  house  is  small  one  bath- 
room is  sufficient,  but  if  it  is  large  there  should  be  one  on  every  floor. 

The  bathroom  should  not  open  out  of  a  bedroom  unless  it  is  to  be  used 
solely  by  the  occupants  of  that  bedroom,  for  the  noise  of  the  inflow  of  water 
is  very  disturbing  to  those  who  are  asleep,  and  of  course  it  is  an  extremely 
bad  plan  for  the  only  means  of  access  to  the  bathroom  to  be  through  another 
room.  The  writer  remembers  to  have  seen  a  bathroom  in  the  country  which 
could  only  be  reached  by  going  through  the  drawing-rooms.  It  is  preferable 
to  have  the  bathroom  at  the  side  of  the  house,  not  in  the  centre,  so  that 
the  waste  water  can  be  easily  conveyed  away  to  the  outside.  In  small 
houses  the  water-closet  is  often  placed  in  the  bathroom :  this  is  not  to  be 
commended,  for  the  water-closet  is  useless  to  the  rest  of  the  household  when 
the  bathroom  is  occupied,  and  further,  if  owing  to  imperfections  in  the  water- 
closet  any  foul  air  proceeds  from  it  the  bather  will  inhale  this  air  during  the 
whole  of  the  time  he  is  in  the  bathroom.  Nevertheless  it  is  often  con- 
venient to  have  a  water-closet  close  to  the  bathroom.  The  walls  of  the 
TDathroom  that  are  next  to  the  bath  should  either  be  tiled,  painted,  or  papered 
-with  glazed  paper,  so  that  it  will  not  hurt  them  to  be  splashed.  Frequently 
the  ceiling  and  wall  near  to  the  hot-water  pipes  is  blackened  by  the  current 
of  hot  air  coming  from  the  neighbourhood  of  the  warm  pipes  and  depositing 
dirt  in  their  course.  The  best  way  to  get  over  the  difficulty  is  to  paint  the 
ceiling  instead  of  whitewashing  it,  for  then  it  can  be  frequently  washed. 
What  is  sold  as  cork  carpet  forms  a  good  covering  for  the  floor,  for  it  is 
warm,  smooth,  and  easily  washed ;  the  only  objection  to  it  is  that  when 
washed  it  takes  some  hours  to  dry,  as  the  cork  soaks  up  the  water.  Another 
good  plan  is  to  cover  the  floor  with  linoleum  and  to  have  a  square  of  cork 
on  which  to  step  on  leaving  the  bath.  It  is  very  important  that  a  bathroom 
should  be  well  ventilated,  for  when  a  hot  bath  is  being  taken  the  air  becomes 


GiQ  HYGIENE 

disagreeably  warm  and  moist.  It  is  unnecessary  here  to  indicate  the  various- 
means  used  for  ventilating  a  room  ;  they  are  fully  described  in  another  article. 
A  tireplace  in  a  bathroom  is  a  desirable  luxury,  for  a  fire  by  which  to  dry 
one's  self  is  often  desu-able  for  an  invalid. 

The  materials  commonly  used  for  making  a  bath  are  iron,  zinc,  copper,, 
porcelain,  slate,  and  concrete.  Iron,  zinc,  and  copper  are  always  enamelled 
on  the  interior.  Iron  and  zinc  are  the  cheapest  at  first,  but  they  require 
very  frequently  to  be  re-enamelled  at  least  every  three  or  four  years  if  the 
bath  is  in  constant  use.  This  is  expensive,  and  to  do  it  the  bath  has  to  be 
taken  away  for  a  few  days.  With  an  iron  bath  the  enamel  is  particularly 
liable  to  flake,  because  the  metal  is  very  inelastic,  and  is  easily  oxidised  by 
moisture.  Zinc  baths,  in  addition  to  the  disadvantage  of  flaking,  soon 
change  their  shape,  so  that  the  bottom  does  not  remain  level,  and  con- 
sequently all  the  water  will  not  run  out.  Copper  baths  are  very  durable,  do 
not  alter  their  shape,  nor  are  they  easily  oxidised  ;  but  they  are  expensive, . 
and  the  enamel  comes  off  as  with  any  other  metal  bath. 

Slate  baths  have  the  objections  that  as  they  are  put  together  in  slabs 
they  are  liable  to  leak  at  the  joints,  and  dirt  collects  in  the  corners.  If  they 
are  not  enamelled  it  is  difficult  to  see  when  they  are  clean,  and  if  they  are 
enamelled  the  enamel  soon  flakes  off". 

Concrete  baths  have  only  recently  come  into  use,  so  that  at  present  we 
cannot  say  whether  they  wear  well.     They  are  hea^-y  and  cumbersome. 

Glazed  fire-clay  baths,  or,  as  they  are  commonly  called,  porcelain  baths, 
are  undoubtedly  the  best,  for  they  have  in  the  interior  a  smooth  surface  with 
rounded  corners,  so  that  they  are  very  easy  to  keep  clean  ;  the  glaze  keeps  on 
an  indefinite  time,  so  that  they  always  look  nice,  and  they  are  extremely 
durable.  The  chief  objection  to  them  is  the  primary  cost,  for  they  are 
rather  more  than  twice  the  price  of  an  enamelled  iron  bath,  but  they  are 
cheaper  in  the  long  run,  for  owmg  to  the  frequent  enamellmg  in  a  few  years 
the  total  cost  of  the  iron  bath  exceeds  that  of  the  porcelain.  The  porcelain 
baths,  owing  to  their  great  weight,  are  difficult  to  fix  in  position,  but 
fixed  no  removal  is  ever  necessary.  A  porcelain  bath  abstracts  heat  from 
the  water  rather  more  rapidly  than  a  metal  one  does,  but  the  difference  in 
this  respect  is  not  sufficient  to  be  of  any  practical  importance.  One  of  the 
chief  reasons  why  porcelain  baths  are  dear  is  that  several  are  spoiled  before 
one  perfect  one  is  made  ;  the  result  is  that  they  can  often  be  obtained  at  a 
lower  cost  if  one  be  bought  with  a  slight  blemish  at  the  top,  where  it  does 
not  really  matter.  When  once  they  are  fixed  they  are  not  particularly  liable 
to  get  broken.  Owing  to  their  durability  they  are  very  suitable  for  public 
institutions. 

Both  hot  and  cold  water  should  be  supplied  to  the  bath,  and  the  supply 
pipes  should  be  sufficiently  large  to  allow  the  bath  to  fill  rapidly.  They 
should  not  run  mider  the  bath,  as  then  if  they  get  out  of  order  they  are 
difficult  of  access.  In  some  baths  the  water,  either  hot  or  cold,  or  both, 
flows  in  through  the  same  pipe  as  that  by  which  it  leaves  the  bath :  this 
is  a  particularly  objectionable  arrangement,  for  the  inflowing  water  washes 
back  into  the  bath  all  the  dirty  soap-suds  that  are  lying  in  the  waste-pipe. 
A  very  common  arrangement  is  for  the  hot  and  cold  water  to  come  into  the 
bath  at  the  bottom  by  separate  apertures,  and  for  the  taps  which  are  just 
outside  the  bottom  of  the  bath  to  be  worked  by  handles  at  the  level  of  the  top 
of  the  bath  ;  the  handles  are  connected  to  the  taps  by  long  vertical  iron  rods. 
These  taps  are  very  liable  to  leak  and  to  work  badly,  for  the  iron  rod  is 
almost  certain  in  time  to  bend  a  little  one  way  or  the  other.  The  best 
manner  of  introducing  the  hot  and  cold  water  is  for  the  supply  pipes  to 


BATHS  G47 

come  vertically  up  the  outside  of  the  end  of  the  bath,  for  there  to  be  screw- 
down  taps  at  the  level  of  the  top  of  the  bath,  and  for  the  water  to  come  in  at 
the  top  and  fall  down  into  the  bath  at  the  end.  Most  baths  are  slanting  at 
one  end  and  vertical  at  the  other  ;  the  taps  are  best  placed  at  the  vertical  end. 
The  hot  water  is  usually  supplied  from  a  high-pressure  kitchen  boiler.  All 
apparatus  by  which  the  water  is  heated  in  the  bathroom  itself  by  gas  should 
be  avoided,  as  the  fumes  of  the  gas  are  very  objectionable  and  even  dangerous. 
The  diameter  of  the  outlet  pipe  for  the  waste  water  is  usually  too  small. 
It  should  be  two  inches  for  the  bath  to  empty  with  proper  rapidity.  It  is  of 
course  no  use  to  have  an  ample  waste-pipe  if  the  perforated  holes  through 
which  the  water  flows  out  or  the  water-way  of  the  outlet  tap  are  too  small. 
The  outlet  pipe  should  always  open  directly  into  the  open  air,  and  the  water 
should  fall  some  distance  before  entering  the  pipe  which  is  going  to  convey 
it  directly  to  the  drain.  This  is  most  important  in  order  to  prevent  the 
back  flow  of  sewer  gas  into  the  bathroom.  It  is  not  a  bad  plan  to  conduct 
the  bath  water  into  the  gutter  of  some  adjoining  roof. 

There  should  always  be  under  the  bath  a  leaden  tray  about  two  inches 
deep  with  a  pipe  from  it  into  the  external  air.  The  object  of  this  is  to  catch 
and  carry  away  any  water  which  may  come  from  any  leak  in  the  taps,  pipes, 
or  bath.  The  overflow  pipe  from  the  bath  should  be  at  least  two  inches  in 
diameter,  and  should  go  directly  into  the  external  air.  It  cannot  be  too 
strongly  urged  that  no  pipes  proceeding  from  the  bathroom  must  communi- 
cate directly  with  the  drains.  Any  draught  that  comes  up  the  various  pipes 
leaving  a  bathroom  may  be  prevented  by  providing  the  exit  orifice  with  a 
flapper. 

The  bath  and  its  pipes  are  usually  surrounded  by  a  wooden  casing  with  a 
door  so  arranged  that  the  pipes,  corks,  and  leaden  tray  can  be  easily  inspected. 
This  is,  on  the  whole,  the  best  arrangement,  for  it  is  very  difficult  to  clean 
away  all  the  dirt  which  collects  under  the  bath  if  it  is  exposed.  Some  metal 
baths  are,  however,  made  to  stand  on  claw  feet,  and  they  are  painted  on  the 
outside,  so  that  a  casing  is  not  necessary. 

BIBLIOGEAPHY 

(1)  Braun  :  Lehrbucli  cler  Balneotherapie.     5th  edit. :  edited  by  Fromm.     Berlin. 

(2)  Leichtenstern :    General  Balneotherapeutics     (vol.   iv.  Ziemssen's  Handbook  of 

General  Therapeutics.     Eng.  trans.    London,  1885-6). 

(3)  Winternitz  :  Hydrotherapeutics  (vol.  v.  Ziemssen's  Handbook  of  General  Thera- 

peutics.    English  trans.     London,  1885-6). 

(4)  Helfft:  Handbuch  der  Balneotherapie.     9th  edit.:  edited  by  Thilenius      Berlin 

1882. 

(5)  Durand-Fardel :  Traite  des  Eaux  minerales.     3rd  ed.     Paris,  1883. 

(6)  Easpe:  Heilquellen-Analysen  fiir  normale  Verhaltnisse,  und  zur  Mineralwasser- 

fabrikation  berechnet  auf  zehntausend  Thale.     Dresden,  1885. 

(7)  Macpherson :  Our  Baths  and  Wells.     3rd  ed.    London,  1888. 

(8)  De  la  Harpe  :  La  Suisse  balneaire  et  climat^rique.     Zurich,  1891. 

(9)  Hale  White  :  A  Text-book  of  General  Therapeutics.    London,  1889. 


THE  DWELLING 


BY 


P.   GOEDON    SMITH,   F.E.LB.A, 

AND 

KEITH  D.  YOUXG,  F.E.LB.A. 


THE   DWELLING 

Of  all  conditions  that  are  prejudicial  to  the  healthfulness  of  the  dwellings 
air  that  has  been  rendered  impure  is  the  most  productive  of  evil.  The  late 
Dr.  Edmund  A.  Parkes  has  truly  said  that  a  healthy  dwelhng  must  comprise 
the  following  five  conditions  : — 

1.  A  site  dry  and  not  malarious,  and  an  aspect  which  gives  light  and 
cheerfulness. 

2.  A  ventilation  which  carries  off  all  respiratory  impurities. 

3.  A  system  of  immediate  and  perfect  sewage  removal  which  shall  render- 
it  impossible  that  the  air  shall  be  contaminated  from  excreta. 

4.  A  pure  supply  and  proper  removal  of  water  by  means  of  which  perfect 
cleanliness  of  all  parts  of  the  house  can  be  insured. 

5.  A  construction  of  house  which  shall  insure  perfect  dryness  of  the 
foundations,  walls,  and  roof. 

It  will  be  observed  that  in  these  conditions  pm'ity  of  air,  and  in  that 
purity  must  be  included  cleanliness,  is  the  fundamental  principle  aimed  at. 
Notwithstanding  the  apparent  simplicity  of  these  principles,  and  the  obvious- 
ness of  the  necessity  for  each  and  all  of  them,  it  is,  unfortunately,  rare  to- 
find,  even  in  the  present  day,  a  dwelling  in  which  due  attention  has  been  paid 
to  them.  In  the  past,  neglect  of  these  principles  has  led  to  plague  and 
pestilence  to  an  extent  which  it  is  difficult  for  us  to  appreciate,  and,  were 
similar  neglect  to  exist  now,  when  the  population  is  so  far  more  numerous- 
and  dense  than  formerly,  who  can  conjecture  to  what  magnitude  the 
disastrous  results  of  such  neglect  might  attain  ?  We  are  reminded  every 
now  and  again  by  comparatively  small  local  outbreaks  of  disease,  of  the  neces- 
sity for  paying  due  attention  to  this  question  of  purity  of  air  and  cleanhness  ; 
but  how  can  we  estimate  what  would  be  the  results  were  such  a  plague  as 
that  which  visited  London  in  1665  permitted  to  get  firm  hold  of  the  London 
of  the  present  day,  with  its  five  millions  of  inhabitants  and  its  means  of 
almost  hourly  communication  with  all  the  large  towns  of  the  provinces  ? 

It  is  well  to  bear  in  mind  what  were  the  ravages  of  that  plague,  and  the 
rate  at  which  it  progressed.  Thomas  De-Laune  in  his  '  Memorials  of  London,' 
1681,  after  giving  accounts  of  many  other  pre\T.ous  plagues  and  epidemics, 
says : — 

In  the  beginning  of  May  (1665)  the  Bill  of  Mortality  mentions  nine  that  died  of  the 
plague,  and  decreased  the  next  week  to  three,  then  increased  to  fourteen,  next  to  seventeen, 
next  forty-three,  and  then  great  persons  began  to  retire  into  the  country.  In  Jane  the 
bill  increases  to  112,  next  168,  next  267,  next  470  ;  then  do  many  tradesmen  go  into  the 
country,  and  many  ministers  take  occasion  to  absent  themselves  from  their  charge.  In 
July  the  bill  rises  to  725,  then  to  1,089,  next  1,843,  next  to  2,010.  Now  most  parishes  are 
infected,  a  vast  number  of  houses  are  shut  up,  no  trade  at  all,  and  the  number  of  dying 
persons  still  increasing,  although  so  many  thousands  left  the  city.  In  August  the  bill 
rises  to  2,817,  next  3,880,  next  4,237,  and  then  6,102,  all  which  died  of  the  plague  besides 
other  diseases.  Now  there  is  dismal  sohtude  in  London  streets,  every  day  looks  with  the 
face  of  a  Sabbath,  observed  -with  greater  solemnity  than  it  used  to  be  in  the  city.  Shops 
are  shut  up,  very  few  walk  about,  so  that  grass  begins  to  spring  in  some  places.  A  deep 
silence  everywhere,  no  ratling  of  coaches,  &c.,  no  calling  in  customers,  no  London  crys,  no 
noise  but  dying  groans  and  funeral,  knells,  &g.    In  September  the  bill  rises  to  6,988,  the 


Go2  HYGIENE 

next  falls  to  6,544,  but  then  rises  again  to  7,165,  which  was  the  greatest  bill.  There  were 
but  four  parishes  that  were  not  infected,  and  in  them  few  tarried.  The  next  bill  falls  to 
5,538,  then  to  4,929,  then  to  4,327,  then  to  2,665,  then  to  1,421,  then  to  1,031.  First  week 
in  November  it  rises  to  1,414,  but  falls  to  1,050,  then  to  652,  then  to  333,  and  so  lessened 
more  and  more  to  the  end  of  the  year,  when  we  had  a  bill  of  97,306  which  died  of  all 
diseases,  which  was  79,000  more  than  the  year  before,  and  the  number  of  them  which  died 
of  the  plague  was  reckoned  to  be  68,596  that  year  ;  but  others  say  that  there  died  of  that 
fatal  disease,  in  little  more  than  a  year's  space,  near  100,000  persons  in  London  and 
some  adjacent  places. 

Such  was  the  penalty  paid  by  the  community  for  allowing  the  houses  to 
be  crowded  together,  wdth  narrow  and  crooked  alleys  and  passages  which 
served  as  streets,  to  which  sunshine  never  had  access,  and  which  did  not 
permit  of  proper  circulation  of  air  ;  for  failing  to  provide  any  efficient  means 
for  the  removal  of  the  filth  and  sewage,  which  remained  on  the  street  surface 
until  washed  away  by  rain  ;  and,  in  fact,  for  allowing  a  dense  city  to  grow  up 
without  any  efficient  control  in  its  growth  or  management. 

The  fearful  ravages  above  recorded,  however,  give  us  only  the  death-roll 
consequent  on  that  terrible  epidemic.  This  outbreak  of  plague  was  only  the 
culmination  of  a  long  series  of  shockingly  unhealthy  conditions  which  had 
previously  caused  repeated  outbursts  or  '  explosions,'  but  which  at  length 
developed  to  the  enormous  extent  set  forth  by  De-Laune.  These  preceding 
conditions  must  have  affected  the  general  health  of  the  population  to  a  degree 
which  it  is  impossible  to  estimate,  and  of  which  there  is  no  sort  of  record, 
direct  or  indirect. 

The  circumstances  mider  which  outbreaks  of  disease  occur  nowadays, 
terrible  as  they  appear  to  us,  are  very  different ;  even  the  occurrence  of  many 
cases  of  typhus  in  some  densely  crowded  quarter  of  a  town  is  a  small  matter 
compared  with  the  plagues  of  old,  which  ran  their  course  until  they  had 
literally  exhausted  the  supply  of  subjects  to  attack;  and  the  magnitude  of 
the  old  epidemics  is  now  rarely  approached,  notwithstanding  the  vastly 
increased  facilities  that  exist  for  the  spread  of  disease,  owing  to  growth  and 
intercommunication  of  the  population. 

The  lessons  that  have  been  taught  by  the  great  epidemics  in  the  past  in- 
dicate three  important  factors  in  regard  to  the  healthy  conditions  of  towns  : 
1.  That  there  must  be  wide  streets  with  frequent  cross  streets,  and  also 
ample  open  space  about  the  houses,  so  as  to  promote  the  free  circulation  of 
air.  2.  That  the  internal  arrangements  of  the  individual  houses  shall  be 
such  as  's\ill  conduce  to  their  efficient  ventilation  and  to  the  purity  of  the 
air  inside  them.  3.  That  the  administration  of  the  town  shall  be  such  as 
to  ensure  the  unstinted  supply  of  pure  and  wholesome  water,  the  effectual 
removal  of  all  sewage  and  liquid  refuse,  and  the  regular  and  thorough 
scavenging  and  removal  of  refuse.  These  three  conditions  are  requisite 
wherever  a  few  dwellings  are  clustered  together. 

That  they  have  been  generally  seriously  neglected  is  evident  in  all  parts 
of  the  kingdom,  and  the  results  are  demonstrated  by  the  unhealthy  condi- 
tions that  so  frequently  form  the  subject  of  official  investigation  either 
by  the  local  health  officers  or  by  the  inspectors  of  the  medical  department 
of  the  Local  Government  Board.  As  regards  the  first,  the  results  of  past 
neglect  of  control  in  the  laying  out  of  towns  is  demonstrated  by  the  vast 
expenditure  of  money  that  in  recent  years  many  local  authorities  have 
found  themselves  compelled  to  incur  for  the  acquisition,  under  statutory 
powers,  of  extensive  areas  of  insanitary  properties  in  order  that  the  build- 
ings may  be  demolished,  and  that  new  streets  of  greater  width  may  be  laid 
out,  and  new  houses  having  adequate  air  space  about  them  may  be  erected. 
In  this  way  millions  of  pounds  sterling  have  in  the  last  thirty  or  forty  years 


THE  DWELLING  653 

been  spent  in  the  metropolis  and  in  some  of  the  principal  towns  of  the  pro- 
vinces. In  many  districts  of  London  where  houses  were  huddled  together  in 
the  closest  possible  fashion,  and  contained  populations  of  great  density,  areas 
have  been  cleared  and  comparatively  broad  streets  with  improved  buildings 
have  been  erected  on  them.  In  the  same  way  in  Liverpool,  in  Birmingham, 
in  Newcastle-on-Tyne,  in  Leeds,  and  elsewhere,  similar  improvements  have 
been  made  ;  and  although  in  some  respects,  as  will  be  described  later  on, 
these  changes  leave  much  to  be  desired,  they  nevertheless  have  exercised  a 
very  marked  improvement  on  the  health  conditions  of  the  localities. 

The  way  in  which  some  of  these  insanitary  areas  were  allowed  to  grow 
up  is  not  without  its  special  interest,  and  the  study  of  the  growth  of  such 
areas  ought  to  teach  a  lesson  worthy  of  application  in  numbers  of  towns  now 
growing  rapidly  in  size  and  population,  and  which,  indeed,  may  perhaps  not 
grow  to  be  quite  so  bad  as  some  of  the  places  already  referred  to,  but  which 
are  most  certainly  allowing  a  very  unwholesome  aggregation  of  houses  and 
population  to  occur,  and  cannot  fail  to  involve  serious  difficulty  and  ex- 
pense in  the  future.  This  growth  of  unhealthy  areas  may  be  seen  in  most 
of  our  larger  towns  and  in  many  of  the  smaller  ones  and  even  in  many 
villages,  while  at  numbers  of  seaside  '  health  resorts '  the  process  of  crowd- 
ing houses  on  area  has  been  going  on  until  within  quite  recent  years,  and  in 
others  it  is  still  going  on. 

Thus  one  may  see  in  streets  of  very  modest  width  rows  of  what  were 
once  convenient  houses  originally  built  for  single  families,  and  had  a  good 
depth  of  garden  at  their  rear.  These,  owing  to  the  altered  character  of  the 
neighbourhood  or  local  changes  in  trade  or  manufacture,  have  come  to  be 
occupied  by  many  families  in  each  house  ;  narrow  passages  or  courts  have 
been  formed  at  intervals  through  the  gromid  storey  in  order  to  give  access 
to  blocks  of  smaller  houses  that  have  been  built  on  the  garden  ground  at 
the  rear,  and  in  between  these  have  been  wedged  the  scanty  privy  and  ash- 
pit accommodation  for  the  dense  population  now  occupying  the  area.  In 
the  older  parts  of  many  watering  places,  which  during  the  summer  months 
are  crowded  with  visitors,  so  that  the  population  is  trebled  or  quadrupled,  it 
will  be  found  that  the  yard  originally  left  at  the  rear  of  many  of  the  houses 
is  almost  wholly  obstructed  by  a  smaU  house  which  has  been  built  in  it,  to 
which  the  proprietor  retires  during  the  letting  season  in  order  that  the  main 
house  may  be  freed  for  the  occupation  of  the  visitors ;  and  thus  the  smaller 
backhouse  has  no  means  of  through -ventilation  whatever,  and  only  a  small 
and  confined  well  of  stagnant  air  in  front  of  it,  which  also  has  to  serve  as  the 
open  space  at  the  rear  of  the  front  main  house. 

The  reports  of  the  Medical  Officer  of  the  Privy  Council  and  Local 
Government  Board  refer  to  many  instances  tending  to  show  that  crowding 
of  houses  on  area  and  corresponding  density  of  population  are  attended  with 
endemic  and  epidemic  disease.  Thus  in  the  report  ^  by  Dr.  George 
Buchanan  on  epidemic  typhus  at  Greenock,  in  1865,  it  is  shown  that 
Greenock  had  an  excessively  high  general  death-rate,  due  to  a  large  extent 
to  the  deaths  of  children,  as  YfeM  as  to  special  fatality  of  lung  diseases  and 
consumption,  and  likewise  to  the  then  recent  epidemic  prevalence  of 
measles,  scarlatma,  smallpox  and  diphtheria,  each  of  which  diseases  had 
affected  the  town  with  exceptional  intensity.  The  cause  of  the  great 
epidemic  prevalence  of  fever  was  attributed  entirely  to  overcrowaing  and  the 
dirty  habits  of  the  people,  little  or  no  influence  being  ascribed  to  defects  of 
drainage,  and  any  exceptional  destitution  being  at  that  time  wholly  wanting 

'  See  Eighth  Ammal  Report  of  the  Medical  Officer  of  the  Privy  Council,  Appendix, 
p.  209. 


654  HYGIENE 

as  a  causative  element.  The  crowding  of  tenement  houses  on  area  is 
described  in  that  report  as  prevailing  to  a  remarkable  extent  in  the  old  part 
of  Greenock,  every  particle  of  ground  that  was  not  street  being  covered  with 
buildings.  It  is  said  that  some  air  trickles  between  the  tops  of  the  tenements 
and  may  get  into  the  upper  tenements,  but  in  not  a  few  of  the  lower  ones 
the  back  rooms  receive  no  breath  of  air  or  ray  of  light.  The  description 
given  of  the  crowding  of  persons  within  the  houses  is  even  more  striking. 

It  is  remarkable  how  this  crowding  of  population  on  area  has  grown  up 
in  the  course  of  centuries ;  comparatively  speaking,  very  few  new  towns 
have  sprung  up,  and  nearly  every  town  and  village  throughout  the  land  owes 
its  origin  to,  and  indeed  has  some  sort  of  evidence  in  proof  of  its  existence  in 
the  time  of  the  Eomans,  the  Saxons,  or  the  Normans  ;  thus,  even  in  those 
days,  the  country  was  studded  with  villages  lying  between  the  greater  towns, 
and  many  of  these  have  since  grown  to  be  chief  provincial  towns  or  cities,  the 
growth  of  which  has  been  partly  circumferential,  but  m  a  large  degree  caused 
by  the  closer  packing  together  in  the  centres.  This  is  shown  in  a  very  clear 
manner  in  one  of  the  annual  reports  of  the  Medical  Officer  of  the  Local 
Government  Board. ^  In  anticipation  of  the  country  being  visited  by  cholera, 
the  Board  caused  a  sanitary  survey  to  be  made  of  the  coast  towns  where 
cholera  might  be  imported  from  infected  countries  and  of  a  large  number  of 
other  towns  where  it  was  known  that  other  diseases  spreading  under  some- 
what similar  circumstances  to  cholera — e.g.  enteric  fever  or  epidemic 
diarrhoea — habitually  prevail.  In  this  survey  special  attention  was  directed 
to  the  general  condition  of  the  dwellings  of  the  poor  and  labouring  classes, 
and  specially  to  the  prevalence  of  crowding  of  dwellings  on  area  as  well  as 
of  overcrowding  within  dwelhngs.  The  tabulated  precis  of  the  reports  upon 
the  various  places  surveyed  showed  some  striking  instances  of  crowding  of 
houses  on  area  about  narrow  courts  and  streets ;  and  this  notably  in  the 
cathedral  and  university  towns. 

The  provision  of  ample  open  space  in  our  towns  in  the  form  of  wide 
streets,  cross  streets  at  frequent  intervals,  public  squares,  boulevards,  and 
parks  and  gardens  within  easy  reach  of  the  inhabitants,  especially  the 
children,  where  they  can  assemble  in  the  open  air  for  exercise  and  recreative 
purposes,  has  in  the  past  failed  to  receive  as  much  attention  in  the  laying 
out  of  districts  as  it  deserves.  In  some  of  the  large  proprietary  estates  of 
London — e.g.  the  Grosvenor,  the  Penton,  the  Bedford,  the  Portland,  and  the 
Portman  Estates — some  splendid  squares  and  streets  have  been  formed, 
which  have  been  of  enormous  benefit  to  the  inhabitants,  and  in  a  scarcely  less 
degree  to  the  public  ;  but  wherever  the  land  has  been  in  the  hands  of  small 
owners  it  has  been  subject  to  all  the  disadvantages  of  the  numerous  indivi- 
dual interests  ;  and,  in  the  total  absence  of  any  legislative  requirements, 
improvement  of  this  kind  has  been  impracticable. 

Such  open  areas  as  have  just  been  referred  to  are  as  indispensable  in  their 
way  in  our  towns  and  cities  as  are  the  open  spaces  now  commonly  required 
about  individual  houses,  and  yet  no  laws  have  hitherto  been  framed  for  making 
the  provision  of  them  compulsory.  Some  slight  efforts  have  been  made  in  recent 
years  to  increase  the  voluntary  provision  of  open  space  in  thickly  populated 
areas  ;  thus,  for  the  metropolis,  the  MetropoHtan  Open  Spaces  Acts  of  1877 
and  1881  have  given  facihties  for  the  acquisition,  maintenance,  and  regulation 
of  open  spaces  and  burial  grounds  by  the  local  authorities  of  the  metropolis 
for  the  use  of  the  public  for  exercise  and  recreation,  and  authorise,  for  the 

'  Fifteenth  Annual  Report  of  the  Local  Government  Board,  1885-86.  Supplement 
containing  [c.  4873]  '  Eeports  and  Papers  on  Cholera  submitted  by  the  Medical  Officer  of 
the  Board.' 


THE  DWELLING 


655 


purposes  of  those  Acts,  the  expenditure  of  such  funds  as  those  authorities 
have  at  their  disposal.  Similar  facilities  for  making  open  spaces  and  burial 
grounds  situated  in  the  provinces  available  for  the  like  use  by  the  public 
are  also  afforded  by  the  Open  Spaces  Act,  1887,'  which  latter  Act  has 
amended  the  previous  Acts  in  several  particulars,  and  has  rendered  most 
of  the  amended  provisions  of  those  Acts  applicable,  with  the  necessary 
modifications,  to  every  urban  and  rural  sanitary  district  in  England  and  > 
Wales.  Under  these  Acts  powers  are  given  to  local  authorities  to  acquire, 
either  by  purchase  or  gift,  and  to  trustees  and  other  persons  and  corpora- 
tions under  disability  or  possessing  limited  interest,  to  transfer  open  spaces 
and  disused  burial  grounds  to  the  sanitary  authorities  in  order  that  they  may 
be  held  in  trust  and  maintained,  and  if  necessary  be  laid  out  and  improved 
with  a  view  to  their  enjoyment  by  the  public  in  an  open  condition,  free  from 
buildings  and  under  proper  control  and  regulation. 

These  Acts  should  be  constantly  borne  in  mind  by  local  sanitary  authori- 
ties and  their  officers,  especially  in  districts  where  the  population  is  rapidly 
increasing  and  the  ground  is  being  speedily  covered  with  buildings,  in  order 
that  a  due  amount  of  open  space,  over  and  above  what  is  afforded  by  streets 
of  ordinary  width,  may  be  secured  to  the  public  at  a  time  when  it  can  be 
acquired  without  much  difficulty  and  before  the  erection  of  houses  over  the 
whole  district  renders  the  acquisition  of  such  open  space  practically  im- 
possible. The  provision  of  open  space  for  the  use  of  the  public  ought  of 
course  to  be  made  with  due  regard  to  its  equable  distribution  over  the  popu- 
lation, since  the  greatest  benefit  would  result  from  its  proximity  to  the 
several  parts  of  the  districts.  Hence,  a  broad  boulevard  all  round  a  town  or 
directly  through  it  would  be  one  of  the  most  useful  forms  of  open  space ;  or, 
again,  a  number  of  open  squares  situated  in  different  parts  of  a  town  would 
be  of  more  general  use  than  a  single  park  of  even  large  extent  situated  at 
one  end  of  the  same  town.  If,  when  a  town  aspires  to  be  incorporated  as  a 
borough,  it  were  required,  as  a  condition  of  its  promotion,  to  acquire  and  set 
apart  for  the  use  of  the  public  a  certain  extent  of  land  as  open  space  for 
exercise  and  recreative  purposes,  what  vast  benefits  would  result  to  the 
inhabitants !  It  may  be  difficult  to  lay  down  any  proportion  of  area  to 
population  as  a  minimum,  but  a  comparison  with  what  exists  in  certain 
towns  and  cities  would  serve  as  some  sort  of  guide  to  assist  in  considering 
what  might  be  fairly  demanded.^     Much  is  undoubtedly  being  done  in  the 

»  50  &  51  Vict.  cap.  32. 

2  The  number  of  persons  per  acre  of  open  space  is  given  by  E.  E.  L.  Gould  in  the 
publications  of  the  American  Statistical  Association  as  follows : — 

A  B 

In  London      .        .        .694        909 

Paris  .        .        .495        985 

Berlin         .        .        .804      1,814 

Edinburgh.         .         .     246         672 

Vienna       .        .        .473      3,805 

Manchester         .         .2,230        — 

New  York  .        .        .994     8,334 

The  figures  in  column  A  hardly  give  an  accurate  notion  of  the  proportion  of  open  space 

which  the  inhabitants  of  the  several  cities  and  towns  really  enjoy,  partly  because  of  the  great 

differences  in  the  width  of  streets,  and  partly  because  of  the  differences  in  the  way  in 

which  the  open  space  is  distributed.   Accordingly,  column  B  is  introduced  in  which  thearea 

of  the  largest  distinct  park  in  each  city  or  town  has  been  omitted,  and  the  result  shows  in 

some  instances  a  vastly  increased  number  of  persons  to  the  acre.     But  as  regards  absolute 

proportion  of  open  space  to  population,  Washington  appears  to  be  far  ahead  of  any  large 

city  in  the  world,  and  it  has  also  the  greatest  relative  number  of  small  open  spaces — Tlw 

Sanitary  Engmeer,  New  York,  Jan.  5,  1889. 


A 

B 

Boston  . 

.    301 

529 

Baltimore 

.    376 

1,749 

Philadelphia 

.     340 

17,649 

Cincinnati 

.     678 

1,528 

St.  Louis 

.     164 

460 

Washington 

.     361 

451 

656  HYGIENE 

way  of  providing  open  spaces.  The  acquisition  of  various  areas  in  the 
suburbs  of  London  is  a  most  valuable  pro\'ision  for  the  public  good,  the 
magnificent  roads  that  are  being  formed  in  some  districts — e.g.  that  in  the 
Toxteth  Park  district  at  Liverpool  leading  out  to  Princes  Park — all  show 
that  the  necessity  for  open  spaces  is  recognised,  but  much  still  remains 
to  be  done,  and  the  public  have  to  be  led  to  understand  the  necessity  for  it. 

The  question  of  density  of  population  is  one  that  cannot  properly  be  over- 
looked in  connection  with  the  hygiene  of  the  dwelling.  It  has  been  affirmed 
that  the  density  of  population  affords  no  index  of  the  death-rate,  but,  not- 
withstanding, it  is  shown  in  the  annual  reports  of  the  Kegistrar-General  that 
the  highest  death-rates  occur  in  the  most  densely  populated  areas,  and  that 
infant  mortality  in  general,  and  diarrho3a  in  particular,  prevail  wherever  there 
is  great  aggregation  of  population.  Doubtless  this  is  to  some  extent  to  be 
accounted  for,  partly  by  the  social  habits  of  the  people  themselves  and  partly 
by  defective  local  administration,  such  as  improper  scavenging  and  insuf- 
ficient water  supply,  but  perfection  of  these  matters  will  not  alone  suffice  to 
place  the  sanitary  state  of  a  densely  populated  area  in  the  same  condition  as 
an  equally  well-cared-for  area,  where  the  population  is  sparsely  distributed. 
Where  there  is  considerable  density  of  population,  it  follows  that  the  houses 
must  be  packed  very  closely  together,  that  the  rooms  must  be  occupied 
by  numbers  of  persons  approaching  what  is  known  as  '  overcrowding,'  and 
that  the  houses  may  even  be  of  excessive  height  in  proportion  to  the  open 
space  about  them.  According  to  the  minimum  open  space  about  houses  re- 
quired by  the  Model  Bye-laws  of  the  Local  Government  Board,  the  largest 
number  of  water-closeted  cottage  dwellings  that  can  be  got  on  an  acre  of 
land  is  forty-eight  when  each  house  has  a  frontage  of  14  ft.  9  in.  and  con- 
tains a  living  room  and  scullery  m  the  ground  storey,  two  bedrooms  in  the 
upper  storey,  and  an  attic  room,  and  if  privies  are  substituted  for  water-closets, 
and  the  requisite  back  streets  are  provided  for  the  removal  of  ashes  and 
privy  refuse,  the  number  of  similar  houses  would  be  only  forty-one  or  forty- 
five,  according  to  the  width  of  the  back  street.^  Supposing  that  each  of  these 
houses  is  occupied  by  an  average  of  five  persons,  the  density  of  population 
would  be  represented  by  a  rate  of  240  persons  to  the  acre  in  the  former 
instance,  and  from  205  to  225  to  the  acre  in  the  latter  instance. 

In  some  of  the  blocks  of  artisans'  dwellings  that  have  been  erected  in  the 
metropolis  this  rate  is  very  largely  exceeded.  Thus,  from  the  evidence  given 
in  1884  before  the  Koyal  Commission  on  the  Housing  of  the  Working  Classes 
the  density  of  population  is  stated  to  be,  in  some  instances,  at  the  rate  of  about 
1,000  persons  to  the  acre,'^  and  the  health  of  the  inhabitants,  judged  by  the 
mortahty  statistics,  is  stated  to  be  satisfactory.  In  these  instances  the 
buildings  were  designed  to  be  six  storeys  in  height,  and,  notwithstanding 
certain  objections  raised  by  the  Home  Office  to  their  great  height,  those 
objections  were  ultimately  waived,  and  a  height  of  six  storeys  eventually 
became  the  rule,-^  and  even  this  has  since  been  exceeded.  In  some  instances, 
however,  these  buildings  were  so  crowded  on  the  area  that,  owing  to  their 
height,  to  the  limited  amount  of  open  space  in  the  internal  court  or  '  play- 
ground '  and  about  the  exterior,  to  the  absence  of  openings  at  the  angles  of 
the  court,  and  of  sufficient  openings  from  the  court  into  the  adjacent  streets, 
there  were  serious  impediments  to  the  access  of  sunsliine  and  to  free  circula- 
tion of  air  about  them,  with  the  result  that  the  health  conditions  of  those 
particular  buildings,  though  the  fittings  and  details  of  construction  were 

'  Report  on  Back-to-back  Houses.  By  Dr.  Barry  and  Mr.  P.  Gordon  Smith.  London  : 
Eyre  &  Spottiswoode,  1888. 

-  Q.  11812  and  1181:3.  ^  q.  11348. 


THE  DWELLING  667 

identical  with  those  of  other  more  healthy  buildings,  were  reported  to  be  far 
worse  than  others,  the  rate  of  infant  mortality  specially  being  much  higher 
in  them  than  elsewhere. 

In  the  recent  report  to  the  Local  Government  Board  by  Dr.  Ballard  upon 
the  causation  of  the  annual  mortality  from  diarrhoea  '  he  points  out,  among 
the  more  important  conditions  influencing  diarrhoeal  mortality,  that  aggrega- 
tion of  population  favours,  and  dispersion  over  area  disfavours,  diarrhoea ; 
that  density  of  buildings  (whether  dwelling-houses  or  other)  upon  area  pro- 
motes diarrhoeal  mortality  ;  and  that  restriction  of  and  impediments  to  the 
free  circulation  of  air,  both  about  and  within  dwellings,  promote  diarrhoeal 
mortality.  There  are,  it  must  be  admitted,  many  strong  reasons  for  allowing, 
in  some  cases,  considerable  aggregation  of  population  on  area,  and  within 
certain  limits  and  under  certain  conditions  as  regards  local  administration, 
it  may  be  permissible,  in  such  cases,  to  approach,  though  scarcely  to  reach, 
the  very  high  rate  of  density  above  referred  to.  But  it  appears  certain  that 
high  rates  of  density  cannot  be  allowed  with  impunity,  and  that  some  limit 
must  be  determined  upon.  Overcrowding,  in  the  form  of  an  abatable  nui- 
sance, has  a  statutory  limitation  to  an  individual  house  or  part  of  a  house, 
and  the  only  way  by  which  such  vast  numbers  can  be  aggregated  on  area 
is  by  piling  up  houses  one  upon  another  in  the  form  of  tenements,  and  so 
long  as  the  height  to  which  buildings  may  be  carried  remains  unlimited 
by  law,  this  method  of  providing  house  accommodation  will  go  on  extend- 
ing. A  single  building  of  abnormal  height  here  and  there  may,  in  itself, 
be  of  little  harm ;  but  when  repeated  in  near  proximity  one  to  another 
the  conditions  would  become  serious.  At  least,  some  means  ought  to  be 
found  for  securing  adequate  open  space  about  every  such  high  building. 
This  would  not  only  suffice  for  securing  freer  circulation  of  air  about  the 
dwellings,  but  it  would  at  the  same  time  have  the  effect,  indirectly,  of  placing 
some  moderate  restrictions  on  the  number  of  persons  to  be  provided  for  on 
any  given  area.  In  the  recommendation  of  the  Housing  of  the  Working  Classes 
Committee  of  the  London  County  Council,  which  was  adopted  by  the  Council 
at  the  end  of  1889,  it  is  suggested  that  the  distance  between  any  block  of 
dwellings  and  the  nearest  building  obstructing  the  light  from  its  windows 
should,  if  practicable,  be  equal  to  one  and  a  half  times  the  height  of  the 
obstructing  building.  But  it  is  anticipated  that,  in  view  of  the  cost  of  land 
in  the  metropolis,  such  distance  cannot  be  generally  provided.  It  is,  how- 
ever, laid  down  that  '  under  no  circumstances  should  a  nearer  distance  than 
the  height  of  the  buildings  be  allowed.'  It  remains  to  be  seen  how  far  even 
this  modification  of  what  is  considered  most  desirable  can  be  complied  with. 
That  it  is  an  excellent  rule  in  the  interest  of  health  can  scarcely  be  ques- 
tioned, but  the  difficulties  of  strictly  adhering  to  it  where  questions  of  finance 
occur  appear  to  be  almost  if  not  quite  insuperable. 

In  reviewing  the  dwelling  accommodation  of  the  population  of  such  a 
country  as  the  United  Kingdom,  it  will  be  found  that  it  may  be  classified 
somewhat  as  follows  :— 1.  There  are  the  mansions  and  large  houses  of  the 
nobility  and  wealthy,  studded  all  over  the  country  and  in  the  best  parts  of 
the  metropolis.  2.  Then  there  are.  the  smaller  houses  and  villa  residences 
of  the  so-called  middle  classes,  occupying  perhaps  equally  good  positions  but 
much  smaller  areas  of  site.  3.  Next  to  these,  and  scarcely  differing  in  ac- 
commodation, are  the  terrace  houses  of  the  same  class,  clustered  more  closely 
together,  as  most  of  the  occupiers  of  them  have  to  be  within  a  certain  limited 
distance  from  some  neighbouring  locality  or  place  of  business.     4.  Closely 

'  London  :  Eyre  &  Spottiswoode,  1889.     [c. — 5638.] 
VOL.  I.  U  U 


G58  HYGIENE 

allied  to  these  is  the  class  of  dwelling  combined  with  place  of  business.  5. 
The  next  kind  of  dwelling  is  the  small  house  or  cottage  of  the  artisan  and 
wage-earning  community — perhaps  the  most  numerous  of  all — which  varies, 
as  in  the  other  kinds  of  dwelling,  according  to  locality  and  circumstances. 
6.  Lastly  there  is  the  institution  in  which  is  housed  a  greater  or  less  number  of 
persons  who  are  gathered  within  its  walls  for  some  common  purpose  or  object. 

Each  of  these  several  kinds  of  dwellings  is  necessarily  subject  to  numerous 
modifications,  many  of  which  must  be  considered  distinctly  under  their  various 
heads.  Thus  in  the  case  of  the  first  class — mansions — must  be  included  the 
palaces  of  Royalty  and  of  the  nobility,  the  magnificent  mansions  and  extensive 
dwellings,  with  their  dependencies,  both  in  town  and  country,  of  the  merchant 
princes  and  wealthy  manufacturers.  The  second  class  embraces  not  only  the 
suburban  and  country  house  of  the  ordinary  professional  man  of  business  and 
wealthy  tradesman,  whether  retired  or  still  in  business,  but  the  country  par- 
sonage and  the  residence  of  the  well-to-do  farmer  together  with  the  out- 
buildings connected  therewith.  The  third  class  is  more  essentially  urban, 
and  is  chiefly  concerned  with  that  vast  section  of  the  so-called  middle  class 
of  the  commmiity,  whether  professional,  clerical,  or  commercial,  who  are 
compelled  to  live  in,  or  in  the  immediate  neighbourhood  of,  towns,  where  land 
is  too  valuable  to  admit  of  the  houses  having  more  than  is  requisite  for  them 
to  stand  on,  with  a  small  amount  of  open  space  in  front  and  at  their  rear.  It 
must  likewise  include  what  have  come  to  be  known  as  '  flats.'  The  fourth 
class  embraces  the  dwelling  in  connection  with  the  place  of  business  such 
as  the  ordinary  shop  premises  with  dwelling  apartments  above,  also  the 
hotel,  inn,  and  such  like.  The  fifth  class  is  by  far  the  most  numerous, 
and  the  modifications  of  it  are  very  varied.  Thus,  it  must  include  the 
agricultural  labourer's  cottage  in  the  country  and  the  artisan's  cottage  in 
the  manufacturing  town,  the  tenement  house  in  the  block  of  artisans'  dwel- 
lings, the  common  lodging-house,  and  the  accommodation  let  out  to  lodgers 
generally,  including  what  are  known  as  '  cellar  dwellings.'  The  sixth  class — 
institutions — must  include  residential  schools,  barracks,  asylums,  work- 
houses, prisons,  hospitals,  &c. 

The  extraordinary  increase  of  population  that  has  taken  place  in  recent 
times  throughout  the  country,  and  most  of  all  in  the  urban  parts,  has  neces- 
sitated the  erection  of  vast  numbers  of  new  houses.  There  is  apparently 
much  difference  in  the  numbers  erected  year  by  year  in  the  various  localities, 
caused  no  doubt  by  the  variations  in  trade  and  prosperity  as  well  as  by  a 
variety  of  local  circumstances,  but  the  numbers  generally  are  very  considerable. 
According  to  the  census  returns  for  England  and  Wales,  there  was  a  large 
increase  in  the  number  of  inhabited  houses  during  the  ten  years  ending  April 
1891,  the  total  number  of  such  houses  in  April  1881  having  been  4,831,519, 
and  in  April  1891,  5,460,976,  or  an  increase  of  13  per  cent.  There  were  also 
at  the  date  of  the  census  1891,  380,117  unoccupied  houses  and  38,407  in 
course  of  erection  ;  but  these  numbers  were  somewhat  lower  than  at  the  date 
of  the  previous  census.  In  the  Metropolitan  Police  District,  inclusive  of  the 
city,  with  its  population  (1891)  of  5,633,332,  there  are  797,679  inhabited 
houses,  and  these  have  increased  during  each  of  the  decennial  periods  ending 
1871,  1881,  and  1891  by  93,504,  117,661,  and  151,984  respectively.  These 
large  figures  will  be  more  readily  appreciated  when  it  is  realised  that  they 
mean  that  during  the  first  of  those  three  periods  an  average  of  thirty-one 
new  houses  were  finished  in  the  Metropolitan  Police  District  on  every  working 
day  ;  during  the  second  period  thirty-eight  new  houses  were  so  completed  ; 
and  during  the  third  period  as  many  as  forty-nine  new  houses  were  completed, 
on  the  average,  on  every  working  day  of  the  ten  years. 


THE  DWELLING  659 

It  will  be  seen  that,  according  to  the  census  1891,  the  average  number  ol' 
persons  in  every  inhabited  house  was  7"6,  but  by  far  the  larger  proportion  of 
these  new  houses  are  houses  intended  for  artisans  and  the  wage-earning 
classes,  which  let  at  weekly  rents  ranging  between  five  and  eight  or  ten 
shillings  a  week,  or  at  yearly  rentals  of  about  20Z.  to  30L  or  35L,  and  in 
which  the  average  number  of  inhabitants  is  probably  between  four  and  five 
per  house. 

Whatever  the  class,  there  are  certain  indispensable  conditions  of  con- 
struction that  are  common  to  every  dwelling,  be  it  a  palace,  a  labourer's 
cottage,  or  an  institution  in  town  or  country  alike,  if  it  is  to  be  such  as  may 
be  regarded  as  healthy.  Thus  it  must  be  so  constructed  as  to  be  able  to  be 
kept  free  from  damp,  to  be  proof  against  weather  and  excesses  of  temperature 
-or  sudden  external  changes,  and  to  maintain  the  air  within  it  in  a  proper 
a,nd  wholesome  condition.  These  indispensable  conditions  have  for  the  most 
part  been  dealt  with  in  more  or  less  detail  in  the  Model  Bye-laws  as  to  new 
buildings  ^  which  were  issued  by  the  Local  Government  Board  in  1877  for  the 
^■uidance  of  sanitary  authorities  when  framing  building  regulations  for  their 
districts,  and  comprise  the  following  provisions: — {a)  the  site  of  the  dwelling 
must  be  free  from  offensive  soil,  and  the  surface  of  the  ground  enclosed  within 
the  walls  of  the  building  must  be  covered  with  a  layer  of  good  cement  concrete 
in  order  to  exclude  any  sort  of  ground  air  from  the  building  ;  (&)  the  external 
walls  must  be  of  suitable  material  and  of  adequate  thickness  and  construction 
such  as  will  effectually  keep  out  the  weather  and  afford  reasonable  means  of 
preserving  to  the  interior  of  the  dwelling  a  suitable  temperature  ;  (c)  the 
whole  of  the  walls  of  the  dwelhng,  whether  external  walls,  party  walls,  in- 
ternal cross  walls,  or  sleeper  walls  supporting  the  flooring  of  the  lowest  storey, 
must  have  an  adequate  and  efficient  damp-proof  course  to  prevent  moisture 
rising  in  them  by  capillary  attraction ;  {cl)  the  roof  must  be  thoroughly 
weather-tight,  and  ought  to  be  of  such  construction  as  will  effectually  serve  to 
protect  the  interior  of  the  dwelling  not  only  from  rain,  hail,  and  snow,  but 
from  external  heat  and  cold  ;  (e)  the  means  of  light  and  ventilation  throughout 
the  dwelling  must  be  adequate  and  effectual ;  (/)  the  means  of  removing 
waste  water,  sewage,  and  refuse  of  every  description  must  be  cleanly,  regular, 
and  speedy,  and  such  as  will  not  in  any  way  be  prejudicial  to  the  health  con- 
ditions of  the  dwelling  ;  {g)  the  means  of  supplying,  storing,  and  distributing 
water  must  be  such  as  will  secure  an  unstinted  supply,  and  will  not  allow 
its  quality  to  be  impaired. 

It  may  be  useful  here  to  refer  briefly  to  the  details  of  these  several  indis- 
pensable conditions  in  order  that  the  necessity  for  them  as  well  as  their  full 
advantage  may  be  duly  appreciated  and  understood. 

The  first  of  them  [a)  relates  to  the  protection  of  the  interior  of  the  dwel- 
ling from  exhalations  from  the  ground  upon  which  it  is  built. 

If  a  site  has  been  artificially  made,  the  greatest  care  is  necessary  to  ascer- 
tain that  the  subsoil  is  free  from  any  organic  matter  in  a  state  of  decompo- 
sition. Sites  are  dealt  with  by  the  enterprising  speculating  builder  in  a 
remarkable  manner.  In  some  districts  much  profit  is  made  out  of  the  site 
before  any  building  is  put  upon  it :  thus,  the  turf  is  first  sold,  then  the  sur- 
face ground  is  disposed  of  for  garden  purposes  ;  the  subsoil  is  then  excavated, 
sometimes  for  sand  or  gravel,  which  always  has  a  good  market  value,  some- 
times for  stone,  and  sometimes  for  clay  with  which  bricks  are  manufactured 
or  which  is  burnt  for  ballast.  The  site  is  then  used  as  a  tip  for  rubbish  ol 
all  kinds,  a  small  fee  being  charged  for  each  load  that  is  deposited  upon  it ; 

»  The  Model  Bye-laics  of  the  Local  Government  Board.     London :  Knight  &  Co. 

D  u2 


6C0  HYGIENE 

and  when  its  level  is  raised  to  a  suitable  height,  it  is  regarded  as  ready  for  use 
as  a  building  estate.  It  will,  therefore,  be  obvious  that  in  the  majority  of 
such  instances  the  materials  deposited  on  the  site  are  such  as  would  be 
likely  to  become  a  source  of  danger  to  the  healthiness  of  any  dwelling  that 
might  be  erected  thereon.  Hence  in  all  well-regulated  districts  it  is  required 
under  the  local  building  bye-laws  that  all  materials  impregnated  with  either 
faecal  matter  or  with  animal  or  vegetable  matter  should  be  removed  by  exca- 
vation or  otherwise  from  any  such  site  before  any  new  dwelling  is  erected 
upon  it.  This  may  invols'e  much  cost  and  labour  in  excavation,  but  if  a 
sufficient  len-gth  of  time  has  elapsed  since  the  objectionable  material  was 
deposited  on  the  site,  the  objection  may  possibly  have  been  removed  by  the 
ordinary  process  of  decay.  On  this  particular  question  some  very  interesting 
experiments,  having  for  their  object  to  ascertain  what  the  effect  of  time  had 
been  on  the  organic  matters  which,  together  with  cinder  refuse,  had  been 
used  to  fill  up  inequalities  in  the  ground,  were  made  by  Professor  Burdon 
Sanderson,  M.D.,F.R.S.,  and  the  late  Professor  Parkes,  M.D.,F.R,S.,  during  an 
investigation  some  few  years  ago  into  the  sanitary  condition  of  Liverpool, 
and  in  their  report  it  is  stated  that  '  the  process  of  decay  of  all  the  most 
easily  'destructible  matters,'  including  vegetable  refuse,  'is  completed  in 
three  years,'  while  in  the  case  of  wood  and  woollen  cloth  the  process  was 
more  prolonged.  It  is  further  stated  that  '  the  vegetable  and  animal  matter 
contained  in  the  cinder  refuse  decays  and  disappears  in  about  three  years,  and 
is  virtually  innocuous  before  that  time.'  In  view  of  these  statements  it  may, 
therefore,  be  assumed  that  for  practical  purposes  three  years  will  amply  suffice 
for  the  removal  by  oxidation  of  the  objectionable  matters  in  such  refuse.  If, 
however,  faecal  matter  has  at  any  time  formed  part  of  the  refuse,  more  strin- 
gent precautions  ought  obviously  to  be  taken ;  indeed,  under  such  circum- 
stances, unless  all  soil  so  contaminated  were  completely  removed,  a  much 
longer  period  should  be  permitted  to  elapse  before  building  operations  could 
safely  be  allowed  to  commence. 

As  regards  the  necessity  for  covering  the  site  of  a  dwelling  with  concrete, 
the  sanitary  advantages  of  this  precaution  are  far  more  considerable  than  is 
commonly  supposed,  while  the  extra  cost  involved  by  it  may  be  less  appre- 
ciable than  at  first  sight  appears  to  be  the  case.  Dr.  Geo.  Buchanan,  F.E.S., 
in  his  report  on  the  distribution  of  phthisis  as  affected  by  dampness  of  soil,' 
has  shown  that  wetness  of  soil  is  a  cause  of  phthisis  to  the  population  living 
upon  it,  and  it  has  long  been  kno>vn  that  residence  on  a  damp  subsoil  as  the 
foundation  for  a  house  favours  the  prevalence  of  pulmonary  disease  ;  hence 
the  precaution  under  consideration  is  most  desirable,  if  only  on  the  score  of 
dampness.  But  there  are  other  reasons  which  render  it  most  essential. 
Ground  air  itself,  even  if  not  laden  with  watery  vapour,  may  contain  material 
chat  it  is  most  important  to  keep  out  of  the  dwelling,  such  as  carbon  dioxide 
or  it  may  be  poisoned  by  the  soakage  from  a  neighbouring  leaky  drain  or 
sewer,  or  from  an  ashpit  or  a  cesspool.  Even  if  the  street  in  fi-ont  is  not 
flagged  and  paved,  and  the  yard  behind  is  not  flagged  or  asphalted  as  it 
ought  to  be,  the  ground  surface  outside  the  house  is  quite  impervious 
during  a  hard  frost,  and  the  chimneys  and  fires  in  the  dwelling  exercise  to 
a  certain  extent  a  process  of  suction  on  the  ground  immediately  beneath  the 
dwelling,  and  a  quantity  of  ground  air  with  all  its  impurities  may  easily 
be  drawn  into  it.  Nor  is  this  by  any  means  a  mere  theory,  since  instances 
are  on  record  of  ordinary  coal  gas  having  been  thus  drawn  a  considerable 
distance  beneath  the  frozen  surface  of  the  ground,  from  a  leak  in  the  gas 
main  under  a  road  to  the  interior  of  a  neighbouring  dwelling-house.  It 
'   Tenth  Report  of  the  ITedical  Officer  of  the  Privy  Council,  18G7. 


TEE  DWELLING  G61 

is,  therefore,  most  desirable  that  the  surface  of  the  ground  under  every 
■dweUing  should  be  covered  with  a  layer  of  good  cement  concrete,  4  to 
6  inches  thick,  and  floated  over  to  a  smooth  top  surface  with  fine  sand  and 
cement  so  as  to  form  a  close  and  impermeable  floor.  This  concrete  may 
serve  in  many  instances  as  the  floor  itself,  and  thus  save  the  cost  of  any 
other  flooring.  Such  concrete  floor  would  generally  suffice  in  passages, 
halls,  staircases,  sculleries,  washhouses,  pantries,  and  perhaps  in  kitchens 
and  other  offices.  Moreover,  where  a  boarded  floor  is  used,  a  space  of  at 
least  9  inches  has  to  be  left  for  ventilation  and  as  a  precaution  against 
dry  rot  in  the  floor  timbers,  between  the  underside  of  the  floor-joists  and  the 
ground-surface,  whereas  if  the  latter  be  covered  with  such  a  layer  of  concrete 
as  is  above  described,  the  distance  between  its  surface  and  the  underside  of 
the  floor-joists  may,  without  impropriety,  be  reduced  to,  say,  3  inches, 
thus  effecting  a  saving  of  two  courses  of  bricks  (6  inches)  in  the  height  of 
all  the  walls  of  the  building — an  item  which  would  go  some  way  towards 
meeting  the  cost  of  the  concrete. 

The  second  {b)  of  the  indispensable  conditions  above  referred  to  con- 
cerns the  external  walls  of  the  dwelling,  and  the  character  and  construc- 
tion of  these  will  depend  to  a  certain  extent  upon  the  aspect  and  situation 
of  the  building.  Ordinarily  a  brick  wall  only  9  inches  thick  is  not  suf- 
ficient to  keep  out  the  weather,  especially  if  in  anything  like  an  exposed 
position.  The  bricks  are  of  a  porous  nature,  and  driving  rain  will  be 
forced  through  them,  and  show  itself  in  the  shape  of  moisture  and  damp- 
ness on  the  inside.  A  common  stock  brick  will  absorb  as  much  as  one 
pound  of  water,  and  therefore  it  will  be  readily  understood  that  rain 
may  easily  be  driven  through  a  wall  where  the  bricks  known  as  '  headers  ' 
extend  through  the  entire  thickness  of  the  wall.  Indeed,  air  is  constantly 
pressed  through  such  bricks,  and  though  this  may  be  said  to  assist  ventila- 
tion, it  at  the  same  time  tends  to  lower  the  temperature  of  the  interior  of 
the  house.  The  facility  with  which  air  may  be  pressed  through  certain 
kinds  of  bricks  is  shown  by  the  common  experiment  of  coating  the  four  sides 
of  a  porous  brick  with  wax  and  fixing  a  glass  funnel  on  to  each  end  of  the 
brick,  when  sufficient  air  may  be  blown  from  the  mouth  applied  to  the  tube  of 
one  of  the  funnels  so  as  to  obviously  influence  the  flame  of  a  candle  held  near 
the  tube  of  the  other  funnel.  It  is  desirable  in  all  dwellings  that  the  external 
walls  should,  if  of  brickwork,  be  at  least  a  brick  and  a  half — i.e.  14  inches — 
thick,  so  that  there  may  be  a  vertical  layer  of  mortar,  in  addition  to  the 
bricks,  in  the  structure  of  the  wall  itself.  In  the  case  of  stone  walls  and 
walls  in  which  there  is  an  exceptional  quantity  of  mortar,  as  in  rubble  work, 
'flint  work,  and  such  like,  it  is  desirable  to  increase  the  thickness.  In  ex- 
posed situations  it  is  common  to  construct  the  external  walls  of  buildings 
with  a  cavity  2  to  3  inches  wide  between  the  external  and  internal  faces  of 
the  wall,  and  to  join  the  tAvo  portions  of  such  wall  together  by  means  of 
bonding  ties  of  some  non-absorbent  material  placed  at  suitabis  distances 
apart.  Sometimes  these  bonding  ties  are  made  of  iron,  sometimes  of  glazed 
stoneware,  and  such  walls,  if  properly  constructed,  are  generally  sound 
and  sufficiently  stable  for  all  practical  purposes,  while  they  greatly  promote 
the  comfort  and  dryness  of  the  house  itself.  Other  means  of  securing  the 
same  condition  of  dryness  have  been  contrived  with  more  or  less  success, 
such  as  a  vertical  damp-proof  course  of  slates,  or  of  asphalte  or  other  bi- 
tuminous substance.  Compo  or  tiles  or  slates  are  sometimes  used  on  the 
outer  face  of  the  wall  for  the  same  purpose. 

The  third  (c)  condition  above  mentioned  is  intended  to  prevent  the 
passage   of  moisture   vertically  in  the  walls  of  the   dwelling;    hence   the 


6G2  HYGIENE 

damp-proof  course  must  be  laid  throughout  the  entire  thiclaiess  of  every 
wall  and  at  a  level  some  2  or  3  inches  at  the  least  above  that  of  any- 
ground  adjoining  the  wall.  It  must  also  be  below  the  level  of  any  timber 
or  woodwork  in  or  upon  the  wall,  as  such  timber  or  woodwork  obviously 
needs  the  most  complete  protection  from  damp.  The  provision  of  an  eflicient 
damp-proof  course  in  the  external  walls  of  a  building  may  necessitate  the 
formation  of  a  sunk  area  against  the  wall  in  order  that  the  earth  may  be 
kept  at  a  proper  distance  from  that  part  of  the  wall  which,  being  below 
the  general  level  of  the  ground  outside,  is  above  the  level  of  the  damp- 
proof  course.  •  This  is  essential  if  the  dryness  of  the  wall  is  to  be  preserved.. 
Modifications  of  this  kind  of  construction  have  sometimes  been  adopted  by 
which  the  outside  of  that  part  of  the  wall  which  is  above  the  level  of  the 
damp-proof  course  and  beloAV  that  of  the  adjacent  ground  has  been  covered 
with  asphalte  or  other  impervious  material,  or  that  part  of  the  wall  has  been 
constructed  with  a  cavity  and  a  second  damp-proof  course  at  the  level  of  the 
top  of  the  caAdty  ;  but  these  are  contrivances  more  adapted  to  meet  the  re- 
quirements of  certain  exceptional  circumstances,  and  need  not  here  be  referred 
to  in  further  detail.  A  damp-proof  course  is  often  requisite  in  the  case  of 
chimney  stacks  and  parapets  in  order  to  prevent  damp  from  driving  rain 
soaking  downwards  from  the  exposed  upper  portions  of  walls  of  buildings. 

The  fourth  point  {d)  above  referred  to  is  the  construction  of  the  roof  of 
the  dwelling  of  such  material  and  in  such  manner  that  it  will  serve  its  pm'pose 
of  efficiently  protecting  the  interior  of  the  dwelling  from  the  weather — wet,, 
heat,  and  cold.  Eoofs  are  covered  most  frequently  with  slates  or  tiles,  but 
sheet  lead  and  zinc  are  occasionally  used  for  the  purpose,  and  almost  invari- 
ably for  gutters  and  valleys,  cast  iron  being  most  commonly  used  for  eaves^ 
guttering.  Thatch,  though  affording  perhaps  the  greatest  opportunity  for 
IDicturesqueness,  is  now  rarely  used  for  new  dwellings,  as  it  is  less  durable 
than  the  other  materials,  and  is  regarded  as  a  possible  source  of  danger  from 
fire.  It  is,  moreover,  not  free  from  objection  on  sanitary  grounds,  since  it  is 
entirely  vegetable  in  its  nature,  and  therefore  undergoes  comparatively  rapid 
decomposition,  which  is  encouraged  by  the  changes  of  weather  to  which  it  is 
exposed.  It  likewise  affords  harbour  for  insects  and  vermin,  and  has  been 
suspected  of  retainmg  the  infection  of  scarlet  fever  after  that  illness  had  been 
under  treatment  in  a  cottage  with  such  a  roof.^  Slates,  if  properly  laid  and 
with  a  good  '  lap,'  ^  which  ought  not  to  be  less  than  three  inches,  may  perhaps 
be  regarded  as  affording  the  best  ordinary  roof-covering  in  our  climate,  but 
they  ought  invariably  to  be  laid  on  boarding  and  felt,  and  not  merely  on 
laths  as  is  too  frequently  the  case  ;  otherwise  they  allow  the  interior  of  the 
house  to  be  unduly  affected  by  external  temperature.  In  this  respect  tiles 
have  the  advantage,  as  they  afford  a  better  protection  from  heat  and  cold. 
A  tile  roof  has  to  be  constructed  with  a  steeper  pitch  than  a  slate  roof,  as 
the  latter  material  affords  greater  facility  for  rain  water  and  snow  to  run  off 
than  a  tile-covered  roof.  It  is,  of  course,  necessary  to  provide  suitable  gutter- 
ing along  the  eaves  and  elsewhere,  to  collect  the  water  from  the  roof  before 
conveying  it  away  down  the  rain-water  pipes.  And,  as  regards  these  latter, 
it  is  desirable  to  fix  them  at  a  short  distance  from  the  walls  of  the  building 
in  order  to  protect  the  walls  from  damp  in  the  event  of  a  down  pipe  getting 
stopped  up.  Cast-iron  rain-water  pipes  are  often  made  with  a  special  fas- 
tening that  keeps  the  pipe  itself  an  inch  or  two  away  from  the  face  of 
the  wall. 

'  Our  Homes,  p.  8.     Loudon  :  Cassell  &  Co.,  1883. 

2  The  '  lap '  in  slating  is  the  distance  that  each  row  of  slates  overlaps  the  head,  or 
upper  edge,  of  the  second  row  of  slates  below  it. 


THE  DWELLING  GG3 

The  fifth  point  (e)  referred  to  concerns  the  light  and  ventilation  of  the 
dwelling,  and  although  the  latter  forms  the  subject  of  a  special  article  else- 
where, it  may  nevertheless  be  useful  to  draw  attention  to  certain  features  that 
are  indispensable  to  the  dwelling  under  this  head.  First  there  is  the  necessity 
for  providing  adequate  open  space,  not  only  at  the  rear  of  every  dwelling,  but 
also  in  front  thereof,  and  the  importance  attaching  to  this  provision  is  shown 
by  the  stringency  with  which  regulations  for  securing  the  requisite  minimum 
amount  of  space  are  laid  down  in  the  Model  Bye-laws,  already  referred  to.  It 
is  there  prescribed  (clauses  63  and  54)  that  a  clear  distance  of  open  space, 
at  least  twenty-four  feet  across,  measured  to  the  opposite  side  of  the  street, 
if  necessary,  is  to  be  provided  in  front  of  every  new  dwelling-house,  and  also 
that  an  open  space  belonging  exclusively  to  it,  extending  laterally  throughout 
the  entire  width  of  the  building,  is  to  be  provided  at  the  rear,  measuring  from 
a  minimum  of  ten  feet  up  to  twenty-five  feet  across  such  space,  according  to 
the  height  of  the  building,  of  every  new  dwelling.  It  is  further  prescribed 
(clause  No.  55)  that  adequate  windows  are  to  be  provided  in  each  storey  of 
the  building  in  the  walls  which  abut  upon  the  open  space  so  required  to  be 
provided ;  and  likewise  (clause  No.  57)  that  every  room  intended  for  the 
purpose  of  habitation  shall  have  at  least  one  window,  the  size  of  which  is  to 
bear  a  proportion  of  one-tenth  of  the  floor  area  of  the  room,  that  such  window 
is  to  be  made  to  open  to  at  least  half  its  size,  and  so  that  the  opening  may 
extend  to  the  top  of  the  window.  These  regulations  thus  have  the  beneficial 
effect  of  practically  prohibiting  the  use  of  skylights  in  substitution  of  proper 
vertical  windows,  for  the  purposes  of  lighting  and  ventilating  every  room  in  a 
dwelling.  So  also  with  regard  to  the  ventilation  of  a  water-closet  or  earth- 
closet  in  a  dwelling  house ;  not  only  ought  it  to  be  furnished  with  at  least 
one  window  of  a  minimum  superficial  area  of  about  two  square  feet,  opening 
directly  into  the  external  air,  but  it  should  have,  in  addition,  a  second  opening 
of  some  sort,  such  as  2-inch  Tobin  tube  or  some  kind  of  ventilating  air 
brick,  in  order  to  promote  the  circulation  of  air  through  the  closet  indepen- 
dently of  the  air  of  the  house  itself.  These  requirements,  which,  where 
carried  out,  greatly  tend  to  keep  the  air  of  the  closet  piwe  by  the  rapid  removal 
of  offensive  odour,  are  specially  prescribed  in  the  Model  Bye-laws  (clause 
No.  68). 

The  details  of  the  sixth  point  (/),  relating  to  the  removal  of  the  liquid  and 
solid  refuse  from  the  dwelling,  are  likewise  dealt  with  elsewhere,  but  it  is 
necessary  here  to  refer  to  the  arrangements  that  are  requisite  for  receiving 
the  filth  and  refuse  before  they  pass  into  the  channels  of  removal.  These 
arrangements  usually  comprise  the  ordinary  water-closet  apparatus,  dry  earth 
closets,  and  privies  of  various  descriptions,  and  slop  sinks,  likewise  ashpits 
and  dustbins.  These  appliances,  in  one  defective  fprm  or  another,  have  been 
the  cause  of  more  injury  to  health  than  perhaps  all  other  causes  together. 
Water-closets,  by  bringing  drains  leading  to  sewers  and  cesspools  directly 
into  the  dwelling,  have  poisoned  the  air  within  ;  and  badly  contrived  privies 
and  ashpits  outside  the  dwelling  have  poisoned  the  air  and  soil  about  the 
exterior  of  the  dwelling,  as  well  as  the  water  used  by  the  inhabitants.  And 
thus  they  have  combined  to  inflict  upon  the  people  those  terrible  'filth 
diseases,'  as  Sir  John  Simon  has  so  aptly  described  them  in  his  official  re- 
ports, ^  as  Medical  Officer  of  the  Privy  Council  and  Local  Government  Board, 
which  have  not  only  carried  off  such  vast  numbers  of  persons,  but  have  from 
time  to  time  attacked  and  prostrated  a  still  greater  number.     Under  these 

1  See  especially  the  report  on  '  Filth-diseases  and  their  Prevention '  in  the  Supple- 
mentary Report  for  the  year  1873.  New  Series  No.  II.  [c— 1066.]  London :  Eyre  & 
Spottiswoode,  1874. 


GGi  HYGIENE 

circumstances  the  question  of  the  precise  kind  of  closet  apparatus  to  be 
adopted,  whetlier  on  tlie  water  principle  or  on  some  of  the  dry  principles,  is 
a  matter  of  much  importance.  The  leading;-  principles  to  be  observed  in  either 
case  are  dealt  with  in  some  detail  in  the  several  clauses  of  the  Model  Bye- 
laws,  already  referred  to  (clauses  Nos.  G7  to  79).  These  clauses  may  be  said 
generally  to  cover  the  whole  subject,  since  they  prescribe  the  arrangements 
to  be  followed  in  the  construction  of  water-closets  and  of  earth-closets  and 
prices,  wdth  either  fixed  or  with  movable  receptacles.  After  setting  forth 
that  every  new  water-closet  or  earth-closet  is  to  be  so  placed  and  constructed 
as  to  ensure  its  ethcient  ventilation,  the  bye-laws  require  every  new  water- 
closet  to  have  its  separate  cistern  or  flushing-box  furnished  with  means  for 
efiectually  flushing  and  cleansing  the  basin  of  the  closet,  and  for  removmg 
the  excreta  therefrom.  This  requirement  practically  prohibits  the  use  of 
closets  in  which  the  objectional  plan  of  hand  flushing — i.e.  the  occasional 
emptying  of  a  pail  of  water  into  the  basin,  is  relied  upon.  The  necessity, 
for  sanitary  reasons,  for  providing  the  separate  cistern  is  explained  later 
on ; '  but,  as  regards  its  capacity  and  position,  it  may  here  be  pointed 
out  that  in  order  to  make  the  flush  eftectual,  both  as  regards  volume  and 
force,  it  is  requisite  to  fix  the  flushing-cistern  at  least  four  or  five  feet 
above  the  closet-basin,  and  to  provide  a  pipe  from  the  cistern  to  the  basin  of 
at  least  1}  inches  diameter.  The  quantity  of  water  requisite  to  flush  out 
the  basin  and  carry  away  the  excreta  will  depend  to  some  extent  upon  the 
particular  form  of  basin  and  the  kind  of  trap  beneath  it,  but  it  will  rarely  be 
found  that  less  than  two  gallons  will  answer  the  purpose,  and  even  this  will 
often  fail  to  remove  it  further  than  from  the  basin  to  the  trap,  where  the 
solids  will  remain  until  the  next  time  a  flush  is  applied.  For  more  effectually 
flushing  the  trap  and  soil-pipe,  as  well  as  the  basin,  it  would  be  better  to 
use  three  gallons  of  water  at  a  time.  This  quantity,  though  objected  to  by 
many  water  companies,  has  been  advocated  as  necessary  by  many  sanitary 
engineers  and  others  who  have  paid  special  attention  to  the  point,  and  the 
only  alternative  that  can  be  recommended  is  to  apply  a  second  flush  each 
time  the  closet  is  used.  To  this,  however,  a  difficulty  has  been  interposed 
in  the  interests  of  the  water  companies,  by  which,  owing  to  the  small  size  of 
the  pipe  supplying  the  flushing  cistern  "v\ith  water,  the  time  occupied  is  so 
great  that  few  persons  are  willing  to  wait  while  the  flushing  cistern  is 
getting  re-charged,  after  the  first  flush  has  been  applied  to  the  basin.  In  some 
instances  as  much  as  eight  or  ten  minutes  elapse  before  it  is  full,  and  con- 
sequently, as  the  application  of  the  second  flush  recommended  is  rarely 
practicable,  it  is  better  to  insist  upon  the  larger  capacity  of  the  cistern.  But 
if  the  supply-pipe  were  so  enlarged  as  to  fill  the  cistern  in,  say,  two  minutes, 
the  smaller  capacity  might  possibly  be  regarded  as  adequate,  a  second  flush 
being  recommended  on  every  occasion  the  closet  is  used. 

The  Model  Bye-laws  next  require  the  water-closet  to  have  a  basm  of  non- 
absorbent  material,  and  of  such  shape  and  capacity,  &c.,  as  will  contain  a 
sufficient  quantity  of  water,  and  will  allow  the  excreta  to  fall  free  of  the 
sides,  and  directly  into  the  water  in  the  basin.  This  requirement,  which  is 
necessary  in  the  interests  of  cleanliness,  practically  prohibits  the  use  of  the 
long  hopper-shaped  closet-basin  (fig.  108)  so  commonly  met  with  in  cottage 
closets  and  in  servants'  closets,  and  in  which  the  excreta  invariably  hang 
about  the  sides  and  fail  to  be  removed  by  the  sluggish  flow  of  water  in  a 
spiral  course  round  the  basin.  The  ordinary  valve-closet  basin  shown  in 
fig.  109  obviously  conforrus  with  this  re(|uirenaent,  and  is  one  of  the  best 

'  See  p.  CC7. 


THE  DWELLING 


665 


■■(sssaEi 


..f.'j/jjj/jjjj}, 


Fig.  108. 


FxG.  IIL 


Fie.  109. 


Fig.  112. 


Fig.  110. 


Fig.  113. 


G6G  HYGIEXE 

forms  of  closet  apparatus,  especially  when  made  with  a  spout  or  lip  on  the 
edge  of  the  basin  to  serve  as  an  overflow  into  the  safe  below,  instead  of  the 
overflow-pipe  dehverhig  beneath  the  valve  as  shown  in  fig.  110.  Other  forms 
of  closet-basin  complying  with  this  requirement  are  shown  in  the  *  wash- 
out' and  hopper-shaped  basins  in  figs.  Ill  and  112.  The  same  Model 
Bye-lav\^  (clause  69)  next  proceeds  to  prohibit  the  fixing  in  any  new  water- 
closet  of  what  is  known  as  a  'container'  and 'D  trap.'  These  appliances 
were,  for  many  years,  most  common.  They  are  still  often  used  notwith- 
standing their  general  condemnation  by  sanitarians,  and  are  met  with  all 
over  the  kingdom,  as  well  as  in  Continental  towns.  A  section  of  this  kind  of 
apparatus,  with  the  '  container '  and  '  D  trap,'  is  given  in  fig.  113  and  fig.  114, 
showing  as  nearly  as  possible  the  actual  state  of  the  interior  of  the  trap  after 
a  few  months'  use.  The  two  appliances  referred  to  involve  the  retention  of 
excreta  in  them,  often  for  many  hours  together,  with  the  result  that  the  sides 
get  coated  over  with  a  filthy  slime  or  deposit  which  emits  that  offensive  and 
nK)st  unwholesome  odour  invariably  met  with  in  these  closets  when  the 
handle  is  pulled  up  for  the  basin  to  be  emptied.  The  interior  of  these  appli- 
ances not  being  subjected  to  the  full  force  of  the  flush  of  water  in  the  basin, 
the  filth  gets  deposited  over  it  in  the  way  shown,  and  this  process  of  deposit 
is  much  aided  in  the  container  by  the  use  of  iron,  of  which  the  container  is 
usually  made. 

As  regards  the  seventh  point  (g),  the  means  of  storing  and  distributing 
water,  it  is  of  the  utmost  importance  that  the  arrangements  generally  should 

admit  of  an  unstinted  supply  being 
available  to  the  inmates  of  every  dwelling. 
The  amount  per  head  per  diem  that 
is  requisite  in  an  ordinary  dwelling 
depends  necessarily  upon  a  great  variety 
of  circumstances,  and  is  dealt  with  in 
another  part  (see  p.  243). 

Where  the  supply  is  on  the  constant 
system  cisterns  are  still  requisite,  as  the 
supply,  being  through  a  small  tap,  is  not 
always  as  rapid  as  may  be  temporarily 
necessary,  and,  moreover,  when  it  is 
cut  off  for  a  few  hours  during  the  repair 
^^°-  1^^-  of  a  main,  much  inconvenience  might 

arise  if  there  were  no  storage-cistern  of  moderate  capacity ;  but  the  size 
might  be  very  much  smaller  than  where  the  water  is  supplied  on  the  inter- 
mittent system.  On  the  other  hand,  there  is  some  disadvantage  in  the 
cistern  being  of  excessive  size,  as  the  water  in  it  may  in  that  case  not  be 
changed  sufficiently  often,  and  thus  become  affected  by  stagnation. 

For  the  storage  of  the  requisite  quantity  of  water,  tanks  or  cisterns  are 
usually  provided  at  such  height  above  the  ground  as  will  allow  of  the  water 
beinf^  dehvered  by  gravitation  where  it  is  wanted  below  the  level  of  the 
cisterns.  These  cisterns  are  ordinarily  made  either  of  slate,  iron,  lead,  or 
wood  lined  with  lead  or  zinc,  and  are  fitted  with  a  ball-cock  or  valve  to  regu- 
late the  admission  of  water  from  the  main  supply  according  to  the  level  of 
the  surface  of  the  water  in  the  cistern,  and  an  overflow-  or  warning-pipe  to 
indicate  when  the  cistern  is  full,  or  when  the  ball-valve  may  be  out  of  order, 
to  ob^date  the  inconvenience  of  the  cistern  overflowing.  There  are  serious 
objections  to  the  use  of  lead  for  cisterns,  as  certain  water,  especially  rain- 
7/ater  or  soft-water,  will  readily  become  poisoned  by  the  lead  ;  and  this 
objection  also  apphes,  in  a  less  degree,  in  the  case  of  zinc  cisterns.     Iron  is 


THE  DWELLING  CG7 

likewise  not  free  from  objection,  unless  covered  with  some  suitable  protective 
material.  Slate,  especially  if  enamelled,  is  probably  the  best  material  for 
cisterns,  though  there  is  some  difficulty  in  making  the  joints  permanently 
watertight,  and  therefore  such  cisterns  should  always  have  a  proper  safe  or 
tray  beneath  them  to  prevent  leakage  from  soaking  into  the  building  beneath. 
Every  cistern  ought  to  be  so  placed  as  to  be  easily  accessible  for  the  purpose 
of  inspection  and  periodical  cleansing,  which  ought  to  be  done  at  intervals  of 
not  more  than  about  three  months.  In  order  that  this  cleansing  of  the 
cistern  may  be  effectually  done  it  is  necessary  that  there  should  be  ample 
means  for  the  admission  of  light  to  it ;  but  the  water  in  a  cistern  or  tank 
should  not  be  constantly  exposed  to  light,  as  this  would  tend  to  encourage 
algoid  growth  in  the  water.  It  ought  also  to  be  covered  over  in  order  to 
prevent  dust,  leaves,  and  other  substances,  as  well  as  mice,  small  birds  and 
insects,  from  getting  in  ;  and  should  likewise  be  well  ventilated,  and  protected 
from  extremes  of  temperature.  Special  precautions  should  be  taken  if  the 
cistern  is  placed  in  a  position  where  the  water  in  it  may  be  expected  to 
freeze  in  cold  weather,  as  the  expansion  of  the  water  when  frozen  may  lead  to 
the  joints  of  the  cistern  being  damaged  and  result  in  much  inconvenience 
when  a  thaw  sets  in.  Unless  the  cistern  is  protected  in  some  way,  it  should 
be  made  with  sloping  sides,  the  top  being  wider  than  the  bottom  in  order  to 
allow  the  water,  in  the  process  of  freezing,  to  expand  upwards  without  exer- 
cising much  pressure  on  the  sides. 

For  the  purpose  of  facilitating  repairs  to  the  cistern  or  to  the  service- 
pipes  leading  therefrom,  without  arresting  the  distribution  of  water  about 
the  house,  it  is  often  useful  to  arrange  the  cistern  in  two  compartments,  one 
feeding  the  other  and  both  connected  with  the  service-pipes,  but  fitted  with 
stop-cocks  so  that  the  service-pipes  could  draw  their  supply  from  either  of 
the  compartments  while  the  other  was  temporarily  emptied  for  repairs, 
cleansing,  &c.  So  also  the  service-pipes  would,  in  that  case,  be  capable  of 
being  shut  off  from  the  cistern  by  means  of  the  stop-cocks  and  be  emptied 
for  repair  or  for  replacing  a  defective  draw-off  tap,  or  on  the  approach 
of  very  cold  weather,  when  the  water  in  the  pipes  might  be  expected  to 
freeze. 

It  must  always  be  borne  in  mind  that  the  water-supply  to  the  water- 
closets  of  a  house  must  not  be  direct  from  the  main  supply-pipe,  or  from  any 
of  the  storage  cisterns  supplying  water  used  for  dietetic  and  domestic  purposes. 
Numerous  instances  are  recorded  showing  that  outbreaks  of  enteric  or  typhoid 
fever  have  resulted  from  supplying  water  to  water-closets  direct  from  the 
water  main,  instead  of  through  the  intervention  of  a  cistern.  Under  such 
circumstances,  any  intentional  or  unavoidable  intermission  of  the  water- 
service  facilitates  and  ensures  the  forcible  suction  of  foul  air,  and,  at  times,. 
even  other  matters,  into  the  mains  of  the  water-service.  Hence  service- 
cisterns  ought  to  be  provided,  in  order  to  ensure  a  complete  break  between  the 
basin  of  a  water-closet  and  the  water-main ;  and  inasmuch  as,  even  where 
such  a  cistern  is  provided,  there  still  remains  a  tendency  for  the  escape  of 
foul  air  from  the  basin  of  the  closet  up  the  service-pipe  and  through  the  body 
of  water  in  the  cistern  itself,  thus  leading  to  contamination  of  the  water, 
a  special  cistern  is  necessary  exclusively  for  the  water-closet,  and  what  is 
known  as  a  water  waste-preventing  cistern,  similar  in  principle  to  what  is 
commonly  required  by  the  water  companies,  answers  the  purpose  efficiently. 

It  may  be  useful  here  to  refer  briefly  to  certain  objections  to  the  inter- 
mittent system  of  water-supply — objections  which  apply  equally  to  cases  where 
the  so-called  constant  supply  is  in  use,  but,  from  scarcity  of  water  during 
periods  of  drought  or  otherwise,  not  continuously  in  operation.     It  has  on 


CG8  HYGIENE 

several  occasions  happened  that,  under  such  circumstances,  the  suction 
into  the  pipes  has  been  such  that  various  contaminating  matters,  as  foul  air, 
sewage  and  focal  matter,  blood  from  slaughter-houses,  &c.,  have  been  drawn 
into  the  pipes,  and  subsequently  distributed  in  the  water,  with  the  result  that 
fever  was  produced  in  the  neighbourhood. 

For  the  distribution  of  water  about  the  dwelling  lead  pipes  are  usually 
adopted  ;  but  as  certain  waters  act  upon  any  lead  with  which  they  may  come 
in  contact  and  become  poisoned,  it  would  be  better  if  pipes  of  some  other 
material  were  adopted.  But  there  are  so  many  advantages  in  the  use  of  lead 
pipes,  and  the  evil  results,  where  the  water  is  not  allowed  to  remain  long  in 
them,  are  so  rarely  serious,  that  it  is  almost  useless  at  present  to  urge  the 
adoption  of  other  pipes.  Tin  pipes,  or  tin-lined  leaden  pipes,  however,  have 
in  some  instances  been  used  with  much  advantage. 

Turning  now  to  the  consideration  of  the  several  classes  of  dwellings  above 
enumerated,  we  come  Jirst  to  the  class  of  mansions  and  palatial  residences  of 
the  rich,  and  perhaps  there  is  less  to  be  said  about  them  hygienically  than 
about  any  of  the  other  classes,  partly  because  they  are  usually  constructed 
under  the  exceptional  advantages  of  liberal  expenditure  and  good  professional 
advice,  partly  also  because,  as  regards  air-space  both  within  and  ^\-ithout, 
there  is  usually  much  less  necessity  for  stint  than  in  the  case  of  dwellings  of 
the  other  classes,  and  partly  because  they  are  not  always  in  full  occupa- 
tion. There  are,  nevertheless,  some  points  about  even  this  class  of  house, 
both  ancient  and  modern,  that  need  more  attention  than  is  often  bestowed 
upon  them,  and  indeed  instances  are  not  wanting  to  show  that  grave  defects 
have  been  allowed  to  exist  in  some  old  mansions,  or  to  be  created  in  some 
new  ones,  which  have  resulted  in  more  or  less  serious  effect  upon  the  mhabi- 
tants,  sometimes  affecting  the  servants,  sometimes  the  visitors,  and  some- 
times the  members  of  the  family  OAvning  and  occupying  the  mansion. 
These  defects  have  been  apparent  mainly  in  the  matter  of  the  drainage  or 
sewerage  arrangement,  though  the  imperfections  of  water-closets,  and  the 
absence  of  any  sort  of  disconnection  between  the  interior  of  the  house  and 
the  drains,  have  also,  in  many  instances,  come  to  be  Imown  as  the  direct 
cause  of  disease.  There  are,  however,  certain  other  defects  common  in  the 
class  of  house  referred  to  that  may  have  a  considerable  influence  on  the 
health  of  the  inmates.  That  they  are  in  some  instances  unduly  crowded  on 
area,  especially  in  the  case  of  mansions  situated  in  the  metropolis,  can  hardly 
be  denied :  for  in  such  cases  it  is  common  to  find  the  building  covermg  the 
entire  area  of  the  site,  while  one  or  more  small  courts  or  wells,  intended  for 
■  light  and  air,  descend  in  the  middle  from  the  top  as  far  as  the  roof  of  the 
ground  storey,  where  skylights  alone  afford  to  the  rooms  and  offices  below 
them  such  poor  supply  of  light  and  ventilation  as  may  chance  to  be  avail- 
able, and  windows  around  this  well  of  stagnant  air  are  supposed  to  suffice 
for  a  number  of  rooms,  &c.,  abutting  upon  it.  Inasmuch,  however,  as  these 
houses  are  commonly  more  or  less  empty  during  the  greater  part  of  every 
year,  and  are  only  fully  occupied  during  a  short  season  of  annual  festivity, 
this  defect,  which  in  the  case  of  an  institution  always  occupied  to  its  full 
capacity  would  be  most  serious,  can  hardly  be  said  to  apply. 

There  is  a  curious  instance  of  a  design  for  a  mansion  on  what  may  be 
called  the  pavilion  system.  A  celebrated  architect,  John  Thorpe,  who  lived 
in  the  time  of  Queen  Elizabeth,  and  who  designed  and  carried  out  many  man- 
sions and  palaces  at  that  period,  has  left  an  interesting  design  for  a  house  for 
himself,  but  which  was  not  erected.  This  design  is  preserved  in  Sir  John 
Soane's  museum  in  Lincoln's  Inn  Fields,  and  is  in  the  form  of  his  own  initial 
letters  I  and  T,  the  portion  of  the  building  comprised  in  the  letter  I  containing 


THE  V  WELLING 


GG9 


Fig.  115. — Plan  of  John  Thorpe's  house. 


the  kitchen  offices  and  servants'  quarters,  and  that  comprised  in  the  letter  T 
containing  the  principal  rooms  and  residential  apartments  of  the  house,  the 
two  letters  being  joined 
together  by  means  of  a 
one- storey  connecting  cor- 
ridor. The  author  of  the 
design  facetiously  explains 
it  in  the  following  doggerel 
rhyme : — 

Thes  2  letters  I  and  T 

ioyned  together  as  you  see 
Is  ment  for  a  dwelling  house 
for  mee 

John  Thorpe. 

Although  Thorpe's  prime 
object  was  no  doubt  to 
arrange    his  plan  in  the 

form  of  his  own  initial  letters,  there  was  considerable  advantage  in  the 
effectual  separation  of  the  culinary  department  from  the  main  residential  por- 
tion of  the  house  ;  but,  even  if  this  idea  formed  a  basis  for  the  arrangement,  it 
was  only  partially  adopted,  since  the  upper  storeys  of  the  portion  compris- 
ing the  letter  I  appear  to  have  been  intended  for  residential  apartments,  pro- 
bably for  the  servants. 

One  of  the  chief  sanitary  defects  in  old  mansions  is  the  method  of  dis- 
posal of  the  sewage.  In  the  country  this  has  generally  been  conveyed  first 
into  subsiding  tanks  or  cesspools  and  then  into  some  lake  or  ornamental 
piece  of  water,  or  into  some  stream  or  river.  In  towns  and  in  the  metro- 
polis this  use  of  cesspools  has  been  very  largely  resorted  to  before  the  Liquid 
has  been  allowed  to  flow  into  the  sewers  or  directly  into  the  river.  These 
conditions  still  exist  in  the  case  of  very  many  large  mansions,  notwith- 
standing that  the  arrangements  described  are  directly  prohibited  by  modern 
Acts  of  Parliament,  and  that  the  owners  of  such  mansions  are  frequently 
themselves  members  of  one  or  other  of  the  Houses  of  Legislature,  or  are 
otherwise  concerned  in  the  making  and  administration  of  the  laws  of  the 
land.  Here  and  there,  where  grave  insanitary  conditions  have  been  dis- 
covered or  where  illness  or  perhaps  death  has  resulted  from  these  conditions, 
remedies  or  improvements  have  been  effected ;  but  these  would  seem  to  be 
but  comparatively  isolated  instances.  It  was  only  after  severe  illness  in 
the  house  that  the  site  upon  which  Marlborough  House  stands  was  dis- 
covered to  be  dotted  about  with  old  cesspools  and  traversed  by  old  drains,  the 
very  existence  of  which  was  unknown,  but  which  served  to  saturate  the 
ground  beneath  the  house  with  filth.  This  discovery,  in  1877,  naturally 
led  to  very  extensive  and  costly  works,  comprising  the  removal  of  all  the  old 
cesspools  and  drains  as  well  as  the  contaminated  earth,  the  construction  of  a 
new  system  of  drains  external  to  the  house,  and  the  covering  of  the  ground- 
surface  within  the  house  with  a  layer  of  Portland  cement  concrete.'  Again, 
in  this  class  of  house  grave  results  have  repeatedly  arisen  from  the  position 
and  construction  of  the  water-closet  practically  necessitating  the  drains  being 
brought  close  up  to,  or  even  within,  the  bedrooms  and  private  apartments  of 
the  household,  the  closet  itself  having  no  independent  ventilation,  and  con- 
stantly delivering  subtle  poisons  into  the  inhabited  rooms.  So,  too,  the 
domestic  offices,  larders,  pantries,  and  dairies  have  been  found  to  be  placed 


'  The  Builder,  1877,  p.  1251. 


G70  HYGIENE 

■where  the  servants,  as  well  as  the  food,  have  been  exposed  to  the  effects,  not 
merely  of  bad  drainage  arrangements,  but  of  ah'  that  has  been  vitiated  in 
vai'ious  ways,  perhaps  most  often  by  damp  and  other  exhalations  from  the 
ground.  While  in  many  old  houses  of  this  class  the  defective  and  unwhole- 
some arrangements  above  described  are  allowed  to  remain  undisturbed, 
on  account  of  the  wholesale  character  of  the  alterations  that  would  be 
necessary  were  they  to  be  remedied,  it  must  be  admitted  that,  in  those 
mansions  of  quite  recent  construction,  the  more  obvious  defects,  at  any  rate, 
have  generally  been  carefully  avoided. 

As  regardsthe  second  class  of  dwellings  referred  to  at  page  058,  the  sub- 
urban and  country  house  of  the  ordinary  professional  man  of  business  and 
wealthy  tradesman,  the  parsonage  or  vicarage,  and  the  better  kind  of  farm- 
house— these  are  far  more  numerous  than  the  dwellings  comprised  in  the 
first  class,  and  in  many  respects  they  may  be  said  to  contain  the  same 
general  characteristics  as  the  latter,  but  in  a  somewhat  modified  form.  In 
a  vast  number  of  instances  the  same  kind  of  defects  may  be  found  in  this 
class  of  house  as  in  the  first  class,  but  in  the  main  the  houses  in  the  second 
class  are,  with  the  exceptions  referred  to,  fairly  well  adapted  to  their  purposes. 
There  are,  however,  some  features  about  them  that  mi;st  be  briefly  referred 
to,  such  as  the  circumstance  that  they  are  usually  more  permanently  occu- 
pied than  the  palatial  mansions,  and  accordingly  any  defect  is  more 
likely  to  produce  more  intense  effect  than  where  the  dwelling  is  allowed  to 
remain  empty  for  a  certain  period  every  year.  Then,  again,  in  this  land 
of  dwelling  the  inferior  apartments,  such  as  the  bedrooms  set  apart  for 
servants,  are  often  so  placed  and  constructed  as  to  be  indifferently  warmed 
and  ventilated,  or  so  as  to  be  readily  affected  by  external  temperature, 
or  they  are  placed  in  undue  proximity  to  the  domestic  offices,  stables, 
&c.,  and  so  that  the  smell  from  these  places  is  never  absent  from  the 
apartments. 

In  the  case  of  vicarages  and  rectories,  the  fact  of  their  being  periodically 
overhauled  by  officers  of  the  Ecclesiastical  Commissioners  or  the  Diocesan 
Surveyor,  whenever  there  is  a  change  of  the  incumbency,  leads  to  their 
being  generally  kept  pretty  well  up  to  date  in  regard  to  most  of  the  ordinary 
hygienic  requirements,  while,  as  regards  new  parsonages,  they  have  to  be 
erected  in  conformity  with  the  somewhat  stringent  requirements  of  the 
Ecclesiastical  Commissioners,  and  although  these  may  not  always  be  as 
complete  and  effectual  as  the  hygienist  w^ould  desire,  they  are,  nevertheless, 
very  useful  in  securing  substantial  construction  on  sound  general  principles. 

The  third  class  of  dwellings  to  which  reference  has  been  made  involves 
certain  difficulties  of  arrangement  which  are  seldom  met  with  in  connection 
with  the  two  precedmg  classes  of  dwellings.  With  this  class,  which  is  more 
urban  in  character  than  the  country-house  already  referred  to,  commences 
the  embryo  of  that  important  question  of  adequacy  of  open  space  about 
the  dwelling,  both  to  the  front  and  to  the  rear,  in  order  to  ensure  facilities 
for  free  circulation  of  air  about  the  house  and  opportunity  of  ventilating  the 
interior.  Owing  to  the  greater  value  of  land  in  the  urban  district  than  in  the 
open  country,  this  difficulty  increases  in  proportion  as  the  dwelling  is  nearer 
to  the  centre  of  the  urban  district,  where,  owing  to  the  exigencies  of  popula- 
tion, trade,  and  business,  the  houses  are  necessarily  packed  somewhat  closely 
together  and  built  of  great  height.  Lideed,  every  new  building  that  is 
erected  on  the  site  of  an  old  one  is  often  made  fully  twice  as  high  as  its  pre- 
decessor. To  such  an  extent  is  this  the  case  in  some  localities  that  dwellings 
have  to  be  piled  one  on  the  top  of  another,  many  storeys  in  height,  under  the 
same  roof,  under  the  modern  denomination  of  '  flats.'     Accordingly,  under 


THE  DWELLING  671 

this  head  are  comprised  the  ordinary  detached  and  semi-detached  house  of 
moderate  size,  and  the  terrace-house,  or  house  in  a  row  of  attached  houses  of 
indefinite  length,  of  size  and  value  varying  from  the  ten-  or  twelve-roomed 
house,  of  a  rental  of  some  sixty  or  seventy  pounds  a  year,  to  the  town-house 
of  two  or  three  times  that  size  and  eight  or  ten  times  the  rental  value, 
situated  in  the  best  residential  streets  at  the  West -end  of  the  metropolis  and 
of  the  provincial  towns.  The  system  of  flats,  which  is  a  modern  innovation 
from  the  Continent,  possesses  many  advantages,  when  well  carried  out,  over 
certain  classes  of  houses  for  the  middle  classes  in  the  ordinary  streets  of 
London  and  other  towns.  It  may  he  described  as  that  of  laying  the  ordinary 
tall  house  down  horizontally.  Such  a  house  obviously  occupies  a  larger  area 
than  the  same  accommodation  arranged  vertically  in  the  one  house  of  some  six 
or  seven  storeys  ;  but,  on  the  other  hand,  the  entire  block  of  flats  may  be 
several  storeys  high,  and  at  least  as  many  sets  of  flats  or  dwellings  can  be 
arranged  on  the  same  area.  It  would  also  be  possible  to  arrange  the  several 
dwellings  in  various  sizes  to  suit  the  requirements  of  different  tenants.  The 
advantage  gained  by  throwing  the  several  small  backyards  separated  by  the 
party  fence  walls  that  would  have  to  be  provided  behind  the  row  of  tall  narrow 
houses,  into  one  undivided  yard  of  considerable  length  would  alone  be  con- 
siderable, while  if,  in  the  case  of  a  site  lying  between  two  streets,  the  court- 
yards were  arranged  to  communicate  with  the  streets  by  means  of  clear 
openings  or  large  archways,  the  advantages  as  regards  circulation  of  air 
would  be  greatly  increased.  As  an  indication  of  this  latter  arrangement  an 
excellent  plan,^  designed  by  Mr.  "William  H.  White,  F.E.I.B.A.,  was  laid 
before  the  Eoyal  Institute  of  British  Architects  in  1877,  showing  how  the 
block  of  twenty-eight  London  shops  and  dwellings  lying  between Eegent  Street 
and  Warwick  Street  on  their  west  and  east,  and  Beak  Street  and  Eegent  Place 
on  their  north  and  south,  have  from  time  to  time  been  altered  and  inter- 
mingled, until  they  have  become  only  twenty  in  number,  and  practically  the 
entire  area  has  been  gradually  covered  with  building,  for  only  four  or  five 
very  small  well-holes  remain  open  for  light  and  air,  the  frontages  of  the 
buildings  extending  continuously  all  round  the  site.  By  the  rearrangement 
and  reconstruction  of  the  buildings  on  this  'island,'  Mr.  White  shows  that 
as  many  as  twenty-one  shops  and  nineteen  good  and  roomy  houses  might  be 
constructed  upon  it,  while  the  courtyards  would  be  such  as  would  ensure  free 
circulation  of  air  and  ample  light.  One  important  feature  that  appears  re- 
quisite to  bear  in  mind  in  the  case  of  a  block  of  dwellings  arranged  as  '  flats  ' 
is  the  advisability,  in  the  interests  of  health,  of  so  arranging  the  common 
staircase  or  staircases  that,  if  they  are  not  open  to  the  external  air,  they  shall 
at  least  be  capable  of  good  through-ventilation  by  opposite  external  windows. 
This  would  be  of  special  advantage  as  tending  to  prevent  the  spread  of 
infection  in  the  event  of  any  dangerous  infectious  disease  occurring  in  any 
dwelling  in  the  block. 

The  kind  of  dwelling  comprised  within  the  fourth  class  above  alluded  to 
— namely  the  dwelling  in  connection  with  the  place  of  business,  the  hotel, 
inn,  &c. — is  very  numerous,  and  includes  not  only  the  ordinary  ten-  or  twelve- 
roomed  house  with  a  shop  in  the  ground  storey,  but  the  large  drapery  esta- 
blishments and  other  commercial  houses  where  the  upper  part  is  devoted  to 
apartments  for  the  numerous  employes  of  both  sexes  engaged  in  the  service 
of  the  establishment,  and  who  in  some  instances  are  many  hundreds  in 
number.  In  this  sort  of  dwelling  the  question  of  open  air  space  about  the 
house  is  often  involved  in  much  difficulty,  for  the  chief  value  of  the  premises 

'  Illustrated  and  described  in  tlie  Transactions  of  the  B.I.B.A.,  and  also  in  Our 
Homes.    London  :  Cassell  &  Co.,  1883. 


672  HYGIENE 

lies  in  their  capacity  for  the  purposes  of  business,  and  accordingly  the  super- 
ficial area  available  for  shop  purposes  in  the  ground  storey — or  more  particu- 
larly at  the  street  level— with  such  additional  space  for  showrooms,  ware- 
rooms,  and  the  Hke,  in  immediate  connection  with  the  shop,  constitutes  the 
chief  element  in  the  value  of  the  premises  from  the  purely  business  point  of 
view.  Hence  everythingis  sacrificed  to  increasing  the  area  available  for  business 
requirements,  and  unless  some  control  be  exercised  over  the  arrangements, 
the  health  conditions  of  the  premises  are  undoubtedly  prejudiced.  Thus  in 
all  such  cases  the  first  effort  is  to  secure  the  largest  area  possible  for  the 
shop,  and  accordingly  this  is  extended  over  the  entire  area  of  the  site  from 
front  to  rear  boundary,  so  as  to  preclude  the  possibihty  of  forming  any  sort 
of  yard  at  the  ground  level  where  the  necessary  ashpit  or  dustbin  may  be  put, 
and  so  as  to  exclude  all  means  of  lighting  and  ventilating  the  basement  storey, 
except  from  a  sort  of  shallow  area  beneath  the  shop  window  in  front.  Some- 
times palhatives  for  these  defects  are  provided  in  the  shape  of  reflectors  for 
light  and  air-shafts  for  ventilation  ;  but  these,  as  a  general  rule,  hopelessly 
fail  to  effect  their  purpose  to  the  necessary  extent,  since  gas  or  other  artificial 
light  has  often  to  be  constantly  used,  and  the  ventilation  of  the  basement  is 
left  to  take  care  of  itself;  and  this  notwithstanding  that  dozens  of  young 
men  and  women  may  be  employed  in  this  storey  during  many  consecutive 
hours  from  morning  till  evening.  Nor  is  this  all :  it  is  not  uncommon  to 
find  in  this  artificially  lighted  and  imperfectly  ventilated  basement  the  closet, 
urinal,  and  lavatory  accommodation  for  certain  of  the  employes,  which  is 
merely  screened  off,  so  to  speak,  from  the  main  apartment,  and  is  utterly 
incapable  of  being  maintained  in  a  proper  and  wholesome  condition,  however 
well  it  may  be  kept  by  those  servants  immediately  responsible  for  its  clean- 
liness. 

In  the  shop  itself  the  ventilation  mainly  relied  upon  is  generally  the  front 
doorway,  which  is  kept  open  for  customers  as  much  as  possible,  and  some 
skylights  having  a  small  portion  to  open,  over  the  rear  portion  of  the  shop  ; 
but  this  is  rarely  sufficient  to  keep  the  air  within  it  even  moderately  pure. 
The  quantity  of  gas  frequently  consumed  in  large  shops,  the  ascent  of  ^'itiated 
air  by  the  stairs  from  the  wareroom  or  offices  in  the  basement,  the  exhala- 
tions from  the  large  numbers  of  employes  and  from  customers,  as  well  as  the 
emanations  from  the  clothes  of  the  latter,  particularly  in  wet  or  warm  weather, 
and  the  dust,  particles  of  fibre,  and  smell  from  the  stock  and  goods  in  the 
shop,  all  combine  to  render  the  atmosphere  vmwholesome.  Add  to  this  the 
conditions  of  fatigue,  posture,  long  hours,  &c.,  under  which  the  employes  have 
to  perform  their  vrork,  and  it  will  be  seen  that  the  conditions  are  often  far 
from  satisfactory.  It  further  frequently  happens  that  the  sleeping  apartments 
of  the  employes  are  so  placed  in  the  house  above  the  shop  and  showrooms 
that  the  products  of  combustion  of  gas  and  the  other  deleterious  conditions 
of  the  air  in  the  shop  are  easily  conveyed  by  ill- ventilated  staircase  and  passages 
to  the  upper  storeys,  and  thus  contaminate  the  air  in  which  the  employes 
pass  the  night.  There  are  many  establishments  where  these  defects,  if  they 
exist  at  all,  have  been  reduced  to  a  minimum — where  the  whole  condition, 
bygienically,  mentally,  morally,  and  physically,  of  the  employes  is  the  constant 
care  of  the  principal  and  his  higher  staff' — but  there  are  also  numerous  others 
where  a  very  cursory  inspection  will  demonstrate  the  necessity  for  improve- 
ment, while  in  the  case  of  the  erection  anew  of  such  establishments  it  ought 
not  to  be  difficult  to  so  contrive  them  as  to  obviate  most  of  the  defects  referred 
to.  There  is,  however,  one  further  point  affecting  the  hygienic  conditions  of 
such  establishments  to  which  attention  should  be  directed,  and  this  is  the 
amount  of  closet  accommodation  that  is  requisite  for  the  employes  of  each 


THE  DWELLING  G73 

sex.  In  some  instances  it  has  been  found  wholly  inadequate  to  the  numbers 
employed,  the  number  of  the  latter  having  increased  with  the  extension  of 
business  ;  in  other  instances  it  has  been  found  to  be  so  arranged  as  to  be  not 
readily  available,  or  to  be  so  improperly  separated,  that  for  one  sex  from  that 
for  the  other  sex,  as  to  tend  to  prevent  that  regular  use  of  these  conveniences 
which  is  essential  to  health. 

The  hotel,  inn,  public-house,  restaurant,  and  other  dwellings  of  that  cha- 
racter, undoubtedly  demand  more  serious  attention  from  a  hygienic  point 
of  view  than  they  have  perhaps  hitherto  generally  received.  In  the 
modern  palatial  hotel  much  has  been  done  to  avoid  many  of  the  defects 
that  are  common  in  the  old-fashioned  hotels,  though  even  here  defects  of 
want  of  light  and  air  consequent  upon  the  effort  to  crowd  too  much  building 
upon  area  are  of  too  frequent  occurrence.  But  all  who  have  occasion  to  stay  at 
the  old-fashioned  family  and  commercial  hotel  or  inn,  especially  in  the  older 
cathedral  towns  and  in  most  market  towns,  will  be  intimately  acquainted 
with  the  close,  fusty  atmosphere  within  its  walls.  At  night,  on  retiring 
to  his  bedroom,  the  visitor  will  find  it  impossible  to  escape  the  smell  of  cook- 
ing and  the  odours  from  the  bar-parlour,  together  with  the  products  of  com- 
bustion from  the  numerous  gaslights  and  lamps.  On  opening  his  bedroom 
•door  in  the  morning  to  take  in  his  boots  and  hot  water,  he  will  encounter 
the  strong  smell  of  fried  bacon,  fish,  coffee,  and  other  preparations  for 
breakfast ;  and  he  will  be  fortunate  if,  during  or  after  his  stay  in  the  hotel, 
he  do  not  suffer  from  the  effects  of  defective  or  obsolete  forms  of  water-closet 
arrangement  and  fittings,  the  ill-contrived  chamber-maid's  slop-sink,  and 
the  badly  arranged  and  rarely  cleaned  cistern  in  near  proximity  to  his 
apartment.  To  the  casual  visitor  these  objectionable  conditions  may  perhaps 
be  of  comparatively  small  moment,  but  to  the  numerous  servants  who  pass 
their  whole  time  on  the  premises,  night  after  night  and  day  after  day,  the 
■effect  is  probably  more  serious,  and  goes  far  to  account  for  the  pallor  and 
eallowness  of  complexion  so  commonly  met  with  among  this  class  of  servants, 
who,  moreover,  frequently  occupy  only  indifferent  apartments  and  have  very 
poor  accommodation,^  barely  complying  with  rules  that  would  ordinarily  be 
laid  down  for  the  prevention  of  overcrowding.  In  a  certain  class  of  modern 
hotel,  where  convenience  of  detail  has  been  sacrificed  to  external  appearances, 
the  size  of  the  windows  is  so  large,  and  indeed  out  of  all  proportion  to  the 
size  of  the  rooms,  that  much  difficulty  is  experienced  in  opening  them,  and 
consequently  there  is  a  tendency  to  keep  them  permanently  shut ;  a  tendency 
which  is  encouraged  by  the  chamber-maid's  desire  to  prevent  the  entry  of 
dust  and  soot,  with  which  the  atmosphere  of  our  larger  towns,  such  as 
Birmingham,  Manchester,  Sheffield,  Leeds,  &c.,  is  so  loaded. 

The  fifth  class,  concerning  as  it  does  the  millions,  is  necessarily  the  most 
numerous  of  any  class  of  separate  dwelling.  It  is,  moreover,  the  class  that 
may  be  said  to  call  for  more  control  and  supervision  than  any  other  class  of 
dwelling,  since  the  comparatively  small  cost  of  each  dwelling  affords  a  larger 
scope  for  building  speculation  than  in  the  ease  of  more  costly  dwellings.  At 
the  same  time  it  must  be  admitted  that  a  vast  amount  of  good  has  been,  and  is 
still  being,  done  by  philanthropic  individuals  and  societies  to  provide  v/hole- 
some  and  decent  dwellmgs  for  this  large  class  of  the  community,  both  in 
town  and  country.  In  this  respect  the  wage-earning  classes  are  more 
fortunate  than  that  stratum  of  the  lower  middle  class,  which  is  composed  of 
persons  who  earn,  as  yearly  salary  or  income,  scarcely  more  than  is  paid  in 

'  An  instance  has  come  under  the  notice  of  the  writer  where  in  a  well-known  and 
reputable  tavern-hotel  the  night  porter  occupied  by  day  the  same  bed  that  a  lad  in  the 
service  of  the  hotel  occupied  by  night. 

VOL.  I.  XX 


674  HYGIENE 

weekly  wage  to  many  a  jobbing  mechanic,  but  who  is  nevertheless  obliged  to 
keep  up  some  appearance  of  gentihty.  For  while  the  artizan  and  mechanic 
can  choose  a  dwelhng  either  in  a  sort  of  town  of  well-built  houses,  or  in  a. 
block  of  so-called  'industrial  dwellings,'  specially  erected  for  his  class  under 
the  competent  professional  supervision  furnished  by  the  aid  of  some  admi- 
rably administered  building  society  or  philanthropic  association  formed  for  the 
special  purpose  of  providing  cheap  and  good  houses  for  this  class,  the  clerk, 
the  draughtsman,  the  poor  clergyman,  and  a  host  of  others  of  that  class,  are 
obliged  to  seek  a  house  among  those  erected  almost  exclusively  by  speculating 
builders,  with  only  indifferent  supervision,  and  the  majority  of  which  have 
been  built  under  no  sort  of  skilled  professional  advice  whatever.  There  are,, 
it  is  true,  many  dwellings,  modern  as  well  as  old,  occupied  by  the  wage- 
earnmg  community  which  from  various  causes  are  sadly  defective  in  some  of 
the  most  important  features  of  good  hygienic  arrangement,  but,  as  a  general 
rule,  an  amount  of  professional  skill,  both  medical  and  architectural,  is  now- 
adays brought  to  bear  upon  the  modern  artizan's  dwelling  which  is  leading 
to  enormous  improvements  in  construction  and  arrangement.  This  is  partly 
due  to  the  general  progress  of  sanitary  knowledge  as  regards  details  of  con- 
struction, and,  in  its  larger  bearing,  to  the  various  Acts  of  Parhament  which 
have  been  passed  by  the  Legislature  in  obedience  to  the  demands  of  public 
opinion  for  increased  facilities  for  effectually  dealing  with  so  important  a 
subject.  As  regards  the  latter,  some  improvement  has  unquestionably  resulted 
from  the  application,  during  the  period  between  1870  and  1890,  of  what  were 
popularly  known  as  Torrens's  Acts  '  and  Cross's  Acts.^  Some  earlier  Act& 
for  similar  purposes,  known  as  Shaftesbury's  Acts,  had  been  passed  as  long 
ago  as  1851,  but  these  had  never  been  put  into  operation,  and  remained 
always  a  dead  letter.  All  those  Acts  applied  mainly  to  London  and  to 
certain  urban  districts  in  the  provinces.  Torrens's  and  Cross's  Acts,  how- 
ever, were  found  to  involve  serious  cost  and  such  cumbersome  and  slow 
proceedings  that  numerous  instances  arose  where,  notwithstanding  urgent 
need  for  improvement,  it  was  found  almost  impossible  to  apply  them. 
Accordingly,  the  Housing  of  the  Working  Classes  Act,  1890  (53  and  54  Vict, 
cap.  70)  was  passed,  in  order  to  consolidate  the  laws  and  to  simplify  the 
procedure  which  had  to  be  taken  under  the  previous  Acts,  and  under  this 
new  Act  the  powers  of  improvement  have  been  extended  to  rural  sanitary 
districts,  where  the  local  authorities  are  to  exercise  them,  under  the  super- 
vision of  the  County  Councils. 

The  provision  of  healthy  and  convenient  dwellings  for  the  wage-earning 
community  has  exercised  the  attention  and  ingenuity  of  philanthropists  and 
others  in  our  own  country  as  well  as  in  certain  foreign  countries  for  now 
nearly  half  a  century.  Li  England  shortly  after  the  constitution  of  the  Poor- 
law  Commission  in  1834,  following  as  this  did  soon  after  the  first  visi- 
tation of  epidemic  cholera  to  this  country  in  the  year  1832,  the  subject  of 
the  sanitary  condition  of  the  labouring  classes  attracted  much  attention 
owing  in  a  great  measure  to  the  statements  made  in  the  early  annual  reports 
of  the  Commissioners  as  to  the  prevalence  of  disease  among  those  classes  ; 

'  Mr.  Torrens's  Acts  comprise  the  following,  viz.  31  &  32  Vict.  c.  130  (The  Artizans 
and  Labourers'  Dwellings  Act,  1868)  ;  42  &  43  Vict.  c.  64  (The  Artizans  and  Labourers' 
Dwellings  Act  (1868)  Amendment  Act,  1879) ;  43  Vict.  c.  8  ;  and  Part  II.  of  45  &  46 
Vict.  0.  54  (The  Artizans'  Dwellings  Act,  1882). 

^  Sir  Richard  Cross's  Acts  comprise  the  following :  viz.  38  &  39  Vict.  c.  36  (The 
Artizans  and  Labourers'  Dwellings  Improvement  Act,  1875)  ;  42  &  43  Vict,  c  63  (The 
Artizans  and  Labourers'  Dwellings  Improvement  Act,  1879)  ;  and  Part  I.  of  45  &  46  Vict.. 
c.  54  (The  Artizans'  Dwellings  Act,  1882). 


THE  DWELLING  675 

and  in  1842  an  important  report  upon  the  whole  subject  compiled  by  their 
secretary,  the  late  Mr.,  afterwards  Sir,  Edwin  Chadwick,  K.C.B.,  was  issued. 
The  press  took  up  the  subject,  and  notably  the  '  Builder,'  under  the  able 
editorship  of  the  late  Mr.  George  Godwin,  F.E.S.,kept  the  matter  well  before 
the  public,  losing  no  opportunity  of  describing  the  grave  sanitary  state  of 
dwellings  generally,  and  those  of  the  poor  in  particular,  and  of  advocatmg 
reform  and  improvement.  In  1844  a  society,  having  the  late  Prince  Consort 
aa  president,  was  formed  for  improving  the  condition  of  the  labourmg 
classes,  their  prime  object  being  to  provide,  either  by  alteration  or  adapta- 
tion, suitable  dwellings  for  those  classes.  In  1851  this  society  erected  at 
the  International  Exhibition  in  Hyde  Park  an  excellent  model  block  of  four 
dwellings  which  was  subsequently  re-erected  at  Kennington,  where  it  may 
still  be  seen.  Other  societies,  such  as  the  Industrial  Dwelhngs  Company,  of 
which  Sir  Sydney  H.  Waterlow  is  chairman,'  and  the  Artizans',  Labourers', 
and  General  Dwelhngs  Company  have  since  been  formed  for  providing  suit- 
able dwellings  for  the  wage-earning  classes,  and  the  trustees  of  the  funds 
provided  by  the  munificence  of  the  late  Mr.  Peabody  have  also,  since  1862, 
when  they  commenced,  done  much  for  providing  improved  dwellings  for 
these  classes  in  the  metropolis.  In  the  provinces  various  large  employers  of 
labour  have  made  great  efforts  to  provide  their  employes  and  others  with 
good  dwellings  :  this  is  especially  the  case  at  Saltaire,  near  Bradford,  where  a 
very  complete  town  has  been  provided  by  the  late  Sir  Titus  Salt.  This  town 
includes,  besides  dwellings  for  several  hundred  workpeople,  a  church,  schools, 
lecture-room,  library,  baths  and  washhouses,  &c.  At  Akroydon,  near  Halifax, 
a  somewhat  similar  village  has  been  constructed  under  the  auspices  of  Mr. 
Edward  Akroyd  in  conjunction  with  the  Halifax  Permanent  Benefit  Building 
Society ;  and  at  West  Hill  Park,  Halifax,  a  similar  scheme  has  been  carried 
out  by  the  co-operation  of  the  landowner  (the  late  Sir  John  Crossley)  and  the 
Building  Society,  under  which  the  workman  may  become  the  owner  of  a  well- 
built,  wholesome  house  on  very  advantageous  terms.  At  Liverpool,  Barrow- 
in-Furness,  Newcastle-on-Tyne,  and  other  busy  manufacturing  towns, 
much  has  been  done  in  a  similar  way  for  the  better  housing  of  the  labouring 
classes. 

On  the  Continent  corresponding  efforts  were  made  for  the  same  object. 
In  Paris  the  Emperor  Napoleon  HI.,  while  President  of  the  Eepubhc, 
caused  to  be  erected,  in  1849,  what  was  called  a  cite  ouvriere — a  huge 
barrack,  situated  in  the  Rue  Eochechouart — a  scheme,  however,  which  did  not 
prove  very  successful  in  any  way,  as  the  workpeople  disliked  being  caserne, 
or  barracked.  In  1852  a  sum  of  ten  million  francs  was  allotted  by  the 
Government  for  the  amelioration  of  the  labourers  in  the  great  manufac- 
turing cities  of  France,  and  with  this  money  various  improvements  were 
effected  in  their  dwelhngs.  At  Mulhouse  (Alsace),  Mons.  Jean  Dolfus,  an 
eminent  manufacturer,  and  at  the  time  mayor  of  the  town,  started  in  1853  a 
company,  under  the  title  of  the  Societe  des  Cites  Ouvrieres,  with  a  capital  of 
300,000  francs  ;  but  as  the  system  of  housing  the  working  classes  in  these 
vast  '  barracks '  proved  very  distasteful  here  as  at  Paris,  it  was  unanimously 
rejected  by  the  Committee  at  Mulhouse  in  favour  of  a  system  of  detached 
blocks  of  four  houses,  mostly  two  storeys  high,  besides  cellar  and  attic.  This 
Arbeiterstadt,  or  artizans'  colony,  now  comprises  upwards  of  1,000  houses, 

'  In  the  evidence  of  Sir  Sydney  Waterlow  before  the  Eoyal  Commission  on  the  Housing 
of  the  Working  Classes  (1884)  it  is  stated  (Q.  11,909)  that  this  company  alone  had  then 
erected  4,314  tenements,  accommodating  22,000  persons,  while  665  additional  tenements 
for  3,000  persons  were  in  course  of  erection,  the  average  rent  per  room  being  2s.  l^cZ.  per 
week,  which  included  rates,  taxes,  repairs  and  lighting  of  passages,  and  proper  maintenance. 

xx2 


€76  HYGIENE 

each  containing  one  or  two  families  and  provided  with  its  own  small  garden. 
There  are  likewise  a  large  bath-house  and  washing-house,  school  for  infants, 
&c.  The  houses  are  said  to  have  cost  from  120/.  to  150/. ;  each  and  nearly  all 
have  been  sold  to  the  workmen  themselves  at  a  very  slight  profit,  the  purchase 
money  being  repaid  by  instalments.  Similar  schemes  were  carried  out  about 
the  same  time  at  Gebweiler  and  at  Beaucourt  and  elsewhere  in  France.  The 
late  Mr.  George  Godwin,  F.R.S.,  one  of  the  Royal  Commissioners  for  inquiring 
into  the  housing  of  the  working  classes,  m  1884,  in  a  memorandum  appended 
to  their  report,  after  referring  to  the  fact  that  advantageous  arrangements  for 
housing  the  working  classes  by  some  of  the  large  employers  are  made  abroad, 
describes  what  is  known  as  the  famiUstdre  in  connection  with  the  estabhsh- 
ment  of  M.  Godin-Lemaire  at  Guise,  near  St.  Quintin,  in  France,  for  the 
manufacture  of  stoves  and  ranges.  The  workmen — 700  or  800  in  number — 
and  their  families  are  here  housed  in  flats,  three  or  four  storeys  high  :  nur- 
series for  infants,  and  schools  for  the  children  as  they  grow  up,  are  provided, 
and  the  whole  is  stated  to  have  been  carried  on  satisfactorily  and  profitably 
for  about  twenty-five  years.  There  has  thus  been  a  growing  tendency  in 
England  and  France  at  any  rate  to  provide  improved  dwelUngs  for  the 
labouring  classes  in  the  more  populous  areas,  and  this  tendency  has  extended 
into  Belgium  and  certain  parts  of  Germany.  As  regards  the  provision  of 
improved  dwellings  for  the  labouring  classes  in  the  rural  districts  of  the 
United  Kingdom,  this,  where  it  has  been  undertaken  systematically,  has  been 
done  mainly  by  the  landowners,  and,  to  their  credit  be  it  said,  the  owners  of 
extensive  domains  in  the  country  have  put  up  some  excellent  cottages  for 
their  workpeople.  The  Land  Commissioners  have  issued  a  number  of 
sheets  of  plans  for  farm  labourers'  cottages  which  afford  some  excellent  hints 
as  to  suitable  arrangement  with  strict  regard  to  economy,  some  of  which  are 
shown  in  figs.  116  to  124. 

The  cottage  ordinarily  provided  for  the  agricultural  labourer  is  generally 
semi  or  wholly  detached,  since  they  are  usually  scattered  about  the  estate. 
Rows  of  cottages  are  less  frequently  erected  for  this  class  than  for  the 
artizan  classes,  who  have  to  be  concentrated  in  more  close  proximity  to  their 
work.  The  labourer's  cottage  ought  to  comprise  a  living  room  with  small 
scullery  attached  and  at  least  three  bedrooms,  one  for  the  parents  and  two 
for  the  children.  The  most  economical  arrangement  of  this  accommodation 
is  in  a  two-storey  building,  and  in  that  case  the  loAver  storey  should  have  a  clear 
height  between  floor  and  ceiling  of  at  least  nine  feet  and  the  upper  storey  not 
less  than  eight  feet.  The  living  room  being  the  principal  one,  and  the  one 
to  be  used  by  all  the  inhabitants  in  common,  ought  to  be  as  large  and  com- 
modious as  practicable,  with  a  minimum  floor  area  of  150  square  feet.  In 
this  room  should  be  a  good  cupboard,  lighted  and  ventilated  by  a  separate 
window,  so  that  certain  articles  of  food  may  be  kept  in  it  without  affecting,  or 
being  affected  by,  the  air  of  the  room  itself.  The  scullery  adjoinmg  the  living 
room  should  contain  a  copper  with  furnace,  and  sometimes  also  a  bread  oven, 
likewise  a  sink,  plate-rack,  &c.  Convenient  minimum  dimensions  for  this 
room  are  10  feet  by  7  feet  6  inches.  The  pantry  can  be  entered  through  the 
scullery,  but  must  have  independent  ventilation  direct  to  the  external  air.  On 
no  account  should  it  be  placed  in  an  underground  cellar,  nor  in  the  staircase 
leading  up  from  the  cellar.  It  is  important  that  the  pantry  should  be  open 
to  free  ventilation,  light,  cool  and  dry,  and,  above  all,  well  protected  against 
the  rise  of  ground  air.  The  fuel  stove  is  best  placed  in  a  shed  out  of  doors 
—where  also  should  be  the  necessary  privy  accommodation  and  place  for 
temporary  deposit  of  dust  and  house  refuse.  The  staircase  should  be  so 
arranged  as  to  obviate  the  possibility  of  its  serving  also  as  an  air-shaft 


THE  DWELLING 


677 


Fig.  116. 


up  which  the  vitiated  air  from  the  hving  room  could  ascend  to  the  sleeping 
apartments.  This  is  most  effectually  secured  when  the  hving  room  is 
entered  through  an  enclosed  porch,  which  likewise  gives  access  to  the  stairs, 
as  m  fig.  121.  The 
provision  of  an  adequate 
porch  has  the  further 
advantage  of  affording 
the  entrance  some  pro- 
tection from  the  wea- 
ther, while  it  is  always 
useful  to  the  occupier 
as  a  place  for  removal 
of  outer  clothing,  boots, 
&c.,  in  wet  weather  in- 
stead of  taking  them 
direct  into  the  living 
room.  The  bedrooms 
ought  to  be  as  large 
as  the  circumstances 
permit,  that  for  the 
parents  being  about  12 
feet  by  10  feet  and  pro- 
vided with  a  fireplace 
and  good  cupboard,  and 
the  children's  rooms 
having  a  floor  area  of 
about  80  square  feet 
and  60  square  feet  re- 
spectively ;  and  it  is 
very  desirable  that 
these  rooms  should 
have  fireplaces  in  them. 

Approximately  the 
same  accommodation 
as  last  above  described 
may  be  obtained  in  a 
one-storey  cottage  ar- 
ranged upon  either  of  the 
plans  (figs.  116  to  120). 

The  artizan's  dwel- 
ling involves  greater  dif- 
ficulty of  arrangement 
upon  a  convenient,  ade- 
quate, and  wholesome 
plan  than  the  agri- 
cultural labourer's  cot- 
tage, since  it  is  usually 
necessary  to  place  it 
on  a  site  where  land 
itself  is  of  much  greater 
value  than  agricultural 
land.  It  has  to  be  in  the  immediate  vicinity  of  some  factory,  where  con- 
siderable numbers  of  persons  are  employed,  and  therefore,  if  not  actuaUy  in 
a  town,  it  must  be  in  at  least  a  populous  district.     Hence,  the  necessity  for 


678 


HYGIENE 


Fig.  119. 


crowding  the  dwellings  together  ;  and  so  great  is  this  necessity  that,  not 
only  are  the  dwellings  often  arranged  in  rows  with  streets  of  the  minimum 
width  permissible  in  the  locaHty  in  front  of  them,  and  with  the  smallest  per- 
missible amount  of  open  space  at  the  rear  of  them,  but  in  many  towns  and 

in  the  metropolis,  where 
the  cheapest  land  is 
very  costly  for  the  pur- 
pose, the  houses  have 
to  be  piled  up  in  blocks 
of  building  many  storeys 
in  height.  The  separate 
house  of  the  artizan 
usually  built  in  rows  in 
the  suburbs  of  the  busy 
manufacturing  towns 
(lifters  but  little,  as  re- 
gards accommodation, 
from  the  dwelling  of 
the  country  labourer 
with  a  family,  but  the 
modern  block  of  artizans ' 
dwellings  that  has  de- 
veloped in  the  last  fifty 
years  involves  some 
important  hygienic 

questions  that  can 
scarcely  be  said  to 
apply  in  the  case  of 
separate  dwellings. 

This  type  of  buildmg 
has  undergone  much 
change,  and  many  hy- 
gienic improvements 
have  been  made  in  the 
more  recently  erected 
blocks  of  dwellings. 

In  what  is  probably 
the  first  published  plan 
for  such  a  building,  de- 
signed, in  1841,  by  Mr. 
Sydney  Smirke,'  a  num- 
ber of  separate  dwel- 
lings consisting  of  one, 
two,  or  more  rooms 
each,  are  arranged 
along  both  sides  of  a 
main  corridor  eight  feet 
Avide  in  each  storey  of 
a  three-storey  building 
T)lannea  in  the  form  of  the  letter  E.  A  similar  arrangement  of  dwellings 
alonc^  both  sides  of  a  corridor  was  adopted  in  some  of  the  earlier  blocks 
of  building  erected  by  the  trustees  of  the  Peabody  Fund.  This  plan,  however, 
'  Report  hy  the  Poor-law  Commissioners  on  the  Sanitary  Condition  of  the  Labour- 
i>ig  Population  of  Great  Britain,  p.  274.     Prepared  by  Edwin  Chad^Yick.    London  :  1842. 


Fig.  12a 


Fig.  121. 


THE  DWELLING 


679 


Fig.  122. 


has  now  been  discarded  owing  partly  to  the  dishke  evinced  by  the  inhabitants 
of  the  dwelhngs  to  the  absence  of  privacy  and  independence  that  was  inevitable 
under  the  corridor  arrangement,  and  partly  to  hygienic  objections.  As  regards 
the  latter,  the  corridor 
always  involves  much 
difficulty  in  regard  to 
light  and  ventilation ; 
it  interferes  with  the 
through -ventilation  of 
the  dwellings  along  its 
sides ;  it  leads  to  the 
enclosed  atmosphere  of 
the  whole  building 
being  uniformly  vitiated 
by  the  aggregation  of 
a  large  population,  and 
in  the  event  of  any  in- 
fectious disease  occur- 
ring among  the  inhabi- 
tants of  one  dwelling, 
the  risk  of  its  spread- 
ing, by  means  of  the  cor- 
ridor and  staircases,  to 
the  inmates  of  the  other 

'  dwelhngs  in  the  same 
building  is  very  con- 
siderable. A  further  de- 
fect in  the  earlier  blocks 

'  of  dwellings  was  the  pro- 
vision of  a  water-closet 
as  an  integral  part  of  each 
dwelling,  and  arranged 

in  such  relationship  to 
the    rooms    as     to    be 

more  or  less  a  source  of 

danger  to  health.     The 

>  disposition  of  the  blocks 

•on  the  site  available  for 

them     was    a    further 

point  upon  which  many 

errors  have  been  made, 

for    in   some   instances 

the  blocks,  many  storeys 

high,  have  been  directly 

connected  together  at  a 

right  angle,    and   even 

at   an  acute   angle,   so 

as  to  seriously  interfere 

with  the  free  circula- 
tion  of    air   about  the 

exterior  and  the  access 

of  light  to  many  of  the  rooms.     In  some  instances  the  buildings  have  been 

arranged  continuously  round  a  central  courtyard  with  a  mere  archway,  one  or 

two  storeys  high,  in  one  side  to  give  access  thereto.     These  grave  defects, 


p   U-l   t-»  'M   l-l 


30  Feet 


Fig.  123. 


i-i  t_i  i-j  i-_i  i_j 


30feef 


Fig.  124. 


680  HYGIENE 

which  have  been  found  prejudicial  to  the  health  of  the  inhabitants,  and  to 
increase  the  death-rate,  especially  the  infant  mortality,  have  been  generally 
much  diminished  in  the  more  recently  erected  blocks  of  dwellings.  The  cor- 
ridors have  been  dispensed  with,  and  each  dwelling  is  now  usually  independent 
of  the  others,  so  far  as  enclosed  atmosphere  common  to  all  is  concerned  ;  for 
the  staircases  are  generally  arranged  to  give  access  to  one  vertical  series  of 
dwellings  only  on  each  side  of  them,  and  are  entirely  open  to  the  external 
air.  The  water-closet  accommodation  to  each  dwellmg  is  often  arranged 
so  as  to  be  accessible  from  the  external  air  by  means  of  some  sort  of 
balcony  ;  and  the  blocks  of  building  are  often  wholly  detached,  thus  doing 
away  with  confined  angles  and  stagnant  corners.  These  improved  arrange- 
ments, however,  are  not  invariably  adopted,  and  unless  some  controlling 
authority  is  invested  with  power  to  require  them,  and  to  see  them  carried 
out,  it  seems  probable  that  the  natural  desire  to  provide  numerous  cheap 
dweUings,  at  the  smallest  possible  outlay,  will  induce  many  speculating  builders 
and  others  to  still  erect  huge  blocks  of  dwellings,  piled  up  storey  upon  storey,, 
regardless  of  light  and  air,  and  producing  an  excessive  aggregation  of  human 
beings  under  the  one  roof  and  an  undue  density  of  population  on  area.  This 
has  already  been  referred  to  ;  hence  it  is  only  necessary  here  to  point  out  the 
extreme  necessity  for  insisting  upon  ample  open  space  between  the  blocks  of 
these  dwellings,  and  the  complete  disconnection  of  the  blocks  one  from 
another,  in  order  to  avoid  all  confined  angles  and  to  ensure  the  utmost 
freedom  of  circulation  of  air  about  the  blocks,  and  of  access  of  light  with  a 
certain  amount  of  such  sunshine  as  is  available  in  our  climate  to  every  room 
intended  for  habitation  durmg  a  portion  of  the  day.  If  these  conditions 
are  insisted  upon,  culs-de-sac  will  in  effect  be  prohibited,  and  the  height  of 
the  blocks  on  the  one  hand,  and  the  distances  between  them  and  adjacent 
buildings  or  blocks  on  the  other,  will  have  to  bear  some  relation  the  one 
to  the  other. 

Much  credit  is  often  assumed  by  certain  managers  and  directors  of  existing 
dwellings  of  the  kind  referred  to  for  the  moderate  death-rate  and  rate  of  infant 
mortality  in  the  dwellings,  and  it  is  sought  to  illustrate  the  excellence  of  the 
health  arrangements  of  the  respective  blocks  of  dwellings  by  a  comparison  with 
the  rates  of  mortality  of  the  metropolis  as  a  whole.  But  it  has  to  be  borne  in 
mind  that  the  occupiers  of  these  blocks  of  dwellings  are,  to  a  very  large  extent, 
a  population  specially  selected  for  their  respectability  and  other  good  qualities. 
It  is  generally  admitted  that  these  inhabitants  are  ahvays  socially  far  above  the 
class  of  inhabitants  of  the  insanitary  dwellings  that  were  pulled  down  to 
make  way  for  the  improved  dwellings,  that  the  landlords  of  these  new  dwellings 
naturally  drift  into  the  groove  followed  by  all  landlords  and  get  rid  of  the 
worst  tenants,  and  thus  the  inhabitants  of  these  dwellings  come  to  be  a  picked 
set  of  highly  respectable  families.  With  all  this  in  favour  of  the  health  condi- 
tions of  the  population  of  these  dwellings,  the  difference  between  the  mortality 
rate  in  them  and  in  the  whole  metropoHs  is  often  but  very  little,  especially 
in  regard  to  the  rate  of  infant  mortality.  Thus  it  is  stated,  for  example,  that 
in  a  population  of  between  6,000  and  7,000,  occupying  upwards  of  a  dozen 
different  estates  of  such  dwellings — though  there  was  room  for  more,  many 
of  the  dwellings  being  empty — the  general  death-rate  was  only  15'6per  1,000, 
while  in  the  whole  metropolis  it  was  18" 5  ;  but  in  these  same  dwellings  the 
rate  of  infant  mortality  was  140  per  1,000  births,  or  only  six  less  than  in  the 
whole  metropolis,  where  the  rate  during  the  same  period  was  146  per  1,000 
births.  This  difference  in  so  important  a  matter  as  infant  mortality  seems 
much  smaller  than  should  be  regarded  as  completely  satisfactory. 

There  are  many  points  about  the  dwellings  of  the  artizan  and  labouring 


THE  DWELLING  681 

classes  which,  even  where  they  have  been  erected  otherwise  than  by  mere 
speculators,  call  for  special  attention  and  improvement.  The  customs  of 
the  people  and  the  character  of  the  locality,  moreover,  often  exercise  a  certain 
influence  upon  the  hygienic  arrangements,  for  whereas  in  southern  towns  of 
England  water-closets  are  almost  universal  in  dwellings  of  the  class  under 
consideration,  similar  dwellings  in  the  midlands  and  in  the  northern  counties 
are  frequently  provided  with  some  sort  of  privy  or  dry  system  of  closet.  It  is 
not  at  all  uncommon,  too,  in  the  latter  districts  to  find  the  amount  of  closet 
or  privy  accommodation  in  much  smaller  proportion  than  in  the  south,  and 
such  as  is  provided  is  often  arranged  in  what  would  be  regarded  in  the  more 
southerly  districts  as  very  inconvenient  positions  relatively  to  the  houses  for 
which  they  are  intended.  The  Public  Health  Act,  1875,  in  Sec.  35  prohibits 
the  erection  of  any  house  '  without  a  sufficient  water-closet,  earth-closet,  or 
privy.'  But  Sec.  36  gives  the  local  authority  certain  discretion  in  regard  to 
their  judgment  of  the  sufficiency  of  closet  accommodation  where  a  closet  or 
privy  has  been,  is,  or  may  be  used  in  common  by  the  inmates  of  two  or  more 
houses,  and  accordingly  houses  for  the  artizan  and  labouring  classes  are 
sometimes  erected,  even  under  the  authority  of  town  councils  and  other 
local  sanitary  authorities,  which  have  only  one  closet  to  every  two,  three, 
and  sometimes  even  four  houses,  the  closets  thus  provided  being  placed  in 
groups  in  one  yard  common  to  all  the  houses  in  which  the  children  play,  the 
women  hang  out  their  linen  to  dry  after  washing,  and  the  men  and  boys 
loiter  about.  The  objections  to  these  arrangements,  quite  apart  from  the 
question  of  decency  and  morals,  are  serious  from  a  hygienic  point  of  view. 
Thus  the  distance  of  the  closet  from  some  of  the  houses  it  serves  is  some- 
times excessive — thirty  or  forty  yards — and  in  some  instances  so  placed  that 
the  occupiers  of  certain  houses  must  come  out  of  their  front  door,  pass  along 
the  street  to  a  passage  leading  through  the  row  of  houses  to  the  privies  in 
the  common  yard  at  the  rear.  It  will  be  obvious  that  such  an  arrangement 
must  tend  to  deter  the  inhabitants  from  using  the  closets  as  freely  as  might  be 
desired,  while  it  certainly  leads  to  the  very  objectionable  practice  of  retaining 
excreta  in  the  houses  until  a  convenient  opportunity  for  carrying  them  to 
the  privies.^  The  arrangement  is  further  objectionable  on  sanitary  grounds, 
since  it  involves  the  use  by  the  inhabitants  of  two  or  three  different  houses 
of  one  privy  in  common,  and  since  this  privy  discharges  into  the  same 
receptacle  as  do  other  privies  which  are  resorted  to  by  the  inhabitants  of 
other  houses.  Under  such  circumstances  infectious  disease  occurring  in 
any  one  of  these  houses  might  possibly  be  communicated  to  the  inhabitants 
of  the  other  houses  through  the  medium  of  these  privies  and  ashpits. 

Another  grave  defect  that  exists  in  many  cottage  dwellings  in  certain 

'  Mr.  Butterfield,  formerly  Medical  Officer  of  Health  for  Bradford  (Yorks),  reports  that 
during  an  epidemic  of  summer  diarrhoea  which  prevailed  in  that  town  in  1878  certain 
houses  in  which  deaths  had  occurred  were  visited,  when  it  was  found  that  the  houses 
fronting  the  street  had  suffered  far  more  from  the  disease  than  those  next  the  backyard, 
in  which  were  situated  the  privies  and  ashpits.  Mr.  Butterfield  goes  on  to  say  :  '  Why 
the  deaths  should  be  twice  as  numerous  in  the  front  houses  than  in  the  back  ones,  which 
face  the  privies  and  ashpits  common  to  both,  is  not  easily  accounted  for  unless  the  more 
ready  access  to  the  conveniences  induces  a  more  frequent  and  prompt  removal  of  the 
excreta  than  is  the  case  in  the  front  houses.  I  have  frequently  remarked  that,  rather  than 
pass  through  the  portions  of  street  and  passage  necessary  to  reach  the  proper  receptacle, 
women  will  conceal  excreta  in  some  obscure  corner  of  the  premises  until  nightfall.  The 
effect  of  thus  contaminating  the  already  sufficiently  close  atmosphere  of  a  back-to-back 
house  is  of  course  exceedingly  prejudicial  to  a  child  suffering  from  the  effects  of  bad  nursing 
and  improper  diet.  More  especially  is  this  the  case  when  the  obscure  corner  before 
mentioned  is  beneath  the  shelf  on  which  the  milk  is  kept.' 


G82  HYGIENE 

districts  where  the  land  is  of  a  very  hilly  character  is  that  of  erecting 
on  the  side  of  a  hill  rows  of  cottages  one  row  directly  over  the  other,  the 
dwellings  in  the  upper  row  fronting  the  rise  of  the  hill  in  one  direction  and 
those  in  the  lower  row  fronting  the  descent  of  the  hill  in  the  reverse  direction, 
with  the  result  that  while  the  houses  in  the  upper  row  have  at  their  rear 
ample  air  space,  though  no  yards,  the  houses  in  the  lower  row  have  neither 
air  space  nor  yard  at  their  rear,  which  generally  abuts  against  the  earth 
beneath  the  street  or  roadway  in  front  of  the  upper  row  of  houses,  and  con- 
sequently the  lower  ones  are  not  only  unprovided  with  any  effectual  means 
of  through-ventilation,  but  are  necessarily  dark  and  damp.  Such  houses, 
new  as  well  as  old,  are  to  be  met  with  in  numbers  of  towns  in  the  hilly 
districts  of  South  Wales,  Yorkshire,  and  elscAvhere. 

For  many  years  past  the  system  of  back-to-back  house  construction  has 
been  condemned  as  being  inconsistent  with  proper  hygienic  conditions,  but  it 
is  curious  to  notice  how  scanty  were  the  actual  reasons  upon  which  this 
general  condemnation  was  based.  True,  the  prevalence  and  intensity  of 
sickness  in  any  town  where  this  class  of  house  was  at  all  common  were  found 
to  be  frequently  greater  in  the  locality  where  such  houses  were  most 
numerous  than  in  other  parts  of  the  same  town,  but  then  the  condition  of 
the  surroundings  of  those  houses  as  well  as  of  the  inhabitants  themselves 
was  generally  sufficient  to  account  in  a  great  measure  for  the  excess  of  sick- 
ness among  them.  This  defective  condition  of  surroundings  was  no  doubt 
largely  due  to  bad  local  administration  consequent  on  the  then  existing  rudi- 
mentary knowledge  of  sanitary  requirements,  upon  the  absence  of  efficient 
laws  for  the  prevention  of  overcrowding,  upon  defective  systems  of  drainage, 
or  possibly  the  total  absence  of  drainage,  and  upon  the  unlimited  amount  of 
the  most  repulsive  filth  and  refuse  in  various  stages  of  putrefaction  that  was 
commonly  allowed  to  accumulate  within,  or  in  close  vicinity  of,  the  dwelling, 
thus  loaduig  the  air  at  all  times  and  under  all  circumstances  with  offensive 
and  mischievous  effluvia. 

Such  were  the  conditions  that  formerly  existed  in  numbers  of  towns, 
particularly  in  the  north  of  England,  where  this  class  of  dwelling  was 
prevalent ;  and  under  such  conditions  it  followed  that  the  habits  of  the 
occupiers  of  such  houses  only  too  frequently  from  their  slovenliness  made 
the  interior  a  counterpart  of  the  exterior.  Great  improvements  in  the 
sanitary  administration  of  towns  have  taken  place  in  recent  years,  and  the 
beneficial  results  therefrom  may  readily  be  perceived  and  are  generally  freely 
admitted,  but  the  actual  sanitary  disadvantages  of  the  system  of  back-to-back 
house  construction  j;er  se,  while  still  generally  admitted,  have  not  hitherto 
received  that  searching  investigation  which  the  subject  deserves  and  which 
is  requisite  in  order  to  demonstrate  the  serious  prejudicial  effect  which  it  is, 
with  good  reason,  believed  to  have  upon  the  occupiers  of  such  houses  and 
the  district  in  which  those  houses  are  built.  That  the  question  deserves 
•serious  attention  can  hardly  be  denied  when  its  magnitude  is  taken  into 
:account.  In  many  towns  this  vicious  system  of  house  construction  is 
permitted  under  local  Acts  of  Parliament ;  in  others  it  is  allowed  under 
some  obsolete  series  of  building  bye-laws ;  and  even  in  the  metropolis, 
where  unfortunately  there  is  but  little  legislation  for  the  sanitary  control  of 
new  buildings,  it  is  not  prohibited,  directly  or  indirectly,  either  by  Act  of 
Parliament  or  by  bye-laws.  Under  these  circumstances,  and  seeing  that  the 
construction  of  back-to-back  houses  tends  to  the  crowding  of  houses  on 
area,  thereby  in  one  sense  enhancing  the  value  of  building  land,  it  is  not 
surprising  to  find  that  the  system,  in  one  form  or  another,  has  been  and  is 
still  extensively  adopted  in  many  places  ;  and  not  only  so,  but  in  neighbouring 


THE  DWELLING  G83 

newly  developed  localities  the  sanitary  authorities  are  often  desirous  of  adopt- 
ing the  same  mode  of  house  construction  in  order  either  to  conform  to  what 
is  regarded  as  a  local  custom,  or  that  house  accommodation  may  be  provided 
for  the  wage-earning  classes  upon  the  same  basis  of  expenditure  and  under 
similar  conditions  as  is  provided  in  the  older  adjacent  district.  From 
statistics  published  in  a  recent  Government  report '  upon  the  subject  it 
appears  that  in  the  borough  of  Halifax,  where  the  erection  of  back-to-back 
houses  is  still  permitted  and  controlled  by  a  local  Act  of  Parliament,  there 
were  2,094  dwelling-houses  of  all  kinds  erected  during  the  eleven  years  187G- 
86,  and  of  these  no  less  than  1,287,  or  61  per  cent.,  were  back-to-back  houses. 
In  Leeds,  again,  where  a  local  Act  permits  and  regulates  the  construction 
of  back-to-back  houses,  the  same  statistics  show  that  during  the  two  years 
ending  August  1887,  out  of  a  total  of  2,311  new  dwelling  houses  of  all  classes 
that  were  certified  as  fit  for  habitation,  no  less  than  1,502,  or  65  per  cent., 
were  of  the  back-to-back  type,  and  it  is  estimated  that  house  accommodation 
of  this  type  had  been  erected  in  the  municipal  district  of  Leeds  during  the 
twelve  years  ending  August  1887  for  the  large  number  of  50,000  persons. 
In  Bradford,  where  the  erection  of  back-to-back  houses  is  likewise  allowed 
and  governed  by  a  local  Act  of  Parliament,  in  the  eleven  years  1876-86  out 
of  a  total  of  7,036  new  houses,  4,486,  or  64  per  cent.,  were  built  on  the  back- 
to-back  system — equal  to  new  house  accommodation  for  a  population  of  some 
20,000  persons. 

In  the  metropolis  it  is  difiicult  to  arrive  at  any  precise  statistics  of  what 
is  being  done  in  the  way  of  erecting  dwellings  unprovided  with  means  of 
through-ventilation,  but  the  various  Acts  of  Parliament  which  control  the 
erection  of  buildings  in  the  London  district  contain  no  provisions  whatever 
that  would  have  the  effect  of  wholly  prohibiting  the  erection  of  back-to-back 
houses.  The  Metropolitan  Building  Act,  1855,  provides,  in  Sec.  29,  that 
every  dwelling  house,  *  unless  all  the  rooms  can  be  lighted  and  ventilated 
from  a  street  or  alley  adjoining,'  shall  have  in  the  rear  or  on  the  side  thereof 
an  open  space  exclusively  belonging  thereto  to  the  extent  at  least  of  100 
square  feet ;  and  this  requirement  is  supplemented  by  the  requirements  of 
Sec.  14  of  the  Amendment  Act,  1882  (45  Vict.  cap.  14),  which  enacts  that  every 
new  building  to  be  erected  on  a  site  not  previously  occupied  in  whole  or  in 
part  by  a  building,  and  intended  to  be  used  as  a  dwelling  house,  shall,  unless 
the  Metropolitan  Board  of  "Works  (now  the  London  County  Council)  other- 
wise permit,  have  directly  attached  to  it  in  the  rear  an  open  space  exclusively 
belonging  to  it  of  an  extent  varying  according  to  the  length  of  its  frontage. 
Thus  if  the  frontage  do  not  exceed  15  feet  in  length,  an  area  of  at  least  150 
square  feet  is  to  be  provided  ;  if  the  frontage  do  not  exceed  20  feet  in  length, 
the  extent  of  the  open  space  at  the  rear  is  to  be  at  least  200  square  feet ;  for 
30  feet  frontage,  300  square  feet ;  and  for  more  than  30  feet  frontage,  the  extent 
•  of  open  space  is  to  be  at  least  450  square  feet.  The  clause  likewise  provides 
that  the  open  space  shall  extend  throughout  the  entire  width  of  the  building, 
-but  allows  the  site  to  be  entirely  covered  by  building  in  the  ground  storey. 

That  these  provisions  are  utterly  inadequate  to  meet  the  requirements  of 
the  present  day  as  regards  open  space  at  the  rear  of  dwellings  as  an  indispen- 
sable condition  to  the  efficient  through-ventilation  of  such  buildings  is  shown 
by  the  fact  that  numbers  of  dwellings  are  continually  being  erected  with  in- 
sufficient open  space  at  their  rear  or  with  no  open  space  at  all.  The  short  pro- 
visions on  the  subject  in  the  Act  of  1855  were  admittedly  inadequate,  as  an 
extension  of  those  provisions  was  included  in  the  Amendment  Act  of  1882  ; 

'  Joint  Report  to  the  Local  Government  Board  of  Dr.  F.  W.  Barry  and  Mr.  P.  Gordon 
-Smith  on  Back-to-Bach  Houses.    London  :  Eyre  &  Spottiswoode,  1888. 


G84  HYGIENE 

but  those  extensions  are  so  framed  as  to  be  of  little  real  use,  as  they  are  map- 
plicable  except  in  the  outskirts  of  the  metropolitan  area,  where  alone  building- 
sites  '  not  previously  built  upon  '  are  to  be  found  ;  and  even  these  extensions, 
which  may  be  waived  at  the  discretion  of  the  controlling  authority,  permit 
of  the  erection  of  a  building  with  a  basement  storey  likely  to  be  used  as  offices 
or  for  habitation  to  which  no  direct  light  could  have  access,  and  air  could 
only  be  got  by  means  of  shafts  and  the  like,  while  the  open  space  at  rear 
would  be  entirely  above  the  level  of  the  ceiling  of  the  ground  storey.  The 
requisite  amount  of  open  space,  moreover,  is  to  be  calculated  according  to  the 
length  of  frontage  instead  of,  as  it  ought  to  be,  according  to  the  height  of 
the  building.  For  all  practical  purposes,  the  requirement  of  the  Building 
Act,  1855,  is  the  only  one  applicable  to  London  proper,  and  accordingly 
dwellings  of  such  shallow  depth  that  all  the  rooms  in  them  can  have  windows 
in  front  are  to  be  found  which  have  been  erected  in  quite  recent  years,  and 
which  present  the  cardinal  defects  of  houses  of  the  back-to-back  type. 

What  the  effect  upon  the  health  of  the  occupiers  of  these  dwellings 
will  be  remains  yet  to  be  ascertained,  but,  so  far  as  has  at  present  been 
observed,  there  is  little  doubt  as  to  the  prejudicial  effect.  From  the 
mortality  tables  prepared  by  Dr.  John  Tatham,  formerly  Medical  Officer  of 
Health  of  Salford,  and  now  of  Manchester,  it  has  been  found  that  in  certain 
streets  and  courts  consisting  of  back-to-back  houses,  unfurnished  with  through- 
ventilation,  tubercular  disease  was  much  more  common  than  in  other  parts 
of  the  same  town,  and  such  disease  occurred  again  and  again  in  the  same 
houses.  From  the  same  mortality  tables  it  is  shown  in  the  Government 
report  already  alluded  to  that  the  rate  of  mortality  from  epidemic  diseases, 
from  phthisis,  from  pulmonary  diseases  other  than  phthisis,  from  other 
diseases,  and  from  diarrho-a  respectively,  increased  in  proportion  to  the 
number  of  back-to-back  houses  in  each  of  the  district  areas  referred  to,  com- 
prising the  whole  of  the  borough  of  Salford  ;  and  although  it  is  possible  that, 
in  the  consideration  of  such  statement,  a  number  of  other  factors  ought  to 
be  taken  into  account  -  such  as  relative  density  of  population  in  the  districts, 
social  status  of  the  inhabitants,  ages  at  death,  &c. — still  the  fact  of  the 
progressive  increase  in  the  death-rates  from  the  several  diseases  mentioned 
is  extremely  suggestive  of  the  greater  unhealthiness  of  the  dwellings  having 
no  through-ventilation.  With  the  information  at  present  available  on  the 
subject,  therefore,  it  is  not  surprising  to  find  that  the  department  of  Govern- 
ment concerned  with  the  matter  refuses  to  confirm  bye-laws  having  for  their 
object  the  regulation  of  the  construction  of  dwellings  unprovided  with 
adequate  means  of  through-ventilation  ;  and,  so  far  as  can  at  present  be 
judged,  it  seems  unfortunate,  in  the  interests  of  health,  that  those  towns  and 
districts  which  already  possess  the  power  of  regulating  such  a  vicious  plan 
of  house  construction — whether  under  an  old  code  of  bye-laws  which  would 
now  be  considered  obsolete  or  under  any  local  Act  of  Parliament — should 
take  no  steps  for  securing  other  regulations  more  in  conformity  with  modern 
views  of  the  subject.  It  is  worthy  of  note  in  connection  with  this  part  of 
the  subject  that  in  the  First  Eeport  (1885)  of  the  Royal  Commission  on  the 
Housing  of  the  Working  Classes  it  is  recommended  that  in  the  rear  of  every 
new  dwelling  house  or  other  building  to  be  controlled  by  rules  ordinarily 
applicable  to  dwelling-houses,  and  whether  in  old  or  in  new  streets,  there  be 
provided  a  proportionate  extent  of  space  exclusively  belonging  to  the  dwelling- 
bouse  or  building ;  that  this  space  be  free  from  erections  from  the  ground 
level  upwards ;  that  it  extend  laterally  throughout  the  entire  width  of  the 
dwelling-house  or  building  ;  that  for  the  distance  across  the  space  from  the 
building  to  the  boundary  of  adjoining  premises  a  minimum  be  prescribed ;. 


THE  DWELLING  G85 

and  that  this  minimum  increase  with  the  height  of  the  dwelling  house  or 
building.  The  Commissioners,  in  making  these  recommendations,  recognise 
the  difficulty  experienced  in  providing  such  open  space  in  the  case  of  towns 
and  districts  already  laid  out,  where  the  value  of  land  has  attained  consider- 
able magnitude  ;  and  they  state  that  the  recommendations  referred  to  must 
be  subject  to  the  limitations  which  would  probably  be  found  necessary  to  pre- 
vent undue  sacrifice  of  property  in  individual  cases  or  in  particular  areas. 

The  common  lodging-house,  regarded  from  a  hygienic  point  of  view,  may 
play  an  important  part  in  the  health  conditions  of  a  locality,  and  for  this 
reason  it  has  been  found  necessary  to  provide  special  means  of  regulating  the 
conduct  of  such  houses.  This  is  the  more  necessary  seeing  that  common 
lodging-houses,  according  to  the  ordinary  acceptation  of  the  term,  are  not 
generally  built  expressly  for  the  purpose,  but  are  more  often,  if  not  always, 
houses  of  large  size  which  have  ceased  to  be  adapted  to  the  altered  circum- 
stances of  the  locality  in  which  they  were  erected,  and  are  taken  over  by  some 
small  capitalist  who  farms  them  out  or  manages  thern  by  '  deputy,'  and  thus 
often  turns  them  to  fairly  lucrative  account.  This  class  of  house,  however, 
■cannot  be  regarded  with  entire  satisfaction,  firstly,  because  such  houses  are 
largely  resorted  to  by  the  '  ne'er-do-well '  class  ;  and  secondly,  because  in 
those  common  lodging-houses  where  accommodation  is  provided  for  mar- 
ried couples  there  is  reason  to  believe  that  the  majority  of  the  men  and 
women,  in  representing  themselves  as  married,  make  a  false  statement. 
The  Public  Health  Act,  1875,  contains  some  very  necessary  and  useful 
provisions  for  the  control  of  common  lodging-houses  with  the  view  of 
diminishing  as  much  as  possible  the  objections  to  them  and  of  rendering 
them  harmless  to  health.  Thus  Section  80  of  that  Act  enacts  that  '  every 
local  authority  shall  from  time  to  time  make  bye-laws  (1)  for  fixing  and  from 
time  to  time  varying  the  number  of  lodgers  who  may  be  received  into  a  com- 
mon lodging-house,  and  for  the  separation  of  the  sexes  therein  ;  and  (2)  for 
promoting  cleanliness  and  ventilation  in  such  houses  ;  and  (3)  for  the  giving 
of  notices  and  the  taking  precautions  in  the  case  of  any  infectious  disease  ; 
and  (4)  generally,  for  the  well  ordering  of  such  houses.'  If  such  bye-laws  are 
made  and  duly  enforced  it  is  clear  that  much  will  be  done  to  render  the 
common  lodging-houses  as  wholesome  and  satisfactory  as  could  be  expected. 

Some  uncertainty  is  supposed  to  exist  as  to  what  houses  are  to  be  included 
in  the  term '  common  lodging-house,'  since  the  Public  Health  Act,  1875,  con- 
tains no  precise  definition  of  the  term.  It  states,  in  Section  89,  that  the 
expression  '  common  lodging-house  '  includes  in  any  case  in  which  only  part 
of  a  house  is  used  as  a  common  lodging-house  the  part  so  used  of  such  house  ; 
but  this  is  far  from  indicating  what  the  term  itself  generally  include?*  The 
question  has  from  time  to  time  formed  the  subject  of  consideration  by  the 
law  officers  of  the  Crown ;  for  as  far  back  as  1853  the  General  Board  of 
Health,  in  a  circular  dated  October  17  of  that  year,  communicated  to  the 
several  local  boards  the  opinion  of  the  law  officers  of  that  day  as  to  the 
meaning  of  the  term  '  common  lodging-house '  in  the  14  and  15  Vict.  cap.  28. 
Those  officers  stated  as  follows  :— 

'  It  may  be  difficult  to  give  a  precise  definition  of  the  term  "  common 
lodging-house,"  but  looking  to  the  preamble  and  general  pro^dsions  of  the 
Act,  it  appears  to  us  to  have  reference  to  that  class  of  lodging-houses  in 
which  persons  of  the  poorer  class  are  received  for  short  periods,  and  though 
strangers  to  one  another  are  allowed  to  inhabit  one  common  room.  We 
are  of  opinion  that  it  does  not  include  hotels,  inns,  public-houses,  or  lodgings 
let  to  the  upper  and  middle  classes.' 

By  that  part   of    the    above   definition  which   refers    to   the   persons 


686  HYGIENE 

inhabiting  a  common  lodging-house  being  '  strangers  to  one  another,' 
the  law  officers  in  a  second  opinion  explained  that  their  '  obvious  intention 
was  to  distinguish  lodgers  promiscuously  brought  together  from  members 
of  one  family  or  household.' 

In  reply  to  the  question  whether  lodging-houses  otherwise  coming  witliin 
the  definition,  but  let  for  a  week  or  longer  period,  would,  from  the  latter 
circumstance,  be  excluded  from  the  operation  of  the  Act,  the  law  officers 
observed :  '  We  are  of  opinion  that  the  period  of  letting  is  unimportant  in 
determining  whether  a  lodging-house  comes  under  the  Act  now  in  question.' 

Since  the- date  of  those  expressions  of  opinion  one  or  two  judicial  decisions 
have  been  given  as  to  what  constitutes  a  common  lodging-house.  One  of 
these  is  specially  deserving  attention,  as  it  points  to  the  conclusion  that  in 
deciding  whether  a  given  house  is  or  is  not  a  common  lodging-house  within 
the  meaning  of  the  Public  Health  Act,  1875,  regard  should  in  each  case  be 
had  to  the  consideration  whether  the  circumstances  of  its  occupation  are  or 
are  not  such  that  supervision  by  the  local  authority  will  be  necessary  in 
order  to  secure  the  needed  cleanliness,  ventilation,  good  ordering,  &c.  For 
the  purpose  of  further  facilitating  the  supervision  of  common  lodging- 
houses,  Sees.  76  to  79  of  the  Public  Health  Act,  1875,  impose  on  every 
sanitary  authority  the  duty  of  keeping  a  register  of  the  common  lodging- 
houses  in  their  district,  and  deal  with  other  matters  relating  to  the  regis- 
tration of  them ;  Sec.  78  provides  that  a  house  shall  not  be  registered  as 
a  common  lodging-house  until  it  has  been  inspected  and  approved  for  the 
purpose  by  some  officer  of  the  local  authority,  and  to  this  inspection  too 
much  importance  can  hardly  be  attached,  since  it  is  essential  that  in  all 
structural  details  the  fitness  of  the  premises  should  be  carefully  ascertained 
before  the  house  is  placed  on  the  register.  The  Local  Government  Board,  in 
their  official  memorandum  accompanying  their  model  bye-laws  with  respect 
to  common  lodging-houses,  suggest  the  following  rules  for  the  guidance 
of  the  inspecting  officer  in  his  examination  of  any  premises  that  it  may  be 
proposed  to  place  on  the  register  :— 

The  house  should  (1)  possess  the  conditions  of  wholesomeness  needed  for  dwelling- 
houses  in  general ;  and  (2)  it  should  further  have  arrangements  fitting  it  for  its  special 
purpose  of  receiving  a  given  number  of  lodgers. 

(1)  The  house  should  be  dry  in  its  foundations  and  have  proper  drainage,  guttering, 
and  spouting,  with  properly  laid  and  substantial  paving  to  any  area  or  yard  abutting 
on  it.  Its  drains  should  have  their  connections  properly  made,  and  they  should  be 
trapped,  where  necessary,  and  adequately  ventilated.  Except  the  soil  pipe  from  a  properly 
trapped  water-closet,  there  should  be  no  direct  communication  of  the  drains  with  the 
interior  of  the  house.  All  waste  pipes  from  sinks,  basins,  and  cisterns  should  discharge 
in  the  open  air  over  gullies  outside  the  house.  The  soil  pipe  should  always  be  efficiently 
ventilated.  The  closets  or  privies  and  the  refuse  receptacles  of  the  house  should  be  in 
proper  situations,  of  proper  construction,  and  adapted  to  any  scavenging  arrangements 
that  may  be  in  force  in  the  district.  The  house  should  have  a  water  supply  of  good 
quality,  and  if  the  water  be  stored  in  cisterns  they  should  be  conveniently  placed  and  of 
proper  construction  to  prevent  any  fouling  of  water.  The  walls,  roof,  and  floors  of  the 
house  should  be  in  good  repair.  Inside  walls  should  not  be  papered.  The  rooms  and  stair- 
cases should  possess  the  means  of  complete  ventilation ;  windows  being  of  adequate  size, 
able  to  be  opened  to  their  full  extent,  or,  if  sash  windows,  both  at  top  and  bottom.  Any 
room  proposed  for  registration  that  has  not  a  chimney  should  be  furnished  with  a  special 
ventilating  opening  or  shaft,  but  a  room  not  having  a  window  to  the  outer  air,  even  if  it 
have  special  means  of  ventilation,  can  seldom  be  proper  for  registration. 

(2)  The  numbers  for  which  the  house  and  each  sleeping  room  may  be  registered  will 
depend  partly  upon  the  dimensions  of  the  rooms  and  their  facilities  for  ventilation  and 
partly  upon  the  amount  of  accommodation  of  other  kinds.  In  rooms  of  ordinary  construc- 
tion to  be  used  for  sleeping,  where  there  are  the  usual  means  of  ventilation  by  windows 
and  chimneys,  about  300  cubic  feet  will  be  a  proper  standard  of  space  to  secure  to  each 


THE  DWELLING-  687 

person  ;  but  in  many  rooms  it  will  be  right  to  appoint  a  larger  space,  and  this  can  only  be 
determined  on  inspection  of  the  particular  room.  The  house  should  possess  kitchen  and 
dayroom  accommodation  apart  from  its  bedrooms,  and  the  sufficiency  of  this  will  have  to 
be  attended  to.  Kooms  that  are  partially  underground  may  not  be  improper  for  dayrooms, 
but  should  not  be  registered  for  use  as  bedrooms.  The  amount  of  water  supply,  closet  or 
privy  accommodation,  and  the  provision  of  refuse  receptacles  should  be  proportionate  to 
the  numbers  for  which  the  house  is  to  be  registered.  If  the  water  is  not  supplied  from 
works  with  constant  service,  a  quantity  should  be  secured  for  daily  use  on  a  scale,  per 
registered  inmate,  of  not  less  than  ten  gallons  a  day  where  there  are  water-closets,  or  five 
gallons  a  day  where  there  are  dry  closets.  For  every  twenty  registered  lodgers  a  separate 
closet  or  privy  should  be  required.  The  washing  accommodation  should,  wherever  practi- 
cable, be  in  a  special  place  and  not  be  in  the  bedrooms  ;  and  the  basins  for  personal 
washing  should  be  fixed  and  have  water  taps  and  discharge  pipes  connected  with  them. 

With  reference  to  the  amount  of  cubic  space  (300  feet)  above  mentioned 
as  a  proper  standard  to  secure  to  each  person  in  rooms  of  ordinary  construc- 
tion, there  must  be  frequent  instances  where  a  larger  amount  is  necessary 
— indeed,  it  is  obviously  impossible  to  lay  down  a  hard-and-fast  rule,, 
since  the  requisite  quantity  of  space  must  depend  upon  a  variety  of  con- 
siderations. In  the  metropolis  the  Commissioner  of  Police  has  a  minimum 
standard,  which  is  determined  in  part  by  the  height  of  the  room,  and  gives 
about  300  cubic  feet  to  each  person  in  rooms  only  used  for  sleeping,  and  which 
are  unoccupied  during  the  day,  inspection  being  also  provided  for  the  purpose 
of  ascertaining  that  ventilation  is  efficiently  maintained.  This  amount  has 
been  decided  upon  in  view  of  the  difficulties  of  lodgment  in  the  metropolis, 
and  ought  certainly  not  to  be  diminished.  When  a  room  is  occupied  both 
by  night  and  by  day  at  least  400  cubic  feet  ought  to  be  obtained  for  each 
inmate,  and  this  only  on  the  assumption  that  ample  means  of  ventilation  by 
open  fireplace  and  windows  (to  open)  are  also  provided.  Where  children 
come  into  consideration,  it  is  common  to  reckon  two  children  under  ten  years 
of  age  as  one  person,  but  this  appears  to  be  an  unfortunate  arrangement,  since 
it  is  desirable  that  a  child  who  is  growing  and  developing  should  have  at 
least  as  much  air  space  as  an  adult. 

As  regards  other  detail  arrangements  bearing  upon  health  in  connection 
with  common  lodging-houses  over  and  above  those  already  referred  to,  it  may 
be  useful  here  to  point  out  that  the  model  bye-laws  of  the  Local  Government 
Board  ^  contain  many  recommendations  on  the  subject.  One  of  these  relates 
to  the  arrangement  of  the  sleeping  accommodation  to  be  provided  for  married 
couples  where  two  or  more  such  couples  occupy  the  same  room,  and  prescribes 
that  each  bed  shall  be  effectually  screened  from  any  other  bed  by  suitable 
partitions.  These  partitions,  which  are  indispensable  in  the  interests  of 
privacy  and  decency,  are  usually  required  to  be  of  wood  or  other  sohd  material^ 
extending,  not  up  to  the  ceiling,  but  to  a  height  of  about  six  feet  six  inches, 
so  as,  while  serving  effectually  to  screen  the  bed,  not  to  interfere  unduly  with 
light  and  ventilation.  They  should  likewise  not  extend  down  to  the  floor,, 
but  should  stop  short  some  six  or  eight  inches  above  the  floor  in  order  to 
admit  of  the  free  movement  of  air  and  to  facilitate  the  cleansing  of  the  whole 
surface  of  the  apartment.  Curtains  are  sometimes  proposed  as  screens,  but 
their  use  for  the  purpose  should  be  avoided,  as  they  are  less  cleanly  than, 
wood  or  sheet  iron,  either  of  which  materials  can  be  more  conveniently  painted 
and  washed.  Moreover,  as  curtains  can  easily  be  either  wholly  or  partially 
withdrawn  at  the  discretion  of  the  lodgers,  their  use  for  the  purpose  of  screen- 
ing and  separating  the  beds  loses  much  value,  and  likewise  renders  it  impos- 
sible to  throw  the  responsibility  of  maintaining  an  effectual  screen  upon  the 

'  Knight's  Annotated  Model  Bye-laws  of  the  Local  Government  Board,  2nd  &  3rd 
Editions.    London :  Knight  &  Co.,  1885  and  1890. 


€88  HYGIENE 

keeper  of  the  house.  Wooden  partitions  as  screens  round  the  bed  of  each 
married  couple  have  long  been  required  in  the  metropolis  by  the  Metropolitan 
Police  Commissioners. 

Over  and  above  what  are  known  as  common  lodging-houses,  there  are 
two  other  classes  of  lodgings  that  demand  special  attention,  namely,  '  cellar 
dwellings  '  and  '  houses  let  in  lodgings,'  both  of  which  are  referred  to  in  the 
Public  Health  Act,  1875.  As  regards  the  former,  Sees.  71  to  75  of  that 
Act  deal  very  definitely  with  the  character  of  such  dwellings,  but  as  regards 
the  latter,  under  Section  90  of  the  Act,  the  control  of  such  houses  is  left  far 
more  in  the  hands  of  the  local  sanitary  authority,  since  they  may  be  empowered 
to  make  bye-laws  for  dealing  with  such  houses  with  the  view  of  enforcing 
such  sanitary  requirements  as  may  be  necessary  in  addition  to  the  numerous 
enactments  of  the  Public  Health  and  other  general  statutes  which  may  bear 
upon  houses  of  this  description. 

As  regards  cellar  dwellings,  it  is  unfortunate  from  a  health  point  of  view 
that  apartments  of  the  kind  should  be  allowed  to  be  occupied  as  dwellings  at 
all.  The  71st  section  of  the  Public  Health  Act,  1875,  prohibits  the  letting 
or  occupation  separately  as  a  dwelling  of  any  cellar  built  or  rebuilt  after  the 
passing  of  that  Act,  and  the  next  section  specially  prescribes  certain  requisitions 
that  must  be  complied  with  in  regard  to  any  cellar  dwelling  whatsoever. 
Amongst  these  requisitions  it  is  laid  down  that  the  cellar  must  in  every  part 
be  at  least  seven  feet  high,  three  feet  of  which  must  be  above  the  surface  of 
the  street  adjoining ;  also  that  a  continuous  external  open  area  two  feet  six 
inches  wide  be  provided  along  the  frontage  of  the  cellar,  the  floor  of  which 
must  be  six  inches  below  the  level  of  the  floor  of  the  cellar ;  likewise  that 
the  cellar  must  be  effectually  drained  by  means  of  a  drain,  the  uppermost 
part  of  which  is  one  foot  at  least  below  the  level  of  the  floor  of  the  cellar  ; 
and  further  that  there  be  appurtenant  to  the  cellar  the  use  of  a  water-closet, 
earth-closet,  or  privy,  and  an  ashpit,  &c.,  and  that  the  cellar  have  a  fireplace 
and  an  external  window  of  at  least  nine  superficial  feet,  to  open  in  an  approved 
manner,  except  in  the  case  of  an  inner  or  back  cellar  let  or  occupied  along 
with  a  front  cellar  as  part  of  the  same  letting  or  occupation,  in  which  case 
the  external  window  may  be  of  any  dimensions  not  being  less  than  four 
superficial  feet  in  area  clear  of  the  sash  frame.  It  will  scarcely  be  alleged 
that  these  conditions  of  letting  or  occupying  cellar  dwellings,  judged  merely 
upon  their  hygienic  merits,  are  otherwise  than  extremely  moderate,  but  they 
are  nevertheless  frequently  infringed.  In  view  of  the  steps  that  have  been 
taken  in  recent  years,  however,  to  provide  improved  dwellings  for  the  poorer 
classes,  it  would  seem  probable  that  at  some  not  very  remote  period,  if  the 
time  has  not  already  arrived,  all  necessity  for  permitting  the  use  of  cellars 
as  dwellings  will  cease,  and  that  vast  numbers  of  such  dwellings  which  now 
scarcely  comply  with  the  statutory  requisitions,  and  which  can  never  be  made 
wholesome,  will  no  longer  be  allowed  to  be  occupied.  In  the  metropolis  the 
requirements  as  regards  cellar  dwellings  have  hitherto  been  slightly  different 
from  those  prescribed  for  the  rest  of  the  country  under  the  Public  Health 
Act,  1875 ;  but  mider  the  Pubhc  Health  (London)  Act,  1891— Sections  96 
to  98 — the  stringency  of  the  requirements  as  regards  underground  rooms 
(hitherto  known  as  cellar  dwellings )  has  been  greatly  increased. 

As  regards  houses  let  in  lodgings,  the  Public  Health  Act  authorises  any 
local  sanitary  authority,  after  certain  preliminary  formalities,  to  make  bye- 
laws  upon  the  undermentioned  matters,  and  under  Section  94  of  the  Public 
Health  (London)  Act,  1891,  the  sanitary  authorities  in  the  metropolis  are 
required  to  make  and  enforce  such  bye-laws  as  are  requisite  in  regard  to 
those  matters. 


THE  DWELLING  689 

(1)  For  fixing  and  from  time  to  time  varying  the  number  of  persons  who  may  occupy 
a  house  or  part  of  a  house  which  is  let  in  lodgings  or  occupied  by  members  of  more  than 
one  family,  and  for  the  separation  of  the  sexes  in  a  house  so  let  or  occupied  : 

(2)  For  the  registration  of  houses  so  let  or  occupied : 

(3)  For  the  inspection  of  such  houses  : 

(4)  For  enforcing  drainage  and  the  provision  of  privy  accommodation  for  such  houses, 
and  for  promoting  cleanliness  and  ventilation  in  such  houses  : 

(5)  For  the  cleansing  and  lime-washing  at  stated  times  of  the  premises,  and  for  the 
paving  of  the  courts  and  courtyards  thereof  : 

(6)  For  the  giving  of  notices  and  the  taking  of  precautions  in  case  of  any  infectious 
disease. 

And  the  Local  Government  Board,  with  the  view  to  assist  local  authorities, 
have  issued  a  series  of  model  bye-laws  bearing  to  a  certain  extent  upon  the 
several  matters  referred  to.  They  have  suggested  the  exemption  from  the 
operation  of  the  bye-laws  of  certain  houses  which,  though  let  in  lodgings  or 
occupied  by  members  of  more  than  one  family,  are  of  such  a  character  as  to 
render  it  inexpedient,  if  not  absolutely  unnecessary,  to  bring  them  within  the 
range  of  bye-laws  having  for  their  primary  object  the  regulation  of  premises 
where  neglect  of  sanitary  requirements  might  otherwise  ensue,  and  accordingly 
a  clause  is  inserted  in  the  model  series  which  provides  for  the  exemption  of 
lodging-houses  as  to  which  it  may  be  reasonably  inferred  that  the  supervision 
by  the  sanitary  authority  which  under  other  circumstances  would  be  neces- 
sary will  be  sufficiently  exercised  by  the  lodgers  themselves.  The  model 
bye-laws  ignore  the  question  of  the  separation  of  the  sexes  as  to  which  the 
statute  authorises  the  making  of  bye-laws,  but  proceed  to  suggest  a  few  simple 
rules  whereby  the  number  of  persons  to  occupy  the  several  sleeping  rooms 
may  be  determined  with  reference  to  the  amount  of  free  air  space  contained 
in  the  rooms.  It  is  suggested  that  in  every  room  used  exclusively  as  a  sleep- 
ing apartment  a  minimum  allowance  of  300  cubic  feet  of  free  air  space  should 
be  afforded  to  each  person  above  ten  years  of  age,  and  150  cubic  feet  of  space 
to  each  child  whose  age  does  not  exceed  ten  years.  In  the  case  of  a  room 
not  used  exclusively  as  a  sleeping  apartment,  these  quantities  of  air  space 
are  increased  to  400  cubic  feet  and  200  cubic  feet  respectively.  The  other 
suggested  clauses  in  the  model  series  relate  to  facilities  for  inspection  ;  to 
the  provision  of  adequate  and  suitable  water-closet,  earth-closet,  or  privy 
accommodation,  which  is  fixed  at  a  rate  of  one  such  closet  to  every  twelve 
persons  sleeping  in  the  house ;  and  to  the  general  maintenance  of  the 
premises,  and  the  several  parts  thereof,  in  a  proper  cleanly  and  habitable 
condition,  and  the  windows  of  the  sleeping  rooms  to  be  regularly  opened  for 
thoroughly  airing  the  rooms  ;  and  likewise  as  to  the  notification  of  any  case 
of  infectious  disease  that  may  be  known  to  have  occurred  in  the  house. 

The  sixth  class,  embracing  dwellings  of  the  institution  type,  has  many 
pecuharities  which  deserve  special  attention.  Thus  the  object  of  each  of 
the  several  kinds  of  institution  must  be  carefully  considered  in  regard  to  the 
particular  hygienic  conditions  that  are  applicable  to  it ;  for  although  some 
of  those  conditions  may  be  important  as  regards  every  type  of  dwellmg,  they 
may  be  more  indispensable  in  one  kind  of  institution  than  in  another.  This 
will  be  better  appreciated  when  it  is  borne  in  mind  that  a  residential  school, 
in  which  children  of  tender  age  pass  nearly  the  whole  of  their  time,  must  be 
so  contrived  as  to  comprise  the  best  conditions  for  establishing  the  physical 
health  and  moral  training,  as  well  as  the  education  of  the  child,  during  the 
eight  or  ten  years  or  more  when  the  constitution  is  forming,  and  the  body  is 
growing  and  developing  ;  at  a  time  when  everything  is  requisite  that  conduces 
to  promote  that  strength  of  body  and  mind  which  is  so  important  in  fostering 
■courage  and  vigour,  and  tends  to  promote   the  higher  quahties — honour, 

VOL.  I.  Y  Y 


690  HYGIENE 

integrity,  and  truth.  For  it  seems  probable  that  untruthfuhiess  is,  in  a 
great  measure,  the  outcome  of  fear  and  timidity,  which  in  its  turn  is  caused 
by  certain  low  conditions  of  vitality.  The  barrack  must  be  adapted  to 
receive  the  adult  man  who  comes  to  it  in  sound  health  to  pass  some  of 
the  best  years  of  his  life,  and  the  conditions  must  be  such  as  will  conduce 
to  the  maintenance  of  his  health  and  strength  so  long  as  he  remains  in 
the  service.  Prisons,  again,  involve  a  variety  of  conditions  according  to 
the  age,  duration,  and  class  of  sentence,  and  other  circumstances  connected 
^\ith  the  prisoners.  The  hospital  must  be  so  contrived  as  to  facilitate  the 
cure  and  expedite  the  discharge  of  the  patient  who  is  brought  to  it,  and 
who  ordinarily  does  not  remain  there  more  than  a  short  period,  rarely 
exceeding  a  few  weeks.  The  asylum,  in  so  far  as  it  has  to  deal  with  curable 
cases,  must  occupy  very  much  the  same  category  as  the  hospital,  but, 
where  it  has  to  deal  "with  those  whose  age  or  condition  renders  the  chance 
of  improvement  or  cure  very  remote  or  hopeless,  would  in  many  ways  come 
in  the  same  category  as  the  workhouse  for  aged  and  infirm,  where  all  that- 
could  be  expected  would  be  ordinary  care  and  attention,  and  such  arrange- 
ment of  buildings  as  would  tend  to  promote  the  comfort  and  to  maintain  the 
general  health  conditions  of  the  patients.  The  workhouse  is  more  or  less  a 
combination  of  residential  buildings  for  the  several  classes  of  indoor  poor  who 
come  under  the  care  of  the  Poor-law  Guardians,  for  the  rearing  of  childi'en 
and  litting  them  to  become  self- supporting  when  grown  up,  for  the  maintenance 
of  the  able-bodied  pauper  in  a  healthy  state  with  such  employment  as  can 
properly  be  exacted,  for  the  proper  care  and  maintenance  of  the  aged,  the 
infirm,  and  the  harmless  imbecile,  with  reasonable  comfort  to  themselves, 
and  for  the  care,  nursing,  and  medical  attendance  of  the  sick. 

In  the  arrangement  of  all  these  buildings  vast  changes  have  taken  place 
in  recent  years,  as  a  result  of  increased  knowledge  of  hygiene  and  of  the  im- 
portant influence  that  improved  conditions  have  upon  the  imnates  of  the 
several  classes  of  institution  mider  consideration. 

PEISONS 

In  modern  times  the  earhest  substantial  efforts  at  improvement  in  the 
arrangement  of  these  institutions  are  those  which  were  initiated  by  John 
Howard  in  regard  to  prisons  and  hospitals.  His  works  upon  the  state  of 
those  institutions,  both  British  and  foreign,  are  standing  records  of  the 
terrible  conditions  existing  at  the  latter  end  of  the  last  century.  So  far  as 
the  prisons  were  concerned,  Howard,  who  first  had  his  attention  drawn  to 
the  subject  when  he  was  Sheriff  of  the  County  of  Bedford,  in  1773,  was 
struck  not  only  with  the  shameful  administration  of  the  prisons  under  which 
those  confined,  both  debtors  and  felons,  were  subjected  to  aU  kinds  of  ill-usages 
and  e\il  practices  at  the  hands  of  the  gaolers  and  other  officers,  but  also 
with  the  general  prevalence  of  what  was  known  as  the  gaol  fever,  the  gaol 
distemper,  and  of  small-pox  in  the  prisons  ;  and  these  diseases  carried  off  by 
death  a  far  larger  number  of  prisoners  who  were  confined  for  offences  of 
comparatively  slight  importance  than  the  actual  number  of  prisoners  who 
suffered  execution  according  to  the  laws  then  m  force.  Writing  of  the  state 
of  the  atmosphere  in  some  of  the  prisons  visited,  Howard  says  :  '  My  reader 
will  judge  of  its  malignity  when  I  assure  him  that  my  clothes  were,  in  m} 
first  journeys  so  offensive,  that  in  a  postchaise  I  could  not  bear  the 
wmdows  drawn  up,  and  was  therefore  obhged  to  travel  commonly  on  horse- 
back. The  leaves  of  my  memorandum  book  were  often  so  tainted  that  1 
could  not  use  it  till  after  spreading  it  an  hour  or  two  before  the  fire ;  and 


THE  DWELLING 


691 


even  my  antidote,  a  vial  of  vinegar,  has,  after  using  it  in  a  few  prisons,  become 
intolerably  disagreeable.' 

This  horrible  condition  of  the  air  of  the  prisons,  together  with  other  gross 
defects  such  as  insufficient  water,  bad  food,  bad  drainage,  and  the  like'^  not 
only  caused  many  prisoners  to  die,  but  a  still  larger  proportion  of  them  were 
seriously  crippled  for  Hfe.  Howard  says  :  '  Certain  it  is  that  many  of  those 
who  survive  their  long  confinement  are  by  it  rendered  incapable  of  working. 
Some  of  them  by  scorbutic  distempers,  others  by  their  toes  mortified,  or 
quite  rotted  from  their  feet,  many  instances  of  which  I  have  seen.' 

_  Some  of  Howard's  recommendations  for  obviating  the  defects  of  the  old 
prisons  when  a  new  one  was  to  be  erected  were  far  in  advance  of  his  time. 
He  says  :  '  That  part  of  the  building  which  is  detached  from  the  (surrounding) 
walls  and  contains  the  men-felons'  ward  may  be  square  or  rectangula'i% 


Fig.  125.— The  Bastille. 


^'  ^ITr^'''  ^J  ^^^  fjf"^  °^  ^*-  I'ltoi'ie ;  B,  Entrance  and  First  Drawbridge ;  c,  Hotel  du  Gouverne- 
ment ;  D  First  Conrt ;  b,  Avenue  leading  to  the  Great  Court ;  p,  Gates  of  the  Great  Court  and 
CoZc^l  r1f>,W,h'p.°.°'?'p'  ^^^f?.i^'  K^"^"*  ^T"  ^^*^'°  ^^^  T'owers  ;  i,  Staircase  leadTng  to  tSe 
ii?i?f  P  />  ^^"^  '^'''  ?°''''°'^  Chamber  ;  l,  Cour  du  Puits ;  M,  Way  to  the  Garden  ;  I,  Steps 
to  the  Garden;  o  Garden;  p.  Fosses;  q,  Passage  to  the  Arseial  Garden;  1,  Tour  du  Pu^?- 
2,  Tour  de  la  Liberty  ;  3,  Tour  de  la  Bertaudifere ;  4,  Tour  de  la  Bazini^re  •  5  Tour  de  la 
Comt6;  6,  Tour  du  Tr6sor  ;  7,  Tour  de  la  Chapelle ;  8,  Tour  du  Coin.  '     ' 

raised  on  arcades  that  it  may  be  more  airy  ; '  and  again,  '  The  infirmary  or 
sick- wards  should  be  .  .  .  raised  on  arcades.'  This  plan  of  raising  the  wards 
on  arcades  or  arches  '  that  they  may  be  more  airy  '  is  now  not  uncommonly 
adopted  in  the  case  of  new  hospitals  in  France  and  Germany,  as  described 
below  under  the  head  of  Hospitals.  In  the  days  when  Howard  was  engaged 
m_  his  inspection  of  prisons  the  numbers  confined  were  but  few  compared 
with  the  numbers  to  be  found  in  the  prisons  of  the  present  day;  for  formerly 
large  numbers  were  transported,  and  many  were  executed,  and  the  large 
majority  of  those  detained  in  the  gaols  or  prisons  were  mere  debtors  and 
persons  committed  for  petty  offences.  The  prisons,  moreover,  were  then  very 
numerous— far  more  numerous,  compared  with  the  population,  than  at  the 
present  day.  And  yet,  notwithstanding  the  small  aggregation  of  prisoners 
in  those  old  prisons,  serious  disease  was  of  most  common  occurrence. 

tt2 


692  HYGIENE 

It  ■uill  be  interesting  here  to  reproduce  the  plan  of  the  Bastille  at  Paris 
(fig.  125),  with  the  description  of  some  portions  of  it  given  by  HoAvard,  as 
supplied  to  him  in  the  form  of  a  pamphlet  published  in  France  in  1774,  but 
immediately  suppressed  : — 

'  The  Castle  is  a  State  prison  consisting  of  eight  very  strong  towers,  surrounded  with  a 
/osse  about  one  hundred  and  twenty  feet  wide,  and  a  wall  sixty  feet  high.  The  entrance 
is  at  the  end  of  the  street  of  St.  Antoine  by  a  drawbridge,  and  great  gates  into  the  court 
of  VHuid  du  Gouvemctncnt ;  and  from  thence  over  another  drawbridge,  to  the  Corps  de 
Garde,  which  is  separated  by  a  strong  barrier  constructed  with  beams  plated  with  iron, 
from  the  Great  Court.  This  court  is  about  120  ft.  by  80  ft.  In  it  is  a  fountain,  and  six 
of  the  towers  surround  it,  which  are  united  by  walls  of  freestone  10  ft.  thick  up  to  the 
top.  At  the  bottom  of  this  court  is  a  large  modern  Cor2)s  de  Logis  which  separates  it 
from  the  Court  du  Pints.  This  court  is  50  ft.  by  25  ft.  Contiguous  to  it  are  the  other 
two  towers.  On  the  top  of  the  towers  is  a  platform  continued  in  terraces  on  which  the 
prisoners  are  sometimes  permitted  to  walk  attended  by  a  guard.  On  this  platform  are 
thirteen  cannons  mounted,  which  are  discharged  on  days  of  rejoicing.  In  the  Cor^M  de 
Logis  is  the  council  chamber,  and  the  kitchen,  offices,  &c. ;  above  these  are  rooms  for 
prisoners  of  distinction,  and  over  the  council  chamber  the  King's  lieutenant  resides.  In 
the  Court  du  Fnifs  is  a  large  well  for  the  use  of  the  kitchen.  The  dungeons  of  the  Tower 
de  la  Liherti  extend  under  the  kitchen,  etc.  Near  that  tower  is  a  small  chapel  on  the 
ground  floor.  In  the  wall  of  it  are  five  niches  or  closets,  in  which  prisoners  are  i^ut  one 
by  one  to  hear  mass,  where  they  can  neither  see  nor  be  seen.  The  dungeons  at  the  bottom 
of  the  towers  exhale  the  most  oiJensive  scents,  and  are  the  receptacles  of  toads,  rats,  and 
other  kinds  of  vermin.  In  the  corner  of  each  is  a  camp  bed  made  of  planks  laid  on  iron 
bars  that  are  fixed  to  the  walls,  and  the  prisoners  are  allowed  some  straw  to  lay  on  the 
beds.  These  dens  are  dark,  having  no  windows,  but  openings  into  the  ditch  ;  they  have 
double  doors,  the  inner  ones  plated  with  iron  with  large  bolts  and  locks.  Of  the  five 
classes  of  chambers,  the  most  horrid  next  to  the  dungeons  are  those  in  which  are  cages 
of  iron.  There  are  three  of  them :  they  are  formed  of  beams  with  strong  plates  of  iron 
and  are  each  8  ft.  by  6  ft.  The  calottes,  or  chambers  at  the  top  of  the  towers,  are  somewhat 
more  tolerable.  They  are  formed  of  eight  arcades  of  freestone.  Here  one  cannot  walk 
but  in  the  middle  of  the  room.  There  is  hardly  sufficient  space  for  a  bed  from  one  arcade 
to  another.  The  windows,  being  in  walls  ten  feet  thick,  and  having  iron  gates  within  and 
without,  admit  but  little  light.  In  these  rooms  the  heat  is  excessive  in  summer  and  the  cold 
in  winter.  They  have  stoves.  Almost  all  the  other  rooms  (of  the  towers)  are  octagons 
about  20  ft.  in  diameter  and  from  14  to  15  ft.  high.     They  are  very  cold  and  damp.' 

If  any  class  of  the  community  need  more  consideration  in  regard  to 
the  hygiene  of  his  dwelling  than  another,  it  assuredly  is  the  inmate  of  our 
prisons.  He  is  compelled  to  occupy  whatever  accommodation  the  authorities 
provide  for  him,  and  to  endure  whatever  conditions  they  may  determine. 
Unlike  the  pauper,  who  when  destitute  may  be  compelled  to  resort  to  the 
workhouse  as  a  dwelling,  he  is  not  permitted  to  communicate  with  the  out- 
side world ;  hence  it  is  of  the  utmost  importance  that  the  health  conditions 
of  our  prisons  should  be,  in  all  respects,  the  best.  As  a  type  of  the  modern 
English  prison,  and  in  striking  contrast  to  the  old  Bastille  of  Paris,  and 
even  to  Newgate  or  the  Penitentiary  of  London,  that  recently  erected  for 
convicts  at  Wormwood  Scrubs,  in  the  west  of  London,  may  be  referred  to. 
Standing  in  a  very  open  situation,  abutting  on  a  large  tract  of  land  that  has 
been  made  over  to  the  public  in  perpetuity  as  a  recreation  ground,  the  prison, 
together  with  the  officers'  quarters  and  various  administrative  buildings, 
occupies  a  site  some  twenty  acres  in  extent.  The  old-fashioned  plan  of 
arranging  the  building  containing  the  prisoners'  cells  in  long  blocks  attached 
to  and  radiating  from  a  central  inspection  block,  such  as  was  adopted  for, 
among  others,  the  Model  Prison  at  Pentonville  erected  fifty  years  ago,  has 
very  properly  been  abandoned,  because  the  blocks  so  placed  involved  the 
formation  of  narrow  and  confined  yards  between  them,  in  which  there  was 
absence  of  light,  stagnation  of  air,  and  consequent  damp  and  unwholesome 
conditions  generally. 


THE  DWELLING 


G93 


The  principle  of  arrangement  adopted  at  the  Wormwood  Scrubs  Prison 
(fig.  126)  is  that  now  followed  universally  in  the  construction  of  every 
large  hospital,  namely,  what  is  known  as  the  pavilion  system.  On  this 
princijple  the  whole  number  of  ordinary  cells  are  divided  up  into  four  dis- 
tinct groups,  making  a  total,  apart  from  infirmary  accommodation,  of  1,378. 
The  four  parallel  pavihons  or  cell  buildings  are  each  four  storeys  high,  the 
two  middle  ones  being  228  feet  apart  and  the  outer  ones  2G2  feet  distant  from 
them.  There  is  thus  ample  space  between  them,  not  merely  for  free  circu- 
lation of  air  and  the  access  of  sunhght  to  both  sides  of  the  pavihons— their 
aspect  being  east  and  west— but  for  exercise  yards  for  the  prisoners  and  for 
sundry  necessary  administrative  buildings  such  as  kitchen  ofiices,  stores, 
bakehouse,  bathhouses  with  fifty-four  baths  for  the  male  and  twelve  for  the 


^'??i, ,?;,,,?., 


Fig.  126. — Block  Plan  of  Wormwood  Scrubs  Prison. 

Cell  Building,  327  cells  ;  B,  CeU  Building,  350  cells  ;  c.  Cell  Building,  350  cells  ;  D,  Cell  Building, 
351  cells ;  b,  Baths  ;  P,  Boiler  House  ;  g,  Bakery ;  h,  Bread  and  Flour  Store ;  mi.  Chapel ; 
I,  Kitchen;  J,  Laundry;  K,  Females' Baths ;  L,  Eoman  Catholic  Chapel;  M,  Matron;  n,  Pho- 
tographer ;  o  O,  Offices  ;  p  p,  Beceptlon  and  Hospital ;  Q,  Clothes  Store  ;  R,  Coal  Store ;  s,  Dead 
House ;  t.  Warders'  Mess  ;  V,  Steward's  and  Manufacturer's  Store ;  v,  Artificers'  Shops ;  W, 
Entrance  Building ;  x.  Officers'  Reading  Room ;  Y,  Warders'  Quarters ;  z,  Governor's  House ; 
A  A,  Superior  Officers'  Quarters. 


female  prisoners,  laundry  building,  &c.  The  cell  buildings  are  each  48  ft. 
wide  from  outside  to  outside,  and  each  consists  of  a  central  hall  or  corridor 
16  ft.  wide,  extending  throughout  its  entire  length,  lighted  from  the  ends  and 
roof,  with  iron  galleries  about  3  ft.  wide  at  each  of  the  upper  floor  levels, 
giving  access  to  a  row  of  cells  along  each  side.  The  cells  are  each  13  ft.  deep, 
7  ft.  wide,  and  9  ft.  high  to  the  highest  part  of  the  arched  ceiling,  and  conse- 
quently contain  fully  800  cubic  feet  of  space.  They  are  each  hghted  by  a 
window  about  3  ft.  6  in.  wide  by  2  ft.  high,  glazed  with  fluted  glass,  of  which 
about  one-seventh  is  made  to  open  as  a  hopper,  by  means  of  which  a  small 
quantity  of  fresh  air  can  be  admitted  at  the  discretion  of  the  prisoner  du'ect 
from  the  outside;  but  as  this  is  fully  7  ft.  above  the  floor  level  of  the  cell, the 
prisoner  has  no  ready  access  to  the  opening  except  by  a  lever  handle  within 


694 


HYGIENE 


his  reach.  The  constant  ventilation  of  each  cell  is  effected  by  a  couple  of 
flues  in  the  end  walls :  one  of  such  flues  brings  into  the  cell  a  supply  of  fi'esh 
air  which  can  be  warmed  by  heating  apparatus  and  pipes  beneath  the  main 
gallery  floor,  and  the  other  drawing  ofl"  the  vitiated  air  into  a  trunk  in  the 
roof  leading  to  a  turret  in  which  an  upcast  current  is  induced  by  a  fire  con- 


ROAD    FROM    NANTERRE    TO    .'iT.    DEM.i. 
Fig.  127.— Block  Plan  of  Prison  at  Nanterre. 

stantly  burning.  The  outlet  for  vitiated  air  is  a  grating  about  18  by  9  in. 
into  a  flue  in  the  external  wall,  about  12  in.  above  the  floor  level,  and  the 
inlet  for  fresh  air,  warmed  when  necessary,  is  a  similar  grating  into  a  flue  in 
the  corridor  wall  about  7  ft.  above  the  floor  level.  Artificial  light  is  given 
by  a  ventilated  gas  burner  in  the  thickness  (18  in.)  of  the  corridor  wall  with 


THE  DWELLING  695 

a  ground  glass  panel  next  the  cell.  Each  cell  is  furnished  with  a  couple  of 
shelves  in  one  corner,  a  fixed  table  immediately  beneath  the  gaslight,  a  stool 
seat,  a  movable  plank-bed  which  is  stood  up  on  end  during  the  day,  with  a 
mattress  and  such  bedding  as  the  season  may  render  necessary,  a  tin  urine 
pot,  a  can  of  water  and  wash-hand  bowl ;  also  a  tin  mug  for  drinking, 
a  bell-push  with  indicator  in  the  corridor,  and  sundry  minor  articles.  The 
floor  is  boarded  and  the  walls  painted  for  about  5  ft.  of  the  height,  the 
remainder  of  the  walls  and  the  ceiling  being  whitewashed.  It  was  formerly 
the  invariable  practice  to  fix  in  each  cell  not  only  a  wash-hand  basin  with 
waste  pipe  and  cold  water  supply,  but  a  water-closet  apparatus.  This, 
however,  has  now  been  entirely  dispensed  with.  A  water-closet  and  a  slop- 
sink  closet  are  provided  at  four  different  points  on  each  floor,  but  these 
water-closets  are  rarely  used  by  the  prisoners,  who  are  not  allowed  to  leave 
their  cells  after  being  locked  up  at  night,  and  ordinarily  use  the  latrines  out 
of  doors  during  the  day. 

In  addition  to  the  cell  buildings  there  is,  for  each  sex,  a  block  of 
reception  wards  where  prisoners  on  first  arrival  are  seen  by  the  medical 
officer,  and  the  requisite  hospital  wards.  The  latter  comprise  accommoda- 
tion for  fifty  men  and  twenty-nine  women.  The  men's  wards  consist  of 
thirty  cells,  including  two  padded  rooms,  and  two  associated  wards  of  ten  beds 
each  ;  the  women's  accommodation  comprises  six  cells  and  two  associated 
wards — ten  and  five  beds  respectively — a  lying-in  ward  for  four  patients 
and  an  isolated  ward  for  four.  The  amount  of  cubic  space  allotted  to  the 
patients  in  the  hospital  cells  is  1,400  ft.,  but  in  the  associated  wards,  which 
are  not  often  more  than  half  full,  a  much  larger  amount  of  space  is  available. 
The  buildings,  which  have  been  erected  by  convict  labour,  are  exceedingly 
well  constructed,  and  it  will  be  seen  that  the  conditions  under  which  the 
prisoners  are  housed  leave  nothing  to  find  fault  with.  It  might  perhaps  be 
contended  that  350  is  a  large  number  to  place  together  in  one  pavilion, 
especially  having  regard  to  the  fact  that  many  of  these  undergo  confinement 
in  their  cells  for  twenty-three  hours  out  of  every  twenty-four — being  allowed 
out  for  one  hour  of  exercise  daily — for  some  nine  months  after  their  first 
admission.  But  looking  to  the  large  amount  of  air  space  afforded  them,  and 
to  the  unceasing  removal  of  vitiated  air  and  renewal  of  fresh  air  that  goes  on 
in  every  cell,  independently  of  any  other  cell,  as  well  as  to  the  minute  attention 
that  is  paid  to  each  prisoner,  there  is  Httle  possibility  of  his  suffering  any 
ill  effects  from  the  conditions  of  residence  in  prison. 

It  is  not  only  in  England  that  the  hospital  plan  of  arranging  prison 
buildings  is  being  adopted.  In  France  the  new  prison  at  Nanterre,^  near 
Paris  (fig.  127),  built  to  hold  1,000  men  and  600  women,  is  arranged  entirely 
in  separate  blocks  or  pavilions.  True,  the  class  of  inmates  is  somewhat 
different  from  that  of  our  convict  prisons,  comprising  as  it  does  prisoners 
in  the  ordinary  sense  of  the  term,  and  mendicants  or  tramps,  together  with 
sick- accommodation  for  both  classes  ;  but  these  are  divided  amongst  sixteen 
distinct  blocks  or  pavihons  connected  together,  and  with  the  chapel  and 
administrative  offices,  by  means  of  covered  ways  open  at  the  sides. 

BAEEACKS 

These  buildings,  like  prisons,  hospitals,  and  other  domicihary  institutions 
whose  fundamental  condition  involves  the  aggregation  of  large  numbers  of 
human  beings,  have  in  the  past  formed  no  exception  to  the  disastrous  results 
that  have  ensued  everywhere  from  the  non-observance  or  neglect  of  those 

*  M.  Hermant,  architect.' 


696  HYGIENE 

hygienic  conditions  -n-liich  are  essential  to  the  maintenance  of  the  inhabitants 
in  a  proper  state  of  health.  In  all  the  greater  nations  of  Europe  the  same  dif- 
ficulties in  regard  to  healthy  dwellings  for  troops  have  been  experienced,  and 
during  the  present  century,  when  standing  armies  have  been  vastly  increased 
in  magnitude,  these  difficulties  have  become  more  accentuated.  In  times  of 
war  the  results  of  either  ignorance  or  neglect  of  the  most  ordinary  rules  of 
hygiene  have,  over  and  over  again,  led  to  the  most  terrible  loss  by  sickness 
and  death.  This,  however,  may  be  to  some  extent  accounted  for  by  the 
exigencies  of  warfare,  the  arrangements  being  perhaps  only  temporary  ;  but 
that  such  results  should  have  occurred  in  times  of  peace,  when  every  arrange- 
ment is  made  with  the  utmost  deliberation,  and  the  buildings  are  provided 
for  the  permanent  dwelling  of  the  men,  is  a  far  more  serious  matter.  The 
lessons  gained  at  so  much  cost,  both  of  life  and  money,  in  various  campaigns 
in  Europe  and  America,  during  the  third  quarter  of  the  present  century, 
have  tended  to  produce  a  universal  reformation  in  barrack  arrangement, 
which,  however,  it  has  mifortunately  not  been  found  practicable  to  fully 
carry  out,  and  consequently,  where  old  barracks  have  been  retained,  even 
though  costly  alterations,  as  palliatives,  have  often  been  effected  in  them, 
evil  results  due  to  the  same  causes  have  still  occurred.  Not  only  has  this 
been  the  case  in  the  British  Possessions,  but  especially  in  France,  Germany, 
Austria,  and  Italy,  with  their  large  armies,  similar  difficulties  have  been 
experienced. 

The  old  French  plan,  advocated  by  Vauban  in  the  middle  of  the  last 
century,  of  forming  a  barrack  for  a  large  number  of  men^ — a  whole  regi- 
ment— in  one  huge  building  arranged  round  the  four  sides  of  a  quadrangle, 
judged  by  our  present  knowledge,  was  bad  enough,  but  it  was  rendered  far 
worse  later  on,  when  owing  to  the  general  increased  strength  of  the  per- 
manent armies,  these  already  huge  buildings  were  enlarged  by  additional 
storeys  or  otherwise,  until  they  would  hold  2,000  or  even  3,000  men. 
Notwithstanding  extensive  systems  of  artificial  ventilation  that  were  in- 
troduced, notably  m  the  Prussian  and  German  barracks  which  had  been 
thus  enlarged,  it  was  found  that  the  rate  of  sickness  and  mortality  invariably 
increased.  Mons.  Toilet,  an  eminent  French  civil  engineer,  who  has  paid 
much  attention  to  the  construction  of  harracks  and  hospitals,  since  he  noticed 
the  deplorable  condition  of  them  while  he  served  in  the  Corps  clu  Genie  during 
the  Franco-German  war,  writes  in  1882  that  during  ten  years  France  lost 
40,000  men  in  the  barracks,  while  some  60,000  men,  who  had  entered  the 
service  in  good  health,  were  discharged  on  account  of  illness  or  infirmity. 
Typhoid  fever  alone  is  said  to  have  killed  12,000  men.  This  disease  and  the 
destructive  lung  disease  commonly  known  as  phthisis  appear  to  have  been 
the  chief  causes  of  this  terrible  loss,  and  the  late  Dr.  Parkes  pointed  out  how, 
in  our  own  barracks,  both  at  home  and  abroad,  as  well  as  in  those  of  many 
other  nations,  these  two  diseases  are  intimately  connected  with  defective 
dwellings,  the  one  pointing  to  bad  drainage  arrangements,  and  the  other  to 
the  constant  breathing  of  an  atmosphere  vitiated  by  respiration. 

In  our  own  country,  previous  to  the  end  of  last  century,  barracks  were 
rarely  constructed,  owing,  among  other  reasons,  to  the  strong  antipathy 
of  the  people  to  support  anything  in  the  shape  of  a  standing  army. 
There  were  a  few  garrisons  for  fortified  towns  and  there  was  the  body- 
guard for  the  protection  of  the  person  of  the  sovereign,  but  there  was 
no  considerable  standing  army.  The  first  barrack  proper  that  was  con- 
structed in  London,  apart  from  that  for  the  garrison  at  the  Tower,  was 
that  built  for  the  Horse  and  Foot  Guards  at  the  Palace  at  Whitehall  on  a 
portion  of  the  site  of  the  present  Horse  Guards.    In  1716,  a  project,  of 


THE  DWELLING  697 

which  the  plans  are  still  preserved,  was  put  forward  by  an  architect 
named  Nicholas  du  Bois,  for  an  immense  barrack  for  some  7,000  men 
to  be  erected  in  Hyde  Park.  It  comprised  a  range  of  buildings  four 
storeys  high,  including  garrets,  1,335  ft.  long,  by  360  ft.  deep,  and  was  to 
stand  near  the  south-east  corner  of  the  Park,  parallel  with  what  is  now 
Park  Lane.  It  enclosed  three  quadrangles,  the  middle  one  being  597  ft.  long 
by  281  ft.  wide,  and  each  of  the  other  two  281  ft.  square  ;  and  the  interior  was 
divided  into  a  multitude  of  small  rooms  of  equal  size  (about  20  ft.  x  20  ft.), 
placed  back  to  back,  and  intended  for  twelve  men  in  each.  The  plans  include 
a  small  infirmary  placed  on  the  south  boundary  against  some  adjacent 
houses  and  with  only  a  northern  aspect,  also  a  chapel  with  (significantly)  a 
graveyard  on  each  side.  This  barrack,  which,  however,  was  never  erected, 
affords  a  fair  sample  of  the  kind  of  building  then  considered  suitable  for  the 
purpose. 

By  1740  a  few  barracks  of  very  makeshift  sort  had  been  erected  in  dif- 
ferent localities,  and  in  1786  a  military  department  was  formed,  and  a  number 
of  barracks  were  hastily  begun,  but  were  speedily  suspended.  Later  on — 
1793-97 — barracks  were  built  in  all  the  more  important  towns,  but  these,  as 
might  be  expected,  were  of  a  very  defective  type.  It  was  not,  however,  until 
after  the  Crimean  war  that  the  whole  subject  of  barrack  accommodation  was 
carefully  studied.  It  was  then  (1857)  found  that  while  the  death-rate  of  the 
civil  male  population,  between  the  ages  of  20  and  40  years,  was  9*8  per  1,000, 
the  mortality  among  the  troops  was  17'11,  or  nearly  double.  The  barracks 
of  the  whole  kingdom  were  examined  and  reported  upon  by  a  special  com- 
mission and  were  found  to  be  defective  in  many  matters  of  primary  import- 
ance, and  this  inquiry  led  to  a  number  of  recommendations,  which  were 
followed  by  regulations  prescribing  the  superficial  and  cubical  space  to  be 
provided  for  each  man  ;  the  abolition  of  the  offensive  urine  tub,  that  had 
invariably  formed  one  of  the  articles  of  furniture  in  every  old  barrack-room ; 
the  provision  of  separate  quarters  for  the  married  men ;  the  provision  of 
baths,  washing  arrangements,  workshops,  reading  and  other  recreation  and 
education  rooms,  and  the  regulating  of  warming  and  ventilation,  water  supply, 
drainage,  and  sanitary  details  generally.  The  beneficial  results  of  this  im- 
proved system  of  barrack  construction  speedily  showed  themselves  in  the 
greatly  diminished  mortality  and  sickness  among  the  men,  for  whereas  in 
1857  the  mortality  of  the  troops  had  been  nearly  twice  as  great  as  that  of 
the  civil  male  population  of  the  same  age,  in  1876  the  mortahty  of  the  troops 
had  been  reduced  to  nearly  2  per  1,000  less  than  that  of  the  corresponding 
civil  male  population  ;  and  the  amount  of  hospital  accommodation  necessary 
for  troops  has  been  diminished  from  10  per  cent,  to  6  per  cent. 

Barrack  construction  for  British  troops  is  necessarily  very  diversified  in 
character,  since  our  soldiers  have  to  be  quartered  in  every  climate  under  the 
sun,  and  what  is  most  suitable  for  our  home  garrisons  would  be  wholly  un- 
suited  either  to  our  tropical  possessions  in  the  Mediterranean,  West  Indies, 
and  India,  or  to  the  climate  of  our  Canadian  Dominion.  In  all  these  cases 
the  amount  of  space  allotted  to  each  man,  and  the  numerous  other  arrange- 
ments for  maintaining  his  health  and  protecting  him  from  the  effect  of 
climate,  have  to  be  specially  considered  according  to  the  particular  local 
circumstances. 

For  the  temperate  climate  of  the  home  countries  the  War  Department 
have  issued  a  series  of  statements  of  the  various  requirements  for  barracks 
for  the  several  branches  of  the  service,  and  in  accordance  with  these  a  large 
.  number  of  barrack  establishments  have  been  erected  in  different  parts  of  the 
kingdom  where  military  centres  have  been  formed  under  the  reorganised 


098  HYGIENE 

arrangement  of  the  home  portion  of  our  army.^  These  modern  barracks, 
which  are  required  to  stand  on  a  site  of  some  ten  acres  in  extent,  exchisive  of 
training  and  encamping  ground  for  mihtia  regiments,  are  for  the  most  part 
planned  upon  the  separate  block  system,  and  comprise  a  number  of  detached 
buildings  so  placed  relatively  one  to  another  as  to  admit  of  ample  circulation 
of  air  about  them,  and  free  access  of  light  and  sunshine.  The  infantry  bar- 
rack for  a  battalion  of  850  rank  and  file  of  eight  companies,  with  its  proper 
proportion  of  officers,  non-commissioned  officers,  and  married  men,  bringing 
the  total  up  to  very  nearly  1,000  of  all  ranks,  with  the  necessary  stabhng  for 
the  field  officers'  horses,  constitutes  a  formidable  establishment  involving 
much  care  in  the  arrangement  of  the  quarters  in  order  to  secure  those 
hygienic  conditions  necessary  for  maintaining  the  men,  women,  and  children 
in  proper  health.  A  cavalry  regiment,  consisting  of  some  80  officers  and 
nearly  650  non-commissioned  officers  and  men,  a  few  being  married,  and 
their  horses,  or  a  battery  of  Eoyal  Horse  or  Field  Artillery,  comprising  some 
six  officers  and  150  non-commissioned  officers  and  men,  with  the  necessary 
troop-horses  and  gun-horses,  is  hkewise  an  assemblage  that  calls  for  excep- 
tional consideration  in  regard  to  the  hygienic  arrangement  of  their  dwellings. 
In  each  of  these  instances  provision  has  to  be  made  for  the  social  and 
recreative  entertainment  and  physical  exercise,  both  of  the  officers  and  men, 
in  order  to  promote  the  maintenance  both  of  mental  and  bodily  health,  and 
arrangements  have  generally  to  be  made  for  dealing  with  cases  of  sickness 
or  casualty,  as  well  as  for  maintenance  of  discipline  and  for  certain  punish- 
ments. For  these  purposes,  besides  the  quarters  for  the  officers  and  the 
men,  married  and  single,  the  complete  barrack  must  comprise  an  officers' 
mess,  bilUard  room,  &c.,  and  rooms  for  mess-man  and  servants,  recreation 
room,  sergeants'  mess,  canteen,  cook  houses,  guard  house  with  cells  and 
prisoners'  room,  &c.,  Hbrary  and  reading-room,  coffee  room,  gymnasium, 
skittle  alley,  fives  court,  chapel-school,  adults'  school,  children's  school,  and 
a  number  of  other  offices  and  outbuildings.  So  far  as  the  residential  part  of 
these  buildings  is  concerned,  much  criticism  has  been  offered  upon  the  absence 
of  day  rooms  and  rooms  m  which  the  men  should  take  their  meals,  the 
^  barrack  rooms  '  alone  being  requu-ed.  According  to  the  statement  already 
referred  to,  in  a  barrack  for  a  regiment  of  infantry,  thirty  such  rooms  are 
prescribed,  each  room  being  77  ft.  long  by  21  ft.  wide  and  about  10  ft.  6  in. 
high.  These  '  barrack  rooms  '  afford  accommodation  for  from  20  to  32  men, 
giving  about  600  cubic  feet,  and  from  57  to  60  superficial  feet  per  man. 
Windows  are  required  to  be  placed  in  the  opposite  side  walls  of  these  rooms, 
about  five  feet  super  of  window  space  (measured  within  the  inside  bead  of 
frame)  being  allowed  to  each  man.  The  beds  are  placed  in  pairs  about 
eighteen  inches  apart  between  the  windows,  with  their  heads  six  inches  from 
the  wall.  It  is  certainly  undesirable  that  meals  should  have  to  be  taken  in 
the  same  room  as  is  used  for  dormitory  purposes,  and  it  would  be  unfortunate 
if  the  men  were  obliged  to  pass  many  hours  of  the  day  in  these  rooms  ;  but 
seeing  that  the  men  are  necessarily  out  of  doors  a  good  deal,  and  that  other 
rooms  and  places  are  pro\'ided  in  which  they  can  read  and  amuse  themselves 
in  a  variety  of  ways  both  physically  and  mentally,  there  is  little  left  for  adverse 
criticism  on  this  head.  The  general  arrangement  is,  in  fact,  an  adaptation  of 
the  plan  now  generally  advocated  for  hospital  buildings.  As  will  be  seen  from 
the  annexed  diagram  (fig.  128),  the  barrack  room  must  have  ample  means 
of  thorough  ventilation  ;  a  urinal,  for  night  use  only,  is  provided  in  a  cross- 
ventilated  projection  from  the  barrack  room  ;  the  ablution  room  is  perhaps 
rather  small  considering  the  number  of  men  to  use  it,  but  it  is  well  fitted  up 
'  The  Military  Forces  Localisation  Act,  1872. 


THE  DWELLING 


69» 


.and  includes  a  foot  pan,  which  is  said  to  be  much  appreciated  by  the  men 

These  blocks  are  restricted  to  two  storeys  in  height,  and,  when  placed  lon- 

,  gitudinally    in    parallel 

rows,   a    clear   distance 

equal  to  at  least  twice 

the  height  of  the  blocks, 

from  the   ground  level 

to  the  eaves,  has  to  be 

provided  between  them. 

The     married       men's 

quarters    are    arranged 

in  a  somewhat  similar 

block,   but    divided    up 

into     thirty-one     inde- 
pendent sets   of  rooms, 

each  set  consisting  of  a 

living-room,     bedroom, 

and  small  scullery,  with 

a  central  staircase  giving 

access  to  an  open  gallery 
on  the  upper  floor,  by 
which  the  several  sets 
of  apartments  in  that 
storey  are  approached. 
The  block  also  includes 
an  infants'  schoolroom 
and  a  class  room. 

The     views     which 
in    this    country    have 
prompted  the  complete 
rearrangement    in    our 
barrack   buildings,    and 
the    results    that   have 
attended  these  changes, 
have  been  duly  noted  in 
certain  other  countries  of 
Europe.  But  it  is  chiefly 
in  France  where  improve- 
ments on  a  large  scale 
are  being   effected.     At 
the  International   Con- 
gress on  Hygiene,  held 
at   Paris   in    1878,   M. 
Toilet,  the  civil  engineer 
already  referred  to,  read 
a  paper  on  '  Les  Loge- 
ments  collectifs,   Hopi- 
taux,  Casernes,  &c.,'  in 
which,     after    referring 
to  the  reform  that  had 
taken    place    and    was 
still   being   carried   out 

Mj^S^^:!t2:%oZ^"^^'''  i-«»<i<»(eo/B„.i.;,  Arcime^.,  Session  1880-81, 


Fig.  128.1 


700 


HYGIENE 


in  the  English  barracks,  and  to  the  large  diminution  of  mortality  and 
sickness  that  had  resulted  therefrom,  he  urged  with  much  force  the  extreme 
necessity  for  similar  reforms  in  France.  In  the  following  year  M.  Emile 
Trelat,  a  well-known  architect,  who  has  done  much  for  hygiene  in  France, 
presented  two  important  reports  to  the  Societe  de  Medecine  Publique,  in  one 
of  which,  after  referring  in  eulogistic  terms  to  the  steps  taken  in  England  under 
the  direction  of  Lord  Panmure  and  Lord  Herbert  to  improve  the  conditions  of 
the  soldier,  he  laid  down  certain  principles  under  which  the  French  barracks 
stood  condemned.  He  pointed  out  that  the  barracks  erected  according  to  the 
plan  adopted  previous  to  1874  contained  conditions  which  threatened  the 
wholesomeness  of  the  buildings,  that  they  held  far  too  many  soldiers  under 
one  roof  ;  that  they  were  unfortunately  composed  of  many  storeys  ;  that  they 
contained  within  the  material  of  the  walls  themselves  dangerous  and  offensive 
matter  which  had  been  absorbed  during  long  periods  of  occupation  without 


^v 1 


P   Y  no  TEC  H  N/E 


M 


a 


M 


»   /      /      /     / 


I 


I// 


H\ 


ED 


^ 


if 


Fig.  129. — Block  Plan  of  Artillery  Barracks  at  Bourges. 

AB,  Entrance  Pavilions;  c  Kitchens:  d,  Infirmary  for  Men;  e,  Latrines;  F,  Punishment  Cells; 
G,  Canteen;  h,  Stables  (ToUet  System);  i,  Stables  (Dock  System);  k,  Veterinary  Infirmary ; 
L,  Drill  Sheds ;  Jl,  Watering  place  for  Horses ;  N,  Lavatory  ;  p,  Reserve  Clothing  Store. 

eflScient  ventilation ;  and  that  the  capacity  of  the  buildings  afforded  insuf- 
ficient cubic  space  per  soldier.  He  continued  that  it  was  most  urgent  that 
this  state  of  things  should  be  altered,  and  advocated  the  system  of  M.  Toilet. 
That  system  was  adopted  at  the  new  barracks  which  were  built  shortly  after- 
wards at  Bourges  (fig.  129)  ;  it  consists  of  a  number  of  detached  blocks,  of 
limited  size  and  only  one  storey  high,  which  afford  a  large  amount  of  cubic 
space  to  each  man,  while  the  aeration  and  ventilation  of  the  interior  is  such 
as  to  prevent  the  absorption  into  the  walls  of  the  offensive  matters  emanating 
from  continued  habitation. 


SCHOOLS 

The  hygiene  of  schools  appears  to  have  received  a  smaller  share  of  atten- 
tion from  the  specialist  than  the  subject  deserves.  There  are  many  valuable 
reports  and  essays  bearing  indirectly  upon  the  subject  and  upon  particular 


THE  DWELLING  701 

aspects  of  it,  but  it  can  hardly  be  said  to  have  been  dealt  with  in  as  wide  and 
'Comprehensive  a  manner  as  is  required.  Hitherto,  so  far  as  the  Education 
Department  of  the  Privy  Council  is  concerned,  no  attempt  appears  to  have  been 
made  to  treat  of  the  hygiene  of  schools  beyond  the  mere  schoolroom  and  its 
accessories,  because  that  department  is  but  little  concerned  with  matters 
other  than  educational.  It  would  seem  that  health  questions  are  at  best  of 
.secondary  importance  there,  and,  if  dealt  with  at  all,  they  are  not  subjected 
to  that  searching  investigation  by  trained  and  skilled  specialists  that  is 
requisite  to  place  them  beyond  doubt. 

The  Association  of  Medical  Officers  of  Schools  has  undoubtedly  done 
good  service  in  dealing  with  certain  questions  of  school  hygiene  ;  but  this 
again  would  seem  to  have  reference  more  to  school  management  and 
administration  and  to  the  means  of  excluding  infectious  disease  than  to  the 
maintenance  of  the  general  health  of  the  residents  ;  and  even  here  the  sub- 
jects are  not  dealt  with  in  their  application  to  those  numerous  residential 
schools  to  which  children  of  the  poorer  classes  are  sent  so  much  as  to  the 
great  public  schools,  which,  as  a  rule,  receive  children  of  superior  constitu- 
tion. In  fact,  many  very  important  questions  bearing  upon  the  arrangement 
and  construction  of  residential  schools  remain  unsettled  and  even  unformu- 
lated. 

There  is  certainly  a  general  consensus  of  opinion  that  the  amount  of 
floor-space  and  cubic-space  commonly  prescribed  for  each  child  in  school- 
rooms is  very  scanty,  notably  in  those  schools  which  come  under  the  inspection 
■of  Government,  or  in  respect  of  which  there  is  a  grant  of  money  calculated 
upon  the  number  of  children  and  the  degree  of  education  attained,  but  no 
serious  effort  has  hitherto  been  made  to  get  that  amount  of  space  increased. 
Meanwhile,  whenever  any  communicable  disease  is  prevalent  in  a  locality — 
isuch  as  measles,  scarlatina,  diphtheria,  &c. — the  village  school  or  the  national 
rschool  is  often  found  to  be  one  of  the  chief  means  of  disseminating  the 
disease.  Although  this  is  frequently  the  case,  it  is  not  invariably  so. 
There  are  instances  where,  in  the  same  locality,  it  is  alleged  that  one  school 
has  been  specially  affected,  while  two  or  three  other  schools,  in  quite  near 
proximity,  have  been  either  very  slightly  affected  or  have  even  escaped  alto- 
gether. If  this  be  so,  there  would  seem  to  be  ground  for  supposing  that  a 
cause  might  be  found  for  the  diffusion  of  the  disease  in  the  one  school  and 
the  whole  or  partial  immunity  of  the  disease  in  the  other  schools.  Can  this 
immunity  be  owing  to  any  difference  in  the  condition  of  the  children  them- 
selves, or  to  better  ventilation  ;  to  a  greater  amount  of  cubic  space  per 
child,  or  to  a  smaller  number  of  children  being  ordinarily  aggregated  together, 
or  to  any  difference  in  the  duration  of  school  hours,  or  to  some  combination 
of  better  conditions  under  which  the  children  in  the  one  or  more  schools  are 
rendered  less  susceptible,  or  the  power  of  attack  possessed  by  the  disease 
is  diminished  or  removed  ?  It  at  least  seems  to  deserve  careful  investiga- 
tion and  skilful  inquiry.  But  this  question  is  referred  to  as  affecting  schools 
intended  for  educational  purposes  alone.  If  so  important  a  matter  applies 
to  those  schools,  how  much  more  important  is  this  question,  and  indeed  a 
number  of  other  questions  that  might  be  suggested,  in  their  bearing  upon 
the  residential  school,  in  which  institution  the  children  not  only  receive 
education,  but  remain,  night  and  day,  for  several  years  ;  in  which  they  sleep, 
feed,  play  and  receive  such  attention  as  is  available  in  case  of  sickness  !  Such 
schools  exist  all  over  the  country,  whether  as  charitable  institutions  for 
orphans  and  afflicted  children,  or  Poor-law  institutions  for  the  children  of 
destitute  persons  and  for  deserted  children,  as  well  as  a  number  of  higher 
class  institutions  of  kindred  purpose.     Very  little,  comparatively,  has  been 


702  HYGIENE 

hitherto  done  in  the  way  of  hterature  upon  this  particular  branch  of  the 
subject.  Schools,  more  especially  residential  schools,  ought  to  be  the  fittest 
place  in  every  respect  for  the  youth,  of  whatever  age  and  of  either  sex. 
Charitable  institutions  and  other  residential  schools  intended  for  the  entire 
care  and  education  of  the  young  are  erected  from  time  to  time,  but  no 
common  plan  or  system  appears  to  have  been  hitherto  advocated.  In  the  case 
of  hospitals  certain  general  principles  of  arrangement  are  now  universally 
recognised.  Not  so,  however,  in  the  case  of  schools  of  the  kind  referred  to. 
They  are  generally  arranged  in  any  fashion  that  may  commend  itself  to  the 
governing  body  for  the  time  being,  and  accordingly  every  conceivable  variety 
of  arrangement  is  to  be  met  with — good,  bad,  and  indifferent  having  been 
alike  adopted  down  to  the  present  moment. 

There  are,  for  example,  numbers  of  large  residential  schools  and  colleges 
for  upper,  middle,  and  lower  classes  throughout  the  country,  some  affording 
accommodation  for  several  hundred  pupils,  in  which  the  chief  building,  con- 
taining the  whole  of  the  administrative,  domestic,  and  educational  depart- 
ments, as  well  as  the  dormitories,  is  arranged  two  or  three  storeys  high  in  the 
form  either  of  the  letter  E  or  the  letter  H,  and  in  some  instances  it  is 
arranged  rovmd  the  four  sides  of  a  quadrangle,  or  perhaps  two  sides  of  the 
quadrangle  are  extended  so  as  to  form  a  second  quadrangle.  Another 
example  is  where  the  school,  though  still  one  large  block  with  projecting 
wings,  is  subdivided  internally  into  groups  of  some  fifty  children  or  more. 
This  is  specially  the  case  at  the  London  Orphan  Asylum  at  Watford.  A 
fui'ther  variety  of  residential  school  is  to  be  found  in  the  Stockwell  Orphan- 
age, London,  where  the  children  occupy  a  row  of  houses  (about  thirty 
children  in  each)  specially  erected  for  the  institution.  The  Home  for  Little 
Boys  at  Farningham  in  Kent,  and  the  Princess  Mary's  Village  Home  at 
Addlestone,  Surrey,  are  examples  of  the  cottage  home  system,  the  houses  of 
the  former  containing  about  thirty,  and  of  the  latter  ten  and  fifteen  children 
each ;  and  the  Philanthropic  Society's  Farm  School  (a  reformatory  school) 
at  Kedhill,  Surrey,  is  another  variety  of  the  same  system,  but  here  the 
several  cottages  contain  an  average  of  some  sixty  boys.  A  somewhat  similar- 
arrangement  is  in  operation  at  many  of  the  great  pubHc  schools  for  boys, 
where  the  masters'  houses  are  scattered  about  the  town,  and  each  contains 
sleeping  and  day  accommodation  for  some  twenty  or  more  boarders.  The 
institutions  that  have  been  erected  under  the  auspices  of  the  Poor-law 
Authorities  might  fairly  be  expected  to  afford  the  best  examples  of  what  such 
schools  ought,  hygienically,  to  be,  since  they  have  been  provided  under  a 
certain  amount  of  continuous  watching  and  supervision  of  the  whole  subject, 
and  with  the  experience  gained  during  many  years  of  systematic  inspection  ; 
but  even  here  no  very  definite  conclusions  appear  to  have  been  arrived  at, 
though  certain  comparatively  recent  experiences  have  led  to  the  condemna- 
tion of  the  principle  of  erecting  a  large  residential  school  in  one  huge 
building.  The  Local  Government  Board  have  certainly  framed  some  useful 
rules  for  the  guidance  of  those  proposing  to  provide  schools  for  pauper 
children,  but  much  latitude  has  been  left — and  wisely  so  at  present — as  to 
the  precise  system  to  be  adopted  in  the  arrangement  of  the  building,  great 
hesitation  being  shown  in  advocating  any  particular  plan. 

The  necessity  for  ensuring  the  best  hygienic  conditions  in  buildings  for 
children,  of  whatever  social  class,  is  more  than  ever  important  now  that  the 
strain  upon  the  child  under  the  modern  system  of  education  is  so  much 
greater  than  formerly,  and  consequently  everything  that  may  conduce  to 
counteract  this  strain  and  pressure  of  education  is  indispensable,  whether  it 
concern  the  internal  arrangements— the  dormitories,  the  school  and  class- 


THE  DWELLING  70S 

rooms,  the  play  and  other  day  rooms  and  industrial  work-rooms — or  the 
external  arrangements,  such  as  the  playgrounds,  playsheds,  gymnasia,  cricket 
fields,  and  other  outdoor  provisions  for  recreative  and  physical  training 
and  exercise.  As  regards  these  latter,  it  has  to  be  borne  in  mind  that  in  pro- 
portion as  the  children  belong  to  the  lower  grades  of  society,  so  do  they 
require  greater  inducements  to  take  physical  exercise — indeed,  it  has  truly 
been  said  by  Mr.  Nettleship,  F.R.C.S.,  that  children,  especially  those  of  the 
poorer  classes,  will  no  more  take  spontaneously  to  recreative  exercises  and 
games  than  they  will  spontaneously  learn  to  read  orwrite.  Both  Mr.  Nettleship 
and  Dr.  F.  J.  Mouat  before  him  have  pointed  out  that  the  children  of  the  lower 
classes  must  be  taught  to  play  games  out  of  doors,  to  swim,  and  otherwise  to 
take  active  exercise.  While  in  the  high  class  public  schools  the  boys  have  a. 
sort  of  hereditary  liking  for  games  involving  considerable  physical  exertion,  and 
which,  by  means  of  permanent  clubs,  are  perpetually  kept  up,  the  children  in 
the  schools  of  the  poorer  classes  are  more  apathetic,  and  unless  the  teaching 
staff  systematically  teach  the  children  how  to  play  and  enter  into  the  games- 
with  them,  there  will  almost  certainly  be  a  strong  tendency  on  the  part  of  the 
children  to  idle  about  the  most  objectionable  parts  of  the  yards  and  places 
provided  for  them  to  play  in,  the  result  of  which  is  likely  to  be  the  reverse  of 
beneficial,  and  to  induce  a  prejudicial  habit  of  loafing,  and  this  notwithstand- 
ing that  every  requisite  for  games  is  provided.  A  further  point  that  is  often 
insufficiently  appreciated  in  the  laying  out  of  schools  of  the  class  referred  to 
is  the  secondary  consideration  that  is  given  to  the  extent  and  suitabihty  of 
the  recreation  grounds,  since  it  not  uncommonly  happens  that  the  larger 
portion  and  better  situated  land  is  set  apart  for  purposes  of  profit  in  the 
shape  of  potato  and  cabbage  gardens,  farming,  &c.,  instead  of  being  regarded 
as  primarily  requisite  for  recreative  outdoor  exercise  by  the  children.  And 
this  tendency  to  exaggerate  the  importance  of  farming,  to  the  sacrifice  of  the 
physical  exercise  of  the  children,  is  fostered  by  the  circumstances  that  the 
superintendent  of  the  institution  is  often  able  to  show  a  considerable  profit 
upon  his  farming  account  for  the  year,  and  thus  he  becomes  converted  from 
a  school  superintendent,  whose  first  care  should  be  for  the  children  com- 
mitted to  his  charge,  into  a  mere  farm  bailiff. 

As  regards  the  hygienic  conditions  that  have  to  be  observed  in  the- 
arrangement  of  the  residential  school  building  itself  in  which  children  have 
not  only  to  be  educated,  but  maintained  and  cared  for  during  every  condition 
of  health  and  sickness  that  may  occur  from  early  infancy  until  they  are 
able  to  go  out  into  the  world  to  earn  their  own  living,  it  is  not  too  much  to 
say  that  the  principles  usually  apphcable  to  hospitals  are  equally  appli- 
cable to  such  schools.  The  child  may  fairly  be  regarded  as  a  most  sensi- 
tive instrument,  which  indicates  very  promptly,  and  with  much  precision,, 
any  variation  of  the  health  conditions  under  which  he  is  placed. 

The  only  class  of  such  institution  that  has  hitherto  been  systematically^ 
under  observation  would  seem  to  be  the  Poor-law  schools  throughout  the 
kingdom.  In  these  schools — chiefly  in  the  larger  ones — a  variety  of  com- 
plaints have  prevailed  amongst  the  children  which  have  formed  the  subject  of 
much  inquiry.  Ophthalmia,  itch,  and  diseases  of  the  skin  and  scalp  have  hung 
about  some  of  these  schools  for  long  periods,  often  with  results  now  known  to- 
be  hfe-long  in  their  prejudicial  influences.  The  mortality  rate  of  these  schools 
is  often  quoted  by  those  interested  in  regarding  them  favourably  as  indicating 
their  good  condition,  but  this  is  a  very  indifferent  test.  A  far  better  one  is 
to  be  found  in  the  rate  of  sickness,  and  this  in  some  instances  has  been 
ascertained  to  be  as  high  as  25  per  cent,  of  the  inmates.  Dr.  P.  J.  Mouat,. 
who  had  large  experience  of  the  Poor-law  schools,  has  pointed  to  a  variety 


704  HYGIENE 

of  affections  that  may  be  fostered  in  some  of  these  schools.^  He  says  :  '  The 
stunted,  impaired  general  health,  and  feeble  bodily  powers  of  too  many  of  such 
children  are  not  removed  or  corrected  by  massing  them  in  large  buildings  or 
groups  ; '  and  he  suggests  that  '  there  is  a  large  and  possibly  increasing  factor 
of  imbecility,  idiocy,  and  nervous  disorders  generally,  and  some  of  the  more 
immetUate  results  of  scrofula  at  the  critical  periods  of  life,  which  may  be  due 
to  the  insanitary  conditions  '  inherent  to  the  aggregation  of  large  numbers  of 
children  in  such  huge  buildings. 

But  the  complaint  that  has  served  most  readily  to  indicate  the  defects  in 
hygienic  arrangement  in  these  schools  has  undoubtedly  been  ophthalmia. 
Instances  could  be  cited  in  which  it  had  prevailed  incessantly  to  an  un- 
fortunately large  extent  for  many  years,  notwithstanding  the  most  indefati- 
gable, skilful,  and  indeed  enthusiastic  attention  of  the  school  authorities  and 
medical  oflBcers  in  charge.  Mr.  E.  Nettleship  has  asserted  that  this  disease  '  is 
the  touchstone  of  the  general  healthiness  of  an  institution.'  He  says,  too  : 
'  Where  many  persons  are  herded  together  their  eyelids  show  sooner  and  more 
certainly  than  any  other  part  if  the  conditions  of  vigorous  health  are  not 
complied  wuth.'  The  disease  was  formerly  common  in  the  army  and  navy, 
but  with  improved  hygienic  conditions  in  the  barracks  and  ships  it  has 
been  practically  abolished.  Travellers  in  the  East  have  always  been  struck 
with  the  remarkable  number  of  blind  persons,  and  poor  people  suffering  with 
ophthalmia,  who  are  met  with  in  all  Oriental  towns  and  villages  where  intense 
crowding  and  other  insanitary  conditions  permanently  exist.  The  intensity 
of  the  disease  varies  much  according  to  the  surrounding  conditions,  but  in 
the  large  Poor-law  schools,  both  provincial  and  metropolitan,  it  has  certainly 
given  much  trouble,  and  accordingly  it  seems  probable  that  advantage  would 
result  from  a  careful  and  systematic  study  of  the  effects  resulting  from  the 
various  arrangements  of  building  that  have  been  tried  in  the  case  of  these 
schools.  In  those  domiciliary  schools  where  the  children  are  usually  of  a 
higher  class,  the  tendency  to  disease  consequent  upon  indifferent  hygienic 
arrangements  may  and  doubtless  does  exist, ^  though  in  a  sUghter  degree  by 
reason  of  a  variety  of  circumstances  such  as  the  superior  condition  under  which 
most  of  the  children  are  reared  before  being  sent  to  school,  and  the  fact  of 
the  children  in  these  schools  having  the  advantage  of  periodical  change 
during  the  three  usual  annual  vacations,  when  they  go  home  or  to  stay  with 
friends.  These  circumstances  would  probably  tend  to  arrest  or  divert  some 
of  the  evil  results  that  might  otherwise  ensue  were  they  to  have  the  same 
continuous  and  uninterrupted  residence  in  school  which  the  children  in  the 
Poor-law  schools  have  necessarily  to  endure.  And  it  seems  probable  that 
the  pallor  and  lassitude  often  noticed  in  children  of  this  higher  class  at  the 
end  of  a  term,  and  which  is  commonly  attributed  to  hard  work  in  school,  is 
in  reality  more  or  less  due  to  the  conditions  of  aggregation  and  defective 
ventilation  referred  to. 

Some  allowance  must  certainly  be  made  for  the  low  standard — mental, 
moral,  and  physical — of  the  majority  of  the  children  of  Poor-law  schools 
when  comparing  them  with  the  higher-class  children  just  referred  to,  and  even 
with  those  of  the  labourer  or  artizan  who  has  struggled  successfully  with 
the  trials  and  inconveniences  of  very  limited  means  ;  but  this  would  scarcely 
diminish  the  usefulness  of  the  investigation  above  suggested.  The  mere 
history  of  Poor-law  schools  is  in  itself  instructive.     In  the  early  workhouses 

'  Paper  on  the  Training  and  Education  of  the  Children  of  tlie  Poor.  Kead  before  the 
Statistical  Society,  April  20,  1880.     London  :  Stanford  &  Co. 

■■^  Mr.  Nettleship,  in  his  licport  on  Ophthalmia  in  the  Metropolitan  Pauper  Schools 
1875,  states  that  he  has  found  the  disease  prevalent  in  certain  other   han  Poor-law  schools. 


THE  DWELLING  705 

of  1835-40  the  children  were  but  imperfectly  separated  from  the  adult  indoor 
paupers.  Later  on,  as  increased  accommodation  for  the  indoor  poor  became 
necessary,  the  children  were  moved  into  a  detached  building  still  situated  on 
the  workhouse  premises  ;  and  gradually  it  was  found  desirable  to  remove  the 
children  altogether  away  from  the  workhouse  wherever  their  number  was 
such  as  to  make  such  a  plan  feasible.  By  degrees  the  children  from  the  large 
workhouses  of  the  metropolis  and  some  of  the  provincial  towns  were  provided 
for  in  separate  institutions  in  the  suburbs — an  arrangement  which  was  un- 
doubtedly a  vast  improvement  in  many  ways.  But  with  the  aggregation  of 
such  large  numbers  of  children— for  in  many  instances  several  Poor-law  unions 
combined,  under  statutory  power,  to  provide  for  the  children  belonging  to  those 
unions  in  one  large  institution — fresh  difficulties  arose,  and  amongst  these  was 
that  of  maintaining  the  children  in  good  health. 

Notwithstanding  the  removal  of  the  children  from  the  more  densely 
populated  areas  in  the  towns  and  metropolis  where  the  workhouses  were 
situated  to  newly  erected  buildings  designed  specially  for  the  purpose,  and 
situated  on  large  sites  in  the  comparatively  open  country,  it  has  become 
only  too  evident  that  this  alone  was  quite  inadequate  to  keep  them  in  a 
proper  condition  of  health.  For  many  years  past  the  children  so  circum- 
stanced have  suffered  repeatedly,  or  more  or  less  continuously,  from  various 
complaints,  but  the  disease  that  has  prevailed  and  given  more  trouble  than 
any  other  has  been  ophthalmia  in  various  stages  of  severity.  And  when 
once  any  complaint  of  that  character  gets  into  an  institution  of  the  kind 
containing  under  its  one  roof  a  vast  number  of  children,  it  has  been  found 
most  difficult  to  get  rid  of  it.  The  best  advice  available  has  been  obtained, 
specialists  have  been  called  in  as  consultants,  and  large  sums  of  money 
have  been  expended  in  the  hope  that  the  complaint  would  be  eradicated 
and  the  health  of  the  children  re-established,  but  with  very  indifferent 
success. 

These  large  institutions  with  vast  aggregations  of  children  have  come 
to  be  regarded  more  or  less  as  failures  ;  and,  as  in  the  case  of  hospitals 
and  other  institutions,  subdivision  of  building,  on  the  principle  of  separate 
pavilions,  is  pointed  to  as  one  of  the  chief  means  of  arresting  the  evils 
complained  of,  and  a  most  important  means  of  preventing  the  recurrence 
of  them.^  Accordingly,  in  recent  years  residential  schools  for  considerable 
numbers  of  children  have  been  arranged  either  in  distinct  blocks  or  pavilions, 
each  to  contain  a  very  limited  number  of  children,  or  upon  what  is  now  known 
as  the  cottage-home  system.  On  both  of  these  systems  many  residential 
schools  have  been  erected  both  under  the  Poor-laws  and  also  for  charitable  pur- 
poses ;  thus  as  an  example  of  the  former  of  these  systems  the  London  Orphan 
Asylum  at  Watford  may  be  referred  to — an  excellent  charitable  institution 
consisting  of  a  number  of  independent  blocks,  attached  or  semi-detached, 
but  without  any  internal  communication  one  with  another,  each  containuig 
dormitory  and  day  accommodation  for  about  fifty  children,  with  apartments 
for  an  officer  in  charge,  grouped  about  the  necessary  administrative  and 
educational  buildings.  The  cottage-home  system  is  more  modest  in  character 
and  admits  of  greater  diversity  in  design,  comprising  as  it  does  a  sort  of 
complete  village,  the  cottages  being  sometimes  of  different  sizes  and  design, 
and  either  detached,  semi-detached,  or  in  rows.  Each  cottage  is  usually  in 
charge  of  a  foster  mother  or  foster  parents,  the  '  family '  comprising  a  number 

'  So  mucli  is  this  subdivision  of  building  recognised  as  necessary  for  purposes  of  health 
that  in  one  large  Poor-law  school  at  Hanwell  the  main  building,  which  is  upwards  of 
600  ft.  long,  has  recently  been  divided  into  five  distinct  blocks  by  having  gaps  cut 
through  it  at  four  points  in  its  frontage. 

VOL.  I.  Z  Z 


706  HYGIENE 

of  children  varying  from  about  ten  to  as  many  as  thirty,  sometimes  exclu- 
sively of  one  sex  and  occasionally  of  both  sexes,  according  to  the  ages  and 
characters  of  the  children.  The  '  village  '  usually  includes  a  school  building, 
industrial  workshops,  and  such  other  buikhngs  in  the  way  of  infirmary, 
probation  wards,  superintendent's  house,  &c.,  as  the  circumstances  necessitate  ; 
but  these  are  eonnnonly  of  very  modest  pretensions,  as  one  of  the  cottages  in 
a  slightly  modified  form  can  be  made  to  serve  each  or  any  of  these  purposes, 
and  the  need  for  infirmary  accommodation  in  these  villages  is  never  very 
great,  while  in  each  '  home  '  a  small  spare  bedroom  is  generally  provided  in 
which  a  case  of  slight  indisposition  may  be  temporarily  separated  from  the 
other  children  so  as  to  be  more  directly  under  the  observation  of  the  foster 
mother. 

Schools  on  the  family  system,  with  agricultural  labour  as  the  chief 
industrial  training,  have  been  in  operation  on  the  Continent  much  longer  than 
here,  for  Pestalozzi  iiitroduced  into  Switzerland  farm  schools  on  this  plan 
shortly  after  the  middle  of  last  century,'  and  the  reformatory  school  at 
]\Iettray,  similarly  conducted,  has  been  in  existence  for  nearly  fifty  years ; 
but  even  in  the  United  Kingdom  the  system  has  been  in  operation,  both 
under  the  Poor-laws  and  at  charitable  institutions,  a  length  of  time  suffi- 
cient to  warrant  an  opinion  being  formed  regarding  it,  and  in  tlais  particular 
it  seems  to  leave  little  to  be  desired,  especially  as  regards  the  health  of  the 
children. - 

It  would  seem  that  until  within  recent  years  one  of  tlie  chief  hygienic 
defects  in  the  arrangement  of  residential  schools  consisted  in  the  undue  aggre- 
gation of  the  children.  They  occupied  a  huge  buildmg  three  or  more  storeys 
high,  large  numbers  were  placed  together  in  each  dormitory,  the  dormitories 
were  situated  along  both  sides  of  a  corridor  which  had  well-holes  in  its  floor  for 
the  passage  of  light  from  the  roof  of  the  uppermost  one  down  to  the  lowest 
one,  and  the  school  and  day  rooms  in  the  lowest  storey  were  similarly  placed 
and  were  occupied  continuously  by  large  numbers  of  children  ;  and  thus  the 
whole  building  was  arranged  so  as  to  contain  one  atmosphere  uniformly 
vitiated  by  the  exhalations  of  a  vast  number  of  individuals  as  well  as  by  other 
common  means  of  contamination.  These  arrangements  undoubtedly  tend  to 
lower  the  standard  of  health  and  to  foster  any  tendency  to  disease  that  may 
already  exist  in  the  individual  children,  while  they  cannot  fail  to  promote 
the  intercommunication  of  any  complaint  that  may  be  introduced  among  the 
children.  The  remedy  for  this  defective  condition  is  to  be  found  mainly  in 
the  converse  of  the  arrangement.  The  children,  instead  of  being  aggregated, 
must  be  segregated  everywhere.  The  buildings  must  be  subdivided  into 
detached  separate  blocks ;  the  dormitories  must  be  of  more  moderate  size, 
and,  as  well  as  the  school  and  day  rooms,  must  have  as  good  means  of  venti- 
lation as  is  usually  required  in  the  case  of  hospital  wards.  The  school- 
rooms must  afford  increased  area  per  child,  and  inasmuch  as  it  is  said  to 
be  necessary  to  have  considerable  numbers  together  for  purposes  of  teachmg, 
the  occupation  of  the  schoolroom  must  be  limited  to  comparatively  short 
periods  between  complete  evacuation  and  exposure  to  fresh  air  by  open 
windows ;  and  arrangements  should  be  made  for  conducting  a  fair  amount  of 

'  Statistics  of  the  Farm  School  System  oil  the  Continent.  By  Joseph  Fletcher. 
London  :  Stanford  &  Co.,  1878. 

-  For  a  further  account  of  the  system  see  Report  of  Dr.  F.  J.  Moiiat  and  Captain  J.  D. 
Bowly,  R.E.,  on  The  Home  or  Cottage  System  of  Training  and  Educating  the  Children  of 
the  Poor.  London :  Printed  for  the  House  of  Commons,  1878.  Since  the  date  of  that 
report  a  number  of  schools  on  this  system  have  been  built  in  various  Poor-law  unions 
of  England  and  Wales,  notably,  for  Birmingham,  King's  Norton,  Wolverhampton,  Leicester, 
West  Derby,  Shoreditch,  Bethnal  Green,  Kensington  and  Chelsea,  &c. 


THE  DWELLING  IQl 

school  teaching  in  the  open  air,  under  cover  if  necessary,  whenever  the 
weather  will  permit.  For  this  purpose  large  trees  are  excellently  adapted  in 
hot  summer  weather,  and  whenever  such  trees  exist  ahout  a  school  or  on  the 
site  of  an  intended  school  every  effort  should  be  used  to  retain  them. 

The  rules  of  the  Education  Department  as  to  the  planning  and  fitting  up  of 
schools  state  generally  that  '  sanitary  laws  are  here  as  vital  as  in  a  hospital,' 
and,  under  the  head  of  '  Windows,'  the  ordinary  rules  respecting  hospitals 
should  here  be  remembered.  Hence  it  may  be  inferred  that  through- venti- 
lation by  means  of  opposite  external  windows  is  deemed  requisite  in  school- 
rooms erected  under  the  auspices  of  that  department,  as  it  is  in  the  case  of 
schoolrooms  for  pauper  children  erected  under  the  authority  of  the  Local 
•Government  Board ;  but  the  important  question  of  the  number  to  be  assembled 
together  in  any  schoolroom  does  not  appear  to  have  been  dealt  with,  the  first 
point  considered  in  planning  a  school  being  how  '  to  seat  the  children  in  the 
best  manner  for  being  taught,'  and  this  tendency  to  aggregation  of  unlimited 
numbers  has  been  noticed  by  Mr.  Nettleship  when,  in  reference  to  ophthal- 
mia in  a  large  school,  he  observed  that  hardly  any  attempt  seemed  to  have 
been  made  to  treat  the  children  otherwise  than  collectively.  As,  however,  it 
is  admitted  that  the  observance  of  sanitary  laws  is  as  important  in  a  school 
as  in  a  hospital,  it  is  certain  that  children  cannot  be  aggregated  in  a  school- 
room with  impunity  any  more  than  patients  can  be  safely  aggregated  in  a 
sick-ward.  The  length  of  time  the  children  are  kept  in  school  being  only 
a  few  hours  at  a  stretch  may  cause  the  prejudicial  effects  to  be  less  readily 
observed  than  in  the  case  of  the  patients  in  continuous  occupation  of  a  sick- 
ward,  but  that  evil  results  ensue  from  massing  large  numbers  together  in 
schoolrooms  will  be  generally  admitted.  These  evil  results  will  be  increased 
or  diminished  in  intensity,  but  not  wholly  removed,  in  proportion  to  various 
circumstances — e.g.  the  general  health  condition  of  the  children,  the  amount 
of  floor  area  and  cubic  space  allotted  to  each  child  in  the  room,  and  the 
efficiency  of  the  ventilation  and  warming  of  the  room  ;  but  the  question  of 
the  maximum  number  that  may  properly  be  collected  together  in  the  school- 
room— and  in  this  must  be  included  those  classrooms  which  open  out  of  the 
schoolroom  or  are  in  direct  aerial  communication  with  it — must  ere  long 
be  more  generally  considered  in  order  to  promote  the  subdivision  of  the 
children. 

The  amount  of  space  for  each  child  in  a  schoolroom  is  a  detail  which  in 
recent  years  has  received  more  attention  than  formerly ;  for  while  it  was 
usual  to  require  merely  an  average  amount  of  floor  space  for  each  child,  with 
a  specific  height  for  the  room,  it  is  now  customary  to  determine  the  accom- 
modation of  a  schoolroom  by  the  number  of  children  that  can  be  properly  seated 
in  it,  regard  being  had  to  the  kind  of  desk  and  to  the  positions  of  the  doors  and 
fireplaces  ;  and  thus,  in  a  room  otherwise  well  suited  for  the  purpose,  much 
space  may  be  sacrificed,  so  far  as  the  number  of  children  to  be  accommodated 
is  concerned,  owing  to  the  arrangement  of  these  details.  This  lost  space  is 
usually  described  as  '  wasted,'  but  inasmuch  as  it  tends  to  increase  the  other- 
wise very  small  quantity  of  cubic  space  available  for  each  child,  this  term  is 
hardly  a  desirable  one.  The  requirements  of  the  Education  Department 
prescribe  a  width  of  from  18  ft.  to  20  ft.  or  22  ft.  for  a  schoolroom,  and 
state  that  if  the  width  does  not  exceed  20  ft.  groups  of  three  long  desks 
must  be  used,  but  if  the  width  is  22  ft.  dual  desks,  five  rows  deep,  must  be 
used.  It  is  further  stated  that  a  length  of  18  inches  is  to  be  allotted  to  each 
child  on  the  long  desks,  with  gangways  18  inches  wide  between  the  groups, 
and  in  the  case  of  the  dual  desks,  which  are  40  inches  long,  the  gangways 
between  them  need  be  only  16  inches.     The  height  of  the  schoolroom  must 

zz  2 


708  HYGIENE 

be  from  12  ft.  to  14  ft.  These  dimensions  give  an  average  floor  area  of 
rather  over  10  sq.  ft.  to  each  child,  with  cubic  space  of  about  123  ft.  (calculat- 
ing the  height  at  12  ft.)  In  the  case  of  workhouse  schools,  where  the  dormitories 
are  sometimes  placed  above  the  schoolrooms — an  arrangement  which  tends  to 
fix  a  width  of  18  ft.  only  for  the  schoolrooms — the  amount  of  floor  area  and 
cubic  space  per  child  is  slightly  less,  averaging  about  9}  sq.  ft.  and  about 
111  cub.  ft.  of  space  per  child.  In  the  case  of  infants'  schools  the  Education 
Department  are  satisfied  with  a  floor  area  of  only  8  ft.  per  child,  which  gives 
scarcely  100  cub.  ft.  per  head. 

These  capacities  are  obviously  very  small,  and  can  only  be  justified 
on  the  supposition  that  the  warming  and  ventilation  arrangements  are  so 
complete  that  the  air  of  the  room  will  be  constantly  changed  without 
creating  draught  and  without  unduly  affecting  the  temperature  of  the  room, 
whatever  may  be  the  condition  of  the  external  atmosphere.  But  unfor- 
tunately this  is  only  a  supposition,  since  in  actual  practice  it  is  found 
impossible  to  ensure  these  important  conditions,  the  more  so  as  it  is  not 
usual  to  employ  anyone  possessmg  that  interest  in  the  subject  and  tli& 
practical  skill  which  are  indispensable  for  efficiently  regulating  the  warmth 
and  ventilation  at  all  seasons  of  the  year.  The  best  alternative  to  this  in- 
efficient control  of  constant  ventilation  seems  to  be  the  provision  of  a  larger 
amount  of  cubic  space  per  child  without  unduly  increasing  the  usual  height 
for  schoolrooms,  and  it  cannot  be  too  strongly  urged  that  this  should  be 
generally  effected.  Mr.  Charles  E.  Paget,  Medical  Officer  of  Health  at 
Salford,  in  his  '  Handbook  on  Healthy  Schools '  ^  advocates  400  cub.  ft.  of 
space  per  child  as  a  minimum  in  elementary  schoolrooms,  and  800  in  the 
schoolrooms  of  the  great  public  schools.  Where  the  schoolroom  is  of  the 
requisite  size  for  the  whole  number  of  children  attending  school,  and  class 
rooms  are  provided  in  addition,  as  is  prescribed  under  the  Poor-law  require- 
ments of  the  Local  Government  Board,  it  follows  that  a  very  substantial 
addition  to  the  space  per  child  is  afforded  in  the  schoolroom,  since  many  of 
the  childi'en  are  absent  from  that  room  for  considerable  periods  when  attend- 
ing classes  in  other  rooms  or  undergoing  industrial  training,  and  the  remain- 
ing children  get  the  benefit  of  the  additional  space  in  the  schoolroom. 

The  arrangement  of  windows  for  lighting  the  schoolroom  should  be  such 
that  the  light  should  be  admitted  as  much  as  possible  on  the  left-hand  side 
of  the  pupils.  This  is  more  particularly  necessary  in  the  classrooms.  In 
any  case  it  is  important  to  avoid  so  arranging  the  windows  that  a  strong 
light  is  admitted  directly  in  face  of  the  children,  as  this  would  aggravate  any 
tendency  to  weakness  in  the  eyes.  A  strong  light  behind  the  children  is 
objectionable  for  educational  reasons.  From  a  hygienic  point  of  view  there 
is  advantage  in  placing  the  desks  in  a  schoolroom  across  the  room,  so  that 
the  children  should  pit  with  the  windows  on  their  sides,  the  ^\indows  admit- 
ting the  strongest  hght  being  on  their  left-hand  side,  the  other  windows  being 
adapted  mainly  for  purposes  of  ventilation.  The  sills  of  the  windows  may,. 
with  some  advantage,  be  at  a  higher  level  than  is  usually  deemed  desirable 
in  ordinary  day  rooms,  a  height  of  4  ft.  or  4  ft.  6  in.  above  the  floor  being 
a  useful  average  height  for  them  in  schoolrooms.  They  should,  however, 
invariably  extend  up  to  within  a  few  inches  of  the  ceihng  level. 

In  addition  to  the  school  and  class  rooms  the  residential  school  must 
include  those  other  rooms  which  are  necessary  out  of  school  hours  in  order 
that  the  children  may  be  able  to  vacate  the  schoolroom  at  intervals  for 
purposes  of  recreation  when  the  weather  does  not  permit  of  their  being  out 
of  doors,  and  where  they  may  pass  the  long  winter  evenings.     Such  rooms, 

'  Health  Exhibition  Literature,  vol.  i.    London :  William  Clowes  &  Sons,  1884. 


THE  DWELLING  709 

•which  are  usually  termed  day  rooms,  should,  according  to  the  rules  of  the 
Local  Government  Board,  afford  floor  area  of  at  least  10  square  feet  per 
child,  and  be  from  10  to  12  feet  in  height.  This  amount  of  space,  how- 
ever, is  regarded  by  some  authorities  as  very  scanty.  Mr.  C.  E.  Paget  urges 
the  provision  of  space  at  the  rate  of  1,000  cubic  feet  per  child,  renewable 
at  the  rate  of  2,000  feet  per  child  per  hour.  These  rooms  should  be  well 
ventilated  by  windows  opening  into  the  external  air  in  their  opposite  side 
walls,  and  are  best  situated  upon  the  ground  floor,  so  as  to  be  ready  of  access 
"to  the  playgrounds.  Like  the  schoolrooms,  they  should  have  a  solid  floor  of 
wooden  blocks,  and  must  be  capable  of  being  suitably  warmed  in  winter. 
They  ought  not  to  be  used  by  the  children  for  taking  their  meala  in,  but  a 
separate  hall  or  dining-room,  well  ventilated  and  warmed,  is  indispensable 
for  that  purpose.  The  dining-room  must  be  so  arranged,  as  regards  the 
domestic  offices  and  its  means  of  ingress  and  egress,  that  the  food  should 
be  served  to  the  children  in  a  hot  and  palatable  condition.  It  is  a  most 
unfortunate  thing  for  the  children  if  the  food  intended  to  be  eaten  hot  is 
allowed  to  get  chilled  before  it  is  served  to  them  or  before  they  can  reach 
their  seats  and  commence  their  meals.  Such  conditions  are  apt  to  lead  to 
the  food  being  wasted  instead  of  being  consumed  by  the  children,  and  it  may 
here  be  pointed  out  that  the  meals  at  boarding-schools  are  sometimes 
arranged  at  such  considerable  intervals  that  the  children  cannot  be  deprived 
•of  any  portion  of  the  food  served  to  them  without  disadvantage. 

In  residential  schools  the  dormitories  are  usually  in  the  one  and  two  pair 
storeys,  and  the  arrangement  generally  ought  to  follow  that  prescribed  for 
wards  for  the  sick,  with  such  modifications  only  as  may  be  desirable  under 
the  different  circumstances  for  which  the  dormitories  are  to  be  used.  The 
usual  width  in  the  case  of  Poor-law  schools  is  18  feet,  each  bed,  according 
to  the  requirements  of  the  Local  Government  Board,  havuag  a  minimum  of 
3  feet  9  inches  of  wall  space,  36  square  feet  of  floor  space,  and  360  cubic  feet 
•of  air  space.  If  the  dormitories  are  15  feet  wide  the  wall  space  has  to 
be  increased  to  4  feet.  These  amounts  of  space  are  certainly  the  least  that 
could  be  allowed  with  propriety,  but  they  are  in  excess  of  what  was 
formerly  considered  requisite  when,  moreover,  the  children  were  commonly 
permitted  to  be  placed  two  in  a  bed — an  arrangement  which  is  now 
prohibited.  Dr.  Clement  Dukes,  in  discussing  the  subject  of  school 
•dormitories  at  a  conference  at  the  Health  Exhibition  in  1884,^  points  out 
that  a  plentiful  supply  of  sleep  in  dormitories  affording  ample  and  pure  air, 
is  as  important  to  the  young  and  growing  as  a  plentiful  supply  of  food,  and 
he  believes  that,  notwithstanding  this,  some  50  per  cent,  of  the  dormitories 
■in  the  boarding-schools  of  Great  Britain  '  would  be  found  to  be  as  bad  as 
they  could  possibly  be,  and  40  per  cent,  just  passable,  but  nothing  Mke  what 
they  should  be.'  He  further  points  out  as  '  an  incontrovertible  fact '  that  in 
many  of  our  schools  there  is  less  than  300  cubic  feet  of  space  per  head  in 
the  dormitories. 

In  France,  among  the  rules  laid  down  for  the  construction  and  furnish- 
ing of  normal  schools  by  the  Covimission  des  Bdtiments  Scholaires,  it  is 
•prescribed  ^  that  the  dormitories  are  never  to  hold  more  than  thirty  beds,  are 
to  have  windows  in  their  opposite  side  walls,  are  to  be  at  least  4  metres  high 
and  7^  metres  wide,  that  the  space  between  the  beds  shall  be  at  least  a  metre 
wide,  and  that  as  the  beds  are  80  centimetres  wide  each  bed  shall  have  a  wall 
space  of  1  metre  80  centimetres,  and  floor  area  of  about  6|  square  metres  and 

'  Health  Exhibition  Literature,  vol.  si.    London  :  William  Clowes  &  Sons,  1884. 
2  L' Etude  et  les  Progres  de  VHygiene  en  France  de  1878  d  1882.    Paris  :  G.  Masson, 
•Miteur,  libraire  de  I'Academie  de  Medecine,  1882. 


710  HYGIEXE 

about  27  metres  of  cubic  space.  The  rules  go  on  to  prescribe  that,  where 
movable  curtains  to  separate  the  beds  are  not  adopted,  the  Commission 
recommend  cubicles  (cabines)  at   least  2   metres   75  centimetres  deep  by 

1  metre  80  centimetres  wide,  with  a  central  passage  1  metre  50  centimetres 
wide.  If  preferred,  the  cubicles  may  be  placed  in  two  rows  against  a  central 
longitudinal  pai-tition  with  a  passage  a  metre  wide  along  each  side  of  the 
dormitory.     The  partitions  separating  the  cubicles  are  to  be  not  more  than 

2  metres  high,  and  raised  at  least  20  centimetres  off  the  floor,  and  each 
cubicle  is  to  be  furnished  with  merely  a  bed,  a  stool,  and  a  clothes-box.  It 
is  stated,  however,  that  the  system  of  cubicles  is  not  generally  adopted. 
"Whether  the  cubicle  system  or  the  open  dormitory  is  adopted,  there  is, 
according  to  these  rules,  a  very  large  amount  of  space  available  for  each 
pupil,  and,  as  the  cubicles  are  not  furnished  for  use  otherwise  than  for 
sleeping,  they  can  be  thoroughly  aired  during  the  day.  It  is  perhaps 
hardly  to  be  expected  that  so  much  space  can  be  generally  given  to  each  boy 
or  girl  in  school  dormitories  of  institutions  and  inexpensive  schools  in  this 
country,  but  as  a  general  rule  the  amount  of  space  afforded  is  very  in- 
adequate. Both  Dr.  Dukes  and  Mr.  C.  E.  Paget  advocate  for  our  climate  800 
cubic  feet  of  space,  with  some  70  square  feet  of  floor  area  for  each  child, 
it  being  urged  that  with  less  space  it  is  often  impracticable  to  ensure  efficient 
ventilation  -v^ithout  draught.  Moreover,  the  beds  must  be  kept  at  a  sufficient 
distance  apart  in  order  to  diminish  the  risk  of  any  complaint  or  constitu- 
tional disorder  being  communicated  from  the  occupier  of  one  bed  to  that  of 
the  next  bed.  Dr.  Dukes  further  expresses  the  opinion  that  from  ten  to 
sixteen  beds  in  each  dormitory  is  an  appropriate  number. 

Upon  the  question  of  the  advantages  and  disadvantages  of  the  cubicle 
system  opinions  seem  to  differ,  there  being  perhaps  as  many  and  as  powerful 
advocates  for  the  one  system  as  for  the  other.  That  cubicles,  except  under 
very  good  general  administration,  are  capable  of  abuse  and  may  tend  to 
prejudice  the  moral  as  well  as  the  health  condition  of  a  school  can  hardly 
be  doubted.  Dr.  Dukes  regards  them  with  much  disfavour,  and  Dr.  Alder 
Smith  considers  them  '  an  abomination  in  every  way  ; '  but  on  the  other  hand 
Mr.  C.  E.  Paget,  in  his  paper  on  Healthy  Schools,  already  referred  to,  records 
his  opinion  as  decidedly  favourable  to  the  cubicle  system  in  well-managed 
schools.  All  authorities,  however,  agree  in  the  necessity,  from  a  health  point 
of  view,  for  the  absolute  prohibition  of  the  use  of  the  cubicles  for  purposes  of 
study.  In  fact,  no  kind  of  occupation  should  be  allowed  in  the  dormitories 
or  cubicles  during  the  day.  One  important  advantage  of  the  cubicle  over 
the  open  dormitory,  however,  is  that  it  practically  necessitates  the  pro- 
vision of  a  greater  amount  of  cubic  space  than  where  the  beds  are  placed 
along  the  sides  of  an  open  dormitory,  and  where  they  may  consequently  be  put 
closer  together  if  the  number  of  children  to  be  accommodated  renders  it 
necessary.  "Where  the  beds  have  each  only  a  very  small  amount  of  wall  space 
it  is  practically  impossible  to  avoid  placing  some  of  them  immediately  under 
the  windows,  an  arrangement  that  should  always  be  avoided  as  far  as  possible. 

The  flooring  of  dormitories  for  children  should  be  of  well-seasoned  board- 
ing, properly  grooved  and  tongued,  and  whether  stained  or  not  should  be 
polished  with  bees'-wax  or  paraffin.  This  is  far  better  than  that  frequent 
washing  and  scrubbing  which  is  so  often  effected  in  many  schools,  and  which 
m  damp  weather  is  so  difficult  to  get  dry  by  the  children's  bedtime. 

The  question  as  to  the  best  arrangements  for  purposes  of  ablution  in  the 
residential  school  is  one  which  requires  the  most  careful  consideration,  since 
the  cleanhness  of  the  skin  is  of  such  importance  to  the  health  conditions  of 
the  children.     As  regards  lavatories  it  has  been  alleged,  with  much  apparent 


THE  DWELLING  111 

reason,  that  one  of  the  means  by  which  ophthalmia  has  been  spread  amongst 
the  children  in  pauper  schools  has  been  not  only  by  the  use  in  common  by 
several  children  of  the  same  towel,  but  also  by  the  wash-hand  basins  being 
imperfectly  rinsed  after  use,  so  that  secretions  discharged  from  the  diseased 
eyes  of  one  child  have  been  left  in  the  basin,  and  been  allowed  to  mingle 
with  the  clean  water  used  by  the  next  child  washing  at  the  same  basin. 
Although  this  means  of  communication  of  disease  has  not  been  actually 
proved,  its  probability  affords  a  strong  a  priori  reason  for  guarding  against 
such  a  possibility,  and  consequently  not  only  have  round  roller  towels  been 
practically  abolished  in  most  Poor-law  schools,  but  the  use  of  ordmary  wash- 
ing basins  in  them,  especially  the  larger  schools,  has  been  done  away  with, 
and  an  arrangement  substituted  by  which  each  child  washes  at  a  running  jet 
or  spray  of  water,  so  that  it  is  practically  impossible  for  the  same  water  to  be 
used  by  more  than  one  child.  The  water,  which  can  be  delivered  at  any 
required  temperature,  falls  into  surface  channels  on  the  floor  behind  slate 
slabs  to  protect  the  children  from  splashing,  and  experience  has  shown  that 
the  quantity  of  water  consumed  under  this  system  can  be  so  regulated  as 
scarcely,  if  at  all,  to  exceed  that  ordinarily  used  in  wash-hand  basins,  while 
the  children  are  able  to  thoroughly  wash  the  whole  upper  part  of  their  bodies. 
The  system  had  been  in  use  for  many  years  at  the  Eoyal  Military  Asylum  at 
Chelsea  before  it  was  adopted,  some  fifteen  years  ago,  in  certain  Poor-law 
schools,  but  the  details  of  arrangement  have  since  been  improved  in  various 
ways.  The  necessity  for  supplying  hot  water  to  children's  lavatories  is  some- 
times regarded  as  a  needless  expense,  it  being  contended  that  such  a  luxury 
is  not  met  with  in  the  ordinary  dwelling  of  other  than  the  well-to-do  classes. 
But  it  is  at  least  necessary  in  the  case  of  children  of  the  low  condition  of 
vigour  and  vitality  usually  met  with  among  the  very  poor,  and  accordingly 
in  most  pauper  schools  it  has  been  found  desirable  to  require  an  adequate 
supply  both  of  hot  and  cold  water,  and  it  is  recommended  that  the  lavatory 
arrangements  should  be  such  as  will  admit  of  each  child  washing  the  hands, 
face,  and  upper  half  of  the  body  at  least  twice  daily.  For  this  purpose 
it  is  requisite  to  provide  jets,  or  basins  where  the  running-jet  system 
is  not  adopted,  in  the  proportion  of  fifteen  jets  or  basins  to  every  hundred 
children. 

With  regard  to  the  important  question  of  baths  for  the  children  it  is  much 
to  be  wished  that  the  practice  of  daily  bathing  for  every  boy  or  girl  could  be 
carried  out  in  all  schools.  This,  even  in  some  of  our  best  public  schools,  is 
regarded  as  impracticable,  but  the  daily  cleansing  of  the  skin  by  means  of 
cold  bathing  and  friction  has  so  many  hygienic  advantages  that  it  is  desirable 
to  aim  at  this  practice  as  nearly  as  the  circumstances  permit.  For  very 
young  children,  however,  and  children  of  the  poor  condition  already  referred 
to,  the  use  of  cold  water  at  all  seasons  would  hardly  be  right,  and  therefore, 
for  those  children  at  any  rate  tepid  or  warm  baths  should  be  provided.  The 
regulations  of  the  Local  Government  Board  prescribe  that  the  bathing 
arrangements  in  Poor-law  schools  should  admit  of  every  child  being  bathed 
at  least  once  a  week  in  winter  and  twice  a  week  in  summer,  and  certainly  m 
other  residential  schools  the  facilities  for  bathing  ought  not  to  be  less. 
Glazed  fireclay  baths,  such  as  are  made  at  Stourbridge,  are  among  the  best 
adapted  for  the  purpose,  as  they  are  very  strong,  the  surface  is  durable  and 
can  be  kept  clean  without  difficulty,  and  they  do  not  require  casing  in.  They 
absorb  a  certain  quantity  of  heat  from  the  water,  but  where  they  are  used  by 
a  number  of  successive  bathers,  as  is  the  case  at  schools,  being  of  course 
emptied  and  recharged  repeatedly,  the  loss  of  heat  which  occurs  at  first 
is  not  of  much  consequence.     It  is  a 'wise  precaution,  in  the  case  of  baths  to 


712  HYGIENE 

be  used  by  children,  to  have  a  movable  key,  or  spanner,  to  the  hot-water  tap, 
to  be  kept  in  chai-ge  of  the  attendant,  as  otherwise  accidents  by  scalding 
may  occur.  In  all  schools,  whether  for  boys  or  for  girls,  the  children  ought 
to  be  taught  to  swim.  At  most  schools  some  provision  is  now  generally 
made  to  effect  this  most  desirable  object.  Where  the  school  is  near  the  sea 
or  on  a  suitable  river,  swimming  therein  is  commonly  practised  in  the  summer 
months  AA-ith  great  advantage  to  the  children.  During  the  winter,  the 
children  ought  to  have  the  opportunity  of  going  to  a  public  swimming  bath, 
where  the  Avater  is  kept  at  a  suitable  temperature — say  about  70°  Fahr. — 
and  this  is  done  by  arrangement  in  the  case  of  many  public  and  private 
schools  in  the  provinces.  But  at  numerous  Poor-law  schools  and  other 
similar  institutions,  swimming  baths  have  been  specially  constructed  for  the 
use  of  the  children  witli  excellent  results.  One  good  bath,  arranged  so  as  to 
be  available  by  the  children  of  either  sex,  is  far  better  than  a  separate  bath 
of  smaller  size  for  each  sex.^  Mr.  Paget,  however,  urges  that  in  the  interest 
of  health,  even  where  swimming  baths  are  occasionally  resorted  to,  the 
practice  of  daily  cold-water  sponging  should  still  be  encouraged  as  much  as 
possible,  and  he  adds  that  as  physical  health  depends  largely  upon  its  being 
carried  out,  no  school  should  be  called  a  healthy  school  which  does  not 
provide  some  regular  means  for  its  accomplishment. 

The  next  important  point  in  connection  with  schools  of  the  type  under 
consideration  is  that  of  closet  accommodation,  and  with  respect  to  this  it  may 
at  once  be  said  that  while  the  closets  for  night  use  must  of  necessity  be 
attached  to  the  building  and  in  near  proximity  to  the  dormitories,  those  for 
general  and  day  use  ought  to  be  wholly  detached  and  out  of  doors.  In  the  in- 
terests of  purity  of  air  within  the  building,  the  closets  attached  to  the  building 
must  be  arranged  in  the  same  way  as  is  now  universally  required  in  the  case 
of  the  closets  of  hospitals — i.e.  they  must  be  placed  in  projections  from  the 
building,  provided  with  opposite  external  windows  for  the  purpose  of  cross- 
ventilation,  and  must  further  be  separated  from  the  interior  of  the  building 
by  an  intervening  lobby,  itself  having  independent  cross-ventilation.  What- 
ever form  of  closet  is  adopted,  whether  on  one  of  the  systems  of  dry-earth  or 
on  the  water-closet  system,  it  should  be  regarded  as  indispensable  that  this 
arrangement  should  be  carried  out.  The  requisite  amount  of  accommodation 
in  connection  with  the  dormitories  is  never  large,  since,  where  the  children 
are  in  good  health,  they  are  not  often  resorted  to  at  night,  but  one  closet  ought 
at  least  to  be  readily  accessible  from  each  dormitory.  The  same  projection 
may  usefully  contain  the  slop  sink  and  housemaid's  sink  where  the  chamber 
utensils  are  emptied  and  thoroughly  cleansed,  for  the  slop  sink,  which  receives 
a  quantity  of  excreta,  ought  to  be  treated  in  the  same  manner,  as  regards  its 
position  and  arrangement,  as  the  water-closet.  It  is  very  desirable  that  the 
use  of  chamber  utensils  in  dormitories  should  be  abolished  as  much  as  possible, 
as  the  retention  of  them  involves  the  exposure  of  a  considerable  surface,  in 
the  aggregate,  of  urine,  which  must  tend,  by   evaporation,  to  vitiate  the 

'  Mr.  Ernest  Turner,  F.R.I.B.A.,  in  his  Eeport  to  the  Social  Economy  Committee  of 
the  Paris  International  Exhibition  1889  (British  Section)  on  Public  Baths  and  Wash- 
houses,  refers  to  a  new  system  of  heating  the  water  at  the  baths  of  the  Boyal  Military 
Academy  at  Woolwich,  for  which  it  is  claimed  that  the  whole  of  the  heat  generated  is 
used,  and  a  uniform  temperature  ensured.  With  this,  he  adds,  may  be  combined  a  system 
of  continuous  forced  circulation  of  the  water  through  a  purifying  and  aerating  apparatus, 
by  means  of  which  the  purity  of  the  water  may  be  maintained  for  a  considerable  period 
without  great  loss  of  heat.  The  cost  of  heating  is  thus  reduced  to  a  minimum,  as  cold 
water  need  not  be  introduced  in  the  baths  so  frequently,  and  the  cost  of  raising  its  tem- 
perature is  avoided.  The  system  is  the  invention  of  Mr.  Charles  H.  Eosher,  C.E.,  who  has 
been  assisted  in  reference  to  the  purification  of  the  water  by  Mr.  A.  H.  Hobson,  F.R.M.S.,  F.C.S. 


THE  DWELLING 


ri3 


■atmospliere  of  tlie  dormitory.  In  some  schools  for  boys,  nririals  have  Ijeen 
provided  in  suitable  projections  from  the  staircases  and  the  children  en- 
couraged to  use  them  night  and  morning,  thus  admitting  of  a  great  reduction 
in  the  number  of  chamber  utensils  in  the  dormitories. 

For  day  use,  out-door  closets  should  be  provided,  and  as  these  would 
iDe  the  closets  generally  used  by  the  children  they  should  not  be  unduly 
remote  from  the  day  and  school  rooms,  nor  should  they  be  so  placed  that,  in 
going  to  and  from  them,  the  children  would  be  much  exposed  to  the  weather. 
It  is  indispensable  that  they  should  be  well  lighted  after  dark.  This  is 
requisite  not  only  on  the  score  of  cleanliness  and  morals,  but  in  order  that 
the  children  may  not  shrink  from  going  to  them  during  the  winter  evenings. 
The  number  of  closets  needed  for  a  given  number  of  children  is  another 
point  that  calls  for  attention,  since,  if  the  number  of  closets  is  scanty,  the 
children  may  be  led  to  neglect  or  to  be  irregular  in  the  use  of  them,  and 
every  effort  should  be  made,  in  the  interest  of  their  health,  to  facilitate  and 
encourage  regularity  in  this  respect.  The  Education  Department  prescribe 
the  rate  of  closet  accommodation  as  follows  : 


Number  of  children 

Number  of  Closets 

For  Girls 

Por  Boys 

Under  50 

3 

2 

„      70 

4 

2 

„     100 

5 

3 

„     150 

6 

3 

„     200 

7 

4 

„    300 

8 

5 

and  urinals  in 
proportion 

But  inasmuch  as  these  numbers  relate  to  day  schools  only,  where  it  may  be 
expected  that  a  large  majority  of  the  children  will  have  obeyed  the  daily  call 
of  nature  before  leaving  home,  it  follows  that  a  considerably  higher  rate 
of  closet  accommodation  is  requisite  at  the  residential  school.  The  Local 
Government  Board  have  prescribed,  for  Poor-law  schools,  a  rate  of  10  closets 
per  cent,  for  boys  and  15  per  cent,  for  girls — urinals  being  requisite  in 
addition  for  the  boys,  and  this  would  seem  a  proportion  that  may  fairly  be 
applied  to  residential  schools  generally. 

The  precise  kind  of  closet  best  adapted  for  children  will  depend  much 
upon  the  locality.  If  the  institution  is  so  situated  that  an  ample  supply 
of  water  and  a  proper  system  of  sewers  are  available  there  can  hardly 
be  any  question  as  to  the  advisability  of  adopting  some  kind  of  water- 
closet  ;  on  the  other  hand,  where  water  supply  and  sewers  are  not  avail- 
able, the  dry-earth  system  is  undoubtedly  the  best.  The  privy  in  which 
the  excreta  are  covered  or  mingled  with  coal-ash  is  much  used  in 
certain  parts  of  the  country,  but  in  schools,  where  the  consumption  of 
coal  and  production  of  ashes  is  necessarily  very  small  in  proportion  to  the 
number  of  children  using  the  privies,  it  is  scarcely  ever  found  to  be  a 
satisfactory  system,  the  contents  of  the  receptacle  beneath  the  privy  seat 
being  generally  in  a  wet  and  offensive  condition.  In  country  districts  where 
the  dry-earth  system  is  in  use,  it  is  generally  possible  to  obtain  an  ample 
quantity  of  suitable  garden  mould  containing  organic  matter;  with  reason- 
able attention  on  the  part  either  of  those  using  the  closets,  or  better 
■still  on  the  part  of  the  school  officers,  who  should  take  care  that  the  proper 
quantity  of  properly    sifted   dry  earth   is   thrown .  into  the   receptacle   at 


7U  HYGIENE 

certain  regular  intervals  every  day,  the  system  is  an  admirable  one,  and  the- 
contents  of  the  receptacle  may  be  retained  undisturbed  for  a  much  longer 
period  than  is  permissible  in  the  case  of  a  coal-ash  privy.  But  whenever 
adopted  it  cannot  be  too  strongly  insisted  upon  that  the  necessary  supervision, 
attendance,  and  appliances  for  keeping  the  closets  free  from  nuisance  will  be 
regularly  and  duly  supplied,  otherwise  the  system  cannot  be  expected  to  prove 
satisfactory. 

As  regards  the  details  of  construction,  it  is  necessary  to  keep  the 
receptacle,  if  fixed,  wholly  above  the  level  of  the  ground  adjacent,  in  order 
to  preclude  the  possibility  of  surface  water  finding  its  way  into  it  and 
rendering  the  contents  unduly  wet ;  for  it  is  of  the  utmost  importance  that 
the  contents  of  the  receptacle  should  be  kept  as  dry  as  possible.  Where 
the  receptacle  is  movable,  as  in  the  case  of  tubs  or  pails,  the  regularity  of 
service  and  attention  is  not  less  important  than  in  the  case  of  the  fixed  recep- 
tacle, but  greater  frc([uency  of  removal  becomes  necessary,  as  the  receptacle, 
being  small  for  facility  of  manipulation,  is  sooner  filled.  Where  water  and 
sewers  are  available,  the  best  kind  of  closet  for  outdoor  use  is  that  known  as 
the  trough  closet,  with  a  periodical  automatic  flush.  These  closets,  when  the 
trough  is  made  of  glazed  stoneware  of  a  light  colour,  can  hardly  be  surpassed 
for  cleanliness  and  suitability. 

Every  residential  school  ought  to  have  a  complete  laundry  of  its  own,  so 
as  to  avoid  the  necessity  for  sending  the  soiled  linen  away  to  be  dealt  with, 
possibly  in  places  that  are  already  infected,  or  in  which  there  are  infected 
persons  or  things.  The  laundry  building  should  be  at  a  distance  from  the 
occupied  school  buildings,  and  ought  to  have  a  good  drying  ground,  where 
the  linen  could  be  exposed  to  light  and  air  whenever  the  weather  permits. 
It  ought  also  to  have  an  efficient  drying  ap]Daratus  for  use  when  the  weather 
does  not  admit  of  the  wet  linen  being  dried  out  of  doors  ;  likewise  a  well- 
ventilated  room  for  airing  the  finished  linen  after  leaving  the  ironing  and 
manghng  room.  Near  the  laundry  there  should  be  a  good  dismfecting 
chamber.  Such  a  provision  is  an  excellent  precaution  against  the  introduc- 
tion of  clothing  and  other  articles  suspected  of  infection.  The  best  appa- 
ratus for  the  purpose  is  that  in  which  the  articles  to  be  disinfected  can. 
be  submitted  to  steam  at  high  pressure  so  as  to  penetrate  to  the  innermost 
parts  of  the  article.  There  are  two  or  three  good  kinds  of  disinfecting 
apparatus,  but  a  detailed  account  of  the  efficiency  of  several  kinds  will  be 
found  in  the  official  report  (1885)  on  the  subject  by  Dr.  H.  Franklin 
Parsons,  one  of  the  IMedical  Inspectors  of  the  Local  Government  Board. 

In  separate  Poor-law  schools  it  is  usual  to  include  among  the  buildings  a 
block  of  probationary  wards,  where  children  on  their  first  arrival  can  be  kept 
in  some  sort  of  quarantine  until  it  has  been  ascertained  that  they  are  free 
from  disease.  The  necessity  for  such  wards  has  been  demonstrated  over  and 
over  again  in  the  case  of  many  complaints  common  to  childhood  and  which 
are  not  always  obvious  in  their  early  stages  ;  but  especially  have  such  wards 
been  found  necessary  in  regard  to  ophthalmia.  This  subject  is,  however,, 
referred  to  later  in  connection  with  school  sanatoria. 

WORKHOUSES 

The  English  workhouse  is  an  institution  which,  since  it  first  became  a 
necessity,  has  undergone  at  least  as  much  change  in  arrangement,  from '  a 
health  point  of  view,  as  have  hospitals  and  prisons.  The  importance  of  these 
Poor-law  institutions  is  alone  a  sufficient  reason  for  giving  the  subject  special 
consideration  ;  for  in  England  and  Wales  there  are  some  650  unions  and 


THE  DWELLING  715 

Poor-law  authorities,  each  possessing  one  workhouse,  and  many  of  them 
having  several  workhouses  of  one  sort  or  another.  In  these  are  housed 
about  200,000 '  paupers,  and  the  amount  annually  expended  upon  these 
buildings  (irrespective  of  repairs),  in  altering  and  enlarging  them  and  in 
erecting  new  ones,  is  about  500,000/.  The  old  parish  poorhouse,  in  whicli, 
under  the  direction  of  the  overseers,  the  poor  were  formerly  relieved,  was 
bad  in  every  conceivable  way,  and  the  whole  system  of  the  relief  of  the 
poor  became  so  scandalous  that,  in  1834,  Parliament  passed  the  Poor-law 
Amendment  Act,  which,  with  certain  further  amending  Acts,  has  been  in 
operation  ever  since.  Under  that  Act  unions  of  parishes  were  formed  and 
Boards  of  Guardians  of  the  Poor  were  constituted ;  workhouses  under  respon- 
sible paid  officers  were  provided,  and  the  arrangements  for  the  relief  of  the. 
destitute  poor  were  made  uniform  for  the  whole  of  the  country.  With  the 
scanty  knowledge  that  existed  at  that  time  in  regard  to  all  matters  concern- 
ing health,  it  is  not  surprising  to  find  that  these  early  workhouses  were 
exceedingly  defective  in  their  sanitary  arrangements. 

In  a  recent  publication ^  upon  the  subject,  some  typical  plans  of  the  work- 
houses as  recommended  by  the  first  Poor-law  Commissioners  are  given,  from 
which  it  will  be  seen  that  in  one  instance  a  workhouse  for  500  inmates,  upon 
a  square  site  of  one  acre  of  land,  is  arranged  so  that  the  various  wards  are 
placed  against  the  four  boundary  walls  in  such  a  way  as  to  have  no  other 
ventilation  than  is  derivable  from  the  windows  and  doors  on  the  inner  side 
next  the  courtyard,  and  so  that  each  inmate  would  have  an  average  of  only 
131  cubic  feet  of  space.  In  another  plan,  also  for  a  workhouse  for  500 
inmates  of  all  classes  in  the  one  building,  the  various  wards  certainly  have 
means  of  through  ventilation,  but  the  inmates  were  in  some  cases  placed  in 
beds  tier  above  tier,  and  in  others  two  in  a  bed,  while  the  amount  of  cubic 
space  for  the  sick  was  scarcely  300  feet,  and  for  those  who  were  not  sick  only 
half  that  amount,  and  the  closet  arrangements  within  the  building  were,  as 
may  be  expected,  very  defective.  What  the  precise  results  of  these  conditions 
were  it  is  difficult  now  to  ascertain,  but  while  it  is  probable  that  much  sick- 
ness that  we  now  know  to  be  preventable  was  caused,  and  that  an  excessive 
mortality  prevailed,  it  is  obvious  that  the  arrangements  generally  for  the 
treatment  of  the  sick  were  extremely  unsatisfactory. 

Some  improvement  took  place  in  the  later  arrangements,  but  they 
were  still  very  defective,  and  so  serious  had  these  conditions  become 
towards  1864,  that  in  the  following  year  the  proprietors  of  the  Lancet 
newspaper  started  a  commission  of  their  own  to  inspect  and  report  on 
the  general  state  of  the  Metropolitan  Workhouse  Infirmaries,  and  in  an 
introduction  to  the  reports  so  made  the  Lancet  said  :  '  The  State  hospitals 
are  in  workhouse  wards.  They  are  closed  against  observation  ;  they  pay 
no  heed  to  public  opinion;  they  pay  no  toll  to  science.  They  con- 
travene the  rules  of  hygiene ;  they  are  under  the  government  of  men  pro- 
foundly ignorant  of  hospital  rules.'  The  reports  which  appeared  in  the 
columns  of  that  newspaper  at  intervals  from  the  middle  of  1865  to  the  early 
part  of  1866  led  to  the  appointment  of  a  special  official  inspection  of  the 
workhouses  by  a  medical  inspector  (Dr.  Edward  Smith,  F.E.S.)  and  a  lay 
inspector  (Mr.  Henry  B.  Farnall,  C.B.),  whose  joint  report  was  duly  presented 
to  Parliament.  About  the  same  time  the  Poor-law  Board  appointed  a  com- 
mittee to  inquire  into,  and  report  upon,  the  amount  of  cubic  space  that  ought 
to  be  provided  for  the  several  classes  of  workhouse  inmates,  and  one  of  the 

•  In  1888. 

2  Knight's  Guide  to  the  Arrangement  and  Construction  of  Workhouse  Buildings, 
London  :  Knight  &  Co.,  1889. 


716  HYGIENE 

results  of  tlie  agitation  that  had  taken  place  was  the  passing  of  Mr.  Gathorne 
Hardy's  Act  for  amending  the  laws  relating  to  the  relief  of  the  poor  in  the 
metropolis,  an  Act  which  constituted  the  Metropolitan  Asylums  Board  and 
pro^^ded  for  the  erection  of  separate  hospitals  and  asylums  for  the  reception 
of  the  harmless  imbeciles  who  had  previously  occupied  so  much  space  and 
caused  so  much  trouble  in  the  workhouses,  and  also  of  paupers  suffering 
from  any  of  the  dangerous  infectious  fevers. 

Public  attention  all  this  time  was  being  directed  towards  sanitary 
matters  generally.  The  Royal  Commission  upon  Barracks  and  Hospitals 
had  reported ; .  the  Herbert  Hospital  at  Woolwich  and  the  Chorlton  Union 
Hospital  had  been  erected  on  the  pavilion  system ;  and  much  activity 
began  to  prevail  in  the  improvement  of  workhouses  generally  through- 
out the  country.  The  Poor-law  Board  in  1868  issued  a  set  of  printed 
rules  entitled  '  Points  to  be  attended  to  in  the  Construction  of  Work- 
house Buildings,'  ^  in  which  the  amount  of  space  prescribed  for  each  inmate 
in  the  several  classes  was  fixed  generally  in  accordance  with  the  recommenda- 
tions of  the  Cubic  Space  Committee.  Separate  infirmaries,  independent  of 
the  workhouse  of  the  unions  to  which  they  belonged,  were  erected  in  many 
of  the  larger  unions  and  parishes,  and  were  placed  under  the  superintendence 
of  competent  medical  men  instead  of  as  previously  the  medical  staff  being 
subordmate  to  the  master  of  the  workhouse.  Separate  schools  were  provided 
in  the  suburbs  for  the  metropolitan  pauper  children,  and  likewise  in  connec- 
tion with  some  of  the  large  pro^'incial  unions.  It  will  thus  be  seen  that, 
while  in  the  early  workhouses  the  common  arrangement  was  to  place  all 
the  inmates,  whatever  their  number  and  condition,  in  one  huge  building, 
under  one  roof,  it  is  now  the  practice  to  provide  separate  buildings  at  least 
for  the  inmates  in  health  and  for  the  sick  ;  while  in  the  case  of  workhouses 
for  more  than  a  certain  number  of  inmates,  a  separate  building  is  usually 
provided  for  the  children,  unless  they  are  wholly  removed  from  the  workhouse 
to  some  distinct  and  separate  school.  The  regulations  and  requirements  of 
the  Local  Government  Board  are  very  definite  as  to  this  subdivision  of 
building,  special  stress  being  laid  upon  the  necessity  for  avoiding  the  aggre- 
gation of  large  numbers  of  inmates  in  any  single  block.  This  important 
requirement  is  to  some  extent  met  by  the  equally  important  requirements, 
on  administrative  grounds,  for  the  subdivision  of  classes,  and  accordingly  a 
complete  workhouse  for  a  large  union  will  ordinarily  comprise  the  following 
distinct  buildings  : — 

(a)  Entrance  building,  including  probation  wards. 

(b)  Tramp  wards. 

(c)  Main  building  for  aged  and  able-bodied  inmates  in  health. 

(d)  Imbecile  wards. 

(e)  Children. 
(/)  Infirmary. 

(g)  Isolation  sick  wards. 

But  where  the  number  of  indoor  poor  is  very  large,  some  of  these  buildings 
take  the  form  of  distinct  institutions.  This  is  specially  the  case  in  the 
Metropohtan  Poor-law  district,  where  the  children  are  provided  for  wholly  in 
suburban  schools,  the  harmless  imbeciles  in  suburban  asylums,  and  the  in- 
fectious cases  in  special  fever  and  small-pox  hospitals. 

The  minimum  amount  of  space  prescribed  for  each  pauper  in  the  dormi- 
tories of  the  several  buildings  above  referred  to  is  as  follows  : 

'  Revised  and  reissued  in  1891. 


THE  DWELLING 


in 


Wall  space 
per  bed 


Floor  space 


Cubic  space 


Casual  pauper,  tramp  or  vagrant  wards 

Probation  or  receiving  wards 

Able-bodied  and  aged  . 

Very  infirm  (bed-ridden) 

Women  with  infants     . 

Imbeciles      .... 

Children       .... 

Ordinary  sick  and  syphilitic 

Lying-in  cases 

Offensive  cases 

Sick  children 

In  isolation  wards 


Lineal  feet 
3 

4 
5 
5 
5 
3'  9"  to  4 
6 


5  to  6 
12 


Square  feet 
27 
40 
36 
50 
50 
50 
36 
60 
80 
80 
60 
144 


In  addition  to  the  above,  day-room  space  is  requisite  for  certain  classes, 
such  as  the  casual  pauper,  who  may  be  detained  for  a  short  period  and 
whose  sleeping  accommodation  may  be  in  the  form  of  a  separate  room  or 
cell  having  a  floor  area  of  86  feet  and  360  cubic  feet  of  space  ;  also  for  the 
adult  in  health  at  the  rate  of  15  square  feet  of  floor- space ;  for  the  imbecile 
at  the  rate  of  20  square  feet  cf  area,  and  for  children  10  square  feet  in  addi- 
tion to  their  school  and  class  rooms  and  work  rooms.    For  the  sick,  the  re- 


UNION     WORKHOUSE 

GATE5HE/\D   or*  TTNE" 


Fig.  130. 

quisite  day-room  space  is  to  be  calculated  upon  the  supposition  that  haK  the 
patients  are  able  to  leave  their  sleeping-ward  for  various  periods  during  the 
day,  and  for  each  of  such  patients  the  day-room  should  afford  20  square 
feet  of  space.  It  is  right  to  observe  that  the  prescribed  amounts  of  space,  espe- 
cially in  the  sleeping  wards,  are  generally  the  smallest  that  can  properly  be  re- 
garded as  sufficient,  and,  indeed,  they  are  only  so  prescribed  on  the  supposition. 


718  HYGIENE 

that  the  arrangements  throughout  for  ventilation  and  warming  are  complete 
and  efficient.  As  minimum  qiumtities  of  space,  they  are  in  practice  often  ex- 
ceeded, aswould  be  the  case,not  only  in  times  of  prosperity,  when  the  number  of 
indoor  poor  is  low,  but  where,  as  is  often  the  case,  the  wards  are  constructed  of 
greater  width  and  height  than  the  minimum  dimensions  prescribed  in  the  regu- 
lations. In  the  case  of  the  large  sick  wards  of  the  metropolitan,  and  some  pro- 
vincial, modern  Poor-law  infirmaries  the  cubic  space  is  invariably  greater  than 
the  above  amounts,  since,  while  the  amount  of  wall  space  is  the  same,  the  width 
of  the  wards,  instead  of  only  20  feet,  the  minimum  width  prescribed  in  the 
regulations,  is  almost  always  24  feet,  and  the  height  12  feet,  consequently  an 
amount  of  abotit  850  cubic  feet  is  available  for  each  patient ;  this  corre- 
sponds with  the  amount  recommended  by  the  Cubic  Space  Committee,  and 
is  the  basis  upon  which  the  accommodation  of  these  wards  is  calculated  for 
computing  the  annual  grant  received  by  the  Boards  of  Guardians  in  the 
London  district  out  of  the  Metropolitan  Common  Poor  Fund  and  the  fmids 
of  the  County  Council  of  London  under  the  Local  Government  Act,  1888. 
In  the  latter  case  the  requirement  as  regards  the  provision  of  day-room 
space,  as  such,  is  dispensed  with.  As  regards  the  hygienic  arrangements  of 
workhouse  hospitals  and  schools,  it  will  suffice  here  to  refer  to  the  pages 
relatmg  to  hospitals  and  schools  generally;  and  as  regards  the  other 
buildings  of  a  workhouse,  the  principles  ordinarily  applicable  to  hospitals 
have  to  be  followed.  It  will  be  seen  from  the  annexed  block-plan  of  the  new 
and  complete  workhouse  for  the  Gateshead  Union  (fig.  130),  built  from  designs 
by  Messrs.  J.  H.  Morton,  Newcombe,  and  Knowles,  that  what  is  known  as 
the  pavilion  principle  has  been  adopted  for  all  the  principal  buildings.  This 
institution  affords  accommodation  for  916  inmates,  classified  as  foDows  : — 

Main  Building —  Male  Pemale 

Aged  and  infirm     ........  92  66 

Able  bodied 32  62 

Women  with  children    .......  —  30 

Married  couples 12  12 

Schools — 

Boys  and  gii'ls 120  120 

Infants 30  30 

Infirmary — 

Imbeciles 25  25 

Ordinary  sick          .         .      ' 66  66 

Offensive  cases 10  10 

Itch  and  venereal 16  16 

Lying-in  cases —  10 

Isolation  wards 3  3 

Entrance  building — 

Eeceiving  wards 8  8 

Vagrants 36  8 

HOSPITALS 

In  considering  the  conditions  that  go  to  make  a  hospital  healthy  or  the 
reverse,  the  peculiar  circumstances  attending  the  aggregation  of  a  large 
number  of  sick  or  wounded  persons  under  one  roof  need  to  be  carefully  borne 
in  mind. 

Hospitals,  as  charitable  institutions,  exist  for  the  purpose  of  affording 
medical  and  surgical  aid  to  the  sick  poor,  and  for  economical  reasons  it  is 
essential  that  a  considerable  number  of  patients  should  be  treated  together  in 
one  institution.  Further,  for  economy  of  construction  and  nursing,  it  is 
necessary  that  the  patients  should  be  grouped  together  in  general  wards. 


TEE  DWELLING  719 

It  is  not,  however,  necessary  for  the  benefit  of  the  patient  that  he  should 
form  one  of  a  group  of  some  twenty  patients  in  a  ward,  or  of  some  four  or 
five  hundred  patients  in  a  liospital.  On  the  contrary,  it  is  distinctly  an 
•element  of  danger  to  the  individual  patient  that  he  is  one  of  a  large  number 
of  diseased  persons  brought  together  under  one  roof. 

Diseases  arise  de  novo  within  the  wards  of  a  hospital,  which  are  clearly 
traceable  to  direct  contamination  of  air  by  wound  surfaces,  and  are  known 
as  '  traumatic  ; '  and  the  enormous  sacrifice  of  life  to  the  various  forms  of 
septic  disease  which  took  place  in  hospitals  in  former  days,  notably  in  the  old 
Hotel  Dieu  at  Paris,  shows  very  clearly  the  extent  of  the  danger  incurred 
from  this  cause. 

The  aggregation,  therefore,  of  large  numbers  of  diseased  persons  under 
one  roof  can  only  be  justified  if  it  can  be  shown  that  the  advantages  arising 
therefrom  more  than  counterbalance  the  risks  incurred.  The  advantages 
are  twofold:  1st,  to  the  patient,  in  that  the  highest  possible  skill  in  medicine, 
in  surgery,  as  well  as  in  nursing,  is  freely  at  his  disposal,  and  that  everything 
that  science  can  suggest  will  be  applied  to  restore  him  to  health ;  and  2ndly, 
to  society  at  large,  in  the  incalculable  value  of  the  material  for  study  and 
teaching  presented  in  the  wards  of  a  large  hospital. 

The  important  factor,  then,  in  hospital  hygiene  is  that  a  hospital  is  a 
hnilding  which  is  perpetually  producing  within  itself  the  elements  of  danger 
to  its  own  inmates  ;  '  an  establishment  which  never  rests  from  fouling  itself ; 
nor  are  there  any  products  of  its  foulness  —not  even  the  least  odorous  of 
such  products — which  ought  not  to  be  regarded  as  poisonous  '  (Simon, '  Sixth 
Eeport  of  the  Medical  Officer  of  the  Privy  Council,'  1864). 

The  air  of  a  hospital,  then,  is  liable  to  contamination  from  the  following 
causes  :— 

,  1.  The  emanations   or  effluvia  from  the  bodies  and  excretions  of   the 
patients. 

2.  The  presence  of  suppurating  wounds,  with  their  necessary  dressings, 
poultices,  &c. 

3.  Foul  linen,  bedclothes,  &c. 

The  foregoing  are  necessary  and  unavoidable  conditions  common  to  all 
hospitals. 

These  conditions  are  aggravated,  and  their  power  for  evil  intensified  by — 

(a)  Insufficiency  of  cubic  space. 

(&)  Inefficient  ventilation. 

(c)  Improper  arrangements  for  the  removal  of  excreta,  dressings,  poul- 
tices, soiled  linen,  &c. 

{d)  Faulty  arrangement  of  buildings. 

The  neglect  of  proper  measures  of  hygiene  produces  in  a  surgical  ward 
the  class  of  diseases  known  as  '  septic ' — e.g.  erysipelas,  pyaemia,  septicaemia, 
&c.,  and,  as  it  will  be  seen,  it  has  happened  over  and  over  again  that  a 
hospital  has  become  so  saturated  with  the  septic  poison  of  recurrent  out- 
breaks of  disease  that  nothing  short  of  total  destruction  has  availed  to  stamp 
out  the  mischief. 

In  fever  hospitals  it  has  long  been  known  that  overcrowding  in  the  wards 
is  productive  of  the  worst  possible  results,  and  that  the  roughest  sort  of 
shelter  which  admits  of  a  copious  through  current  of  air  is  better  than  a 
permanent  structure  withouit  adequate  means  of  ventilation. 

No  more  striking  example  of  defects  of  construction  and  administration 
■can  perhaps  be  given  than  the  old  Hotel  Dieu  of  Paris.  This  remarkable 
structure  occupied  a  site  close  to  the  Cathedral  of  Notre  Dame,  and  extending 
to  both  sides  of  the  river,  the  two  parts  being  connected  by  two  bridges,  one 


720  HYGIENE 

of  which  was  in  fact  a  ward.  Writing  in  the  year  1788,  Tenon  puts  the 
total  number  of  patients  at  3,-il8,  of  whom  2,627  were  in  the  buildings  on 
the  south  side  of  the  river.  In  this  vast  building,  which  was  nothing  more 
than  one  huge  ward — so  intimate  was  the  intercommunication  between  the 
various  parts —were  assembled  patients  with  fevers,  small-pox,  skin  diseases, 
lying-in  women,  and  surgical  patients.  '  In  the  middle  are  placed  the  most 
infectious  departments,  such  as  clothes  stores,  mortuaries,  dissecting  rooms  ; 
they  [e.g.  the  patients]  are  contained  in  four  or  five  floors  of  wards  joined 
together  and  without  ventilation,  wards  surrounded  by  rooms  for  the  staff, 
which  cool  and  shade  them  ;  where  the  staircases  are  insufficient ;  where 
the  sole  and  only  promenade  is  a  place  encumbered  with  drying  grounds  and 
linen  in  course  of  evaporation  ;  a  monstrous  pile  more  fit  to  prolong  sickness, 
to  destroy  than  to  re-establish  and  preserve  health  '  (Tenon,  '  Memoire  sur 
les  Hopitaux  de  Paris,'  1788). 

The  same  authority  gives  the  total  number  of  beds  provided  for  these 
8,418  patients  as  1,219,  of  which  number  733  were  '  grands  lits,'  and  held 
six  patients  each  !     The  remainder  were  single  beds. 

The  condition  of  the  latrines  is  described  by  the  same  author  as  mere 
masses  of  ordure  :  the  latrines  were  wholly  inadei^uate  in  point  of  numbers, 
and  Avere  in  the  closest  proximity  to  the  wards.  The  extent  to  which  in- 
fection must  penetrate  into  the  wards  is,  says  M.  Tenon,  inexpressible. 

The  immediate  result  of  this  state  of  things  was,  that  one  patient  in 
every  four  and  a  half  died,  without  reckoning  the  deaths  of  children  born  in 
the  hospital  and  transferred  to  the  '  Enfants  Trouvcs.' 

The  buildings  of  the  Hotel  Dieu  were  to  a  large  extent  of  great  age, 
some  portions  dating  back  certaualy  to  the  fifteenth  century,  some  possibly 
older  still.  They  had  been  added  to  and  enlarged  from  time  to  time  without 
much  definite  plan,  except  to  increase  the  number  of  beds  ;  and  the  disasters 
consequent  upon  the  inherent  defects  of  the  structure  were  intensified  by 
overcrowding. 

Of  the  conditions  which  have  been  referred  to  as  aggravating  the  hurtful 
influences  inseparable  from  a  hospital  ward,  insufficiency  of  cubic  space  and 
inefficient  ventilation  are  closely  allied,  and  may  be  taken  the  one  as  the 
complement  of  the  other.  Cubic  space,  indeed,  is  of  little  value  in  itself 
unless  it  is  accompanied  by  ample  means  of  ventilation.  The  importance  of 
this  has  received  striking  illustration  on  many  occasions,  notably  during 
the  Franco-Prussian  War,  when  it  happened  that  a  church  and  a  slaughter- 
house m  Paris  were  about  the  same  time  turned  into  hospital  wards  for 
wounded  soldiers.  In  the  church  gangrene  broke  out  and  the  mortality 
amongst  the  men  was  very  heavy.  In  the  slaughter-house  no  septic  disease 
at  all  appeared,  and  the  men  all  made  good  recoveries.  And  this  happened 
notwithstanding  that  the  cubic  space  per  man  in  the  church  was  greater  than 
in  the  slaughter-house.  The  essential  point  of  difference  in  the  two  buildings 
was  this.  The  slaughter-house  was  a  mere  shed,  with  the  sides  of  louvre 
boards,  and  the  men  therefore  were  practically  in  the  open  air  ;  whilst  in  the 
church  the  walls  were  of  solid  masonry,  and  the  windows  narrow,  and  with 
but  few  openings. 

This  experience  is  also  amply  borne  out  by  that  of  the  hut  hospitals  in 
the  field  during  the  same  war.  These  huts  were  built  of  rough  boarding, 
and  of  so  light  construction  that  the  wind  blew  freely  through  them.  Never- 
theless, there  was  an  almost  complete  absence  of  septic  disease,  while  in  the 
permanent  hospitals,  or  the  houses  temporarily  converted  to  the  purpose, 
hospital  diseases  were  of  frequent  occurrence. 

Instances  could  be  multiplied  to  any  extent  of  the  value  of  pure  air  to 
surgical  patients  ;  and  the  same  remark  applies  equally  to  fever  patients. 


THE  DWELLING  721 

During  an  epidemic  of  typhus  fever  in  Paris  in  1814  the  patients  in  the 
Abattoir  of  Montfaucon,  situated  in  one  of  the  highest  parts  of  Paris,  fared 
much  better  than  those  in  the  regular  hospitals  (Parkes).  In  the  Irish  fever 
of  1847-48  cases  treated  in  the  open  air  and  in  sheds  made  better  recoveries 
than  those  in  the  permanent  buildings  (ibid.). 

A  notable  instance  of  the  mischief  caused  by  the  want  of  efficient  ventila- 
tion is  that  of  the  York  County  Hospital.  This  building  was  designed  to  be 
warmed  and  ventilated  entirely  by  mechanical  means.  There  were  no  fire- 
places and  the  windows  were  all  fixed  and  were  in  some  cases  double.  The 
air  after  being  warmed  by  passing  over  hot  pipes  in  the  basement  was  driven 
into  the  wards  by  an  engine,  and  the  foul  air  was  drawn  out  of  the  wards 
by  heated  shafts.  This  system  remained  in  operation  for  nine  years,  by 
which  time  the  persistent  ill  health  of  the  patients,  and  particularly  the 
constant  occurrence  of  erysipelas  after  the  slightest  incisions,  induced  the  au- 
thorities to  abandon  the  artificial  system  and  resort  to  open  windows  and  fire- 
places, and  upon  this  being  done  erysipelas  disappeared  and  the  cases  did  well. 

Improper  arrangements  for  the  removal  of  excreta  &c.  have  been  largely 
responsible  for  ill  effects  in  hospitals.  The  evil  effects  of  bad  drainage  were 
clearly  recognised  by  Howard  ;  amongst  other  things  he  recommends  bring- 
ing a  '  fine  stream  of  water  '  to  flush  the  drains  at  the  Military  Hospital, 
Dublin,  and  he  notes  with  approval  the  method  adopted  at  the  Royal 
Hospital  at  Plymouth  of  flushing  the  drains  by  means  of  a  tank  holding  180 
tons  of  water. 

The  necessity  for  the  speedy  removal  of  all  f^cal  matter  from  the  proxi- 
mity to  any  dwelling  is  doubly  great  in  the  case  of  a  hospital  ward,  where 
perforce  excretions  are  voided  in  the  ward  by  patients  unable  to  leave  their 
beds,  and  where  also  the  closets  must  be  in  close  communication  with  the 
ward.  In  former  days  the  readiest  mode  of  making  a  water-closet  was  to  cut 
off  a  small  part  of  the  ward  by  means  of  a  boarded  partition  and  within  the 
space  so  enclosed  to  fix  the  apparatus.  Except  for  decency's  sake,  the  ap- 
paratus might  just  as  well  have  been  fixed  in  the  centre  of  the  ward.  It  is 
by  no  means  the  rule,  even  at  the  present  day,  to  find  the  water-closets  sepa- 
rated from  the  ward  by  more  than  a  door  or  at  least  two  doors ;  and  the 
necessity  for  more  effectual  separation  between  the  ward  and  the  closet  than 
is  afforded  by  a  door  is  not  so  invariably  recognised  abroad  as  it  is  in  this 
country.  In  the  late  Mr.  Netten  Radcliffe's  '  Report  on  the  Sanitary  Condi- 
tion of  the  Manchester  Royal  Infirmary  '  ('  Sixth  Annual  Report  of  tlae  Local 
Government  Board,'  Supplement  containing  Report  of  the  Medical  Officer)  he 
attributes  the  insanitary  state  of  the  hospital  partly  to  the  faulty  arrange- 
ment of  the  water-closets.  '  Few  facts,'  he  says,  '  are  perhaps  more  clearly 
established  in  medicine  than  the  mischievous  influence  of  an  atmosphere 
pervaded  with  sewer  air  in  surgical  wards.  Now  the  water-closets,  the  baths, 
the  ward  offices,  and  the  drains  of  the  infirmary  generally  being  placed  within 
the  building,  several  of  the  closets  without  even  direct  communication  with 
the  outer  air,  sewer  air  escaping  from  them  must  necessarily  pass  into  the 
corridors  and  wards.'  That  the  sewer  air  did  actually  make  its  way  into  the 
building,  owing  to  the  faulty  construction  of  the  drains,  is  clearly  shown  in 
a  subsequent  part  of  the  report.  The  same  writer  found  badly  constructed 
drainage  playing  its  part  in  the  promotion  of  insanitary  conditions  at  the 
Radcliffe  Infirmary,  Oxford  [op.  cit.  Appendix,  No.  6). 

Besides  the  removal  of  faecal  and  waste  matters  by  means  of  drains  there 
are  the  soiled  linen,  poultices,  dressings,  &c.,  of  the  patients,  aU  of  which 
are  more  or  less  infective  and  contain  organic  impurities  which  need  to  be 
quickly  removed  and  destroyed.     There  is  also  the  ordinary  refuse  (dust, 

VOL.   I.  8   A 


722  HYGIENE 

kitclien  refuse,  and  so  forth)  wliicli  has  to  be  disposed  of.  The  accumulation 
of  refuse  matter  in  close  proximity  to  the  wards  is  an  arrangement  which 
involves  very  great  danger  to  the  inmates  of  the  ward.  In  the  report  on 
the  Eadcliffe  Infirmary,  just  referred  to,  Mr.  Eadclifl'e  notes  the  close  con- 
tiguity of  the  laundry  to  the  accident  ward,  and  the  practice  of  screening 
ashes  and  refuse  immediately  under  the  windows  of  the  same  ward  as  distinct 
elements  in  the  causation  of  erysipelas  in  that  ward. 

Lastly,  the  inherent  dangers  of  hospital  life  may  be  aggravated  by  im- 
proper arrangement  of  buildings. 

The  defects  of  planning  are  many;  the  most  important  are  the  close 
juxtaposition  bi  blocks  of  several  storeys  shutting  out  the  sun  and  preventing 
the  free  circulation  of  air ;  buildings  in  which  the  wards  are  so  intimately 
connected  that  all  the  patients  are  practically  in  one  and  the  same  atmosphere ; 
and  buildings  where  there  is  direct  atmospheric  communication  between  the 
wards  and  the  mortuary,  out-patient  department,  or  laundry.  Years  ago 
Miss  Nightingale  pointed  out  the  defects  of  plans  such  as  those  of  the  Necker 
Hospital,  Paris,  and  the  Royal  Free  Hospital,  London,  in  which  a  small 
courtyard  is  surrounded  with  high  buildings  on  every  side,  impeding  free  circu- 
lation of  air  ;  of  wards  wherein  the  beds  were  placed  along  dead  Avails  with 
windows  only  at  the  extreme  ends,  such  as  existed  at  the  former  Clinique  de 
la  Maternite,  Paris  ;  of  Netley  Hospital,  and  the  Royal  Hospital,  Portsmouth  ; 
of  wards  such  as  those  in  the  Old  Marine  Hospital,  Woolwich,  where  there 
was  '  no  provision  for  ventilation  worthy  of  the  name,  and  the  wards  are  so 
arranged  that  the  sick  must  of  necessity  be  supphed  with  common  foul  air.' 
('  Notes  on  Hospitals,'  3rd  ed.) 

The  conclusions  arrived  at  by  Messrs.  Bristowe  and  Holmes  in  the 
'  Report  on  Hospitals,'  already  referred  to,^  were  by  no  means  in  favour  of  pavi- 
lion hospitals  as  opposed  to  the  older  type  of  plan  ;  but  it  must  be  remembered 
that  almost  the  only  example  of  pavilion  hospitals  then  in  existence  was  the 
Lariboisiere  at  Paris,  in  which  the  advantages  of  the  paA^ilion  system  are  to 
so  large  an  extent  neutralised  by  the  great  height  of  the  buildings  on  the 
corridors.  Strongly  biassed  as  these  eminent  authorities  undoubtedly  were 
in  favour  of  the  older  form  of  hospital  plans,  they  yet  unhesitatingly  condemned 
the  arrangement  of  a  number  of  small  wards  on  both  sides  of  long  corridors. 
Of  this  latter  type  the  Manchester  Royal  Infirmary  is  an  example,  and  its 
history  unmistakably  illustrates  the  evils  incident  to  such  a  plan. 

Professor  Erichsen  also  condemns  emphatically  what  he  calls  the  '  big- 
house  '  plan,  in  which  are  '  basements  containing  kitchens,  sculleries,  cellars, 
and  the  ordinary  offices  of  a  large  establishment ;  with  an  operating  theatre 
and  dead-house  more  or  less  closely  connected  with  the  main  building  ; 
with  every  floor  filled  with  sick  and  injured  people.'  ( '  Hospitalism,'  by  John 
Eric  Erichsen,  F.R.S.,  1874.) 

Enough  has  been  said  of  the  evils  liable  to  arise  in  consequence  of  faulty 
construction  ;  it  now  remains  to  consider  what  are  the  conditions  necessary 
to  be  observed  in  the  planning  and  construction  of  hospitals  in  order  to  insure 
that,  so  far  as  the  structure  is  concerned,  the  patients  shall  be  treated  under 
circumstances  most  favourable  to  their  recovery. 

The  term  '  hospital '  includes  a  great  variety  of  institutions  having  for  their 
object  the  treatment  and  cure  of  the  sick.  These  institutions  maybe  divided 
into  two  main  sections  of  general  hospitals  and  special  hospitals. 

The  class  '  general  hospitals  '  will  include  all  the  hospitals  which  receive 
all  sorts  of  medical  and  surgical  diseases  except  infectious  fevers  and  chronic 

'  Sixth  Eeport  of  Medical  Officer,  Privy  Council.     (See  p.  719,  ante.) 


THE  DWELLING  723 

incurable  and  mental  diseases.  It  will  also  include  the  large  and  increasing 
class  of  buildings  called  cottage  hospitals  and  the  infirmaries  built  and 
administered  under  the  Poor-law  system. 

Special  hospitals  include  fever  and  small-pox,  lying-in,  consumption, 
children,  incurable  and  chronic,  convalescent,  mineral  water  and  sea  bathing, 
eye,  ear  and  throat,  cancer,  skin. 

Into  the  question  of  the  raison  cVetre  of  special  hospitals  it  is  not  desirable 
in  the  present  work  to  enter ;  the  question  is  a  complex  one  and  belongs 
more  to  the  region  of  medical  ethics  than  to  that  of  hygiene.  This  much 
may  be  said,  however,  that  of  the  necessity  for  special  hospitals  for  fever  and 
small-pox,  and  for  convalescents,  no  reasonable  doubt  exists,  whilst  very 
strong  reasons  exist  for  special  hospitals  for  children,  incurables,  and  perhaps 
phthisis.  From  the  point  of  view  of  hygiene  the  hospitals  which  need 
special  consideration  are  those  of  the  infectious  class,  and  hospitals  for  con- 
sumption, children,  and  convalescents.  The  rest  are  governed  by  the  general 
principles  of  hygiene  applicable  to  all  hospitals,  and  need  not  here  be  sepa- 
rately considered. 

I.     General  Hospitals 

Site. — '  An  ideal  site  for  a  hospital,'  says  Dr.  Mouat,  '  would  be  one  where 
the  conditions  of  soil,  subsoil,  drainage,  water  supply,  and  all  surroundings 
were  most  free  from  local  causes  of  impurity,  and  where  there  were  fewest 
buildings  and  habitations  to  exclude  or  intercept  air  and  light,  or  to  be  them- 
selves active  agents  in  the  creation  of  causes  of  unhealthiness,  such  as  factories, 
workshops,  &c.'  ('  Hospital  Construction  and  Arrangement,'  Part  I.)  Such 
conditions  are  not  always  easily  to  be  fulfilled  when  the  hospital  in  question 
happens  to  be  one  in  a  large  town,  or  if  fulfilled  in  the  beginning  are  apt  to 
'be  greatly  modified  with  the  lapse  of  time  and  the  growth  of  population. 
In  London,  the  Middlesex  and  St.  George's  Hospitals  are  cases  in  point. 
When  first  established,  in  the  first  half  of  last  century,  both  these  institutions 
were  in  the  outskirts  of  London  as  it  then  was,  with  open  fields  all  round 
them.  Now,  though  St.  George's  Hospital  has  the  advantage  of  being  close 
to  two  large  parks,  Ijondon  has  grown  around  and  beyond  both  of  them,  until 
the  outskirts  are  miles  away. 

A  general  hospital,  again,  must  always  be  placed  within  a  reasonable 
distance  of  the  population  whose  needs  it  has  to  serve,  so  that  in  fixmg  upon 
the  site  for  a  hospital  in  a  large  manufacturing  town  regard  must  be  had 
to  the  distance  which  patients  would  have  to  travel  from  the  centres  of 
industry,  where  accidents  would  be  likely  to  occur.  The  importance  of  a 
free  air  space  round  about  a  hospital  is  very  great,  and  a  site  completely  shut 
in  by  high  buildings  is  undoubtedly  an  unsuitable  one.  Dr.  Mouat,  in  the 
work  quoted,  recommends  a  zone  of  aeration  in  extent  equal  to  at  least 
double  the  height  of  the  buildings  surrounding  it ;  and  modern  practice  on 
the  Continent  tends  not  only  to  confirm,  but  to  go  beyond  this  Hmit.  The 
following  table,  extracted  partly  from  a  paper  in  the  '  Practitioner  '  ('  Notes  on 
Modern  Hospital  Construction,'  by  P.  Gordon  Smith,  June,  1888),  illustrates 
the  importance  attached  by  authorities  abroad  to  large  site  area  per  bed : — 

Approximate  area  of 
site  per  bed. 
Germany :  Feet 

Friedrichshain,  Berlin 1,713 

Tempelhof  (military) 1,308 

Moabit 1,144 

University,  Halle 1,575 

University,  Heidelberg 1,070 

3  a2 


724  HYGIENE 


Approsiinate  area  of 
site  per  bed. 

France :  Feet 

Bourges  (military) l.GOO 

St.  Eloi,  Montpelier 1,615 

St.  Denis 1,685 

Belgium : 

Antwerp 1,126 

United  fcJtates  : 

Johns  Hopkins,  Baltimore 1,679 

England : 

&t.  Thomas's,  London 660 

Great  Northern  Central 293 

Middlesex 273 

St.  George's 166 

In  several  of  the  hospitals  in  the  foregoing  list  the  very  large  proportion 
of  site  area  to  bed  is  due  to  the  fact  that  the  ward  pavilions  are  all  limited 
to  one  storey  ;  a  mode  of  construction  that  has  not  found  very  much  favour 
in  England,  and  owing  to  the  great  value  of  land  is  scarcely  ever  likely  to 
be  adopted  in  London  or  the  larger  provincial  towns. 

Where  it  is  possible  to  exercise  discretion  in  the  choice  of  a  site,  regard 
should  be  had  to  the  following  conditions  :  The  site  should  be  sheltered  from 
the  prevailing  rainy  winds  of  the  district,  and,  if  such  exist,  from  unhealthy 
winds  also  ;  a  gentle  slope  is  usually  preferable  to  flat  ground,  and  the  side 
of  a  hill  to  the  bottom  of  a  valley.  Undrained  clay  soils,  or  thin  strata  of 
gravel  overlying  clay,  are  both  soils  of  an  undesirable  nature. 

General  Arrangement. — The  disposition  of  the  several  parts  of  a  hospital 
in  relation  to  each  other  necessarily  depends  greatly  on  the  size  of  the  hospital 
and  on  the  form  and  area  of  the  site.  But  the  important  aim  to  be  kept  in 
view  is  the  efl'ective  separation  of  the  wards  from  the  other  parts  with  due 
regard  to  economy  of  construction.  The  pavihon  system  was  undoubtedly 
a  step  in  advance  on  the  old  '  big  house  '  plan  ;  but  in  its  inception  it  was 
regarded  entirely  as  a  means  of  obtaining  more  efl'ective  ventilation  to  the 
wards,  and  had  no  reference  to  the  separation  of  parts.  It  is,  indeed,  no 
uncommon  thing  to  find  a  large  pavilion  hospital,  of  comparatively  modern 
date,  the  lowest  floor  of  one  pavilion  occupied  by  the  laundry,  while  in 
another  is  found  the  out-patient  department.  Even  the  mortuary  and  jjost- 
viortem  room  are  not  infrequently  to  be  found  occupying  a  portion  of  the 
lowest  floor  of  a  ward  block. 

In  order  to  arrive  at  some  general  principles  of  planning,  it  is  necessary 
to  consider  what  are  the  essential  parts  of  a  general  hospital. 

In  every  hospital  of  whatever  size  there  must  always  be — 

(a)  Administration  oflices.  These  comprise  the  official  rooms,  i.e.  board 
room,  secretary's  oflice,  steward's  office,  &c. ;  the  domestic  offices,  i.e. 
kitchens,  larders,  sculleries,  storerooms,  and  the  sleeping  accommodation 
for  resident  staff  and  servants. 

(b)  Wards  and  their  oiflces. 

(c)  Operation  room,  or  theatre,  with  subsidiary  rooms  attached. 
{d)  Out-patient  department. 

(e)  Mortuary  dind  j^ost-mortem  room. 

To  these  will  be  added  in  the  case  of  very  large  hospitals — 

(/)  Laundry. 

[g)  Medical  school. 

{h)  Nursing  home. 

In  several  recent  examples  of  hospitals  abroad  each  one  of  the  depart  - 


THE  DWELLING  725 

ments  lias  been  placed  in  an  absolutely  separate  and  distinct  building,  in 
some  cases  unconnected  by  even  covered  ways.  At  Heidelberg,  for  example, 
the  University  Hospital  consists  of  sixteen  distinct  buildings,  five  of  which 
are  devoted  to  surgical  patients,  one  to  eye  patients,  four  to  medical  cases, 
and  one  to  skin  cases  ;  the  rest  comprising  the  administration  block,  patho- 
logical institute,  mortuary,  kitchen,  and  laundry.  The  ward  pavilions  are 
connected  together  by  covered  ways,  consisting  merely  of  roofs  supported  on 
posts,  and  quite  open  at  the  sides. 

Very  similar  to  the  last  is  the  Hopital  de  I'lsle,  or  Insel  Spittal,  at  Berne ; 
but  here  there  are  no  covered  communications. 

At  the  Johns  Hopkins  Hospital,  Baltimore,  the  various  buildings  are  all 
•detached,  and  there  are  no  connecting  corridors. 

The  drawbacks  to  this  mode  of  arrangement  are  :  (1)  the  great  extent 
of  land  necessarily  occupied  ;  (2)  the  greater  proportional  cost  involved  both 
for  land  and  buildings  ;  and  (3)  the  increase  in  cost  of  administering  such  a 
huilding  consequent  upon  the  greater  distances  between  the  various  parts. 

The  really  essential  parts  of  such  a  building  may  be  summed  up  as 
follows  :  (1)  separation,  or  at  any  rate  avoidance,  of  intimate  connection 
hetween  the  wards  and  the  administration  block ;  (2)  separation  of  medical 
from  surgical  wards ;  (3)  absolute  atmospheric  disconnection  between  the 
wards  on  the  one  hand,  and  the  mortuary,  laundry,  and  out-patient  de- 
partment on  the  other. 

To  fulfil  these  conditions  by  arranging  a  series  of  one  or  two  storey 
buildings  on  a  plot  of  ground  of  such  ample  dimensions  as  that  of  either  of 
the  three  hospitals  mentioned  is  simple  enough,  but  in  London  and  in  large 
towns  where  land  is  of  great  value  such  a  plan  becomes  a  practical  impos- 
sibility, unless,  indeed,  it  is  contended  that  the  beneficial  results  to  the 
patients  are  of  such  value  as  to  justify  the  enormously  increased  cost. 

That  the  essential  parts  of  the  system  can  be  obtained  without  so  lavish 
an  extent  of  land  being  required  is  evidenced  by  the  plan  (fig.  131)  of  the 
new  Great  Northern  Central  Hospital,  London.  This  hospital  occupies  a 
site  of  less  than  a  third  in  extent  of  that  at  Heidelberg.  Nevertheless,  it 
will  be  seen  from  the  plan  that  the  wards  are  practically  isolated  from  each 
other  and  from  the  rest  of  the  hospital ;  that  the  operation  room  is,  though 
in  easy  communication,  not  in  direct  atmospheric  connection  with  the  wards  ; 
that  the  mortuary  and  the  out-patient  departments  are  distinct  and  separate 
buildings. 

So  far,  then,  the  essential  principles  of  the  separation  of  parts  are  com- 
plied with  in  this  plan  with  a  comparatively  small  area  of  site  per  patient. 

The  value  of  a  sufficiency  of  open  space  about  a  hospital  is  undoubtedly 
very  great ;  but  in  cases  where  the  cost  of  land  is  so  great  as  it  is  in  London 
and  some  provincial  towns  the  absolute  necessity  for  so  large  an  area  of  site 
per  bed  may  reasonably  be  questioned.  And  although  the  proportion  of  site 
to  patients  at  the  Great  Northern  Central  Hospital  is  by  no  means  what  it 
might  be  without  undue  extravagance,  yet  it  must  be  admitted  that  even  on 
this  restricted  site  it  has  been  possible  to  obtain  the  essential  conditions  of 
separation  of  parts. 

Administration  Block. — The  general  arrangements  of  this  part  of  a 
hospital  will  necessarily  vary  with  the  size  of  the  hospital.  In  a  large  building 
the  offices  will  be  numerous  and  the  residential  part  extensive  ;  but  the  modern 
custom  of  housing  the  nursing  staff  in  a  separate  building  very  much  reduces 
the  amount  of  accommodation  to  be  provided  in  the  main  administration 
block.  In  some  modern  hospitals  also  the  kitchen  offices,  with  the  dormi- 
tories for  servants,  are  placed  in  a  separate  block,  thus  stiU  further  reducing 


726 


HYGIENE 


the  main  block.     In  the  majority  of  English  hospitals  the  administration 
block  comprises  the  secretary's  office  or  offices,  boardroom,  residences  for 


CREflT  NORTHERN  CENTRAL  hOSPlT/IL 
tiOLLOWftY  ROHO 
LONDON  J\t. 


knuof 


NUET  VtKTlLATOM 


MOLLOWAV  ROAD 


Fig.  131. 


medical  staff,  matron  and  secretary,  steTvard's  office,  storerooms,  kitchen 
offices,  and  servants'  dormitories.  To  these  should  be  added  an  office  for  the 
matron,  and  a  consultation  room  for  the  visiting  staff.     The  kitchen  offices 


THE  DWELLING  727 

should  be  placed  on  the  top  floor,  and  the  stores  in  the  basement,  with  com- 
munication between  the  two  by  means  of  a  lift  and  speaking-tube.  Separate 
dining-rooms  mvist  also  be  provided  for  the  male  and  female  servants. 

Wards. — It  is  now  pretty  generally  agreed  that  the  pavilion  type  of  ward  is 
the  most  suitable  one  for  general  hospitals,  but  the  precise  form  of  the  ward 
admits  of  variations.  The  most  general  form  is  that  of  a  rectangle  varying 
from  20  to  30  ft.  in  width,  and  from  30  to  over  100  ft.  in  length.  Two  other 
forms  exist — one  the  circular,  the  other  octagonal.  The  circular  form  has 
been  adopted  in  several  instances,  and  its  merits  will  be  discussed  later  ;  of 
the  octagonal  form  only  one  example  exists,  that  at  the  Johns  Hopkins 
Hospital,  Baltimore. 

The  dimensions  of  a  ward  are  governed  by  two  conditions:  (1)  the 
number  of  patients  to  be  associated  together,  and  (2)  the  cubic  space  and 
floor  area  to  be  allotted  to  each  patient.  It  is  impossible  to  lay  down  any 
hard-and-fast  rules  for  the  number  of  patients  to  be  put  into  one  ward. 
Consideration  of  nursing  economy  points  to  large  wards.  Consideration  of 
hospital  hygiene  points  equally  to  small  wards.  From  the  former  point  of 
view  a  convenient  number  for  a  ward  is  thirty-two,  which  number  will  be 
found  at  Lariboisiere,  the  Herbert  Hospital,  and  Leeds  Infirmary.  On  the 
other  hand,  at  the  newest  hospitals  on  the  Continent  the  average  number  in 
a  ward  will  be  found  to  be  about  sixteen.  There  can  be  no  doubt  that, 
especially  for  surgical  wards,  the  smaller  the  number  of  patients  associated 
together  the  better.  A  large  number  of  small  wards  gives  greater  facilities 
for  classification  of  cases  than  a  small  number  of  large  wards.  The  question 
is,  however,  very  largely  one  of  cost,  and  it  cannot  at  present  be  said  with 
absolute  certainty  that  the  gain  to  the  patients  in  small  wards  more  than 
outweighs  the  additional  outlay  involved. 

Having  determined  the  number  of  beds  in  each  ward,  it  is  necessary  to 
provide  that  each  patient  shall  have  sufficient  space  both  of  floor  and  of  air. 
What  constitutes  '  sufficient '  space  depends  upon  the  question  of  ventila- 
tion. And  by  ventilation  is  meant  such  a  change  of  air  to  each  patient  as 
will  secure  to  him  a  constant  supply  of  the  purest  available  air  without 
draught,  and  at  a  proper  temperature.  This  supply  should,  according  to  the 
best  authorities,  be  practically  unlimited,  or  perhaps  it  would  be  more  correct 
to  say  that  it  should  be  capable  of  unlimited  increase  when  occasion  demands. 
The  figures  for  floor  space  and  cubic  space  in  general  hospitals  considered 
necessary  by  Drs.  Parkes  and  De  Chaumont  are  100  to  120  ft.,  and  1,500  to 
2,000  ft.  respectively.  General  Morin  gives  60  to  70  cubic  metres  (2118'6 
to  2471'7  ft.).  The  Paris  hospitals  have  a  mean  of  43  cubic  metres 
(1518'33  ft.),  while  the  London  hospitals,  according  to  the  same  authority, 
average  52  metres  (1826"12  ft.)  per  bed.  The  latter  figure  is  misleading, 
inasmuch  as  some  of  the  large  hospitals  (Middlesex,  St.  George's,  St.  Mary's, 
Westminster)  are  entirely  omitted  from  the  list  upon  which  the  average 
is  made. 

As  a  practical  deduction  from  these  and  like  facts,  it  will  be  found  that 
100  square  feet  is  the  minimum  floor  space  in  general  wards,  and  that  this 
amount  should  be  increased  for  acute  surgical  cases  and  for  clinical  wards. 

In  the  latter  case  space  is  required  for  the  students  who  gather  round 
the  beds  for  clinical  instruction.  At  the  Edinburgh  Eoyal  Infirmary — one  of 
the  largest  medieal  schools  in  the  United  Kingdom — the  floor  space  is  149  feet 
per  bed,  and  at  Halle — also  a  large  teaching  centre — it  is  140  feet ;  on  the 
other  hand,  the  floor  space  at  the  Johns  Hopkins  Hospital,  on  the  planning  of 
which  an  immense  amount  of  thought  and  care  has  been  bestowed,  is  only 
105  feet. 


728  .  HYGIENE 

With  regard  to  cubic  space,  1,500  feet  should  certainly  be  taken  as  the 
minimum  for  acute  cases,  though  for  wards  in  which  a  proportion  of  mild  or 
convalescent  cases  are  mixed  with  others  of  an  acute  nature  the  cubic  space 
may  with  safety  be  as  low  as  1,200  feet.'  In  certain  cases  2,000  feet  will  not 
be  found  excessive  ;  and  in  some  instances,  as  at  Edinburgh  Royal  Infirmary,''' 
Antwerp,^  Heidelberg,^  Halle  ^  (surgical  wards).  Hotel  Dieu  (Paris),*^  St. 
-Denis,^  Bichat,**  St.  Eloi,^  Genoa,'°  this  amount  is  largely  exceeded. 

The  requisite  amount  of  cubic  space  must,  however,  to  a  large  extent  depend 
upon  the  means  of  ventilation  adopted ;  and  it  may  safely  be  said  that  with 
our  English  habits  of  constantly  open  windows  and  open  fireplaces  a  less 
amount  of  cubic  space  is  permissible  than  when  the  mechanical  means  of 
ventilation  so  largely  prevalent  abroad  are  adopted. 

It  will  thus  be  seen  that  no  hard-and-fast  rules  can  be  laid  down  either 
for  floor  area  or  cubic  space  per  patient,  but  that  the  amounts  to  be  provided 
must  be  dependent  on  circumstances. 

The  particular  form  which  a  ward  should  take  may  either  be  rectangular, 
circular,  or  octagonal. 

The  rectangle  is  the  most  familiar  form,  and  being  most  simple  in  con- 
struction has  been  until  quite  recently  universal.  The  idea  of  a  circular 
ward  owes  its  origin  in  this  country  to  the  late  Professor  Marshall,  F.R.S., 
who  in  1878  suggested  its  adoption  in  a  paper  read  by  him  at  the  Social 
Science  Congress  of  that  year''  and  subsequently  published.  Curiously 
enough,  the  same  idea  had  about  the  same  time  occurred  to  a  Belgian 
architect,  M.  Baeckelmans,  who  in  1872  submitted  plans  for  a  new  civil 
hospital  at  Antwerp,  which  were  with  some  modifications  subsequently 
carried  out. 

Professor  Marshall's  advocacy  of  the  circular  form  was  based  on  (a)  free- 
dom of  frontage  to  all  points  of  the  compass,  (h)  great  accessibility  to  light 
and  air,  (c)  greater  area  contained  within  a  given  length  of  wall  in  a  circle 
than  in  a  rectangle,  {d)  superior  ventilability,  and  (e)  more  equal  warmmg. 
He  also  considers  that  a  circular  ward  can  be  better  administered  and  would 
present  a  more  cheerful  and  agreeable  appearance  than  a  long  straight  ward. 
The  opponents  of  the  system  asserted  on  the  other  hand  that  a  circular  ward 
would  be  dark  or  inadequately  lighted,  that  it  would  be  difficult  of  super- 
vision, that  the  patients  would  be  uncomfortably  in  vieAV  of  each  other,  that 
the  ventilation  would  be  difficult  if  not  impracticable,  and  finally  that  the 
construction  would  be  excessively  costly. 

While  it  is  not  yet  possible  to  speak  positively  on  the  relative  advantages 
of  circular  and  rectangular  wards,  it  is  certain  that  the  objections  cited  above 
have  in  practice  been  entirely  disproved.  In  all  the  circular  wards  yet  erected 
the  question  of  lighting,  ventilation,  and  supervision  have  been  dealt  with 
most  efficiently,  and  no  complaint  has  ever  yet  been  made  by  the  patients  of 
any  discomfort  arising  from  the  form  of  the  ward. 

The  objections  on  the  score  of  cost  have  been  entirely  based  upon  a 
fallacious  system  of  argument,  which  presumed  that  no  ward  should  ever 
hold  less  than  twenty- eight  patients.  It  is  easy  to  show  that  the  circular 
form  is  extravagant  and  indeed  impracticable  when  the  number  of  patients 

'  Le  Fort,  Note  stir  qiiclq^ues  imnts  clc  Vhyrjiena  hosjntalierc  en  France  eten  Angleterre, 
1862. 

-  2,015  to  2,039  ft.  ^  2,525  ft.  •*  2,050  ft.  =•  2,207  ft. 

«  2,222  to  2,411  ft.  '  2,457  ft.  «  2,205  ft.  "  2,328  ft. 

'»  2,644  ft. 

"  On  Circular  System  of  Hospital  Wards.  By  John  Marshall,  F.B.S.  With  remarks 
and  illustrations  by  Percival  Gordon  Smith.    London,  1878. 


THE  DWELLING 


729 


Fig.  132. 


in  a  ward  passes  a  certain  limit ;  but  it  is  a  reductio  ad  absurdum  to  first 
fix  the  limit  at  an  impossible  number  and  then  condemn  the  system  on 
that  ground  alone.  Doubtless  the  construction  of  a  circular  building  is 
more  costly  than  that  of  a  rectangular  one,  the  conditions  of  each  being 
identical  except  as  to  form ;  but  judging  from  the  very  few  examples  that 
have  yet  been  erected  it  may  safely  be  said  that  the  difference  in  cost 
need  not  exceed  about  two  per  cent.  It  is  curious  to  note  that  the  opposition 
to  the  circular  system  has  emanated  almost  entirely  from  architects  and  not 
from  medical  men. 

Circular  wards  exist  at  the  following  hospitals  :  Antwerp  (Civil  Hospital), 
Greenwich  (Miller  Memorial),  Hastings,  Burnley  (Victoria  Hospital),  Liverpool 
(Eoyal  Infirmary),  Milton  near  Gravesend  (Military),  Seaforth  near  Liverpool 
(Military),  New  York  (Cancer),  and  the  Workhouse  Infirmary,  Hampstead. 
The       rectangular 

pavilion  ward  is  of  two 

forms  :  (1)  the  double 

ward  (fig.  132),  which 

consists  of  two  ordinary 

wards   placed  side  by 

side,  with  the  dividing 

wall  pierced  at  inter- 
vals with  arches,  and 

having    four    rows  of 

beds  between  the  two 

external    walls :      ex- 
amples   of  this   ward 

may    be   seen   at    St. 

Bartholomew's,       the 

London  Hospital,  Guy's  Hospital,  and  the  London  Fever  Hospital ;  in  a 

modified  form  at  King's  College  Hospital  and  in  some  Poor-law  infirmaries. 

(2)  The  ordinary  single  ward  (fig.  133),  which  is  varied  only  in  size  and  in 

the    arrangement    of    the 

beds.     The  latter  are  either 

placed     in    pairs,     against 

the  piers  dividing  the  win- 
dows, as  at   St.  Thomas's, 

London,    Tenon    Hospital, 

and  the  Hotel  Dieu,  Paris  ; 

or   singly,   having   a    win- 
dow   intervening    between 

each  bed  and  the  next.  The 

latter  arrangement  is  much 

to  be  preferred,  as  it  more 

effectually     isolates      each 

patient  from  his  neighbours, 

and  permits  of  equal  spac- 
ing of  the  beds.      No  bed 

ought  to  be  nearer  to  the 

next  one  than  five  feet ;  then 

each  patient  will  have  a  minimum  of  eight  feet  clear  wall  space.      In  large 

wards  for  acute  cases,  this  space  ought  to  be  increased  to  ten  feet. 

From  what  has  been  said  it  will  be  seen  that  award  should  have  two  rows 

of  beds,  and  that  between  each  bed  and  the  next  there  should  be  a  window. 

As  usually  arranged,  this  would  give  in  a  ward  for,  say,  twenty  beds  eighteen 


Fig.  133. 


730  HYGIENE 

windows,  nine  on  each  wall.  Therefore,  at  each  end  of  the  ward  there  would 
be  two  beds  with  a  window  at  one  side  only.  The  practical  result  is  that  the 
space  occupied  by  these  end  beds  is  not  so  well  ventilated  as  the  rest  of  the 
ward,  and  it  has  been  often  observed  that  the  cases  treated  in  them  do  not 
fare  so  well  as  those  in  the  remainder.  The  remedy  for  this  is  to  place 
an  additional  window  between  the  end  of  the  ward  and  the  end  bed  on  each 
side,  increasing  if  necessary  the  length  of  the  ward  in  order  to  do  so,  and 
giving  the  extra  length  entirely  to  the  end  beds.  Thus,  in  a  ward  of  twenty 
beds  there  should  be  twenty-two  windows  instead  of  eighteen.  These  end 
windows  need  not  be  as  wide  as  the  other  windows,  but  may  be  just  sutii- 
ciently  wide  to  obtain  the  necessary  movement  of  air. 

There  is  no  better  form  of  window  for  a  ward  than  the  ordinary  double- 
hung  sliding  sash  with  a  hopper  light  above.  The  glass  line  should  be 
sufficiently  low  to  allow  the  patients  to  see  out  of  window  without  standing 
up,  and  the  top  of  the  window  should  be  as  near  the  ceiling  line  as  it  is 
possible  to  get  it.  The  lower  sash  should  be  furnished  with  a  deep  bottom 
rail,  and  on  the  sill  should  be  fixed  a  deep  board  instead  of  the  usual  shallow 
bead.  The  lower  sash  can  by  this  means  be  opened,  and  a  current  of  air  with 
anuj)ward  tendency  admitted  between  the  upper  and  lower  sash,  without  any 
direct  draught  at  the  sill  level.  The  part  above  the  transome  should  be  hinged 
at  the  bottom,  and  made  to  fall  inwards  to  an  angle  of  about  G0°,  and  the 
sides  protected  with  glazed  cheeks  to  prevent  down  draught. 

The  amount  of  window  area  should  bear  some  definite  proportion  to  the 
cubic  space  of  the  ward.  It  is  not  very  easy  to  give  any  definite  rule  for 
this  proportion,  which  will  be  applicable  to  all  wards  alike,  but  in  practice 
it  will  be  found  that  a  foot  of  window  surface  to  from  sixty  to  eighty  feet 
of  cubic  space  is  a  useful  proportion  to  work  upon.  Dr.  Thorne  Tliorne  con- 
siders that  in  a  well-constructed  and  efficiently  warmed  building  the  amount 
of  vraidow  surface  should  not  vary  much  beyond  these  limits,  and  that  a 
proportion  of  one  square  foot  to  seventy  cubic  feet  is,  as  a  rule,  the  most  advan- 
tageous. The  failure  to  maintain  sufficient  warmth,  and  at  the  same  time 
to  properly  ventilate  the  wards  of  the  Children's  Hospital  at  Pendlebury,  is 
attributed  by  Dr.  Thorne  Thorne  to  the  excessive  proportion  of  window 
surface  to  cubic  space,  which  at  that  hospital  amounts  to  one  foot  of  window 
surface  to  thirty-five  feet  of  cubic  space. 

In  exposed  situations  it  is  desirable  to  provide  additional  protection 
against  loss  of  heat  by  radiation  by  glazing  the  windows  with  two  sheets  of 
glass,  with  an  interspace  of  about  three-quarters  of  an  inch  between  the 
two. 

The  most  suitable  material  for  the  surface  of  the  walls  of  a  ward  would 
be  one  which  should  present  an  absolutely  impervious  washable  surface 
without  joints,  and  not  liable  to  crack.  Supposing  it  were  possible  to  cover 
the  walls  entnely  with  glass  without  joints,  such  a  surface  would  be  without 
doubt  an  absolutely  perfect  one.  Such  a  thing  is,  however,  impossible. 
Various  modes  of  approximating  to  such  a  result  have  been  suggested  ; 
amongst  others,  marble,  glazed  bricks  and  tiles,  and  polished  Paiian  cement. 
Marble  walls,  if  the  slabs  could  be  got  in  sufficiently  large  sizes,  would  be 
excellent,  but  can  hardly  be  regarded  as  practicable  because  of  the  excessive 
cost.  Glazed  bricks  and  tiles  are  the  next  best  substitutes,  but  in  both  cases 
there  is  the  objection  of  the  numerous  joints  and  the  impossibility  of  getting 
a  perfectly  even  face.  Polished  Parian  cement  was  at  one  time  thought  to  be 
a  perfectly  impervious  surface,  but  experience  has  shown  that  it  is  scarcely, 
if  at  all,  superior  to  ordinary  plaster,  while  much  more  costly.  Until  some 
process  is  discovered  by  which  a  plastered  surface  can  be  rendered  impervious 


THE  DWELLING  731 

and  washable,  the  best  way  to  treat  the  walls  of  a  ward  is  to  form  a  dado 
of  cement  of  a  height  that  can  be  reached  by  the  hand,  and  to  paint  and 
varnish  the  surface  ;  above  that  to  finish  with  ordinary  plaster  and  distemper. 
The  varnished  surface  can  be  washed  in  the  ordinary  course  of  ward  clean- 
ing, and  the  distemper  can  and  ought  to  be  renewed  yearly. 

The  construction  of  a  ward  floor  ought  always  to  be  what  is  known  as 
fireproof;  that  is,  of  iron  beams  or  joists  embedded  in  concrete.  Upon  the 
surface  of  the  concrete  the  wooden  floor,  formed  preferably  of  oak  or  teak, 
should  be  laid  solid.  Apart  from  the  fire-resisting  nature  of  this  construction, 
in  itself  an  element  of  importance  in  a  hospital,  the  advantage  is  gained  of 
there  being  no  space  underneath  the  wooden  floor  to  harbour  accumulationa 
of  decaying  organic  matter,  and  each  ward  is  more  efi'ectually  cut  ofi"  from 
the  ward  above  and  below. 

An  important  point  to  observe  in'  every  part  of  a  ward,  as  indeed  also  in 
other  parts  of  a  hospital,  is  the  strict  avoidance,  as  far  as  possible,  of  all 
projections,  ledges,  or  angles  in  which  dust  can  lodge.  Thus  all  the  corners 
of  the  panels  of  doors  and  the  panes  of  window  sashes  should  be  moulded 
instead  of  square,  and  no  mouldings  or  recesses  (called  by  carpenters 
*  quirks ')  should  be  permitted.  The  vertical  and  horizontal  angles  of  the 
walls,  ceilings,  and  floors  should  likewise  be  rounded,  and  the  same  rigid 
avoidance  of  corners  should  be  observed  as  far  as  practicable  in  the  furniture. 

Ward  Offices. — Certain  rooms,  which  for  convenience  sake  may  be 
grouped  together  as  ward  offices,  must  be  placed  in  immediate  contiguity 
to  the  ward.  These  offices  all  have  their  part  in  the  economy  of  the  ward 
administration  ;  upon  their  completeness  will  depend  much  of  the  comfort 
and  regularity  \n.i\x  which  the  ward  is  worked. 

The  duty  room,  or  ward  kitchen,  is  a  room  in  which  the  plates,  cups,  and 
saucers,  &c.,  used  in  the  wards  are  kept  and  washed,  and  in  which  a  certain 
amount  of  invalid  cooking  is  done.  If  there  be  no  separate  nurses'  room 
attached  to  the  ward,  the  duty  room  is  the  place  where  disinfectants,  and 
sometimes  medicines,  are  kept,  but  these  should  always  be  under  lock  and 
key,  and  in  charge  of  the  head  nurse  or  Sister. 

A  nurses'  room  is,  by  some  authorities,  considered  a  necessity ;  in  most 
older  hospitals  there  is  a  bedroom  and  sitting-room  combined  attached  to 
each  ward  for  the  head  nurse,  but  many  eminent  authorities  consider  that 
while  on  duty  a  nurse's  place  is  in  the  ward,  and  that  when  off  duty  she 
should  be  entirely  removed  from  the  ward  atmosphere.  From  a  health 
point  of  view  the  latter  arrangement  is  undoubtedly  correct,  and  if  a  nurses' 
room  be  provided  near  the  ward,  it  ought  certainly  to  be  a  sitting-room  only, 
and  not  a  bedroom. 

These  two  rooms  should  of  course  be  at  the  corridor  or  entrance  end  of 
the  ward,  and  may  be  provided  with  windows  overlooking  the  ward,  though 
the  practical  utility  of  such  appliances  is  questionable. 

One  or  two  small  wards  or  rooms  for  one  patient  should  in  large  hospitals 
be  arranged  at  the  corridor  end  for  cases  requiring  special  treatment,  or  such 
as  for  some  reason  would  be  better  treated  alone  than  in  a  large  ward. 

In  close  proximity  to  the  duty  room  should  be  a  linen  cupboard  for  the 
store  of  ward  linen,  a  cupboard  for  patients'  own  clothes,  and  a  small  larder 
for  milk,  bread,  &c.  All  these  should  be  properly  ventilated  and  lighted. 
There  should  also  be  provided  a  suitable  place  in  which  to  stand  the  coal  trolley, 
the  food  trolley  (for  bringing  meals  from  the  hfc),  and  a  wheeled  basket  for 
dirty  linen.  These  seem  trivial  details,  but  the  importance  of  thinking  of 
these  things  beforehand  and  providing  for  them  is  not  slight. 

The  water-closets  for  the  patients  and  the  sink-room  are  usually  and 


732  HYGIENE 

most  conveniently  placed  at  the  further  end  of  the  ward.  Li  many  cases  also 
the  bathroom  is  likeAnse  at  the  same  end.  It  is  of  importance  that  the 
atmospheric  connection  between  the  ward  and  the  water-closets  should  be 
severed  as  completely  as  possible,  while  at  the  same  time  access  to  these 
offices  must  be  easy  and  direct.  To  effect  this  it  is  necessary  to  interpose 
between  the  ward  and  the  closets  a  lobby  having  windows  on  each  side  for 
*  through  '  or  '  cross  '  ventilation.  At  each  end  of  the  lobby  is  a  door,  and 
by  this  means  the  air  from  the  closets  cannot  easily  be  blown  or  drawn  into 
the  ward. 

In  America  it  is  usual  to  place  the  water-closets  at  the  entrance  end  of 
the  ward  and  to  rely  wholly  upon  mechanical  ventilation  appliances  to  prevent 
a  flow  of  air  from  the  closets  to  the  ward.  This  plan  has  the  advantage  of 
leaving  the  other  end  of  the  wards  free  for  balconies  or  sun  rooms  ;  but  in  this 
country,  where  natural  ventilation  is  imiversally  used,  such  an  arrangement 
is  impracticable. 

The  proportion  of  water-closets  to  patients  should  not  be  less  than  one  to 
ten,  and  in  none  but  very  small  Wards  should  there  be  less  than  two  closets. 

The  sink-room  should  be  large  enough  to  hold  a  good-sized  slop-sink  with 
a  sink  for  cleaning  vessels,  a  draining  board,  shelves  and  racks  for  bedpans 
and  other  crockery,  and  brooms.  A  cupboard  having  free  ventilation  to  the 
outer  air,  and  a  door  as  nearly  air-tight  as  possible,  should  be  constructed  in 
this  room  for  keeping  vessels  in  which  fteces  or  urine  have  to  be  temporarily 
preserved. 

The  bathroom  need  not  of  necessity  be  separated  from  the  ward  by  a 
lobby  ;  neither  is  there  any  special  advantage  in  placing  it  at  the  same  end 
as  the  water-closets.  Besides  the  bath,  it  should  contain  lavatory  basins  in 
the  proportion  of  about  one  to  every  five  or  six  patients.  The  bath  should 
be  so  placed  that  a  patient  can  be  easily  lifted  in  and  out,  and  carried  to 
and  from  the  ward  in  a  recumbent  position.  For  these  and  other  reasons 
the  bath  should  have  its  foot  only  to  the  wall. 

Balconies  and  Barrack  Wards. — The  treatment  of  patients  in  the  open 
air  is  much  more  resorted  to  on  the  Continent  and  in  America  than  in 
this  country.  In  most  German  hospitals  there  are  covered  balconies  in 
which  patients  are  kept  duruig  the  summer  months  by  night  as  well  as  by 
day.  In  America  the  '  sun  room '  at  the  end  of  the  ward  is  a  common 
feature.  The  '  baraque,'  as  it  is  used  in  Germany,  is  an  institution 
practically  unknown  here.  It  consists  of  a  wooden-framed  hut  raised  about 
eighteen  inches  or  two  feet,  or  sometimes  more,  from  the  earth  or  brick 
piers.  The  spaces  between  the  upright  posts  are  protected  by  curtains  only, 
which  are  drawn  at  night  or  by  day  to  keep  off  the  sun  or  rain.  The 
patients,  therefore,  are  practically  in  the  open  air  ;  such  a  '  baraque  '  exists 
at  the  hospital  at  Basel,  and  is  devoted  entirely  to  children  (surgical  patients 
only),  who  are  kept  there  day  and  night  from  May  to  October. 

Operation  Boom. — The  operation  room  will  vary  in  size  according  to 
circumstances,  from  the  small  room,  just  large  enough  to  hold  the  table  with 
the  necessary  adjuncts,  to  the  theatre  of  a  large  clinical  hospital,  with  its 
tiers  of  seats  for  students  numbering  often  some  hundreds.  In  large  hospitals 
there  are  usually  one  or  two  minor  operation  rooms,  in  addition  to  the  large 
theatre.  These  smaller  rooms  are  specially  needed  for  eye  operations,  for 
which  a  light  at  a  special  angle  is  necessary,  and  which  cannot  be  performed 
in  a  theatre  lighted  entirely  from  the  top.  They  are  also  needed  for  ovarian 
cases,  when  these  are  treated  in  a  general  hospital. 

The  operation  theatre  ought  to  be  separated  as  completely  as  possible 
from  the  wards  and  the  other  parts  of  the  hospital.     The  absolute  isolation 


THE  DWELLING  733 

of  the  operation  theatre  is  by  some  surgeons  considered  so  important  that  in  ' 
some  foreign  hospitals — as,  for  instance,  at  Chartres  and  at  Friedrichshain, 
Berhn — it  forms  an  entirely  detached  building,  and  patients  have  to  be  con- 
veyed thither  in  a  hand  ambulance  through  the  garden. 

This,  perhaps,  is  carrying  the  principle  to  an  extreme  point ;  the  opera- 
tion theatre  ought,  however,  to  be  so  placed  that  atmospheric  communication 
between  it  and  the  wards  and  the  domestic  offices  of  the  hospital  is  entirely 
precluded. 

The  same  precautions  to  ensure  absolute  cleanliness  must  be  taken  as  in 
a  ward,  and  everything  of  an  absorbent  nature  should  be  as  far  as  possible 
discarded.  At  the  hospital  referred  to  above  (Chartres)  the  walls,  floor,  and 
ceiling  are  of  cement,  the  window  sashes  and  doors  are  of  iron,  the  tables 
and  shelves  for  instruments  are  of  glass  on  iron  supports,  and  the  operation 
table  itself  is  of  zinc  and  iron.  The  operation  room  at  the  Derbyshire 
General  Infirmary  has  the  walls  lined  with  marble  to  a  height  of  seven  feet, 
above  which  they  are  cement.  The  floor  is  of  marble  mosaic,  the  door  and 
windows  of  iron,  with  the  frames  flush  with  the  wall,  and  the  tops  to  the 
sink  and  lavatory  basins  of  glass.  In  fact,  so  far  as  the  structure  and  fittings 
of  the  room  are  concerned,  everything  should  minister  to  the  condition  of 
perfect  asepticism,  so  necessary  to  be  obtained. 

Immediately  adjoining  the  operation  theatre  there  should  be  a  surgeons' 
room,  a  room  for  the  administration  of  anaesthetics,  and,  if  possible,  a  small 
ward  for  the  reception  of  a  patient  whom  it  is  not  desirable  to  move  back  to 
the  general  ward  immediately  after  operation. 

Out-patient  Department. — Three  things  are  necessary  to  the  orderly 
working  of  a  large  out-patient  department :  (1)  a  spacious  and  well-ventilated 
waiting-hall,  where  patients  can  be  grouped  and  classified  according  to  their 
cases  ;  (2)  a  sufficient  number  of  consulting  rooms  readily  accessible  from 
the  waiting  room  ;  and  (3)  a  dispensary  with  small  waiting-room  attached, 
so  placed  that  patients  do  not  have  to  re-enter  the  main  waiting  hall  after 
they  leave  the  consulting  rooms.  The  whole  of  the  department  must  also 
be  on  one  floor  only,  and  entirely  detached  from  the  main  buildings  of 
the  hospital.  A  reference  to  the  plan  of  the  out-patients'  department  of  the 
Great  Northern  Central  Hospital  (fig.  134)  will  make  these  points  clear. 
The  entrances  are  separate  for  each  sex,  and  the  two  small  waiting-rooms 
are  arranged  just  within  each  entrance  for  new  patients  to  wait  their  turn  for 
registration.  Old  patients  pass  straight  into  the  large  waiting-hall,  where 
they  are  sorted  out  into  groups  according  to  their  cases. 

The  consulting-rooms  are  four  in  number,  and  to  each  is  attached  a 
smaller  room  for  examining  patients.  There  is  also  a  dark  room  for  ophthal- 
moscopic work.  After  a  patient  has  been  seen  by  a  medical  ofiicer  he  passes 
into  the  corridor  at  the  back,  and  thence  into  the  waiting-room  beyond,  where 
he  waits  his  turn  in  a  queue  for  getting  to  the  dispensary  window.  This 
may  be  taken  as  a  fair  example  of  an  out-patients'  department  in  a  mode- 
rate-sized hospital  with  no  medical  school  attached.  In  the  large  clinical 
hospitals  the  consulting-rooms  would  have  to  be  greatly  enlarged  in  order 
to  afford  space  for  the  students.  In  smaller  hospitals  a  less  number  of  con- 
sulting-rooms would  suffice. 

Mortuary. — It  is  of  even  greater  importance  that  the  mortuary  should  be 
a  detached  building  than  the  out-patients'  department,  but  it  does  happen 
that  in  very  crowded  situations  it  is  impossible  to  afford  room  for  a  detached 
building  at  a  sufficient  distance  from  the  ward  windows  ;  in  such  a  case  the 
mortuary  ought  certainly  to  be  relegated  to  the  top  of  the  building,  and 
communication    should  be  made  by  an   outside   staircase   and  lift.     The 


734 


HYGIENE 


mortuary  should  include,  besides  the  room  where  several  bodies  may  be  kept 
at  one  time,  a  small  chamber  where  one  body  at  a  time  can  be  viewed  by 
friends,  and  which  may  take  the  form  of  a  mortuary  chapel. 


KEITH.  D.YOVNG^ 
HENRY  HfJLC    ) 

/JRCHJTECTS. 


MEN 


l^FEET. 


Fig.  ia4. 

Attached  to  the  general  dead-house,  but  having  no  communication  with 
the  smaller  room,  should  be  the  jpost-mortem  room,  and  in  the  smaller  class 
of  hospitals  with  no  medical  schools  there  should  also  be  a  room  for  the 
pathologist  and  a  small  museum. 

The  post-mortem  room  must  be  top  hghted,  and  should  have  a  floor  of 
some  impervious  material,  made  to  fall  to  a  channel  under  the  table.  The 
walls  should  be  lined  with  glazed  bricks  or  tiles,  the  table  should  be  of  marble 


THE  DWELLING 


735 


on  an  iron  frame,  and  the  shelves  should  be  of  the  same  material.  A  large 
and  deep  sink  must  be  provided,  and  the  waste-pipe  therefrom  must  be  treated 
in  the  same  way  as  a  soil-pipe.  An  efficient  trap  should  be  fixed  immediately 
under  the  sink,  and  the  pipe  taken  out  through  the  wall  into  a  vertical  pipe, 
which  must  be  carried  up  to  its  full  diameter  as  a  ventilator. 

Examples  of  Hospital  Planning 

I.  Large  General  Hospital  luith  Medical  School,  University  Hospital, 
Halle,  Germany. — This  large  and  important  hospital  was  commenced  in  the 
year  1876  and  completed  in  1884.  It  consists  of  sixteen  separate  build- 
ings, thirteen  of  which  form  the  hospital  proper,  the  other  three  being 
devoted  to  teaching  purposes.  The  general  disposition  of  the  buildings  is 
shown  on  the  block  plan  (fig.  135). 

The  central  block,  a,  with  its  four  wings,  is  the  surgical  house.  The  central 
"building  is  two  storeys  in  height,  with  a  basement,  and  the  out-patients' 


HfJLLE  UNIVERSITY  HOSPITAL 


MaGDEBUftGER         STRaSSE. 


Pig.  135. 

department,  operation  room,  and  rooms  for  the  director  and  the  resident 
medical  staff.  On  the  upper  floor  are  also  some  small  wards  for  two,  three, 
and  four  patients  each.  The  wings  are  one  storey  only  in  height,  and  contain 
each  a  ward  for  twenty-four  beds,  with  duty  room,  nurses'  room,  lavatory, 
bathroom,  and  water-closets.  These  wings  are  raised  about  eight  feet  above 
the  ground,  and  the  part  under  the  wards  is  entirely  open.  At  the  ends, 
under  the  duty  room  and  the  other  ward  offices,  the  basement  is  utilised  for 
storage  purposes.  The  floor  space  per  bed  is  142  feet,  and  the  cubic  space 
2,210  feet.  The  beds  are  arranged  in  pairs  opposite  each  pier,  and  a  space 
of  about  ten  feet,  with  a  window,  intervenes  between  the  end  bed  on  each 
side  and  the  end  wall  of  the  ward.  The  floor  is  finished  with  terrazzo,  a 
mixture  of  small  pieces  of  marble  and  cement  ground  to  a  smooth  surface  and 
polished.  The  water-closets  are,  as  is  usual  in  Germany,  connected  with 
the  ward  by  an  ante-room  or  passage,  and  no  attempt  is  made  to  separate 
them  from  the  ward  air  by  means  of  cross-ventilated  lobbies.  The  walls  are 
formed  of  timber  framing,  filled  in  with  brickwork  and  covered  inside  with 
boarding.  On  the  south  side  of  each  ward  is  a  broad  verandah,  with  steps 
leading  down  into  the  garden. 

These  wards,  in  common  with  all  the  rest  of  the  buildings,  are  warmed 


736  IIYGIEXE 

by  steam,  the  pipes  for  eonveyin.q;  'uhicli  are  carried  round  the  walls  behind 
the  beds.  Ventilation  is  provided  for  in  summer  by  open  windows  and  a 
ventilating  lantern  on  the  apex  of  the  roof,  and  in  winter  by  an  underground 
flue  connected  with  the  furnace  shaft  of  the  boiler-house  for  carrying  oft"  the 
vitiated  air,  and  by  openings  in  the  outer  walls  of  the  ward  for  admitting 
fresh  air  below  the  steam  coils  and  pipes. 

The  two  buildings  B  and  c  are  respectively  the  kitchen  block  and  the 
engine-house.  The  kitchen  block  is  four  storeys  in  height,  and  contains, 
besides  the  kitchen  with  its  scullery,  larders,  and  other  appurtenances,  the 
laundry  and  bedrooms  and  day  rooms  for  servants  and  officers. 

The  engine' house  contains,  besides  the  boilers  and  machinery,  a  disinfec- 
tion house  fitted  with  a  steam-disinfection  apparatus. 

Block  D  contains  the  gynecological  department,  and  has  accommodation 
for  eighty  patients  in  wards  varying  in  size  from  one  to  six  beds  each.  Here 
are  also  rooms  for  students  and  medical  stafl:",  operation  room,  lecture  room, 
and  apartments  for  the  midwife. 

Block  E  is  the  director's  house. 

Block  F,  with  the  detached  blocks  G  G,  comprises  the  medical  department. 
The  central  block  with  its  two  wings  is  two  storeys  in  height,  besides  a  half- 
sunk  basement.  The  basement  floor  of  the  central  block  is  devoted  to  rooms 
for  porters  and  other  men  servants.  In  the  basement  of  the  wings  are  four 
wards  for  syphilitic  patients,  two  in  each  wing  ;  and  in  each  wing  a  room 
for  lunatic  patients,  with  a  padded  room  attached. 

The  ground  floor  of  the  central  block  contains  the  out-patients'  depart- 
ment, with  rooms  for  laryngoscopy,  electrical  apparatus,  and  for  examination 
of  patients,  a  large  lecture  hall,  and  rooms  for  the  director  and  assistants. 
The  upper  floor  contains  some  small  wards  for  children,  quarters  for  resident 
stafl',  registrar's  rooms,  and  library. 

In  each  wing  there  is  on  the  ground  floor  a  ward  for  twelve  beds,  a  smaller 
ward  for  three  beds,  and  two  private  wards  for  paying  patients  (one  bed  each). 
This  arrangement  is  repeated  on  the  first  floor. 

The  detached  blocks  G  G  are  very  similar  in  arrangement  to  but  smaller 
than  the  surgical  pavilions.  The  wards  are  for  sixteen  beds  only,  and  there  is 
in  addition  in  each  pavilion  a  separation  ward  for  one  bed.  These  pavilions 
are  raised  above  the  ground  about  3  feet ;  the  flooring  of  the  wards  is  of 
deal,  and  the  walls  are  of  brick  plastered  inside.  The  floor  space  is  135  feet, 
and  the  cubic  space  2,033  feet  per  bed. 

Blocks  H  I  are  two-storey  buildings,  described  as  '  extension  '  pavilions. 
They  contain  on  each  floor  a  ward  for  twelve  beds,  a  small  ward  for  two  beds, 
and  the  usual  offices.  These  pavilions  are  intended  for  medical  and  surgical 
cases  respectively. 

Block  L  is  a  one-storey  pavilion  divided  centrally  by  the  entrance,  duty 
room  and  nurses'  rooms,  and  contains  two  wards  for  twelve  beds  each,  one 
for  male,  the  other  for  female  cases,  and  is  used  for  isolation  purposes.  At 
each  end  is  a  separation  ward  for  one  bed.  The  floor  space  per  bed  is  128 
feet  and  cubic  space  1,925  feet. 

K  is  the  chapel. 

M  is  a  two-storey  building  \\dth  basement,  devoted  to  patients  suffering 
from  diseases  of  the  eye  and  ear.  The  basement  is  occupied  by  rooms  for 
the  porters  &c.  and  storerooms.  The  entrance  is  in  the  centre  on  the  north 
side  ;  the  wing  to  the  right  of  the  entrance  contains  the  eye  wards,  that  to 
the  left  the  ear  w^ards.  In  the  central  part  are  rooms  for  the  director  and 
assistants,  operation  theatre  and  lecture  hall,  and  nurses'  rooms.  The  wards 
are  arranged  for  six  beds  each. 


THE  DWELLING 


T61 


N  is  the  pathological  institute,  o  the  physiological  institute,  and  p  the 
anatomical  institute ;  b  is  the  icehouse,  and  q  a  building  in  which  the  sewage 
of  the  whole  hospital  is  disinfected  before  passing  into  the  town  sewers. 

The  buildings  occupy  a  site  of  some  eight  acres  in  extent. 

/JHTWERP  CIVIL  HOSPITfIL . 


NEV^      STREET. 


RUE  DES    IMfjeES. 


BILMB.YER  ^V/7/V  fllEL 

ARCHITECTS. 


'HftLFPLfIN  OF 
VENTJLfJTlNS  SHAFTS. 


plan  of  a  waed  pavilion, 
Fig.  136. 

Civil  Hospital,  Ankoerp. — This  hospital  (fig.  136)  is  the  largest  and  most 
complete  example  of  the  circular  ward  system  yet  erected,  and  it  is  also 
specially  interesting  in  having  been  the  first  instance  in  which  the  ckcular 
form  was  adopted. 

The  site  upon  which  the  hospital  stands  is  nearly  ten  acres  in  extent,  and 
is  bounded  on  all  four  sides  by  public  streets.  The  large  area  of  the  site 
enabled  the  buildings  to  be  disposed  in  such  a  fashion  that  the  space  between 
the  various  blocks  is  extremely  ample.  The  large  block  (a)  at  the  entrance 
in  the  Eue  des  Images  contains  the  director's  and  almoner's  residence,  porter's 

VOL.  I.  3  B 


738  HYGIENE 

lodge,  and  rooms  for  medical  students,  servants,  &c.  The  corridors  for  com- 
munication with  the  ward  pavilions  lead  oil  from  each  side  of  the  central 
block  of  the  front  building.  Proceeding  along  the  western  corridor,  the  small 
building  marked  B  contains  the  operation  room,  with  its  two  adjoining 
rooms  for  the  surgeons  and  surgical  appliances  and  two  wards  for  one  bed 
each.  The  corresponding  building  to  this,  c,  on  the  east  side,  contains  the 
mortuary  and  2^ost-inortcm  room,  with  workshops  below.  Separated  from  this 
by  a  small  enclosed  yard  is  a  coachhouse,  stable,  and  coachman's  dwelling. 

The  blocks  marked  d  are  the  ward  pavilions,  and  are  all  arranged  on  the 
same  plan.  ■  Each  pavilion  is  two  storeys  in  height,  and  has  cellars  under 
the  whole.  The  corridor  is  one  storey  only  between  the  pavilions,  with  a 
basement  which  serves  as  a  subway  for  communication  between  the  wards 
and  the  laundry,  and  also  for  access  to  the  ventilating  shafts  under  the 
wards.  On  the  ground  floor,  on  the  side  of  the  corridor  further  from  the 
ward,  is  the  main  staircase,  a  secondary  staircase  leading  to  the  roof,  a  lift 
for  patients,  a  separation  ward,  and  a  room  in  which  are  shoots  for  refuse 
and  for  dirty  Unen,  and  a  recess  in  which  the  pipes  for  water,  gas,  &c.,  are 
arranged  ;  on  the  other  side  of  the  corridor  are  two  separation  wards  for  one 
bed  each.  From  the  building  which  contains  all  the  above  accommodation 
a  covered-in  bridge  leads  to  the  main  ward.  This  bridge,  hke  those  that 
connect  the  ward  with  the  water-closets,  is  only  about  half  the  height  of  the 
ward  itself.  By  this  means  the  movement  of  air  around  the  ward  is  much 
freer  than  it  would  be  if  the  bridges  of  communication  were  carried  up  the 
whole  height  of  each  storey.  The  wards  are  Gl  ft.  6  in.  in  diameter,  and 
about  17  ft.  in  height.  They  each  contain  twenty  beds,  at  which  number 
the  floor  space  per  bed  is  148*5  ft.  and  the  cubic  space  2524"5  ft.  The 
actual  number  of  beds,  however,  in  each  of  these  wards  is  twenty-four, 
which  reduces  the  floor  area  to  123"7  ft.  and  the  cubic  space  to  2103-7  ft.  In 
the  centre  of  each  ward  is  an  octagonal  space  partitioned  off  with  a  glass 
screen  some  8  ft.  high,  and  used  as  a  Sister's  room.  The  intention  of  this  room 
appears  to  be  that  the  Sister  should  use  it  as  a  sitting-room  when  on  duty,  and 
that  the  various  apphances  and  di'ugs  used  in  the  wards  should  be  kept  there. 
The  exact  centre  of  the  ward  is  occupied  by  the  exhaust  shaft  for  foul  air, 
while  at  each  of  the  right  angles  of  the  nurses'  room  is  a  shaft  for  the  supply 
of  warm  air.  The  floors  of  the  wards  are  laid  with  oak  boards,  wax  polished, 
and  the  walls  are  plastered  with  a  composition  of  gypsum  and  Hme.  The 
warming  is  effected  by  means  of  hot  air,  which  is  forced  into  the  wards  by 
a  fan  in  the  engine-house  passing  in  its  way  over  coils  of  steam  pipes,  and 
can  be  discharged  either  at  the  floor  or  the  ceiling  level  as  desired.  The 
central  shaft,  already  referred  to,  is  provided  with  steam  coils  at  its  base,  in 
order  to  warm  the  air  and,  by  its  expansion,  produce  an  up  current.  The 
separation  wards  are  also  warmed  and  ventilated  on  the  same  system. 

The  small  projecting  block  to  each  pavihon  contains  a  tisanerie  or 
tea  kitchen,  bathroom,  lavatory,  two  water-closets,  and  two  sinks. 

Block  E  is  the  chapel,  which  is  connected  by  an  open  passage  with  the 
main  corridor  of  communication  ;  the  flat  roof  over  this  passage  affords 
means  of  communication  between  the  upper  floor  of  the  wards  and  the 
gallery  of  the  chapel.  Block  f  contains  the  kitchen  offices  and  the  dis- 
pensary and  drug  store ;  also  dining  rooms  for  male  and  female  con- 
valescents, attendants,  and  servants.  Block  g  is  the  house  for  the  Sisters  of 
Mercy,  with  the  linen  store  and  lint  store.  Block  h  at  the  further  end  is 
the  bathhouse.  Here,  as  is  common  in  large  Continental  hospitals,  are, 
besides  ordinary  baths  for  both  sexes,  a  Turkish  bath,  shower  bath,  two 
vapour  baths,  and  two  sulphur  baths.     The  detached  block,  J,  at  the  extreme 


THE  DWELLING 


739 


north  of  the  site,  is  the  laundry,  and  washhouse,  used  also  for  the  washing 
of  all  the  other  hospitals  in  charge  of  the  communal  authorities  of  Antwerp. 
A  '  Barrack '  or  Hut  Hospital.  The  Mtmicipal  Hospital  at  Moabit, 
Berlin. — This  hospital  (fig.  137)  was  erected  in  1872  by  the  city  authorities 
of  Berlin  for  the  purposes  of  an  epidemic,  but  it  has  since  been  utilised  for 
the  reception  of  patients  suffering  from  all  kinds  of  diseases,  including  such 
infectious  fevers  as  typhus  and  small-pox.  The  site  is  a  long  narrow  parallelo- 
gram of  about  nineteen  acres  in  extent,  and  having  its  longer  axis  north  and 
south.  At  the  south  end  are  situated  the  administration  buildings  :  A,  porter's 
lodge ;  B,  offices  and  residence  for  staff ;  o,  kitchen  ;  d,  engine  and  boiler 
house ;  b,  disinfection  house ;  f,  laundry ;  g,  g  g,  stables  and  stores  ;  h,  fire 
brigade  depot ;  i,  ice-house  ;  j,  isolation  wards. 


J=>Lffrf    OF  a  WARD  BLOCK. 


UNEN. 

LRVflTf  C. 

( 

nnnnnnnnnnnnnn-' 

\ 

'  DUTY 

UULIuuUUUUULIUulJ-, 

J°A7. 


CITY  BRRRRCK  LflZ/JRETH 
MO  ABIT    BERLIN. 


■^> 


IttaURERnEISTER       STRHUSS  i 


iiniiiiiiiii/ 


Fig.  137. 


The  ward  pavihons,  twenty-four  in  number,  are  ranged  round  both  sides 
of  the  site.  Each  paviHon  is  entirely  isolated  from  the  others,  and  the  space 
of  about  56  ft.  intervenes  between.  The  pavihons  are  all  of  one  storey,  are 
constructed  of  timber  framing  filled  in  with  stone,  and  lined  on  the  inside 
with  painted  boards.  The  floors  are  composed  of  a  species  of  concrete 
(beton),  finished  with  a  smooth  surface  of  cement.  The  roof  projects  about 
6  ft.  on  each  side,  and  is  formed  of  a  double  layer  of  planks  grooved  together, 
painted  on  the  inner  side,  and  on  the  upper  surface  covered  with  asphalte. 
At  the  entrance  of  each  pavihon  is  a  nurses'  room,  duty  room,  room  for  the 
temporary  storage  of  dirty  linen,  and  a  bathroom  and  a  water-closet ;  the 
two  latter  are  entered  directly  from  the  ward,  and  in  the  water-closet  are  two 
apparatus.  Each  ward  contains  twenty-eight  beds,  with  a  floor  space  of  about 
69  ft.  per  bed  and  a  cubic  space  of  864  ft.     At  the  apex  of  the  roof  is  a  long 

3b  2 


740 


HYGIENE 


BLOCK      PLm. 

'P?  °  'P  ^°  ^° ^  ?°  ^°  ?°  §"  ^,°FEEr 


ventilator,  and  at  the  end  of  each  ward  are  large  folding  doors,  which  are 
constantly  open  in  summer.  In  the  extreme  north-west  corner  of  the  site 
are  the  mortuary  (n),  waiting  hall  (o),  and  shed  (p)  for  burning  clothing 
&c.  which  has  been  exposed  to  infection. 

A  Provincial  Hospital  with  no  Medical  School. — Lincoln  County  Hospital 
(fig.  138),  designed  by  Mi-.  Alexander  Graham,  has  been  selected  as  a  good 

LJtSQQLNiJim  COUNTy  HOSPITAL.  example    of   a    pro- 

i  vincial     hospital     of 

average  size.  It  has 
accommodation  for 
105  beds.  The  gene- 
ral plan  is  in  the  form 
of  an  H,  with  pro- 
jecting buildings  on 
both  sides  of  the  cross 
stroke.  The  upright 
strokes  are  occupied 
by  the  wards,  which 
are  two  storeys  in 
height.  The  ground 
floor  of  that  half  of 
the  western  wing 
which  lies  to  the 
south  of  the  cross 
stroke  of  the  H  is 
devoted  to  the  out- 
patients' depart- 
ment, which  is  thus 
placed  in  very  inti- 
mate connection  with 
the  wards,  the  only 
serious  blot  on  an 
otherwise  excellent 
plan.  The  buildings 
projecting  at  front 
and  back  of  the  cross 
stroke  contain  the  ad- 
ministration offices, 
the  operation  room, 
accident  room,  and  some  small  wards  for  eye  cases.  The  large  wards  are 
each  88  ft.  by  26  ft.  6  in.,  those  on  the  ground  floor  being  14  ft.  and  those 
on  the  first  floor  16  ft.  high.  The  beds  are  arranged  in  pairs  between  each 
window.  The  floor  space  per  bed  is  115*2  ft.,  and  the  cubic  space  1613-7  ft. 
on  the  ground  floor  and  1844-3  ft.  on  the  upper  floor. 

Toilet  System.  Municipal  Hospital,  St.  Denis. — The  system  of  hospital 
construction  of  which  the  new  Municipal  Hospital  at  St.  Denis  is  an  example 
is  the  invention  of  M.  Toilet,  an  engineer  of  eminence. 

The  special  pecuharity  of  the  system  is  the  form  -\\  liich  M.  Toilet  adopts 
as  the  section  of  his  wards.  A  transverse  section  of  a  ward  is  in  the  form 
of  a  Gothic  pointed  arch.  The  grounds  upon  which  this  form  is  adopted 
are  that  it  is  said  to  lend  itself  more  readily  to  efficient  ventilation,  to 
prevent  stagnation  of  air,  and  to  present  the  minimum  of  surface  for  absorp- 
tion. Other  characteristics  of  M.  Toilet's  plans  are  the  limitation  of  all 
■wards  to  buildings  of  one  storey  only,  the  complete  isolation  of  the  several 


PL/Jfi  OF  f>  W^RD 


lo  5  9      ip     2p     3.0    1*9     ^P 
U  T 1 1 ±^ 1 L 

Fig.  1st*. 


f_L°  FEET, 


THE  DWELLING 


741 


paviKons  one  from  the  other,  the  adoption  as  far  as  possible  of  non-absorbent 
surfaces,  and  the  avoidance  of  all  angles,  the  use  of  fire-resisting  materials, 
the  adoption  of  natural  means  of  ventilation,  and  the  use  of  balconies  and 
open  space  beneath  the  wards.  Obviously  none  of  the  foregoing  are  the 
invention  or  the  speciality  of  M.  Toilet ;  but  the  thoroughness  and  skill  with 
which  he  has  recognised  the  advantages  of  and  combined  all  these  features 
are  noteworthy  indications  of  the  progress  of  hospital  hygiene  in  France. 


PLffn  OF  ONE  y^'RRD  BLOCK. 


Fig.  loO. — Hospital  of  St.  Denis. 


The  pointed-arch  form  adopted  by  M.  Toilet  necessitates  the  provision  of 
a  very  much  larger  amount  of  cubic  space  per  bed  than  is  usual  or  under 
ordinary  conditions  necessary.  But  as  an  essential  part  of  the  system  is  that 
the  outlet  for  foul  air  is  at  the  apex  of  the  roof,  the  ordinary  rule  by  which 
any  access  of  height  over  12  feet  is  disregarded  would  seem  not  to  be  appli- 
cable in  this  case.  It  must,  however,  render  necessary  greatly  increased 
warming  power. 

Whatever  may  be  the  special  merits  of  the  pointed  arch,  of  this  there  can 
be  no  doubt,  that  the  general  arrangements  and  the  structural  details  of  the 
hospitals  designed  on  this  principle  are  immensely  in  advance  of  anything 
that  had  preceded  them  in  France. 


742  HYGIENE 

The  Municipal  Hospital  at  St.  Denis  was  designed  by  M.  Laynaud^ 
architect,  and,  in  addition  to  its  being  a  good  example  of  the  Toilet  system,  is 
in  itself  interesting  as  a  type  of  a  modern  French  provincial  hospital. 

The  site  is  of  an  irregular  shape,  and  situated  just  outside  the  old  town 
of  St.  Denis,  close  to  the  glacis  of  the  Fort  de  I'Est.  Its  situation  ensures 
that  it  will  never  be  surrounded  by  buildings. 

The  buildings  (see  fig.  139)  are  arranged  m  detached  blocks,  there  being 
no  covered  communication  between  them,  except  in  the  case  of  two  wards  for 
the  same  class  of  diseases  being  coupled. 

The  building  to  the  east  of  the  entrance  contains  the  boardroom  and' 
ofiBces,  and  the  kitchen  offices,  stores,  &c. ;  that  to  the  west  contains  the 
residences  for  staff  and  the  dispensary.  The  two  buildings  to  the  east  and 
west  of  the  above-mentioned  two  blocks  are  for  aged  women  and  men 
respectively.     These  form  the  Hospice. 

Of  the  five  blocks  forming  the  central  row  of  buildings,  the  two  at  the 
extreme  ends  are  the  medical  wards,  those  to  the  east  being  for  women,  those 
to  the  west  for  men.  Each  block  contains  two  wards  for  sixteen  beds  each 
and  two  small  wards  for  two  children  each.  In  the  centre  is  a  day  room,, 
with  duty  room,  nurses'  room,  and  the  usual  offices.  It  is  noteworthy  that 
here,  as  in  all  hospitals  constructed  on  M.  Toilet's  system,  the  water-closets  are 
separated  from  the  wards  by  cross-ventilated  lobbies.  The  three  pavilions 
in  the  centre  are  for  surgical  cases.  Attached  to  each  medical  pavilion  is  a 
bathhouse,  in  which  are,  besides  two  ordinary  baths,  the  vapour  and  douche 
bath  usual  in  Continental  hospitals.  Beyond  the  bathhouse  on  the  male 
side  is  the  laundry.  The  two  small  blocks  north  of  the  surgical  pavilions 
are  for  the  isolation  of  infectious  diseases  ;  behmd  them  is  the  chapel,  and  at 
the  apex  of  the  site  is  the  mortuary. 

The  large  wards  each  contain  sixteen  patients.  The  floor  space  per  bed 
is  about  112  ft.  and  the  cubic  space  2,457  ft.  The  ends  of  the  wards  are 
rounded  off  at  a  large  radius,  and  in  the  centre  of  the  curve  at  each  angle  of 
the  ward  is  a  small  window.  The  wards  are  raised  upon  piers  above  an  open 
basement  storey  which  is  used  as  a  subway  of  communication  from  one  ward 
to  the  other,  and  in  which  the  caloriferes  for  warming  the  wards  are  placed. 

A  Workhouse  Hosiyital. — Perhaps  m  no  department  of  hospital  con- 
struction has  so  great  an  advance  been  made  during  the  last  twenty  years 
as  in  the  infirmaries  belonging  to  large  parishes  or  unions.  From  being 
a  department  of  a  workhouse,  and  provided  with  accommodation  often  of 
the  most  unsuitable  nature,  the  Poor-law  infirmary  has  now  come  to  be 
recognised  as  a  hospital  needing  properly  arranged  buildings  and  a  well- 
equipped  and  properly  trained  staff.  The  large  institutions  built  by  several 
metropolitan  and  provincial  unions,  as,  for  instance,  St.  George's  Infirmary, 
Fulham  Eoad ;  St.  Marylebone,  Notting  Hill ;  Manchester  Workhouse  In- 
firmary, and  Chorlton  Union  Infirmary,  are  examples  of  the  improvement 
that  has  taken  place  in  recent  years.  Many  of  the  buildings  in  question 
present  obvious  defects  of  arrangement,  such  as  a  too  close  proximity  of 
buildings  one  to  another  and  the  piling  one  over  another  of  many  storeys 
of  wards.  These,  however,  in  \-iew  of  the  very  great  improvement  in  general 
arrangements,  are  defects  of  minor  importance. 

In  the  building  illustrated  (fig.  140)  these  defects  appear  to  a  less  degree 
than  in  many  others.  The  site  is  a  fairly  ample  one,  and  the  buildings  are  well 
separated.  The  plan  is  a  very  simple  one,  and  consists  of  four  ward  pavilions, 
each  three  storeys  high,  a  central  administrative  block,  a  detached  wash- 
house,  and  a  mortuary.  The  ward  pavilions  are  connected  with  each  other 
and  with  the  administrative  block  by  a  corridor  which  is  enclosed  at  the 


THE  DWELLING 


743 


sides  on  the  ground  floor,  but  is  an  open  arcade  on  the  first  floor.     At  the 
entrance  is  a  porter's  lodge  and  a  small  block  of  receiving  wards. 

Cottage  Hosiyltals. — Since  the  establishment  of  the  first  cottage  hospital 
at  Cranleigh  by  Mr.  Napper,  in  1859,  the  value  of  these  institutions  has 
been  increasingly  recognised,  and  numberless  hospitals  of  varying  sizes 
and  of  different  degrees  of  good  and  bad  arrangement  have  been  established 
throughout  the  country.  The  Cranleigh  Hospital  is  a  very  old  cottage,  and 


HEMiY.MRVIS&SOII. 


EflST     DULWICH       GROl/E. 


PLfJN    OF  fl    WffRO    BLOCK. 


Bf)ixor\ 


10    5     <?  _   .W        'Sa        30       ^        So       60         70         80        90        ioopppy 

FiG.  140. — St.  Saviour's  Union  Infirmary,  Champion  Hill. 


the  cost  of  its  adaptation  to  its  present  purposes  was  only  about  501.  Many 
hospitals  of  recent  years  have  been  built  as  cottage  hospitals,  which  can  in 
no  sense  of  the  term  be  called  cottages.  They  are,  in  fact,  small  pavilion 
hospitals,  and  are  planned  on  the  lines  of  the  larger  general  hospitals.  A 
cottage  hospital,  then,  should  be,  as  its  name  implies,  a  building  of  the 
cottage  type,  with  its  special  needs  as  a  hospital  carefully  kept  in  view. 
Economy  of  working  is  an  important  point  to  be  observed,  as  it  is  often 
difficult  to  obtain  the  funds  necessary  for  maintaining  a  village  hospital. 
The  accommodation  for  patients  in  a  true  '  cottage  '  hospital  will  vary  from 
four  to  ten  or  twelve,  and  the  staff  will  comprise  a  nurse  and  one  or  two 


744  HYGIENE 

servants.  There  should  be  a  room  where  operations  can  be  performed,  which 
can  also  be  used  when  required  for  committee  meetings.  The  other  rooms 
required  are  a  sitting-room  and  a  bedroom  for  the  nurse,  a  bedroom  for 
servants,  and  the  usual  domestic  offices  for  a  small  household. 

It  is  scarcely  necessary  to  say  that  the  same  scrupulous  attention  to  good 
sanitary  arrangements  are  as  essential  in  a  village  hospital  for  four  beds  as  in 
a  town  hospital  for  400,  and  the  mistake  so  often  made  of  neglecting  to 
properly  isolate  the  water-closets  and  sinks  from  the  wards  is  as  inexcusable 
in  a  cottage  hospital  as  it  would  be  in  one  of  the  largest  type. 

II.   Special  Hospitals 

Not  for  Infcctmcs  Diseases. — In  this  class  of  hospitals  are  included  a  great 
number  of  institutions  which  possess  no  special  features  of  interest  apart 
from  the  conditions  which  pertain  to  general  hospitals.  Such  hospitals  as 
those  for  diseases  of  the  ear  and  throat,  cancer,  and  incurables  require 
practically  the  same  arrangements  as  to  details  and  hygiene  as  hava  been 
described  under  the  head  of  General  Hospitals. 

Ophthalmic  hospitals  require  to  be  constructed  with  special  reference  to 
the  condition  of  blindness  or  semi-blindness  of  the  patients.  The  careful 
avoidance  of  salient  angles  in  positions  where  a  patient  would  be  liable  to 
run  against  them  and  possibly  injure  an  eye  beyond  repair,  and  the  provision 
of  handrails  on  both  sides  of  all  staircases,  are  points  that  require  careful 
attention.  It  is  also  most  desirable  to  abolish  open  fireplaces  in  all  wards 
and  rooms  used  by  patients,  and  to  warm  by  means  of  hot-water  pipes,  with 
a  due  provision  for  the  supply  of  fresh  air,  the  flickering  light  of  an  open 
fire  being  very  trying  and  sometimes  injurious  to  diseased  eyes.  The  lighting 
of  the  consulting  rooms  and  the  ventilation  of  the  ophthalmoscope  rooms  are 
points  that  require  careful  attention.  The  hghting  also  of  the  operation  room 
is  important ;  the  top  light  required  in  an  operation  room  for  a  general 
hospital  is  for  eye  operations  wholly  useless.  The  window  should  be  entirely 
vertical,  and  its  aspect  should  by  preference  be  towards  the  north. 

Hospitals  for  children  are  practically  general  hospitals  with  a  limitation 
to  the  age  of  the  patients.  Special  attention  must  be  paid  to  the  means  for 
isolating  infectious  cases,  as  such  diseases  as  measles,  whooping  cough,  and 
scarlatina  are  much  more  likely  to  arise  in  a  children's  hospital  than  in  one 
for  adults.  The  '  visiting  day  '  is  undoubtedly  the  chief,  if  not  the  only,  cause 
of  the  evil ;  but  inasmuch  as  it  would  be  a  practical  impossibility  to  abolish 
'  visiting,'  the  only  thing  that  can  be  done  to  minimise  the  evil  is  to  provide 
efficient  means  of  isolation.  An  isolation  room  must  also  be  provided  in  the 
out-patients'  department  for  promptly  separating  any  child  discovered  to  be 
suffering  from  an  infectious  disease. 

For  consumption  hospitals  special  arrangements  are  necessary  for  the 
warming  and  ventilation,  in  order  that,  while  a  copious  supply  of  fresh  air  is 
maintained,  the  temperature  of  the  incoming  air  may  be  uniformly  kept  at 
such  a  point  as  will  not  be  injurious  to  the  lungs  of  the  patients.  Large 
wards  are  inadvisable  in  a  hospital  for  chest  diseases,  and  more  day  room 
space  is  also  required  than  in  a  general  hospital,  as  so  large  a  proportion  of 
the  patients  are  able  to  leave  their  beds  in  the  daytime. 

Convalescent  hospitals,  being  intended  for  patients  who,  while  they  have 
recovered  from  some  acute  illness,  yet  need  pure  air  and  rest  to  enable  them 
to  recover  their  strength,  are  more  properly  homes  than  hospitals.  While 
they  require  that  every  detail  of  sanitation  should  be  as  carefully  looked  after 
as  in  any  other  hospital,  there  are  no  special  features  that  need  be  further 
referred  to  here. 


THE  DWELLING  745 

Lying-in  hospitals,  though  not  relatively  a  very  numerous  class,  have 
yet  suffered  a  notoriety  beyond  all  others  for  persistent  and  excessive 
mortality.  Formerly  it  was  the  custom  to  set  apart  certain  wards  in  all 
general  hospitals  for  lying-in  cases,  and  in  France  this  custom  still  exists  in 
most  of  the  large  general  hospitals.  The  evils  which  this  system  produced 
were  first  specially  noticed  in  regard  to  the  Hotel  Dieu  at  Paris  towards  the 
end  of  the  last  century.  Later  on  the  excessive  mortality  incident  on 
parturient  women  at  the  great  Maternity  Hospital  of  Paris  attracted  the 
attention  of  the  medical  world,  and  in  1873-75  an  enquiry  conducted  by 
M.  Lefort  resulted  in  the  following  facts  : — 

Deaths 

(1)  Deliveries  in  general  hospitals  .        .        .        .        .        .     1  in    24 

(2)  „  special        „ 1  „     32 

(3)  „         at  home 1  „  528 

(4)  „        in  houses  of  '  sages-femmes  ' 1  „  200  ' 

In  London,  though  the  lying-in  hospitals  are  comparatively  small  and 
few  in  number,  the  record  of  mortahty  has  been  until  recently  very  heavy. 
The  largest  and  most  important  lying-in  hospital  in  the  United  Kingdom 
is  the  Eotunda  Hospital  at  Dublin  ;  but  even  in  this  the  average  death-rate  is 
stated  in  the  report  of  Dr.  Bristowe  and  Mr.  Holmes  as  between  one  and  two 
per  cent.,  whilst  the  death-rate  among  women  confined  in  their  own  homes 
is  put  by  the  same  authorities  at  "3  or  even  '2  per  cent.  The  Eeport  of 
the  Committee  on  Cubic  Space  in  the  Metropolitan  Workhouses  (appointed  by 
the  President  of  the  Poor-law  Board  in  1866)  records  the  remarkable  fact 
that  the  mortality  amongst  lying-in  women  in  workhouses  was  six  times  less 
than  that  in  the  largest  lying-in  institution  in  the  metropolis,  viz.  Queen 
Charlotte's  Hospital. 

The  exceptional  immunity  from  disease  enjoyed  by  the  patients  in  the 
lying-in  wards  of  workhouses  was  due  in  the  main  to  the  fact  that  separate 
labour  rooms  are  commonly  provided  in  those  institutions  and  that  each 
parturient  woman  was  isolated  for  a  time  during  and  after  deHvery.  And  it 
is  equally  certain  that  the  excessive  mortality  so  persistently  incident  on 
lying-in  hospitals  both  in  this  country  and  abroad  was  due  to  a  great  extent 
to  the  absence  of  any  means  of  isolation. 

A  lying-in  hospital,  then,  should  be  arranged  with  small  rooms  and  not  with 
large  wards.  Each  patient  should  be  kept  in  a  separate  room  for  a  certain 
definite  time  (usually  six  days)  after  confinement,  and  any  case  of  fever 
arising  in  the  hospital  should  be  promptly  removed  to  a  ward  absolutely 
isolated  from  the  rest  of  the  building. 

Hospitals  for  Infectious  Diseases — In  all  matters  that  concern  the  ques- 
tion of  structural  hygiene  the  class  of  hospitals  now  to  be  discussed  are  in  no 
degree  different  from  other  institutions  of  the  kind.  The  same  scrupulous 
attention  to  good  ventilation,  lighting,  and  all  the  various  details  which  con- 
duce to  cleanliness  and  a  healthy  condition  are  equally  necessary  to  all  hos- 
pitals. But  in  the  case  of  hospitals  for  infectious  diseases  there  are  certain 
points  of  arrangement  and  certain  requirements  which  are  special  to  the 
class  and  need  to  be  carefully  attended  to. 

At  the  outset  it  is  needful  to  have  a  clear  understanding  of  the  purpose 
and  objects  of  a  hospital  for  infectious  disease ;  and  it  may  be  well  here  to 
point  out  that,  unlike  the  great  body  of  general  and  special  hospitals,  most 
hospitals  for  infectious  disease  are  pubhc  buildings  provided  and  supported  by 
the  rates,  and  are  in  no  sense  charitable  institutions. 

'  These  figures  are  taken  from  Hospital  Construction  and  Management.  Mouat  & 
Snell. 


746 


HYGIENE 


The  duty  of  pro\ading  hospital  accommoclation  for  infectious  fever  has 
been  placed  by  the  Legislature  on  the  various  urban  and  rural  sanitary 
authorities,  in  order  that  those  bodies  may  be  enabled  by  timely  provision  of 
suitable  buildings  to  isolate  without  delay  any  case  of  an  infectious  fever 
arising  within  their  jurisdiction.  It  is  this  point  of  isolation  which  marks 
the  main  difference  between  a  hospital  for  infectious  disease  and  one  of  the 


CU>se  -fyice  6  rg'ySi^i^,_ 


Fig.  141. 

charitable  class.  In  the  former  the  patient  is  received,  not  primarily  for  his 
own  sake,  but  for  the  sake  of  others,  in  order  to  prevent  him  from  becoming 
a  source  of  danger  to  the  community.  In  the  latter  the  predominant  object 
is  the  good  of  the  patient  himself. 

A  hospital  for  infectious  disease,  therefore,  is  essentially  a  place  for  isola- 
tion, a  means  of  defence  against  the  spread  of  infectious  disease,  an  important 
weapon  with  which  to  ward  off  epidemics.  In  order,  therefore,  to  be  of  any 
value  it  is  clear  that  the  weapon  must  be  ready  to  hand  at  any  moment — 
must  be,  in  fact,  prepared  and  in  working  order  beforehand,  and  not  taken  in 
hand  when  the  disease  has  already  made  its  appearance. 

'  It  cannot  be  too  clearly  understood  that  an  isolation  hospital,  to  fulfil 
its  proper  purpose  of  sanitary  defence,  ought  to  be  in  readiness  beforehand. 
During  the  progress  of  an  epidemic  it  is  of  Uttle  avail  to  set  about  hospital 
construction.  The  mischief  of  allowing  infection  to  spread  from  first  cases 
will  already  have  been  done,  and  this  mischief  cannot  be  repaired.  Thus, 
hospitals  provided  during  an  epidemic  are  mainly  of  advantage  to  particular 
patients  ;  they  have  little  effect  in  staying  the  further  spread  of  infection. 
Moreover,  hospitals  provided  under  such  circumstances,  to  be  of  any  use, 
must  be  large  and  costly,  and  their  construction  can  seldom  be  of  a  kind 
that  is  suited  in  after  times  for  the  isolation  requirements  of  their  districts.'  ^ 

'  Meviorandum  on  the  Prvvision  of  Isolation  Hospital  Accommodation  by  Local 
Sanitary  Authorities,  Local  Government  Board,  Medical  Department. 


THE  DWELLING  lil 

Hospitals  erected  under  pressure  of  an  epidemic  are  of  necessity  hurriedly 
conceived  and  too  hastily  executed  ;  they  frequently  are  ready  for  patients 
only  when  there  are  no  longer  any  patients  to  be  received,  and,  as  pointed 
out  in  the  paragraph  quoted  above,  they  commonly  prove  of  little  or  no  service 
as  permanent  buildings. 

The  extent  of  hospital  accommodation  which  it  is  necessary  or  desirable 
to  provide  must  depend  upon  the  population  and  other  conditions  peculiar  to 
the  district  it  has  to  serve.  Whatever  may  be  the  amount  of  accommodation 
to  be  provided,  however,  the  general  principles  of  arrangement  will  remain 
the  same. 

The  simplest  type  of  isolation  hospital  (fig.  141)  must  comprise  three 
separate  buildings  :  1,  the  administration  block  ;  2,  a  block  for  patients  ;  and 
3,  the  washhouse,  mortuary,  and  disinfection  house  block.  These  three 
buildings  may  be  regarded  as  the  nucleus  or  irreducible  minimum  of  an 
isolation  hospital. 

The  administration  block  in  its  simplest  form  may  comprise  accommoda- 
tion for  a  caretaker,  kitchen  offices,  and  two  or  three  rooms  for  nurses  ;  or  it 
may  be  simply  a  cottage  containing  a  living  room  and  two  or  three  bedrooms 
for  the  caretaker  with  the  kitchen  offices — such  a  building  as  that  shown  on 
the  plan  issued  by  the  Local  Government  Board,  and  which  accompanies  the 
memorandum  on  isolation  hospital  accommodation  quoted  above. 

The  ward  block  shown  on  the  same  plan  provides  accommodation  for 
two  patients  of  each  sex,  with  two  nurses'  ante-rooms  on  the  ground  floor  and 
their  bedrooms  above.  The  third  block  contains  a  washhouse,  mortuary,  and 
a  small  disinfectmg  chamber.  It  will  be  obvious  that  such  a  hospital  pro- 
vides the  smallest  possible  amount  of  accommodation  and  contemplates  the 
reception  of  patients  suffering  from  one  disease  only. 

The  next  step  in  advance  of  this  is  to  enlarge  the  ward  block  by  the 
addition  of  one  or  more  rooms  for  patients  to  each  section.  It  then  be- 
comes the  typical  isolation  block  in  which  patients  of  each  sex,  and  suffering 
from  two  distinct  diseases,  can  be  treated.  This  block  is  the  most  impor- 
tant one,  and  whatever  else  is  omitted  this  must  always  be  provided.  For, 
take  the  case  of  a  hospital  consisting  of  a  single  ward  block,  containing  two 
large  wards  with  a  common  entrance,  ward,  kitchen,  &c.  A  single  patient 
suffering  from,  say,  scarlatina  placed  in  one  of  these  wards  renders  the  ad- 
mission of  patients  with  any  other  disease  an  impossibility.  If,  on  the  other 
hand,  the  ward  block  be  arranged  in  two  distmct  sections  as  in  the  model 
plan  (see  fig.  142),  there  is  always  provision  for  at  least  two  diseases ;  possibly, 
thanks  to  the  verandah  arrangement,  for  more  than  two. 

Every  hospital,  then,  must  possess,  in  addition  to  the  administration  offices 
and  the  washhouse,  mortuary,  &c.,  an  isolation  block  ;  and  this  block  should 
always  be  the  first  consideration.  The  immense  importance  of  this  isolation 
block  cannot  be  too  strongly  urged.  Cases  have  occurred  over  and  over 
again  of  a  patient  supposed  to  be  suffering  from  an  infectious  fever  being 
received  into  a  hospital  and  placed  in  a  ward  along  with  other  patients,  the 
nature  of  whose  disease  was  midoubted,  and  of  the  patient  in  question  being 
found  not  to  be  suffering  from  any  infectious  disease  whatever.  This  patient 
has  then  been,  notwithstanding  all  precautions,  removed,  and  again  ad- 
mitted to  the  same  ward  with  the  particular  disease  fully  developed,  and 
which  had  been  contracted  during  his  short  previous  stay  in  the  ward.  Such 
a  case  may  at  any  time  occur  and  will  occur  unless  isolation  hospitals  are 
what  they  profess  to  be,  and  are  provided  with  proper  isolation  wards  into 
which  doubtful  cases  can  be  admitted.  An  isolation  hospital  utterly  fails  ia 
its  purpose  if  it  becomes  the  means  of  propagating  disease  to  healthy  persons^ 


748 


HYGIENE 


tensive 

suitable 

matron 


In  addition  to  this 
there  should  be  a  ward 
pavilion,  or  pavilions, 
modelled  on  the  plan 
issued  by  the  Local  Go- 
vernment Board  and 
containing  from  six  to 
as  many  as  twenty  beds. 
The  latter  number  will 
only  occur  in  very  large 
hospitals,  and  large 
hospitals  for  infectious 
diseases  are  not  very 
desirable.  The  simplest 
form  of  the  ward  pavi- 
lion consists  of  two 
wards  with  a  nurses' 
duty  room  intervening ; 
also  a  linen  store,  small 
larder,  and  space  for 
movable  bath,  and  for 
each  ward  its  water- 
closet  and  sink  room. 
Such  a  pavilion  is  of 
course  intended  for  pa- 
tients of  both  sexes. 
In  large  hospitals  the 
pavilions  for  each  sex 
may  with  advantage  be 
separated,  and  it  will 
be  of  further  advantage 
to  provide  one  or  more 
separation  wards  for 
one  bed  each  in  each 
pavilion.  The  space  for 
movable  bath  will  de- 
velop into  a  bathroom 
and  should  be  so  ar- 
ranged that  a  patient 
on  being  discharged 
may  step  from  the  bath- 
room into  the  open  air. 
A  day  room  for  conva- 
lescent patients  is  also  a 
very  desirable  addition 
where  it  can  be  ar- 
ranged. 

The    administration 
buildings   for    a    large 
hospital  will  need  to  be 
on   a    much   more   ex- 
scale  than  the  simple  caretaker's  house,  with  bedrooms  for  nurses 
for  a  hospital  for  some  twenty  or  thirty  beds.    Apartments  for  the 
and  one  or  two  resident  medical  officers  will  have  to  be  provided, 


(0 
o 

lu 
ta 

z 

ui 

H 

DC 

2 


z 

0. 


THE  DWELLING  749 

also  rooms  for  the  steward  and  storerooms  of  a  size  proportionate  to 
the  extent  of  the  hospital.  Day  rooms  for  nurses  and  servants  will  also  be 
required,  and  ample  bathing  arrangements  for  all  the  staff  are  necessary. 

The  mortuary  building,  instead  of  being  only  a  single  room  which  has  to 
serve  the  purpose  both  of  mortuary  and  post-mortem  room,  will  contain  a 
properly  appointed  j^ost-mortem  room,  a  mortuary  chamber  provided  with  a 
glass  screen  to  separate  the  bodies  from  the  friends  who  come  to  see  them, 
and  a  small  waiting  room. 

The  laundry,  besides  being  increased  in  scale,  should  in  large  hospitals  be 
divided  into  two  complete  laundries,  one  being  for  the  patients'  clothes,  the 
other  for  those  of  the  staff. 

The  disinfection  house  does  not  admit  of  great  variation.  In  the  smallest 
hospital,  as  in  the  largest,  an  efficient  apparatus  is  a  necessity,  and  the 
difference  in  size  between  the  largest  and  smallest  machine  is  not  very  great. 
The  building  containing  the  disinfecting  apparatus  must  be  so  planned  that 
the  room  in  which  are  the  articles  to  be  disinfected  is  entirely  shut  off  from  all 
communication,  except  by  way  of  the  apparatus  itself,  with  the  room  into 
which  they  are  received  after  undergoing  the  process.  This  arrangement 
involves  the  necessity  of  having  ,two  doors  to  the  machine,  and  the  machine 
itself  must  pass  through  the  dividing  wall  between  the  two  rooms. 

For  the  smaller  class  of  hospital  a  single  coachhouse  to  hold  the  ambu- 
lance will  suffice,  and  indeed  in  many  hospitals  of  large  size  room  for  two 
or  three  ambulances  will  answer  all  the  requirements.  It  may,  however,  be 
desirable  to  arrange  for  a  complete  service,  including  stables  and  rooms  for 
men.  Such  an  ambulance  service  on  a  large  scale  has  been  organised  by  the 
Metropolitan  Asylums  Board. 

Thus  far  reference  has  been  made  to  buildings  only,  and  it  will  be  seen 
that  in  every  detail  the  prevailing  idea  is  that  of  isolation.  In  the  placing  of 
the  buildings  on  the  site  and  in  the  extent'  of  the  site  itself  the  same  idea 
must  be  constantly  kept  in  view.  It  has  been  laid  down  by  the  Medical  De- 
partment of  the  Local  Government  Board  that  no  building  which  is  concerned 
with  the  infected  persons,  such  as  the  wards,  or  with  infected  things,  such  as 
the  mortuary,  laundry,  ambulance  house,  and  disinfection  house,  should  be 
placed  nearer  than  forty  feet  to  the  boundary  of  the  site.  The  reasons  for 
the  adoption  of  forty  feet  as  the  minimum  distance  have  been  arrived  at  by 
a  comparative  study  of  the  history  of  many  hospitals  with  various  conditions 
of  buildings  and  surroundings,  and  experience  has  shown  that  in  well-ordered 
hospitals  with  ample  space  about  the  buildings  there  is  practically  no  risk  of 
the  spread  of  the  infectious  fevers,  other  than  small-pox,  beyond  the  walls  of 
the  hospital. 

It  is,  however,  not  sufficient  merely  to  provide  a  space  of  forty  feet  between 
the  boundary  and  the  infected  buildings,  but  the  space  in  question  must  be 
constituded  a  veritable  sanitary  zone  to  which  no  unauthorised  person  can 
have  access.  An  instance  of  what  actually  occurred  in  a  fever  hospital  will 
perhaps  show  more  clearly  than  anything  else  the  importance  of  this  pre- 
caution. A  woman  whose  daughter  was  a  patient  in  a  fever  hospital  went 
to  inquire  after  her  child,  carrying  in  her  arms  her  baby.  On  entering  the 
hospital  grounds  through  the  gate,  an  ordinary  five-barred  one  with  no  lock, 
she  saw  her  child  at  the  open  window  of  one  of  the  wards.  She  immediately 
made  straight  for  the  window,  kissed  the  child,  and  held  up  the  baby  to  kiss 
its  sister,  and  she  remained  at  the  window  talking  to  her  child  some  twenty 
minutes  before  her  presence  was  discovered.  In  that  twenty  minutes  the 
baby  had  contracted  scarlatina  from  its  sister,  and  from  that  disease  so  caught, 
it  died.     This  hospital,  therefore,  for  lack  of  proper  precautions  and  control, 


750  HYGIENE 

became  an  active  agent  in  the  spread  of  disease,  instead  of  being,  as  it  should 
be,  a  safeguard  and  defence. 

The  entire  site  of  an  isolation  hospital  should  be  surrounded  with  a  wall 
or  fence  at  least  high  enough  to  prevent  ingress  or  egress.  Entrance  to  the 
hospital  grounds  should  be  by  gates,  which  are  kept  under  proper  control, 
and  the  patients  should  not  be  allowed  to  enter  the  forty-feet  space  under  any 
circiunstauces  whatever.  The  importance  of  this  latter  regulation  may  be 
best  illustrated  by  the  fact  that  infection  has  actually  been  conveyed  to 
persons  outside  a  hospital  by  means  of  things  thrown  over  the  boundary 
fence  by  patients. 

As  illustrating  the  practical  application  of  the  foregoing  principles  the 
plans  of  two  isolation  hospitals  are  given,  the  first,  at  Warwick,  being 
an  example  of  the  smaller  type  of  hospital ;  the  second,  at  Newcastle,  being 
an  example  of  a  hospital  suitable  for  a  large  and  populous  town. 

The  hospital  at  Leamington  (fig.  US),  erected  for  the  Warwick  Joint 
Hospital  Board,  consists  at  present  of  four  detached  buildings.  The  adminis- 
tration block  contains  rooms  for  the  matron,  nurses,  and  servants,  and  the 
usual  kitchen  offices.  At  one  corner  of  the  kitchen  is  a  serving  window,  which 
opens  on  to  a  verandah,  whence  the  meals  for  the  patients  would  be  handed 
out.  The  isolation  block  is  planned  on  the  lines  of  the  Local  Government 
model  plan,  and  contains  in  each  half  a  ward  for  three  beds  and  two  wards 
for  one  bed  each,  a  duty  room,  and  a  water-closet  or  slop  sink.  Each  half  is 
provided  with  a  movable  bath  and  the  hot-water  supply  to  each  is  independent. 

The  ward  block  contains  two  wards  for  six  beds  each,  with  water-closet 
and  sink,  a  duty  room,  small  larder,  linen  closet,  and  a  bathroom.  The  latter 
has  a  door  leading  on  to  the  entrance  porch  in  order  that  patients  on  being 
discharged  may  leave  the  bathroom  direct  into  the  open  air,  and  so  not 
return  into  the  corridor  after  putting  on  their  uninfected  clothes. 

The  fourth  block  contains  the  mortuary,  disinfection  house,  ambulance 
house,  and  laundry. 

The  New  City  Hospital  for  Lifectious  Diseases  at  Newcastle-upon-Tyne 
(Plate  Vn.)  occupies  a  site  of  about  eleven  acres.  The  buildings  are  eleven 
in  number,  five  of  them  being  devoted  to  the  reception  of  patients.  At  the 
entrance  is  the  porter's  lodge,  with  carriage  gates  on  either  side,  one  entrance 
leading  to  the  administration  building,  the  other  to  the  various  ward  blocks. 

The  administration  block  is  a  large  building  divided  by  a  corridor  into 
two  parts,  the  front  part  containing  the  residence  of  the  staff,  while  the  back 
wing,  which  is  one  storey  only,  contains  the  kitchen  offices,  stores,  and 
officers'  laundry.  The  small  block  in  the  centre  is  an  isolation  block  having 
accommodation  for  six  patients  in  four  wards  and  two  duty  rooms.  The 
building  is  divided  into  two  halves,  whose  respective  entrances  are  on  opposite 
sides.  The  four  ward  pavilions  are  each  exactly  alike  and  are  arranged  as 
follows  : — 

At  the  entrance  is  a  receiving  room,  which  is  also  used  as  discharging 
room,  and  is  provided  with  means  for  bathing  patients  on  their  arrival  and 
discharge  ;  next  to  this  is  the  duty  room  or  ward  scullery ;  on  the  oppo- 
site side  of  the  passage  is  a  covered  yard,  in  which  are  placed  the  water- 
closet  for  nurses,  coal  store,  and  the  receptacles  for  foul  linen,  dust,  &c. 
Between  the  block  in  which  the  above  rooms  are  placed  and  the  entrance 
to  the  ward  pavilion  proper  a  cross-ventilated  lobby  intervenes.  To  the 
right  and  left  of  the  entrance  lobby  are  wards,  each  containing  ten  beds ; 
immediately  opposite  the  entrance  is  a  nurses'  room  ;  while  projecting  out 
from  the  end  of  each  ward  are  two  small  wards  for  one  bed  each.  The 
nurses'  room  is  provided  with  no  less  than  four  inspection  wuidows,  one 


TLE-UF 
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City    Hospital    for  jN£tc tio uji^^Disea^e^  Newc ASTLt upon Tyn e , 

erected  on  the  Kstale  ol"  [he  CorpuralioiL  at  Walkei-  oti  Tviie. 


h     -d — ^^ — 4^ 


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'OBOy 


752  HYCrlEXE 

into  each  laru^e  ward  and  one  into  each  small  ward.  At  the  further  end 
of  each  ward  are  two  projecting  wings,  one  containing  two  water-closets 
and  a  sink,  the  other  being  a  bathroom. 

The  buildings  shown  in  outline  indicate  the  future  extension  of  the 
hospital.  The  laimdry  and  washhouse,  the  ambulance  house  and  stable, 
the  disinfection  house  and  the  mortuary  are  all  sufficiently  indicated  on  the 
plan,  and  present  no  special  features  calhng  for  remark. 

Besides  the  urban  and  rural  sanitary  authorities,  to  which  reference  has 
been  made  above,  there  is  a  third  class  of  authority  whose  duties  are  con- 
cerned mth  the  isolation  of  cases  of  infectious  disease — port  sanitary 
authorities.  Upon  these  bodies  falls  the  duty  of  isolating  patients  who  are 
found  to  be  suffering  from  any  infectious  fever  on  board  vessels  within  their 
ports.  Vessels  arriving  in  port  are  inspected  by  the  officers  of  the  authority 
if  either  known  or  suspected  of  being  infected. 

The  provision  of  hospital  accommodation  made  by  port  sanitary 
authorities  consists  in  some  cases  of  land  hospitals  and  in  some  cases  of 
floating  hospitals.  As  an  example  of  the  latter  kind,  which  would  appear  to 
be  the  most  suitable  for  the  purpose,  the  following  description  of  the  floating 
hospital  of  the  Tyne  Port  Sanitary  Authority  will  be  interesting  : — 

'  It  [the  hospital]  is  built  on  ten  cylindrical  iron  pontoons,  with  hemi- 
spherical ends.  The  buoyancy  of  each  pontoon  is  53^  tons,  so  that  the 
floating  power  of  the  hospital  is  equal  to  535  tons.  The  pontoons  are  each 
70  feet  long  and  6  feet  in  diameter,  and  resemble  huge  boilers.  Upon  each 
pontoon  there  are  seven  "  saddles,"  which  support  a  strong  framework  of 
iron,  consisting  of  longitudinal  rolled  girders.  These  girders  are  braced 
together  by  diagonal  T-iron,  and  upon  them  is  carried  a  deck  of  creosoted 
timber  which  constitutes  a  platform.  Upon  this  deck  or  platform  the  super- 
structures, or  the  hospital  and  its  adjuncts,  are  erected.  It  is  surrounded 
by  a  neat  handrail,  and  access  from  the  river  is  obtained  by  a  gangway  in 
the  front  centre  of  the  protection  rail.  The  deck  is  partly  occupied  by  three 
main  buildings,  six  smaller  structures,  and  a  mortuary.  The  main  buildings 
are  each  65  feet  long,  23^  feet  wide,  and  about  20  feet  high.  These  are 
divided  into  two  hospital  wards,  one  of  which  will  contain  six  and  the  other 
four  beds.  They  are  spacious,  light,  and  airy  apartments,  having  large 
windows  and  special  means  of  ventilation.  The  interior  is  lined  with 
polished  pitch  pine  in  narrow  strips.  In  each  ward  there  is  a  central  shaft 
through  the  roof,  fitted  with  Kite's  patent  ventilator  for  carrying  off  the 
vitiated  air.  Near  the  floors  there  is  a  series  of  ventilators  for  the  admission 
of  fi-'esh  air,  and  under  the  floor  of  each  apartment  an  air  space  of  about  ten 
inches,  which  will  secure  a  constant  circulation  of  fresh  air.  Beneath  the 
surface  of  the  river  and  the  platform — a  space  of  four  feet — ^there  will  be  a 
perfectly  free  current  of  pure  air.  The  rise  and  fall  of  the  tides  and  the 
current  produced  by  the  spaces  between  the  pontoons  will  prevent  the 
possibility  of  any  impurity  existing  beneath  the  hospital.  Between  the  two 
wards  of  each  hospital  is  an  apartment  for  the  nurse.  These  apartments 
are  fitted  with  glazed  doors  on  either  side,  so  that  the  nurse  can  command  a 
full  view  of  each  ward.  There  are  also  entrances  from  the  deck  to  the  dif- 
ferent wards.  The  main  buildings  are  so  arranged  that  they  can  be  com- 
pletely isolated,  and  they  are  all  fitted  up  alike.  The  platform  is  140  feet 
long  and  80  feet  wide,  and  there  is  ample  space  in  front  of  the  buildings  for 
the  recreation  of  convalescent  patients.  The  space  between  the  pontoons  is 
14^  feet  from  centre  to  centre,  and  each  is  detachable,  so  that  any  one  may 
be  removed  at  will  for  cleaning  and  painting.  They  can  also  be  revolved  in 
their  places  without  removal.     They  are  reached  internally  by  means  of 


THE  DWELLING  '  753 

manholes,  placed  to  correspond  with  trap-doors  in  the  main  or  platform 
deck.'  ' 

The  treatment  of  small-pox  in  an  epidemic  form  has  of  late  years  given 
rise  to  much  discussion  on  account  of  its  apparent  tendency  to  spread  beyond 
the  walls  of  the  hospital  in  a  fashion  entirely  different  from  the  behaviour 
of  other  infectious  fevers  under  similar  conditions. 

This  characteristic  of  small-pox  was  first  particularly  observed  in  1880, 
when  a  special  incidence  was  remarked  as  occurring  in  the  immediate  neigh- 
bourhood of  certain  of  the  hospitals  of  the  Metropolitan  Asylums  Board  in 
London.  An  inquiry  into  the  circumstances  connected  with  the  outbreak 
of  1881  with  reference  to  the  Fulham  Hospital  resulted  in  the  following 
conclusions  by  Mr.  Power,  which  are  characterised  by  Dr.  Buchanan  as 
'  unexpected  but  most  instructive  : ' — 

'  There  has  been  in  each  epidemic  period  an  excessive  incidence  of  small- 
pox on  houses  in  the  neighbourhood  of  the  hospital  as  compared  with  more 
distant  houses  in  Chelsea,  Fulham,  and  Kensington. 

'  The  percentage  of  houses  invaded  in  the  neighbourhood  of  the  hospital 
has  increased.     This  gradation  has  been  very  exact  and  very  constant. 

'  Houses  upon  the  chief  lines  of  human  intercourse  with  the  hospital  have 
not  suffered  more  than  houses  lying  in  other  directions  from  the  hospitals. 

'  In  point  of  time,  there  has  been  a  very  marked  relation  between  the 
varying  use  of  the  hospital  and  the  manifestations  of  excessive  small-pox 
in  the  neighbourhood.  This  relation  has  not  shown  itself  while  the  use  of  the 
hospital  has  been  for  convalescents  only. 

'  The  appearance  of  excessive  small-pox  in  houses  around  the  hospital  has 
never  been  delayed  until  the  hospital  has  become  full  or  nearly  full.  It  has 
been  always  most  remarkable  at  the  time  when  admissions  to  the  hospital 
were  beginning  to  increase  rapidly. 

'  On  comparison  of  different  epidemics,  an  almost  constant  ratio  is  observed 
between  the  amount  of  the  hospital  operations  and  the  degree  of  excess  of 
small-pox  in  the  neighbourhood.'  ^ 

After  careful  and  minute  inquiry  into  the  whole  administration  of  the 
hospital  during  the  period  concerned,  Mr.  Power  was  forced  to  the  conclusion 
'  that  there  must  have  been  some  condition  or  conditions  operating  to  pro- 
duce the  observed  distribution  of  small-pox  around  the  hospital  that  have 
pertained  to  the  hospital  as  such,  and  that  have  been  in  excess  of  the  con- 
ditions for  small-pox  extension  as  usually  recognised.'  ^  Other  and  inde- 
pendent observations  with  regard  to  the  hospitals  at  Hampstead,  Homerton, 
and  Deptford,  and  to  the  old  Small-pox  Hospital  at  Highgate,  produced 
similar  results ;  and  the  whole  question  was  inquired  into  by  a  Eoyal 
Commission. 

The  recommendations  of  the  Eoyal  Commission  with  regard  to  small- 
pox were  that  the  mild  and  convalescent  cases  should  be  provided  for  in 
hospitals  out  of  London,  and  that  the  acute  cases,  too  ill  to  take  a  long  land 
journey,  should  be  treated  in  the  existing  hospitals,  but  that  the  number  of 
the  latter  class  to  be  received  into  anyone  hospital  should  be  limited  to  thirty 
or  forty  cases. 

These  recommendations  the  Metropolitan  Asylums  Board  met  by  pro- 
viding at  Darenth  a  large  small-pox  camp,  and  in  the  river  at  Long  Eeach 
a  floating  hospital  composed  of  three  ships,  the  '  Castaha,'  the  'Atlas,'  and 

1  Annual  Report  of  Medical  Officer  of  Health  to  River  Tyne  Fort  Sanitary  for  the 
Year  ending  December  31,  1886. 

2  On  the  Use  and  Influence  of  Hospitals  for  Infectious  Disease.  Supplement  to  the 
Tenth  Anmial  Report  of  the  Local  Government  Board.     1882. 

VOL.   I.  3  c 


754  HYGIENE 

the  'Endyniion.'  The  camp  is  now  replaced  by  a  permanent  hospital 
for  800  patieiits.  The  '  Castalia  '  and  '  Atlas '  are  appropriated  to  the 
treatment  of  patients,  and  ali'ord  accommodation  for  200  and  150  respec- 
tively, and  the  '  Endymion  '  is  used  for  administration  purposes  and  for 
housing  the  staff.  The  '  Castalia  '  is  a  twin  ship  built  for  service  between 
Dover  and  Calais,  for  which  purpose  she  proved  to  be  unsuitable,  and 
eventually  came  into  the  possession  of  the  Metropolitan  Asylums  Board. 
Upon  the  upper  deck  are  five  huts,  built  obliquely  across  the  long  axis  of  the 
vessel  These  huts  form  the  wards  of  the  '  upper  hospital,'  the  '  lower 
hospital '  being  one  large  ward  the  whole  width  of  the  vessel.  At  each  end 
are  buildings  containing  the  ward  ollices,  reception  rooms,  bathrooms,  lava- 
tories, water-closets,  and  one  isolation  room  on  the  lower  deck  and  two  on  the 
upper  deck.  The  three  centre  wards  on  the  upper  deck  are  54  feet  long  by 
20  feet  wide  ;  the  two  end  ones  are  50  feet  long  by  38  feet  wide. 

A  laundry  and  other  administrative  buildings  have  been  erected  on  the 
shore  abreast  of  the  ships. 

To  convey  patients  to  and  from  the  ships  there  is  a  river  ambulance 
ser%nce,  consisting  of  two  vessels  of  eighty  tons  each  and  fitted  up  with  wards 
for  convepng  patients  in  bed,  and  a  smaller  launch.  In  connection  with 
this  service  there  are  piers  with  receiving  rooms,  waiting  rooms,  &c.,  at 
Blackwall,  Eotherhithe,  and  near  Wandsworth  Bridge.  It  seems  probable, 
therefore,  that  in  any  future  epidemic  of  small-pox  in  London  all  or  nearly 
all  the  patients  will  be  conveyed  down  the  river  to  the  ships,  instead  of  being 
treated  m  the  land  hospitals. 

In  all  hospitals  for  infectious  diseases  provision  must  be  made  to  prevent, 
if  possible,  the  conveyance  of  infection  to  the  outside  world,  either  by  patients 
on  their  discharge  or  by  nurses  or  servants  going  outside  the  gates.  For 
patients  on  their  discharge  a  suite  of  three  rooms  communicating  with  each 
other  should  be  arranged.  The  first  room  should  be  just  sufficiently  large  for 
one  patient  to  undress  in.  In  this  room  the  patient  leaves  his  (or  her) 
infected  clothing.  The  second  or  intermediate  room  is  a  bathroom.  After 
bathing,  the  patient  enters  the  third  room,  where  he  finds  a  complete  suit 
of  clean,  or  preferably  new,  clothing,  which  he  puts  on.  Having  dressed,  he 
should  leave  the  building  by  a  door  leading  directly  into  the  open  air,  and 
should  not  again  enter  any  part  of  the  hospital  buildings.  For  the  staff 
ample  bathing  accommodation  should  be  provided ;  in  order  that,  as  far  as 
possible,  it  should  be  made  a  rule  that  no  one  employed  in  the  hospital  wards 
should  leave  the  grounds  without  having  previously  bathed.  It  is  obvious 
that  such  a  rule  as  this  cannot  be  rigidly  enforced,  but,  nevertheless,  the 
means  of  complying  with  it  should  be  provided,  and  its  observance  should  be 
encouraged  as  far  as  possible. 

Asylums  for  the  Insane. — Although,  as  a  matter  of  fact,  the  great 
majority  of  patients  in  an  asylum  are  persons  in  bodily  health,  the  general 
arrangements  of  the  buildings  are  not  unlike  those  of  a  hospital,  and  the 
general  principles  of  hygiene  are,  to  a  large  extent,  alike  in  both  classes  of 
buildings. 

The  planning  of  an  asylum  is  largely  governed  by  questions  of  classifica- 
tion, disciphne,  and  control.  The  several  classes  of  patients,  usually  at  least 
four  of  each  sex,  have  to  be  separately  accommodated,  workshops  and 
laundries  have  to  be  provided  for  those  who  can  work,  and  all  have  to  be  so 
placed  with  regard  to  each  other  and  the  administration  offices  that  the 
labour  of  supervision  is  economised  as  far  as  is  consistent  with  other  neces- 
sary conditions. 

The  old  system  of  planning  an  asylum  was  to  build  what  practically 


THE  DWELLING  755 

became  one  huge  block,  with  free  communication  of  air  from  one  end  to  the 
other.  It  is  now  generally  conceded  that  such  a  plan  is  hygienically  bad, 
and  that  the  right  system  is  to  divide  the  asylum  into  separate  blocks,  either 
of  the  pavilion  type  or  some  modification  of  the  gallery  ward  plan,  in  such  a 
manner  that  each  section  forms  a  separate  block  in  itself,  and  is  atmospheri- 
cally distinct  from  any  other  block.  The  pavilion  system  obviously  lends 
itself  readily  to  such  conditions,  and  with  each  pavilion  connected  to  the 
next  by  a  covered  way,  with  free  cross  ventilation,  no  interchange  of  air  from 
one  pavilion  to  the  other  can  be  possible.  The  modified  gallery  ward 
plan  has,  however,  advantages  over  the  pavilion  type  in  the  internal 
arrangements  of  day  rooms,  and  provided  there  is  a  sufficiency  of  cross 
ventilation  to  the  dormitories,  it  is  in  some  respects  preferable  to  the  pavilion 
■system. 

Whichever  plan  is  adopted,  it  is  of  the  greatest  importance  to  arrange  the 
day  rooms  in  such  a  way  that  they  are  exposed  to  the  direct  rays  of  the  sun 
to  as  great  an  extent  as  possible.  The  choice  of  a  site,  therefore,  with  a  good 
south  aspect  is  an  important  consideration.  The  site  should  not  be  too  ex- 
posed, but  should  be  protected  from  the  north  and  east.  '  Bleak  exposed 
sites  render  the  buildings  much  more  difficult  to  warm,  and  the  out-door 
recreation  of  the  more  feeble  patients  has  to  be  greatly  curtailed.'  ^ 

The  necessity  for  limiting  the  height  of  the  buildings  to  two  storeys 
involves  the  covering  of  a  large  area  of  ground  ;  a  circumstance  that  cannot 
fail  to  have  a  favourable  influence  upon  the  health  of  the  inmates. 

The  separation  of  the  water-closets  from  the  buildings  to  which  they  are 
attached  by  cross-ventilated  lobbies  is  as  necessary  in  an  asylum  as  it  is  in  a 
hospital,  and  the  details  of  all  such  offices  need  to  be  carefully  thought  out, 
keeping  always  in  view  their  liability  to  injury  from  the  mischievous  habits 
of  the  patients. 

A  liberal  provision  of  baths  must  be  made,  and  in  addition  to  the  ordinary 
baths  it  would  seem  to  be  desirable  or,  according  to  Dr.  Greene, ^  necessary 
to  provide  Turkish  baths  also. 

Every  asylum  must  be  provided  with  its  hospital  for  the  isolation  of  cases 
of  infectious  disease.  The  permanent  accommodation  need  not  be  large, 
prompt  isolation  being  the  object  aimed  at.  Some  modification  of  the 
isolation  block  recommended  for  adoption  by  the  Local  Government  Board 
would  seem  to  meet  the  case  admirably,  in  addition  to  which  a  permanent 
block  of  kitchen  offices  and  laundry,  with  rooms  for  nurses  and  servants,  is 
necessary.  Should  an  epidemic  arise,  the  permanent  accommodation  can 
be  very  readily  supplemented  by  the  erection  of  wooden  huts  or  tents. 

Infirmaries,  Sanatoria,  and  Isolation  Wards  for  Schools. — In  con- 
sidering the  provision  needful  for  the  care  and  treatment  of  diseases  arising 
in  schools,  it  will  be  well  to  divide  the  subject  into  two  classes  :  (1)  the 
boarding  schools  of  the  higher  grade,  including  all  the  large  public  and 
private  schools  ;  (2)  orphanages  and  kindred  institutions  of  the  charitable 
sort  and  the  schools  of  the  pauper  class,  supported  whoUy  or  in  part  by  con- 
tributions from  the  rates. 

In  most  schools  of  the  public  school  type  the  boarders  are  distributed 
about  in  various  masters'  houses,  though  in  some  cases  the  whole  of  them 
are  housed  in  one  building. 

In  every  large  school,  whether  it  consists  of  boarders  only  or  of  both 

'  The  Hygiene  of  Asylums  for  the  Insane.  By  E.  Greene,  F.E.C.P.Ed.,  Medical  Super- 
intendent, County  Asylum,  Northampton. 
^  Op.  cit. 

3  c2 


756  HYGIENE 

boarders  and  day  scholars  (or  '  home  boarders  '),  suitable  provision  must  be 
made  :  (a)  for  cases  of  ordinary  slight  ailments  ;  (b)  for  cases  of  accident  or 
severe  sickness,  not  being  infectious  ;  and  (c)  for  cases  of  an  infectious 
nature. 

For  the  first  class,  which  would  include  boys  sufficiently  out  of  sorts  to 
necessitate  their  staying  away  from  school,  but  not  in  any  case  seriously  ill, 
a  room  or  two  in  each  master's  house,  separated  from  the  general  dormitories, 
is  all  that  is  required. 

The  cases  comprised  in  the  two  other  classes  require  entirely  separate 
treatment,  and  for  them  a  separate  building  or  buildings  must  be  provided. 
The  practice  of  existing  schools  with  regard  to  the  question  of  the  separation 
of  infectious  from  non-infectious  cases  is  by  no  means  uniform  ;  but  the 
opinion  of  the  Medical  Officers  of  Schools'  Association  on  the  question  is  very 
distinct.  They  lay  down  the  principle  that  every  school  ought,  if  possible, 
to  be  provided  with  two  buildings^an  infirmary  for  accidents  and  non- 
infectious cases,  and  a  sanatorium  for  infectious  cases.  No  doubt  this  view 
is  a  sound  one,  and  ought  to  be  adopted  wherever  possible.  On  the  other 
hand,  the  objection  on  the  score  of  the  additional  cost  of  two  establishments 
cannot  be  altogether  disregarded,  especially  in  the  case  of  schools  of  moderate 
size,  and  the  actual  experience  of  existing  schools  must  be  allowed  its  due 
weight. 

The  Eugby  School  Sanatorium  (fig.  145)  is  used  for  all  kinds  of  ill- 
nesses, whether  infectious  or  not,  with  the  single  exception  of  scarlatina,  for 
which  a  separate  cottage  is  provided  in  the  grounds  attached  to  the  sana- 
torium. Here  is  an  instance  of  one  building  serving  for  all  purposes  (with 
the  limitation  noted),  and  of  which  the  medical  officer  says  that  he  has 
never  known  a  single  instance  of  any  disease  spreading  from  one  boy  to 
another.' 

The  question  is  one  of  planning  and  of  administration — planning  in  the 
sense  of  careful  structural  arrangement  for  absolute  isolation  of  the  various 
parts  of  the  building,  and  administration  in  the  sense  of  equally  careful 
precautions  to  prevent  the  structural  isolation  being  rendered  useless  by 
personal  carelessness. 

The  proportion  between  the  number  of  boarders  in  the  school,  and  the 
accommodation  to  be  provided  for  cases  of  sickness,  will  vary  slightly  accord- 
ing to  the  average  age  of  the  pupils.  The  Council  of  the  Medical  Officers  of 
Schools'  Association  consider  that  when  the  average  age  of  pupils  does  not 
exceed  twelve  years  accommodation  for  5  per  cent,  of  the  boarders  is  a  sufficient 
provision  of  beds  for  non-infectious  cases  ;  but  that  when  the  average  age  is 
fifteen  years  the  proportion  of  beds  should  be  raised  to  6  or  7  per  cent.  For 
cases  of  infectious  disease  the  pro%dsion  is  fixed  by  the  same  authority  at  20 
per  cent,  if  measles  is  to  be  included,  and  10  per  cent,  excluding  that  disease. 
The  total  provision,  therefore,  may  be  taken  at  from  25  to  27  per  cent.,  or 
from  15  to  17  per  cent,  excluding  measles.  These  figures  may  be  somewhat 
modified  by  the  following  circumstances  : — 

(a)  If  the  school  is  arranged  on  the  '  house  system  '  and  the  several 
masters'  houses  are  distinct  and  isolated,  the  accommodation  for  infectious 
diseases  may  be  reduced  from  20  to  16  per  cent. 

{b)  If  the  school  mcludes  a  large  proportion  of  day  scholars  a  further 
reduction  of  2  per  cent,  may  be  made. 

So  that  for  infectious  diseases  in  a  school  fulfilling  the  last-named  con- 
ditions a  total  provision  of  14  per  cent,  of  the  total  number  of  boarders  would 
be  regarded  as  sufficient. 

'  Duke's  Health  at  School. 


THE  DWELLING  757 

Taking-  first  the  infectious  class  of  diseases,  the  most  important  point  to 
hear  in  mind  is  that  a  sanatorium  (nsinj?  the  word  as  applying  to  the  huilding 
for  infectious  diseases,  and  as  distinct  from  the  infirmary  or  huilding  for 
non-infectious  cases),  is  primarily  a  building  for  isolation  purposes  ;  a  means, 
that  is,  of  promptly  separating  initial  cases  of  an  infectious  nature  if  possible 
before  the  disease  has  had  time  to  communicate  itself  to  others. 

Inasmuch,  however,  as  it  is  not  always  possible  to  detect  and  to  isolate 
initial  cases  before  the  disease  has  had  time  to  spread,  provision  must  be 
made  for  the  possible  contingency  of  an  epidemic ;  equally  obviously  a  disease 
may  be  contracted  by  several  boys  at  the  same  time  and  from  the  same  cause, 
and  thus  it  may  happen  that  several  cases  of  one  disease  may  arise  simulta- 
neously, which  yet  by  prompt  isolation  may  be  prevented  from  becoming 
epidemic. 

Provision  must  also  be  made  for  the  treatment  of  at  least  two  infectious 
diseases  at  the  same  time.  For,  although  it  rarely  happens  that  two  infectious 
diseases  are  epidemic  in  a  school  at  one  time,  yet  such  an  occasion  might 
arise,  and  it  is  necessary  to  provide  against  it. 

The  accommodation  necessary  to  be  provided  in  a  sanatorium  (assuming 
it  to  be  a  detached  building)  will  comprise  the  following  : — 

1.  Administration,  including  the  matron's  rooms,  kitchen  offices,  linen 
and  other  stores,  servants'  rooms,  and  one  or  two  spare  rooms  for  extra 
nurses  when  required. 

2.  At  least  two  general  wards  for  from  four  to  eight  beds,  eight  being 
the  maximum. 

3.  Two  or  more  isolation  rooms  for  one  bed  each. 

4.  A  convalescent  room. 

5.  Nurses'  rooms,  bathrooms,  and  small  pantries  adjoining  the  wards. 

6.  Water-closets  for  patients,  for  nurses,  and  for  servants. 

7.  Disinfecting  apparatus. 

8.  Ambulance  house. 

9.  Mortuary. 

The  administration  should  be  a  separate  block  placed  centrally  and  com- 
municating with  the  ward  blocks  by  means  of  corridors,  either  entirely  open 
at  the  sides,  or  provided  with  '  through '  ventilation.  The  matron,  who  should 
usually  be  a  permanent  officer,  should  have  a  waiting  room  and  bedroom ; 
and  her  bedroom  should  be  placed  conveniently  near  to  either  one  or  both 
the  isolation  rooms.  As  the  matron  will  also  have  to  act  as  housekeeper,  the 
stores  both  of  linen,  crockery,  and  of  food  will  have  to  be  placed  under  her 
immediate  control.  A  small  cabinet  for  keeping  drugs  &c.  under  lock  and 
key  may  conveniently  be  placed  in  her  sitting  room. 

It  is  very  desirable  there  should  be  a  convalescent  room,  especially  for 
scarlatina  cases,  with  their  long  and  tedious  period  of  convalescence.  It  is 
not,  however,  an  absolute  necessity. 

Attached  to  each  ward  must  be  a  nurses'  room,  large  enough  to  be  used 
us  a  sitting  room  by  day  and  bedroom  by  night.  It  should  be  entered  from  the 
corridor  and  may,  if  desired,  have  a  small  window  overlooking  the  ward, 
though  there  is  little  practical  utility  in  the  latter  arrangement.  For  each 
ward  must  also  be  provided  a  small  pantry  or  duty  room,  sufficiently  large  to 
contain  a  sink,  china  cupboard,  and  a  small  gas  stove  for  warming  beef-tea 
and  preparing  special  invalid  food,  drinks,  &c.  Adjoining  the  last  should 
be  the  bathroom,  so  arranged  that  a  patient  can  on  his  discharge  leave  the 
sanatorium  by  the  casement  window  instead  of  going  back  into  the  corridor. 
The  water-closets  for  the  patients  should  of  course  be  placed  in  projecting 
■wings,  with  a  cross-ventilated  lobby  interposed  between  them  and  the  w^ards. 


758 


HYGIENE 


One  water-closet  must  be  provided  for  "the  nursing  staff  and  one  for  the 
servants,  and  these  also  should  be  cut  otf  by  cross-ventilated  lobbies,  though 
the  latter  might  be  out  of  doors  in  a  small  yard.  Where  possible  a  bathroom 
should  be  provided  for  the  nurses  in  order  that  they  may  have  a  bath  and  a 
complete  change  of  clothes  before  going  outside  the  sanatorium. 

A  properly  arranged  disinfection  apparatus  is  a  necessity  of  the  highest 
importance.  The  building  in  which  it  is  placed  should  be  divided  into  two 
rooms  by  a  brick  wall,  and  the  apparatus  provided  with  two  doors  fitted  so 


A7/VC  EDW/JRD  V/s  SCHOOL 

SHERBORNE . 

/VEW  SffNflTORIUM 
FIRST  FLOOR  PLflN. 

^    .   I   if.   I   M?  -^P  ^°  ^■°  '^' 


Fig.  144. 


that  one  door  of  it  opens  into  one  room  and  the  other  door  into  the  other 
room.  Clothing  to  be  disinfected  will  be  taken  into  one  room,  which  will  be 
devoted  solely  to  the  reception  of  infected  things,  placed  in  the  apparatus, 
and  when  disinfected  taken  out  at  the  door  in  the  other  room,  into  which 
latter,  therefore,  only  disinfected  clothes  will  come.  The  apparatus  should  be 
supplied  -odth  suitable  means  of  drying  the  clothes  if  these  are  exposed  to 
the  application  of  steam. 

An  ambulance  house  will  be  required  where  patients  have  to  be  brought 
from  or  sent  away  to  any  great  distance. 


THE  DWELLING 


759- 


GROUND  FLOOR  PLAN. 

'fni?    ? !£_ 


^ ffpEET. 


A  small  detached  chamber  suitably  constructed  must  be  set  apart  for  the 
temporary  reception  of  the  body  of  any  patient  dying  in  the  sanatorium. 

The  sanatorium  erected  in  1887  for  King  Edward  VI.'s  School  at  Sher- 
borne is  an  example  of  a  building  intended  for  the  treatment  of  infectious 
diseases  only.  It  consists,  as  will  be  seen  from  the  plan  (fig.  144),  of  two  dis- 
tinct blocks  connected  to  each  other  by  covered  ways  entirely  open  at  the 
sides. 

The  centre  block  contains  on  the  ground  floor  the  matron's  sitting  room 
and  bedroom,  servants'  bedroom,  and  kitchen  offices.  Advantage  is  taken 
of  the  fall  of  the  ground  eastwards  to  get  an  additional  floor  under  the 
kitchen,  in  which  are 
placed  the  larder, 
coal  store,  boiler 
room,  and  servants' 
water-closet. 

On  the  upper  floor 
of  this  block  are  two 
isolation  wards  for 
one  bed  each,  having 
a  floor  area  of  117 
feet  and  cubic  space 
of  1,525  feet ;  and  a 
ward  for  four  beds, 
with  a  floor  area  of 
118  feet  and  cubic 
space  of  1,522  feet 
per  bed. 

The  south-east 
block  contains  on 
each  floor  a  small 
pantry,  with  space 
outside  for  a  portable 
bath,  a  nurses'  room, 
and  a  general  ward 
for  eight  beds,  with 
water-closet  and  sink 
room  attached.  Each 
ward  has  a  floor  area 
of  90  feet  and  cubic 
space  of  1,080  feet 
per  bed  ;  in  addition 
to  which  is  a  bay  win- 
dow of  sufficient  size 

to  hold  a  table  at  which  convalescent  boys  can   have  their  meals.     Each 
ward  is  warmed  by  two  hot-water  coils  in  addition  to  a  large  open  fireplace. 

The  central  block  and  the  south-east  wing  only  have  at  present  been 
erected,  the  remaining  wing  being  left  for  future  erection. 

As  an  example  of  an  infirmary  for  both  infectious  and  non-infectious 
eases,  we  are  enabled,  through  the  courtesy  of  the  head  master  (Dr.  Percival) 
and  the  architect  (Mr.  F.  C.  Penrose),  to  reproduce  the  plan  of  the  Eugby 
School  Infirmary,  built  in  the  year  1859.^     (Fig-  145.) 

This  building  consists  of  three  wings,  radiating  from  a  central  circular 

'  The  plan  here  given  is  reproduced,  with  the  autlior's  permission,  from  Dr.  Duke's 
Health  at  School. 


FIRST  FLOOR  PLAN. 

so        So 


o    5   io 


4? 


FEET. 


Fig.  145.— Eugby  School  Infirmary- 


7G0  HYGIENE 

staircase.  On  the  ground  floor  two  of  the  wings  arc  devoted  to  sick-rooms, 
and  the  third  to  the  administration,  matron's  quarters,  kitchen  offices,  and 
bathroom.  The  upper  floor  contains  Ave  sick-rooms  and  the  matron's  bed- 
room. All  diseases,  with  the  exception  of  scarlatina,  for  which  a  separate 
cottage  is  provided,  are  treated  in  this  building,  and  the  medical  officer  con- 
siders that  the  arrangement  of  the  building  lends  itself  admirably  to  the 
purpose. 

The  sick-rooms  give  a  floor  space  of  IIG  feet  and  cubic  space  of  1,820  feet 
per  bed,  allowing  two  beds  to  each  room. 

Hitherto  reference  has  been  made  chiefly  to  schools  of  the  larger  kind, 
but  it  is  equally  essential,  even  in  the  smallest  kind  of  school,  as,  for  instance, 
a  private  boarding  school  of  only  twenty  or  thirty  pupils,  to  provide  adequate 
means  of  isolating  a  case  of  real  or  suspected  infectious  disease.  This  can 
sometimes  be  done  by  setting  apart  a  room  or  two  on  the  top  floor  of 
the  building,  or  in  a  projecting  wing,  and  contriving  a  separate  staircase 
approached  only  from  the  outside,  T^yo  rooms  are,  of  course,  better  than 
one,  and  a  separate  water-closet,  and  if  possible  a  bathroom,  ought  also  to  be 
arranged.  This  arrangement  must,  however,  be  regarded  at  best  as  but  a 
makeshifL. 

Hospital  pro^^sion  is  also  required  for  children  of  the  pauper  class, 
separate  from  the  workhouses,  such  as  those  Avhich  belong  to  metropolitan 
and  certain  large  provincial  Poor-law  imions.  For  schools  of  this  class  pro- 
vision has  to  be  made  :  (ft)  for  the  isolation  or  quarantine  of  children  on 
their  admission  to  the  school,  in  order  to  prevent  the  introduction  of  any 
cases  of  contagious  disease  into  the  general  body  of  the  school ;  these  are 
usually  called  probation  wards  ;  [b)  for  sick-wards  for  cases  of  ordinary  non- 
infectious ailments;  and  (c)  for  isolation  wards  for  cases  of  infectious  disease. 
The  probation  wards  should  be  more  in  the  nature  of  an  'observation  school,' 
so  to  speak,  than  an  infirmary ;  for  the  children  in  them  will  be  to  a  large 
extent  well  and  perfectly  able  to  continue  their  education.  It  has  been  sug- 
gested that,  instead  of  each  school  being  provided  with  its  own  probation 
wards,  a  separate  probation  school  should  be  made  to  serve  for  a  group  of 
several  schools,  '  where  sickly  children,  and  children  admitted  in  a  state  of 
actual  disease,  should  be  kept  for  an  indefinite  time.' ' 

The  infirmary  for  ordinary  sickness  of  a  non-infectious  nature  should  be 
a  separate  building,  removed  from  the  noise  and  bustle  of  class-rooms  and 
playground,  and  amply  provided  with  means  of  classifying  the  various  diseases. 
Such  diseases  as  ringworm  and  other  contagious  disorders  should  be  pro- 
vided for  here,  carefully  separated  from  all  other  diseases. 

The  isolation  hospital  for  infectious  diseases  should  provide  means  of 
treating  simultaneously  at  least  two  different  infectious  diseases.  It  should 
be  constructed  in  the  same  way  as  an  ordinary  fever  hospital,  and  there 
should  be  sufficient  ground  attached  both  for  exercise  for  the  convalescent 
patients  and  for  providing  temporary  increased  accommodation  by  putting 
up  tents  or  huts  to  meet  the  demands  of  an  epidemic. 

The  most  serious  clifficulty,  however,  wdth  which  the  managers  of  these 
large  schools  have  to  cope  is  the  spread  of  ophthalmia.  This  disease,  which 
is  one  to  which  children  of  the  pauper  class  are,  for  various  reasons,  exces- 
sively prone,  is  Hable  to  spread  from  child  to  child  in  the  most  rapid  fashion. 
To  prevent  the  introduction  of  ophthalmia  into  a  school  from  outside  is  one 
of  the  chief  functions  of  the  probation  wards  ;  and  it  was  mainly  with  a  view 

'  Report  on   Ophthalmia  in   the   Metropolitan  Pauper    School.    By  E.  Nettleship, 

r.E.c.s. 


THE  DWELLING  7G1 

to  the  elimination  of  this  disease  that  the  suggestion  referred  to  above  was 
made. 

Ophthahiiia  is,  however,  largely  produced  by  the  conditions  under  which 
these  large  schools  are  carried  on.  And  that  this  is  the  most  important 
part  of  the  subject  is  proved  by  the  fact  that,  according  to  the  authority 
before  cited,  '  the  risk  of  getting  ophthalmia  is  very  far  greater  in  the  metro- 
politan pauper  schools  than  outside  them.'  '  It  may,  and  in  fact  in  one  of  the 
large  metropolitan  schools  it  quite  recently  has  become  necessary  to  provide 
for  the  accommodation  of  a  large  number  of  children  suffering  from  ophthal- 
mia. In  the  case  referred  to,  the  buildings  are  of  a  temporary  nature  ;  but 
it  would  probably  be  better  to  contemplate  such  a  possibility  as  a  large  out- 
break of  the  disease  when  arranging  the  plan  of  a  large  school,  and  to 
provide  at  any  rate  a  permanent  nucleus  to  be  increased  when  necessity 
.arises  by  additions  of  a  more  temporary  nature. 

Ventilation  and  Wakming  op  Hospitals 

Though,  relatively,  good  ventilation  is  of  more  paramount  importance 
in  a  hospital  ward  than  the  mode  of  warming,  the  two  are  so  intimately  con- 
nected, and  in  some  cases  so  independent,  that  it  is  undesirable,  if  not 
impracticable,  to  treat  the  one  to  the  exclusion  of  the  other.  The  object  of 
ventilation  is  to  secure  to  each  patient  a  constant  supply  of  pure  air,  or  air 
of  such  purity  as  is  attainable,  in  such  a  ratio  that  the  air  which  he  inhales 
shall  not  be  polluted  beyond  a  given  standard,  either  by  his  own  or 
other  people's  exhalations.  It  has  been  found  in  practice  that  every 
adult  requires  a  supply  of  3,000  cubic  feet  of  fresh  air  per  hour  in  order 
that  the  total  impurity  of  the  air  may  not  exceed  0*6  per  1,000.  In  a 
^hospital  ward,  therefore,  with  a  cubic  space  of  1,000  feet  per  bed  the  air 
must  be  completely  changed  three  times  in  every  hour ;  at  which  rate,  if 
the  means  of  ventilation  provide  for  steady  and  gradual  movement  of  air, 
the  change  will  be  effected  without  causing  draught.  In  certain  wards,  as 
those  for  fever  and  for  acute  surgical  cases,  at  least  double  this  amount  of 
air  is  necessary.  The  means  adopted  to  provide  this  necessary  movement  of 
air  are  commonly  divided  mto  two  classes — (1)  natural  and  (2)  artificial  or 
mechanical  ventilation. 

In  the  first  class,  or  what  is  commonly  known  as  natural  ventilation,  the 
■  agency  of  windows,  simple  shafts  through  the  walls,  and  the  extracting  power 
■of  open  fireplaces  is  relied  upon  to  produce  the  required  effect.  The  par- 
ticular form  of  windows  best  suited  to  hospital  requirements  and  their  posi- 
tions in  relation  to  each  other  is  discussed  elsewhere.  Air  may  also  be 
admitted  by  so-called  '  Tobin  '  tubes,  which  are  simply  vertical  tubes  con- 
nected at  their  lower  ends  with  the  open  air,  and  with  their  upper  ends  open  • 
ing  into  the  ward,  and  the  object  of  which  is  to  admit  air  in  a  vertical 
direction  ;  air-shafts  through  the  wall  at  the  floor  level,  either  with  or  with- 
out movable  shutters  for  closing ;  or  by  similar  shafts  at  the  ceiling  level. 
Openings  into  the  smoke  flues  or  extraction  shafts  provided  with  flap  valves 
to  prevent  down  draught  are  of  course  only  useful  as  outlets  for  vitiated  air. 
The  openings  at  the  floor  level  should  be  placed  behind  the  beds,  and  are 
intended  to  effect  a  circulation  of  air  at  a  part  of  the  ward  most  liable  to 
stagnation.  The  openings  at  the  ceiling  level  are  accessory  inlets  to  the 
windows,  and  are  frequently  fixed  permanently  open.  If  properly  protected 
with  '  hoppers,'  they  provide  valuable  means  of  ventilation  when  the  windows 
are  shut. 

>  Nettleship,  op.  cit. 


702  HYGIENE 

The  special  form  of  open  fireplace  most  suitable  for  a  ward  need  not  here 
be  discussed  in  detail ;  it  will  be  sufficient  to  point  out  that  a  stove  which  is 
provided  with  a  supply  of  fresh  air  from  without  is  preferable  to  one  which 
depends  entirely  upon  the  ward  for  its  air  for  combustion.  It  is  customary 
in  English  hospitals  to  have  fires  burning  in  tlie  wards  all  the  year  round,  and 
there  is  no  doubt  that  the  practice  is  very  helpful  to  efficient  ventilation. 

Artificial  ventilation  may  be  roughly  divided  into  two  classes  :  (1)  venti- 
lation by  extraction  and  (2)  ventilation  by  propulsion.  Strictly  speaking, 
the  action  of  the  chimney  flue  of  an  open  fire  is  ventilation  by  extraction, 
inasmuch  as  the  extractive  power  of  the  flue  depends  on  the  expansion  of  the 
heated  column  of  air  inside  it.  The  two  systems  exist  side  by  side  at  the 
Lariboisiere  Hospital,  Paris,  where  one-half  of  the  hospital  is  ventilated  by 
a  system  of  propulsion,  and  the  other  by  a  system  of  extraction.  In  the 
former  system  air  is  forced  into  the  wards  by  means  of  a  fan  worked  by  a 
steam  engine,  and  is  warmed  by  passing  over  steam  pipes  before  entering  the 
wards.  The  vitiated  air  is  by  this  system  driven  out  through  the  outlet 
shafts  by  the  force  of  the  entering  stream  of  pure  air.  In  the  system  of 
ventilation  by  extraction  the  motive  power  is  placed  in  a  main  extraction - 
shaft,  into  which  the  various  subordinate  flues  join,  the  power  being  a  hot- 
water  stove,  which  by  heating  the  air  in  the  shaft  causes  it  to  expand,  and  so 
draws  the  air  from  the  wards  through  the  various  shafts.  The  fresh  air  enters 
of  its  own  accord  to  supply  the  place  of  the  air  drawn  off  into  the  outlet 
shafts.     In  this  system  the  warming  is  accomplished  by  means  of  hot  water. 

One  of  the  most  recent  and  probably  most  perfect  systems  of  ventilation 
applied  to  hospital  wards  is  that  adopted  at  the  Johns  Hopkins  Hospital, 
Baltimore.  The  wards  here  are  contained  in  detached  pavilions  of  one  storey 
and  a  basement.  '  The  basement  is  devoted  entirely  to  heating  and  venti- 
lating purposes,  forming  practically  a  large  clean-air  chamber  containing  the 
hot -water  coils  for  heatmg,  and  from  which  the  air  supply  for  these  coils  can 
be  taken  when  desired.  Usually,  however,  the  supply  will  be  taken  directly 
from  the  external  air.  .  .  .  Each  of  the  wards  has  a  separate  aspirating 
chimney,  located  in  an  octagonal  hall  or  vestibule  on  the  connecting  corridor. 
Into  this  chimney  empties  a  foul-air  duct,  which  runs  longitudinally  beneath 
the  centre  of  the  floor  of  the  ward,  and  which  receives  the  air  from  lateral 
ducts  opening  beneath  the  foot  of  each  bed.  The  main  foul-air  trunk  is  of 
wood,  Imed  Avith  galvanised  iron,  and  the  lateral  pipes  are  of  galvanised  iron 
and  cylindrical  in  shape.  A  similar  duct  is  placed  above  the  ceiling  and 
communicates  with  the  ward  by  five  openings  in  the  ceiling  in  the  longitudi- 
nal central  axis.  Just  above  where  this  upper  duct  enters  the  chimney  there 
is  placed  in  the  shaft  a  coil  to  be  heated  by  high-pressure  steam  when  it  is 
necessary  to  quicken  the  aspirating  movement.'  '  It  will  be  seen  from  the 
foregoing  description  that  the  system  adopted  is  one  of  extraction.  The 
position  of  the  extraction  outlets  in  the  wards  can  be  varied  ;  the  air  can  be 
taken  out  either  at  the  floor  level  beneath  the  beds  or  from  the  centre  of  the 
ceihng  ;  and  it  is  intended  to  employ  the  former  method  in  the  winter,  and 
the  latter  in  the  summer.  In  the  basement  is  placed  a  small  propelling  fan 
connected  with  the  heating  coils,  the  function  of  which  is  to  secure  a  thorough 
air  flush  of  the  ward  two  or  three  times  a  day,  and  also  to  supplement  the 
aspirating  shaft  when  occasion  requires.  This  plan  combines,  therefore,  the 
two  methods  of  propulsion  and  aspiration,  though  the  ordinary  method  of 
working  is  by  aspiration  only. 

In  most  hospitals  on  the  Continent  mechanical  means  of  ventilating  the 

•  Ventilation  and  Heating.     By  John  S.  Billings,  M.D.,  Surgeon-General,  U.S.  Army. 


TEE    DWELLING  76a 

wards  are  employed.  The  systena  adopted  at  the  Lariboisiere  has  been 
described  above,  and  may  be  taken  as  a  fair  example  of  French  methods.  In 
Germany  the  use  of  *  calorif^res  '  is  largely  adopted  ;  these  are  large  hot-air 
stoves  usually,  as  at  Dresden,  the  furnaces  of  which  are  situated  in  the  base- 
ment, below  the  wards.  The  upper  part  of  the  '  calorifore '  is  in  the  ward,  and  is 
generally  cased  with  porcelain  tile.  The  fresh  air  is  admitted  in  the  basement 
warmed  by  the  furnace  and  ascends  into  the  wards  through  the  tile-incased 
upper  portion.  In  the  summer  the  fresh  air  is  frequently  made  to  pass  over 
running  water  or  ice  on  its  way  to  the  wards.  In  several  of  the  newer 
hospitals  in  Germany  and  France  the  ventilating  appliances  are  much 
simplified.  At  Halle,  for  instance,  the  windows  and  ventilating  openings  in 
the  roof  are  relied  upon  entirely  ;  while  for  the  winter,  when  the  cold  is  too 
great  to  allow  of  the  use  of  open  windows,  an  arrangement  is  made  by 
which  the  vitiated  air  can  be  extracted  through  an  underground  flue,  com- 
municating with  the  furnace  shaft  of  the  boiler  house.  The  supply  of  fresh 
air  is  warmed  before  it  enters  the  wards  by  passing  over  hot-water  pipes. 

The  question  of  the  relative  value  of  natural  as  compared  with  artificial 
ventilation  is  largely  if  not  entirely  a  question  of  climate.  Both  on  the 
Continent  and  in  America,  it  is  considered  that  the  very  large  variations  of 
temperature  which  occur  demand  the  employment  of  mechanical  aids  to 
ventilation.  In  America  particularly  the  need  for  artificial  ventilation  is 
much  insisted  on,  not  only  for  hospitals  and  other  pubhc  institutions, 
but  also  for  dwelling  houses.  Owing  to  the  very  great  variations  of 
temperature,  and  to  the  extreme  dryness  of  the  air,  especially  in  the 
northern  parts  of  the  United  States,  it  is  necessary  that  a  temperature  of 
from  68°  to  70°  F.  should  be  kept  up  in  dwelling  rooms.  In  this  country,  on 
the  other  hand,  the  variations  of  temperature  are  very  much  less,  and  the 
relative  humidity  of  the  air  permits  of  a  much  lower  temperature  being  kept 
up.  It  may,  indeed,  be  safely  afiirmed  that  there  are  very  few  days  in  the 
average  year  when  the  weather  is  so  cold  as  to  compel  the  closing  of  the 
windows  in  a  hospital  ward.  It  is  therefore  generally  agreed  that  the 
simpler  methods  are  the  most  suitable  for  hospital  purposes  in  this  country. 

There  is,  however,  one  purpose  for  which  some  well-devised  system  of 
mechanical  ventilation  would  seem  to  be  desirable — that  is  for  the  wards  of 
small-pox  hospitals.  But  the  end  to  be  aimed  at  is  not  only  the  ventilation 
of  the  wards,  but  the  complete  destruction  of  all  the  air  that  is  discharged 
from  the  wards.  The  idea  was  first  suggested  by  Dr.  Burdon  Sander- 
son, F.E.S.,  in  his  evidence  before  the  Eoyal  Commission  on  Small-pox  and 
Fever  Hospitals,  of  which  he  was  a  member.  The  plan  proposed  by  Dr. 
Sanderson  consisted  of  an  annular  ward,  with  a  central  circular  shaft  for  the 
extraction  of  foul  air.  The  beds  were  placed  around  the  inner  wall  instead 
of  against  the  outer  wall,  as  is  usual  in  circular  wards,  and  at  the  back  of 
each  bed  was  placed  an  extraction  opening.  The  windows  were  fixtures,  and 
openings  for  the  admission  of  fresh  air,  having  two  square  feet  of  area  each, 
were  placed  in  the  outer  wall.  The  extracting  power  was  to  be  a  fan  pro- 
pelled by  steam,  and  the  air  supply  per  patient  10,000  feet,  moving  at  the  rate 
of  one  mile  per  hour.  The  air  extracted  by  the  fan  was  to  be  passed  through 
a  furnace  of  which  the  heat  should  be  supplied  by  gas.  Upon  this  scheme 
Dr.  Billings  commented  thus.  After  pointing  out  that  the  beds  would  be  more 
conveniently  placed  if  arranged  against  the  outer  wall,  he  says  : — '  A  second 
objection  is  that  the  central  shaft  is  unnecessarily  large,  as  are  also  the  inlets 
into  it.  It  is  not  desirable  to  reduce  the  velocity  of  the  air  at  the  outlets  or 
in  foul-air  ducts  below  four  or  five  feet  per  second,  because  at  very  low 
velocities  a   very  slight  thing  will  disturb  the  currents.     The  velocity  at 


764 


HYGIENE 


the  outlets  has  comparatively  httle  to  do  with  the  production  of  draiights. 
There  seems  to  be  no  necessity  whatever  for  the  use  of  an  aspirating  fan  in 
the  plan  proposed.  If  the  air  is  to  be  heated  to  a  temperature  of  2D0°  F. 
and  upward,  which  is  necessary  to  secure  its  disinfection,  this  heat  will  in 
itself  furnish  all  the  aspirating  power  required.  The  use  of  gas  to  produce 
the  heat  required  for  such  large  quantities  of  air  would  also  be  unnecessarily 
expensive  ;  a  coal  furnace  would  do  the  same  work  at  half  the  cost.' '  Not- 
Avithstanding  these  and  some  other  shortcomings  on  points  of  detail  touched 
upon  by  Dr.  Billings,  the  plan  is  valuable  for  its  suggestiveness.  That  such 
a  mode  of  dealing  with  the  infected  air  of  a  small-pox  ward  is  practicable 
there  can  be  no  doubt ;  the  question  of  the  best  mode  of  carrying  it  out  is 
one  of  detail  and  of  by  no  means  insuperable  difficulty. 


DEAINAGE  OF  THE  DWELLING 

In  this  section  will  be  included  the  drainage  arrangements  and  the  fittings 
in  connection  therewith,  up  to  the  point  where  the  liquid  refuse  from  the 
house  is  discharged  either  into  the  sewer,  cesspool,  or  system  of  irrigation  ; 
in  other  words,  it  will  treat  of  the  conveyance  of  sewage  out  of  the  premises, 
but  not  of  its  ultimate  disposal  either  by  sewers,  cesspools,  or  on  to  the  land. 
It  will  also  concern  itself  exclusively  with  water-borne  systems  of  drainage, 
and  not  with  any  form  of  dry  system. 

The  function  of  a  drain  is  to  convey  to  its  destination  with  as  much 
dispatch  as  possible  all  the  refuse  or  waste  matter  from  a  house  that  can 
properly  be  carried  away  by  the  agency  of  water.  To  accomplish  this  object 
aright,  the  drain  should  be  made  of  such  materials  and  of  such  a  form  as 
to  render  it  impossible  for  its  contents  to  leak  out,  or  for  them  to  accumu- 
late inside.  In  its  form,  therefore,  in  the  nature  of  the  material  of  which  it  is 
made,  and  in  the  mode  of  laying,  a  drain  must  throughout  its  entire  course 
be  such  as  to  offer  the  least  possible  obstacle  to  the  rapid  progress  of  its 

contents   towards  their 

,ll/..4/%.^#'.'!i'ff((((.('/a.f/ff/,.     destination;     it    must 

also  be  impervious  both 
as  to  the  material  of 
which  it  is  made,  and 
as  to  the  joints  between 
its  different  sections. 
Further,  it  is  necessary 
that  the  air  in  the  drain 
should  not  be  allowed 
to  escape  therefrom  ex- 
cept at  such  exits  as 
may  be  provided  for  that 
purpose.  A  drain  must 
therefore  be  both  air- 
and  water-tight. 

Formerly  drains 
were  commonly  made  of 
brick  or  of  slabs  of  stone,  and  were  square  in  section.  Drains  of  this  kind  are 
still  to  be  found  in  many  places  ;  the  example  shown  in  fig.  146  was  sketched 
in  1887  in  a  Surrey  village  and  in  all  probability  exists  to  this  day.  The 
defects  of  such  a  form  of  drain  are  obvious.     In  the  first  place  the  form 

'  Ventilation  and  Beating,  op.  cit.  p.  178. 


Fig.  146. 


TEE  DWELLING  765 

itself  is,  of  all  forms,  the  one  least  adapted  for  facilitating  the  flow  of  water 
along  it.  Secondly,  a  drain  so  constructed  allows  the  contents  to  pass 
readily  through  its  sides  into  the  surrounding  earth.  Brick  drains  with  a 
circular  section  are  an  improvement  upon  the  square  form,  and  may  still  be 
found  occasionally  so  well  made  and  of  such  good  materials  as  to  be  practi- 
cally impervious,  but  they  are  usually  much  larger  than  necessary  or  desir- 
able. Drains  of  this  kind  are,  however,  unsuitable  for  house  drainage,  inas- 
much as  the  surface,  however  well  they  may  be  constructed,  is  comparatively 
rough,  and  the  material  is  liable  to  be  affected  by  time  and  constant  action 
of  running  water.  The  brick  drain  commonly  used  before  the  introduction 
of  glazed  pipes  was,  as  a  rule,  made  of  ordinary  bricks  put  together  with 
mortar.  The  action  of  the  water  and  detritus  carried  with  it  on  the  soft 
bricks  and  the  mortar  joints,  aided  by  the  operations  of  rats,  soon  reduced 
these  drains  to  something  like  the  condition  of  a  sponge ;  and  whenever  a. 
drain  of  this  kind  is  removed,  as  they  frequently  are,  from  old  houses  in 
London  and  elsewhere,  the  surrounding  earth  is  found  to  be  saturated  with 
sewage  that  has  leaked  out  through  the  brickwork  of  the  drain  itself  (fig.  14G). 

The  form  of  drain  now  most  generally  used  is  a  circular  pipe  made  in 
lengths  of  about  two  feet  of  stoneware  glazed  with  a  salt  glaze  and  provided 
at  one  end  of  each  length  with  a  socket  into  which  the  other  or  spigot  end 
of  the  next  pipe  fits.  Between  the  spigot  end  of  one  pipe  and  the  surround- 
ing socket  of  the  next  is  an  annular  space,  which  is  filled  with  some  material 
intended  to  make  the  joint  watertight.  The  material  in  common  use  for  this 
purpose  some  twenty  years  ago,  and  still  extensively  used,  is  puddled  clay^ 
because  where  the  pipes  are  carelessly  laid  on  a  defective  foundation,  sub- 
sidences and  settlements  are  certain  to  occur,  and  the  clay  would  give  with 
the  altered  position  of  the  pipes  ;  whereas  if  a  harder  material,  such  as  cement, 
were  used  for  jointing  these  defectively  laid  pipes,  breakages  would  be  likely 
to  occur  in  the  pipes,  sockets,  or  joint.  The  clay,  however,  in  the  course  of 
a  comparatively  short  time,  will  inevitably  be  washed  out  of  the  joints,  and 
for  all  the  protection  it  affords  might  just  as  well  have  been  omitted  and  the 
pipes  laid  with  open  joints.  Portland  cement,  if  carefully  applied,  makes  an 
excellent  and  lasting  joint ;  but  care  needs  to  be  taken  to  ensure  that  any 
cement  that  squeezes  out  of  the  joint  into  the  interior  of  the  pipe  is  entirely 
wiped  off,  or  it  will  '  set '  and  leave  ridges  inside  that  will  form  so  many 
obstructions  to  the  flow  of  water,  and  lodging  places  for  solid  matters  carried 
down  with  the  sewage.  It  is  needful  also  to  be  certain  that  the  cement  is 
properly  applied  all  round  the  joint,  as  careless  or  dishonest  workmen  will 
often  make  a  neat  joint  so  far  as  it  is  visible  on  the  top  of  the  pipes,  while 
leaving  the  underside  entirely  devoid  of  cement.  Another  kind  of  joint,  which 
has  been  much  used  of  late  years,  is  made  by  casting  on  to  the  spigot  and 
socket  of  each  pipe  a  ring  of  specially  prepared  patent  material,  the  two  rings 
being  fixed  in  situ  with  a  composition  of  Russian  tallow  and  resin.  This 
joint  will  bear  testing  with  water  within  a  very  much  shorter  time  after  its 
completion  than  is  the  case  with  cement ;  and  there  is,  moreover,  nothing  to 
squeeze  up  inside  the  pipe  after  the  joint  is  made.  It  is,  however,  desirable 
to  make  sure  of  its  durability  by  adding  a  ring  of  cement  outside  the  patent 
joint. 

Of  not  less  importance  than  a  watertight  joint  is  a  firm  and  sohd  founda- 
tion on  which  to  rest  the  pipe.  If  a  drain  be  laid  in  a  soft  and  yielding  bed, 
subsidence  will  inevitably  take  place,  with  the  result  that  the  joints,  if  of 
cement,  will  be  broken,  and  the  drain  will  cease  to  be  watertight,  while  the 
gradient  will  be  rendered  irregular  and  deposits  of  sewage  will  occur  in  the 
drains. 


706 


HYGIENE 


Fig.  147. 


If,  therefore,  tlie  soil  upon  ^Yllicll  a  drain  has  to  be  laid  is  not  of  sufficient 
solidity  and  compactness  as  to  render  all  chance  of  subsidence  impossible, 
the  pipes  must  be  laid  on  a  bed  of  concrete  of  such  thickness  as  the  nature  of 
the  case  demands,  but  never  less  than  three  inches 
under  the  centre  of  the  pipes.  When  the  pipes  have 
been  laid  and  tested  the  concrete  should  be  filled  in 
around  them  up  to  the  line  of  the  horizontal  dia- 
meter (see  fig.  147). 

The  fall  or  inclination  to  be  given  to  a  drain  is  a 
point  upon  which  no  definite  rules  can  be  laid  dowTi, 
as  the  possible  fall  will  always  depend  upon  the  cir- 
cumstances peculiar  to  each  case.  It  must,  however,  be  premised  that  the 
fall  should  be  a  regular  one,  and  not,  as  is  too  often  found  to  be  the  case 
in  carelessly  executed  work,  that  one  pipe  should  have  a  fall  of  some  two  or 
'-hree  inches,  the  next  be  laid  quite  flat,  and  the  next  falling  perchance  the 
reverse  way.  Having  found  the  level  of  the  starting  point  of  the  dram,  and 
the  level  of  the  outfall,  the  pipes  should  be  laid  with  an  even  fall  from  point 
to  point.  What  the  fall  is  to  be  must,  as  has  been  said,  depend  upon  circum- 
stances ;  but  it  may  be  taken  as  a  general  rule  that  a  house  drain  should 
have  a  fall  of  at  least  1  in  50.  When  the  fall  obtainable  is  less  than 
this,  the  scouring  or  cleansing  of  the  drains  cannot  be  effectually  accom- 
plished without  the  aid  of  special  flushing,  of  which  further  mention  will  be 
made  hereafter. 

The  following  table  ^  of  the  discharge  per  minute  of  various  sizes  of  drains 
when  running  full  will  be  found  useful : — 


Velocity  3  feet  per 
second 

Velocity  4i  feet  per 
second 

Velocity  6  feet  per 
second 

Velocity  9  feet  per 
second 

Diameter 
of  pipe 

1 

FaU 

Discharge 

per 

minute 

Fall 

Discharge 

per 

minute 

Fall 

Discharge 

per 

minute 

Fall 

Discharge 

per 

minute 

Inches 

Gallons 

Gallons 

Gallons 

Gallons 

3 

lin   69 

54 

lin   30-4 

81-0 

1  in  17-2 

108 

1  in    7-6 

162 

4 

lin    92 

96 

lin   40-8 

144-0 

1  in  23-0 

192 

1  in  10-2 

288 

6 

1  in  138 

216 

lin   61-2 

32  -0 

1  in  34-5 

432 

1  in  15-3 

648 

9 

1  in  207 

495 

lin    92-0 

742-5 

lin  51-7 

990 

1  in  23-0 

1,485 

12 

lin  276 

876 

1  in  122-4 

1314-0 

1  in  69-0 

1752 

1  in  30-6 

2,628 

The  size  of  pipes  to  be  employed  is  also  a  matter  which  must  depend  on 
circumstances.  As  a  rule,  house  drains  are  frequently  laid  with  pipes  of 
much  too  large  diameter  ;  and  unfortunately  many  local  authorities  are  apt 
to  insist  upon  the  use  of  the  larger  pipes,  on  the  plea  that  the  smaller  ones 
are  more  readily  choked.  If  drains  are  always  to  be  laid  in  the  old  careless 
and  haphazard  way,  there  is  some  justification  in  the  argument ;  but  as  the 
object  of  good  drainage  is  to  render  the  occurrence  of  a  stoppage  impossible, 
there  is  no  need  to  unduly  increase  the  area  of  pipe  surface  which  has  to  be 
flushed  and  the  capacity  which  has  to  be  ventilated.  Drain  pipes  are  made 
usually  in  three  sizes— of  4  in.,  6  in.,  and  9  in.  diameter.  The  area  of  a  4-in. 
pipe  is  12-56  inches,  while  that  of  a  6-in.  pipe  is  28-27  inches,  or  considerably 
more  than  double  that  of  a  4-in.  pipe  ;  while  a  9-in.pipe  has  a  sectional  area 
of  63-61  inches.     The  same  amount  of  water,  therefore,  that  would  fill  a  4-in. 


^  From   A    Handbook  of  House   Sanitation. 
London,  1882. 


By  E.  F.   Bailey-Denton,  C.E.,   B.A. 


THE  DWELLING 


767 


pipe  would  not  nearly  half  fill  a  6-in.  pipe  ;  consequently  the  flushing  power 
of  the  same  volume  of  water  is  proportionately  reduced.  As  a  general  rule,  a 
4-in.  pipe  is  sufficient  for  the  drainage  of  moderate- sized  houses,  a  6-in. 
will  suffice  for  a  large  mansion,  while  D-in.  pipes  are  only  needed  for  the  main 
and  outfall  drains  of  large  institutions. 

No  drains  ought  to  be  laid  under  houses  when  ili  is  possible  to  lay 
them  outside.  In  some  instances,  however,  as  in  houses  m  terraces  or 
streets  of  towns,  the  drains  must  pass  under  the  house  in  order  to  reach  the 
sewer.  In  such  cases  extra  precautions  are  necessary  to  prevent  the  leakage 
of  air  or  water  into  the  soil  under  the  house.  A  good  plan  is  to  use  iron 
instead  of  stoneware  pipes,  one  advantage  of  which  is  that  there  are  fewer 
joints  to  make,  the  pipes  being  cast  in  10  or  12  feet  lengths  instead  of 
2  feet ;  and  the  joints  can  be  securely  caulked  with  lead.  In  any  case  the 
pipes,  whether  they  be  of  stoneware  or  of  iron,  should  be  completely  encased 
in  concrete. 

The  paramount  necessity  for  the  greatest  accuracy  in  laying  out  a  system 
of  drainage  can  hardly  be  too  strongly  insisted  upon.  Absolute  precision 
not  only  in  designing  the  scheme,  but  in  carrying  it  out  to  its  smallest  details, 


Pig.  148. 

is  as  important  in  the  drainage  of  a  house  as  it  is  in  the  sewerage  of  a  town. 
Unfortunately,  however,  while  the  highest  engineering  skill  is  brought  to 
bear  on  the  wholesale  disposal  of  the  sewage  of  a  large  community,  the 
details  of  drainage  to  individual  houses  are  too  often  entrusted  to  the 
unskilled  hand  of  a  builder's  foreman. 

The  plan  upon  which  the  drains  of  a  house  are  laid  is  also  a  matter  which 
requires  careful  consideration.  Provision  should  be  made  for  ready  inspec- 
tion of  every  part  of  the  drains,  without  its  being  necessary  to  dig  out  the 
ground  or  tear  up  floors.  This  can  only  be  done  effectually  if  the  drains  are 
laid  out  in  straight  lines  from  point  to  point,  and  if,  at  each  change  of  direc- 
tion or  junction  between  two  or  more  pipes,  an  access  chamber  or  manhole 
is  built.  The  old-fashioned  plan  of  laying  drains  in  all  sorts  of  directions, 
using  curved  lines  by  preference  where  straight  lines  would  have  better 
accomplished  the  purpose,  is  now  very  generally  abandoned.  Examiales  of 
good  and  bad  plans  of  drainage  are  given  at  figs.  148  and  149.     An  access 


768 


HYGIENE 


chamber  or  manhole  is  formed  by  building  a  square  pit  of  sufficient  size  to 
permit  of  a  man  getting  down  into  it  to  examine  the  drain.  At  the  bottom 
of  the  pit  the  main  drain  runs  through  in  a  glazed  channel  or  half-pipe,  and 
the  branch  pipes  all  deliver  either  on  to  the  main  channel  or  at  the  same 
level,  and  are  formed  of  similar  half-pipes  curved  on  plan  (figs.  150  and  151). 


Fig.  149. 


The  top  of  the  manhole  is  covered  with  a  hinged  iron  lid,  which  should  have 
an  air-tight  joint  (fig.  151). 

With  such  a  system  of  drainage,  having  practically  free  access  to  every 
part,  the  application  of  any  test  desired  is  rendered  very  simple. 

All  drains  should  be  tested  when  complete  in  order  to  ascertain  if  they 


Fig.  150. 


fulfil  the  required  conditions  of  soundness.  This  is  most  effectually  done  by 
plugging  the  lower  end,  and  filling  the  pipes  with  water,  which  should  be 
allowed  to  stand  for  such  a  time  as  experience  will  suggest  before  the  drain 
is  passed  as  complete  and  perfect.     The  water  test  is  a  very  severe  one, 


THE  DWELLING 


769 


especially  in  long  lengths  of  drains  and  where  the  fall  is  great,  and  will 
infallibly  detect  any  faulty  places  either  in  pipes  or  in  joints.  Pipes  can 
now  be  had  which  have  been  submitted  to  hydraulic  pressure  and  which  are 
marked  '  tested  ; '  a  great  advantage  to  the  builder,  as  the  makers  undertake 
to  replace  any  pipes  which  prove  defective  under  test  when  laid  and  jointed. 

Traps  are  appliances  used  for  the  purpose  of  keeping  back  the  sewer  air 
from  the  drains  or  the  drain-air  from  the  house  or  its  surrounding  air ;  and 
the  method  by  which  the  air  is  kept  back  is  by  the  interposition  of  a  body 
of  water,  called  a  '  water  seal,'  between  the  inlet  to,  and  the  outlet  from,  the 
trap. 

A  form  of  trap  which  was  almost  universally  used  in  former  times,  and  is 
a,t  times  met  with  now,  is  what  is  known  as  a  '  mason's  '  or  '  dip  '  trap.  It 
consists  (fig.  152)  of  a  square  chamber  divided  across  the  middle  by  a  vertical 
slab  of  stone  which  extends  up  to  the  top  but  stops  short  of  the  bottom 
sufficiently  to  allow  the  sewage  to  pass  from  the  first  into  the  second  division. 
These  dip  traps  are  often  found  with  a  very  considerable  space  between  the 
bottom  of  the  dip-stone  and  the  floor  of  the  chamber  ;  the  result  of  which 


Fig.  151. 

arrangement  is  a  very  considerable  accumulation  of  solid  refuse  on  the  floor. 
At  best  this  form  of  trap  is  a  most  defective  one,  and  becomes  a  small  cess- 
pool, or  storage  tank,  for  decomposing  organic  matter. 

The  only  suitable  kind  of  trap  to  be  used  for  cutting  off  the  house 
drain  from  the  sewer  or  cesspool  is  what  is  known  as  a  '  siphon '  trap.  It 
is  in  reality  not  a  siphon  at  all,  but  a  pipe  bent  in  such  a  way  that  there  is 
always  a  water  seal  between  the  inlet  and  the  outlet.  There  are  several 
forms  of  trap  suitable  for  the  purpose  ;  the  one  shown  in  fig.  153  was  devised 
by  Mr.  Eogers  Pield,  C.E.,  specially  for  fixing  in  connection  with  manholes, 
and  has  at  its  inlet  a  short  piece  of  open  channel  or  half-pipe.  The  points 
to  be  observed  about  a  trap  for  this  purpose  are  that  its  parts  shall  be  so 
formed  as  to  facilitate  the  thorough  scouring  out  of  it  when  there  is  a  flow 
of  water  through  the  trap  ;  a  slight  dip  at  the  inlet,  which  should  be  well 
rounded,  also  tends  to  add  force  to  the  water  at  its  entrance. 

A  modification  of  this  trap  (fig.  154)  has  been  devised  by  Professor  Cor- 
field  with  a  view  of  giving  greater  effect  to  the  scour  of  water  through  it  by 
making  the  channel  at  the  entrance  to  the  trap  somewhat  of  an  egg-shape ; 
but  in  this  modified  trap  an  arrangement  has  been  contrived  so  as  to  form  a 
bye-wash  through  the  arm  of  the  trap  provided  for  affording  access  to  the 
VOL.  I.  3d 


770 


HYGIENE 


Fig.  152. 


drain  below  the  trap.  This  bye-wash  is  furnished  with  a  plug-valve  having 
a  chain  or  rod  attached  to  it  and  brought  up  to  the  top  of  the  manhole  so 
that,  in  the  event  of  a  stoppage  occurring  in  the  trap  and  the  manhole  be- 
coming in  consequence  filled  with  sewage  before  the  stoppage  is  discovered, 

the  bye-wash  can  readily 
bo  opened  to  allow  the 
sewage  to  pass  away  until 
the  level  of  the  bye-wash 
is  reached,  when  access  to 
the  trap  can  more  readily 
be  obtained  for  removal  of 
the  obstruction,  and  thus 
the  necessity  for  pumping 
or  baling  out  the  manhole 
is  removed. 

To  receive  the  surface 
water  from  yards  and  other 
paved  places,  gulley  traps 
are    used.       These    traps 
should  be  as  simple  in  con- 
struction as  possible,  and 
should  certainly  not  be  of 
the  form  known  as  '  bell 
traps.'     In  this  trap  (fig. 
155)  there  is  a  fixed  part 
which  contains  in  the  cen- 
tre the  open  mouth  of  the 
pipe   around  about  which 
is  an    annular    space     to 
hold  water,  and  a  movable 
part  which   consists  of    a 
grating   and    an    inverted 
cup  or 'bell.'     The   edges 
of  the   cup   dip   into    the 
water    contained     in    the 
annular  space,  and  so  form 
a  water  seal.     The  defects 
of  this  trap  are  that   the 
water  seal  is  very  shallow, 
often  not  exceeding  a  quar- 
ter of  an  inch  in  depth,  so 
that  a  very  small  amount 
of  evaporation  suffices   to 
unseal   the   trap,  and  the 
movable  part  is  apt  to  get 
removed  or    broken  Avhen 
the  protection  of  the  water 
seal,   such  as  it  is,    van- 
ishes. 

For  ordinary  purposes,  and  where  the  water  washed  into  the  trap  is  not 
liable  to  be  charged  with  sand  or  other  solid  matters  to  any  great  extent, 
a  suitable  form  of  trap  is  that  shown  in  fig.  156  ;  but  where  such  sohd 
matters  are  likely  to  be  present  m  considerable  quantities,  a  trap  made  as 
in  fi».  157  with  a  receptacle  for  mtercepting  the  silt  &c.  is  more  useful. 


Fig.  153. 


3Aj^3^— -^^^g 


THE  DWELLING 


111 


Fie.  155. 


Fig.  156. 


The  bucket  is  made  of  iron  and  has  a  handle  for  lifting  it  out,  and  the  sur- 
face both  inside  and  out  should  be  tarred  and  sanded  to  protect  it  from  rust. 
To  prevent  the  passage  of  drain-air  into  a  house  by  way  of  the  waste- 
pipes  of  such  iittings  as 
sinks,  baths,  and  lava- 
tories, it  is  necessary  to 
cause  such  waste-pipes 
to   be   absolutely  sepa- 
rated  from   the    drains 
and    to   deliver   in   the 
open   air   over   trapped 
guUeys.     In  the  model 
bye-laws      issued       by 
the  Local  Government 
Board  for  the  guidance 
of  local  sanitary  autho- 
rities it  is  provided  that 
an  open  channel  shall 
intervene   between    the 
end   of  the    waste-pipe 
and  the  trap,  and  that 
the  interval  between  the 
pipe  and  the  trap  shall 
be  at  least   18    inches. 
The  object  of  this  fur- 
ther    provision     is     to 
make  the  break  in  the 
continuity  of  the  waste- 
pipe     and     the     drain 
greater,  and  so  to  lessen 
the   possibility    of   foul 
air    passing    from    the 
gulley  into   the  waste- 
pipe,  and  also  to  render 
the  end  of   the  waste- 
pipe  more  accessible  for 
cleansing  purposes.  For 
it  must   always  be  re- 
membered that   a  pipe 
through   which    greasy 
water      is      constantly 
passing,  as  is  the  case 
both  with  scullery- sink 
wastes     and.    lavatory 
wastes,  is  Hable  to  be- 
come   very    foul    with 
grease  and  soap  and  to 
require  periodical  clean- 
ing.    For   this    reason 
it  will  be  seen,  when  the 
inside  fittings  come   to 
be  discussed,  it  is  always  desirable 
itself. 

The  trap  into   which  waste-pipes 


Pig.  157. 


to  have   a   trap   upon  the  waste-pipe 


from  smks  discharge 


should   be 
3d  2 


as 


772 


HYGIENE 


Fig.  158. 


shallow  as  it  can  be  made  consistently  with  the  provision  of  a  sufficiently 
deep  water  seal,  so  that  the  body  of  water  contained  in  it  may  be  reduced 
as  much  as  possible  in  bulk.     A  suitable  form  of  trap  is  shown  at  fig.  158. 

While  the  necessity  for  traps  in  proper  places  must  not  by  any  means 
be  overlooked,  it  is  equally  necessary  to  guard  against  the  undue  multi- 
plication of  traps  or  the  fixing  of  them  in  places  where  they  are  not  required. 
For  the  existence  of  a  trap  necessarily  means  a  certain  check  upon  the  velocity 
of  the  flow  of  water  in  the  drains,  and  every  trap  which  is  not  absolutely 
needful  is  an  obstruction  to  the  passage  of  sewage.  Traps  at  the  feet  of 
soil-pipes,  for  instance,  are  not  only  unnecessary,  but  positively  harmful,  for 
they  prevent  the  free  flow  of  air  up  from  the  drain  through  the  whole 
length  of  the  soil-pipe  which  is  so  necessary  a  part  of  the  ventilation  of 
drains. 

The  practice  of  closing  or  sealing  up  traps  which  receive  the  ends  of  rain- 
water and  waste-pipes  is  one  which  is  at  variance  with  good  sanitation. 

When  a  trap  is  closed  up,  as  in  fig. 
159,  it  is  not  only  difficult  to  get  at 
it  when  required  for  cleansing  pur- 
poses, but  any  foul  or  decomposing 
matter  retained  either  in  the  trap- 
ping water  or  against  its  sides  will 
pollute  the  air  in  the  waste-pipe 
and,  of  course,  also  that  of  the 
building. 

The  regular  and  effectual  scour- 
ing of  drains  depends,  as  a  rule, 
upon  the  water  which  is  discharged 
into  them  from  water-closets,  baths, 
and  sinks — the  water,  in  fact,  which 
is  used  for  the  various  domestic 
purposes  in  the  daily  life  of  the 
household.  It  is  desirable,  where 
it  can  be  arranged,  to  supplement 
this  by  tanks  provided  for  the  ex- 
press purpose  of  flushing  out  the 
drains  with  a  larger  body  of  water 
than  ordinarily  passes  away  from 
the  houses  through  the  various 
fittings ;  and  where  the  drains 
have  but  slight  fall  some  provision  of  the  kind  becomes  a  positive  necessity. 
It  is  further  desirable  that  the  action  of  these  tanks  should  be  automatic, 
and  for  this  purpose  the  annular  siphon  devised  by  Mr.  Kogers  Field, 
M.I.C.E.,  is  most  valuable.  This  apparatus  (fig.  160)  consists  of  a  siphon 
the  longer  arm  of  which  is  placed  within  the  shorter  arm  ;  the  siphon  is 
fixed  in  a  tank  in  such  a  way  that  the  longer  arm  passes  through  an  open- 
in»  in  the  floor  and  dips  into  a  small  body  of  water  kept  in  place  by  a  weir, 
and  the  shorter  arm  is  kept  clear  of  the  floor  to  allow  of  the  passage  of  water 
between  the  two.  When  the  tank  is  filling,  the  water  rises  simultaneously 
within  it  and  up  the  annular  space  in  the  siphon.  When  it  reaches  the  top 
of  the  lower  arm  it  is  directed  by  a  projecting  lip  towards  the  centre,  and 
in  its  descent  carries  with  it  sufficient  air  to  form  a  partial  vacuum  and 
thus  start  the  siphon.  These  tanks  are  sometimes  used  also  to  collect  waste 
water  from  sinks,  baths,  and  lavatories,  and  so  to  concentrate,  as  it  were,  the 
flushing  power  of  the  water   which   would   otherwise   pass  away  in  small 


Fig.  159. 


THE  DWELLING 


m 


discharges.     The  siphons  can  be  made  in  many  different  sizes  and  appHed 
to  tanks  of  from  twenty  gallons  capacity  upwards. 

The  pipes  hitherto  discussed  have  for  the  most  part  been  those  which 
are  fixed  below  the  ground  ;  there  are,  in  addition,  some  pipes,  such  as  rain- 
water pipes  and  soil-pipes,  which  are  fixed  vertically  against  the  outside  walls, 
and  for  which  the  materials  ordinarily  used  for  underground  drains  are 
unsuitable.  Eain-water  pipes  are  usually  made  of  iron,  lead  being  used  only 
in  the  most  expensive  works,  and  where  elaborate  and  ornamental  work  is 
required.     Cast  iron  is  for  all  practical  purposes  a  sufficient  and  suitable 


INSPECrWH  SHAFT. 


ROAD. 


Fig.  160. 

material  for  rain-water  pipes.  The  pipes  should  be  round,  and  should  be 
fixed  so  that  there  is  a  free  space  of  at  least  one  inch  between  the  pipe  and 
the  wall.  The  object  of  this  is,  first,  that  if  a  stoppage  or  a  crack  occurs  in 
the  pipe,  as  possibly  may  happen  after  frost,  the  water  which  leaks  out  of 
the  pipe  will  not  run  down  the  wall  and  so  cause  dampness  therein  ;  and 
secondly,  in  order  that  the  pipe  can  be  painted  all  round. 

For  soil-pipes  unquestionably  the  best  material  is  lead.    The  pipe  should 
be  of  the  kind  known  as  '  drawn,'  in  long  lengths,  made  without  seam 
and  the  lead  of  which  it  is  made  should  weigh  8  lb.  to  the  superficial  foot. 


774  HYGIENE 

which  is  equal  to  about  "136  in.  in  thickness.  All  the  joints  should  be  soldered 
and  the  pipe  should  be  supported  by  properly  made  '  tacks  '  (or  flaps  of  lead 
fastened  to  the  back  of  the  pipe)  to  the  walls.  Every  soil-pipe  should  be 
connected  directly  to  the  drain,  and  should  be  carried  up  its  full  diameter  as 
a  ventilating  pipe  to  a  suflScient  distance  above  the  heads  of  all  neighbour- 
ing windows.  Opinions  difl'er  as  to  the  best  means  of  finisliing  the  open 
end  of  a  ventilating  pipe,  some  authorities  being  in  favour  of  cowls,  while 
others  consider  that  a  simple  open  mouth  is  equally  efficacious.  The 
extracting  power  of  the  best  cowls  is  certainly  doubtful  ;  and  an  efficient 
protecting  cap  may  be  made  by  widening  out  the  mouth  of  the  pipe  to  about 
twice  its  area,  and  fixing  on  it  a  spherical  wire  grating  to  keep  the  aperture 
free  and  open. 

Waste-pipes  from  fittings  on  upper  floors  must  also  be  connected  to 
vertical  pipes  fixed  outside  the  walls.  These  pipes  should  also  be  made  of 
lead,  and  where  hot  water  is  hkely  to  be  discharged,  the  joints  should  be 
made  to  allow  of  expansion  and  contraction.  These  pipes  should  be  venti- 
lated, and  the  ventilating  pipes  carried  up  above  the  windows. 

Ventilating  pipes,  whether  for  soil-  or  waste-pipes,  need  not  be  made  of 
the  same  weight  of  material  as  the  pipes  they  ventilate. 

Cast-iron  pipes,  unless  made  of  very  heavy  metal  and  provided  with 
sockets  strong  enough  to  bear  caulking  with  lead,  should  never  be  used  for 
soil-pipes.  The  ordinary  rain-water  pipes  so  commonly  used  with  the  joints 
made  of  red  lead  are  never  air-tight  as  a  soil-pipe  should  be. 

The  practice  of  discharging  waste-pipes  into  rain-water  heads  is  not  to  be 
commended.  The  inside  of  the  head  affords  a  lodgment  for  grease  and 
becomes  often  very  foul,  and  a  source  of  nuisance  very  perceptible  at  the 
neighbouring  windows. 

Where  it  can  possibly  be  avoided,  soil-pipes  ought  never  to  be  fixed  inside 
a  building.  The  common  practice  of  fixing  the  soil-pipe  in  a  chase  in  the 
wall,  and  then  casing  it  over  with  a  wooden  casing,  is  a  very  bad  one,  and  has 
been  the  cause  of  much  evil.  It  has  frequently  happened  that  on  investi- 
gating the  cause  of  some  serious  leakage  of  drain  air  inside  a  house  the  evil 
has  been  traced  to  a  hole  made  by  a  carpenter  in  driving  a  nail  right  through 
the  pipe  when  fixing  some  piece  of  woodwork.  Neither  is  it  permissible  to 
make  one  pipe  do  the  double  duty  of  soil-  and  rain-water  pipe.  In  the  first 
place,  if  this  is  done  the  rain-water  pipe  cannot  properly  be  disconnected  at 
its  foot  as  it  ought  to  be  ;  and  secondly,  when  the  rain-water  pipe  is  running 
full  or  nearly  full  of  water  during  a  storm,  its  function  of  ventilating  the  soil- 
pipe  is  necessarily  in  abeyance,  and  that  at  a  time  when  it  is  most  needed. 

Water-closet  apparatus  may  be  divided  into  four  classes  : — (1)  Those  of 
the  '  hopper '  or  '  wash-out '  kind,  which  are  simply  basins  with  traps  of 
earthenware,  and  which  are  flushed  either  by  a  waste-preventing  cistern  or 
by  a  valve  fixed  in  the  supply  cistern;  (2)  pan  closets;  (3)  valve  closets ; 
and  (4)  trough  closets.  The  first  three  of  these  classes  have  been  fully, 
described  in  the  earlier  pages  of  this  article,  and  it  is  here  only  necessary  to 
describe  the  trough  closet,  which  is  an  apparatus  specially  suited  for  outdoor 
purposes  to  public  institutions  (workhouses,  schools,  prisons,  barracks,  &c.), 
and  to  latrines  in  public  places.  It  consists  of  a  trough,  made  either  in  iron 
or  in  glazed  earthenware,  with  a  weir  at  the  outlet  end  for  the  retention  of 
a  sufficient  body  of  water  in  the  trough,  and  a  flushing  cistern  at  the  upper 
end.  The  trough  should  be  round  in  section  and  should  be  slightly  inclined 
towards  the  outlet,  and  the  capacity  of  the  flushing  tank  should  be  propor- 
tionate to  the  length  of  the  trough,  and  should  be  automatic  in  its  action.  In 
most  pubUc  institutions,  but  especially  in  schools,  it  will  be  necessary  to 


THE  DWELLING 


115 


provide  a  grid  at  the  outlet  end,  to  prevent  sticks  or  other  things  improperly 
thrown  in  from  passing  into  the  drain.  A  siphon  trap  should  be  fixed  at 
the  outlet  end. 

Urinals  are  more  than  any  other  apparatus  the  cause  of  nuisance  from 
the  difficulty  experienced  in  keeping  them  clean.  This  difficulty  invariably 
arises  from  an  insufficiency  of  water.  Urine,  unless  it  is  very  copiously 
diluted,  very  quickly  deposits  its  salts  upon  all  the  surfaces  with  which  it 
comes  in  contact.  One  of  the  most  successful  forms  of  urinal  recently 
introduced  consists  of  an  earthenware  trough  formed  and  flushed  very  much 
in  the  same  way  as  a  trough  water-closet — with  a  shallower  channel  at  the 
floor,  also  constantly  flushed.  In  this  apparatus  the  urine  is  received  into  a 
large  body  of  water,  which  is  periodically  renewed  from  the  flushing  cistern, 
and  then  there  is  little  or  no  chance  of  the  surfaces  being  corroded.  In  all 
forms  of  urinal,  whether  for  pubhc  or  private  use,  it  is  important  to  provide 
that  the  urine  is  discharged  into  a  large  body  of  water,  and  that  regular  and 
automatic  flushing  is  applied  to  the  floor  surface  immediately  under  the  basin 
or  trough. 

Sinks. — The  particular  form  and  material  best  suited  for  a  sink  is 
scarcely  a  matter  which  affects  health  conditions  ;  but  in  all  sinks  the  con- 
struction and  destination  of  the  water-pipe  is  hygienically  a  matter  of  great 
importance. 

The  mode  in  which  the  waste-pipe  should  discharge  outside  the  house 
has  already  been  described.  It  is  not,  however,  sufficient  to  cause  the  waste- 
pipe  to  pass  straight  from  the  outlet  of  the  sink  into  the  open  air.  In  most 
sinks,  especially  the  scullery  ones,  a  large  quantity  of  grease  is  carried  down 
with  the  water,  and  part  of  this  is  retained  in  the  waste-pipe  and  becomes 
very  offensive,  and  the  smell  is  driven  into  the  house  by  the  cold  air  passing 
up  through  the  open  pipe.  To  remedy  this  a  lead  trap  should  be  fixed  im- 
mediately under  the  sink  ;  and  it  should  be  provided  with  a  screw  cap  either 
at  the  bottom  or  at  the  side  for  cleansing  purposes. 

In  order  to  prevent  the  grease,  which  forms  so  large  a  part  of  the  refuse 
water  sent  down  from  kitchen  or  scullery  sinks,  it  is  frequently  collected  in 
large  tanks  called  grease  traps.  The  advantage  of  this  arrangement,  espe- 
cially in  town  houses,  where  the  question  of  disposal  of  the  grease  is  by  no 
means  an  easy  one,  is  open  to  doubt.  A  better  plan  would  seem  to  be  to 
provide  a  flushing  tank  whose  contents  should  be  automatically  discharged 
with  the  trap  which  receives  the  water-pipe.  By  this  means  the  grease  is 
broken  up  and  carried  clear  away  by  the  force  of  water  behind  it,  and  has  no 
chance  of  settling  and  clogging 
the  drains. 

If  it  is  thought  desirable 
to  collect  the  grease  instead  of 
discharging  it  into  the  drains, 
a  tank  made  of  vitrified  stone- 
ware or  glazed  fireclay  pro- 
vided with  a  movable  air- 
tight cover  should  be  used. 
The  water  from  the  sinks 
should  be  discharged  through 
a  pipe  dipping  a  few  inches 
below  the  level  of  the  stand- 
ing water,  and  the  outlet  pipe  at  the  opposite  end  of  the  tank  should  be 
arranged  in  a  similar  manner.  The  grease  as  it  congeals  rises  to  the 
surface  of  the  water  and  can  then  readily  be  removed.     The  inlet  arm  of 


■VM.».^.^'AV^kV^^VKVk'.VSVVV^V.k>.>JAV'>JJJ.V^^^^ 


Fig.  161. 


776  HYGIENE 

the  tank  should  have  a  pipe  brought  up  to  the  surface  for  ventilation. 
In  order  to  empty  the  whole  contents  of  the  tank  into  the  drain,  an  outlet  is 
formed  in  the  bottom  provided  with  plug  and  washer  and  connected  with 
the  drain  by  a  pipe. 

TJie  Examination  and  Testing  of  existing  Drainage. — In  examining  the 
drainage  and  other  sanitary  appliances  of  a  house,  recourse  must  often  be 
had  to  several  modes  of  testing.  Drains  underground,  for  example,  must  be 
tested  to  ascertain  if  they  are  air-  and  water-tight,  and  this  fi-equently  has  to 
be  done  without  disturbing  the  ground.  Vertical  pipes  must  also  be  tested 
as  to  soundness,  and  the  same  test  that  is  applied  to  an  underground  drain 
cannot  always  be  applied  to  a  vertical  lead  or  iron  pipe. 

The  tests  most  commonly  applied  to  ascertain  the  condition  of  pipes  are 
water,  smoke,  and  oil  of  peppermint.  The  water  test  consists  of  filling  the 
pipes  with  water,  the  lower  end  having  first  been  securely  plugged.  This  is 
the  most  severe  test  that  can  be  applied,  and  any  drain  that  stands  the 
pressure  thus  applied  may  unhesitatingly  be  x^ronounced  sound.  The  water 
test  can  rarely  be  applied  in  old  houses  unless — which  is  seldom  the  case — a 
manhole  exists  near  the  lower  end  of  the  drain,  or  it  is  possible  to  open  the 
ground. 

The  smoke  test  can  be  applied  either  with  the  aid  of  a  pumping  apparatus 
or  by  inserting  a  '  di'ain  rocket '  into  the  course  of  the  drain.  Either  of  these 
methods  can  usually  be  applied  without  opening  the  ground  or  disturbing  the 
pipes,  but  where  the  di'ain  to  be  tested  is  underground,  and  covered  over  with 
earth  and  stone,  or  cement  paving,  the  smoke  test  often  fails  to  reveal  defects 
which  are  readily  detected  by  the  water  test.  Smoke  is  specially  useful  for 
testing  vertical  pipes,  and  for  tracing  the  source  of  smells  arising  from  defects 
in  pipes  which  are  hidden  in  walls  or  behind  casings. 

Oil  of  peppermint  is  useful  for  detecting  leaks  in  soil-pipes  or  in  drains 
where  they  are  under  wooden  floors  and  close  to  the  surface ;  but  when  once 
it  has  been  applied  its  smell  is  so  pungent  and  penetrating  that  no  second 
test  can  be  made  with  it. 

In  examining  the  condition  of  the  dramage  and  other  sanitary  appHances 
of  a  house,  the  first  process  is  to  ascertain,  as  nearly  as  possible,  the  general 
line  of  the  drainage.  Assuming  that  no  manholes  or  inspection  chambers 
are  in  existence,  it  will  be  necessary  to  dig  down  to  the  main  drain  and  open 
into  it.  The  existence  or  not  of  a  disconnecting  trap  between  the  drain  and 
the  sewer  must  next  be  ascertained,  and  if  a  trap  exists  it  is  necessary  to 
ascertain  its  form  and  construction.  The  next  step  is  to  test  the  main  drain, 
either  with  water  or  smoke,  to  ascertain  if  it  be  water-tight.  How  this 
is  to  be  done  must  depend  upon  circumstances.  Should  the  test  applied 
point  unmistakably  to  the  existence  of  leakage,  the  drain  should  be  uncovered 
for  its  whole  length,  and  the  defective  parts  traced.  All  junctions  should 
then  be  carefully  examined.  The  vertical  pipes  will  then  be  tested,  care 
being  taken  when  testing  a  vertical  pipe  with  smoke  to  cover  up  any  open 
ends.  The  waste-pipes  from  sinks,  baths,  lavatory  basins,  and  safes  under 
closets  should  next  be  examined,  and  note  made  of  any  such  pipes  which 
are  directly  connected  with  drains  or  soil-pipes.  The  overflow-pipes  from 
cisterns  must  be  traced,  and  the  supply-pipes  to  water-closets  investigated. 
Overflow-pipes  are  not  unfrequently  connected  to  soil-pipes,  and  the  water 
supply  to  a  closet  apparatus  is  often  fomid  to  be  laid  on  direct  from  the  cistern 
which  supphes  drmking  water. 


HOSPITAL    HYGIENE 


BY 


H.    G.    HOWSE,   M.S. 


SURGEON  TO  GUT'S  HOSPITAi 


HOSPITAL   HYGIENE 

In  former  days  a  permanent  unwholesomeness  of  greater  or  less  degree  was 
Jaeld  to  be  a  normal  condition  of  hospitals  inseparable  from  the  aggregation 
•of  sick  persons,  and  so  generally  did  this  view  prevail  that  the  word  '  hospi- 
talism '  was  actually  used  to  express  this  thought,  as  if  the  circumstances  of 
hospital  life  were  necessarily  prejudicial  rather  than  favourable  to  the  main- 
tenance of  health. 

Experience  has  shown  that  this  condition,  if  it  be  found  in  our  time  in  any 
institution  devoted  to  the  sick,  arises  from  one  of  two  causes,  or  from  both  : 
-either  from  the  defective  planning  or  construction  of  the  building,  or  from  mis- 
management in  its  use;  for  it  is  possible,  by  errors  in  its  administration,  for 
any  hospital,  however  well  designed,  to  become  prejudicial  to  its  inmates, 
who  are  usually  peculiarly  susceptible  to  unhealthy  influences. 

The  details  of  hospital  construction  and  constructional  arrangement  of 
wards  will  not  be  dealt  with  in  this  article,  but  in  that  headed  '  Hospitals 
and  Pubhc  Institutions,'  p.  718 ;  it  is  proposed  here  to  deal  with  minor  details 

•  of  ward-working. 

Floor  Cleaking 

The  material  of  the  floor  of  a  ward  should  be  some  fairly  hard  wood, 
prepared  so  as  to  be  non-absorbent.     Oak  is  one   of  the  best  woods,  but 

"it  is  very  expensive  ;  teak  is  also  valuable  for  the  purpose,  but  is  Httle, 
if  any,  less   expensive,  and,  though   easier  to  work,   is  not  quite  so  hard 

.  as  oak.  The  planks  forming  these  hard- wood  floors  should  be  dovetailed 
into  each  other,  or  tongued  and  grooved,  as  in  parquet  floors,  so  that  there 
may  be  no  interval  in  shrinking  between  the  planks.  It  is  best,  if  it  can 
possibly  be  managed,  to  keep  the  wood  which  is  to  form  the  flooring  of 
these  rooms  for  two  or  three  months  in  the  room  where  it  is  to  be  laid,  so 
that  all  drying  and  shrinking  may  take  place  before  laying  the  floor.  This 
is  not  often  practicable  ;  but,  in  any  case,  thoroughly  dried  and  shrunk  wood 
should  be  used,  and  the  method  of  tongued  and  grooved  floors  gives  good 
results.     They  are  not,  however,  easy  to  remove  in  case  of  necessity,  when 

.  gas  tubing,  &c.,  runs  beneath  the  floor.  This  must  be  specially  provided  for  by 
the  planks  being  screwed  simply  into  the  joints  over  the  pipes.  In  whatever 
way  the  junction  of  the  planks  is  effected,  it  is  important  that  there  should  be 

.no  space  between  the  planks  leading  to  the  interval  between  the  joists  and 
the  ceiling  of  the  room  below.  Hard-wood  floors,  after  laying,  should  be 
planed  down  level  and  then  well  sand-papered,  using  abundance  of  sand- 
paper. The  fibre  may  then  be  further  consolidated  and  rendered  waterproof 
by  using  pretty  freely  over  the  surface  a  solution  of  shellac  in  spuit.  This 
should  be  repeated  two  or  three  times,  rubbing  down  with  sand-paper  between 

•  each  application.  This  produces  an  exceedingly  hard,  durable,  and  water- 
proof floor,  which  is  as  dust-  and  germ-proof  as  it  is  possible  to  make  it. 

Deal  is,  however,  the  commonest  material  of  which  the  floors  of  hospital 
wards  are  constructed,  both  on  account  of  its  price  and  of  its  ease  of  working. 
It  is  therefore  necessary  to  consider  the  best  mode  of  treating  it  in  all  the 
-  hospitals  in  which  it  already  forms  the  material  used. 


780  HYGIENE 

If  the  better  forms  of  deal  be  used,  not  much  objection  can  be  raised  to 
it,  especially  if  some  special  modes  of  preparation  and  hardening  are  made 
use  of.  The  inferior  and  softer  kinds  of  deal  are  objectionable,  in  that  they 
become  exceedingly  porous  and  absorbent  after  much  washing,  and  thus 
afford  a  basis  for  absorption  of  decomposing  discharges,  and  even  of  foul 
odours. 

As  a  rule,  in  our  hospitals  much  too  little  attention  is  paid  to  the  condi- 
tion of  the  floors.  If  deal  be  used,  it  commonly  shrinks  considerably  for 
some  time  after  it  is  laid  down,  even  when  the  quality  of  the  wood  is  good, 
leaving  long  fissures  between  the  planks.  These  fissures  at  first  allow  a 
great  accumulation  of  dust,  dirt,  and  flue  to  collect  between  the  boards  and 
the  ceiling  of  the  room  below  ;  and  this  can  never  be  got  at  and  removed. 
If  the  fissures  remain  open,  this  dust  is  liable  to  be  blown  up  into  the  ward 
in  a  high  wind,  if  the  space  below  the  flooring  is  properly  ventilated  (for  the 
prevention  of  dry  rot).  This  dust  is  often  a  means  of  re-infection,  after  the 
closure  and  most  careful  cleansing  and  painting  of  a  ward.  Gradually,  how- 
ever, after  a  considerable  lapse  of  time  these  fissures  tend  to  become  closed, 
at  any  rate  in  all  the  more  trodden  parts,  by  a  collection  of  dirt  and  debris 
in  them.  This  is  only  a  less  objectionable  condition  than  the  open  state,  if 
the  flooring  be  regularly  washed.  The  collection  of  dirt  in  them,  being  con- 
tinually wetted,  forms  a  nidus  of  germ-growth  which  cannot  but  be  regarded 
as  undesirable.  These  fissures  should  be  stopped  in  some  way  within  three 
or  four  years  of  the  first  laying  down  of  the  floor  (or  at  a  later  period) 
with  some  non-absorbent  material.  This  is  best  and  most  easily  done  by  thin 
strips  of  wood  laid  and  glued  into  the  fissures.  If  the  flooring  has  been 
stained  and  polished  from  the  first,  the  fissures  will  probably  have  been 
closed  by  cement  worked  into  them.  This  cement  is  usually  some  form  of 
putty  of  the  same  tint  as  the  flooring,  and  mixed  with  the  same  gum- 
resinous  varnish  as  that  used  for  the  floor.  This  is  good,  if  the  fissures  be 
small ;  but  when  they  become  wide  and  gaping,  the  cement  should  be  cleaned 
out  and  strips  of  wood  substituted. 

As  far  as  the  healthy  condition  of  the  ward  is  concerned,  the  writer 
believes  that  the  stained  and  polished  floor  is  far  better  than  one  which  has  to 
be  continually  washed.  Objection  is  occasionally  raised  that  the  cleansing 
of  such  polished  floors  is  a  process  of  '  rubbing  the  dirt  in.'  There  is  not 
much  force  m  the  objection.  A  properly  prepared  polished  floor  leaves  little,, 
if  any,  space  for  '  rubbing  dirt  in.'  And  the  writer,  for  his  part,  would  far 
sooner  do  operations  in  a  ward  of  which  the  flooring  is  kept  clean  and 
poUshed  than  in  one  where  the  cleanliness  is  obtained  by  continual  washing. 

In  the  preparation  of  a  deal  floor  for  staining  and  polishing,  after  filling 
aU  the  cracks  and  fissures  vnth  strips  of  wood  and  cement,  it  should  be  well 
rubbed  down  with  abundance  of  sand-  or  glass-paper.  This  process  adds 
very  much  to  the  hardness  of  the  floor.  In  doing  it,  minute  particles  of  the 
sand  or  glass  get  rubbed  off  and  embedded  in  the  woody  fibre. ^     If,  now,  this 

'  It  is  not  generally  known  how  very  much  this  adds  to  the  hardness  of  a  wood.  In 
wood  turned  and  polished  with  sand-paper  on  the  lathe,  if  any  ornamentation  has  to  be 
afterwards  added,  it  is  found  that  wood  so  polished  takes  oS  the  edge  of  the  fine-steel 
tools  used  in  the  process  very  much  more  quickly  than  the  original  wood,  on  account  of 
the  particles  of  silica  embedded  in  the  fibre. 

Some  years  ago  the  floors  of  the  wards  in  Guy's  Hospital  were  cleaned  with  sand. 
This  was  good  for  the  boards,  but  it  had  to  be  given  up,  because  with  the  open  fissures  be- 
tween the  boards  such  a  quantity  of  sand  gradually  accumulated  on  the  top  of  the  ceiling 
below,  that  sooner  or  later  the  ceiling  gave  way  from  the  weight,  and  fell  in  great  pieces  into 
the  ward  below.  With  tongued  and  grooved  flooring,  however,  this  need  never  take  place. 
It  is  probable  that  the  sand-scrubbed  flooring  of  the  past  generation  was  much  more- 


HOSPITAL  HYGIENE  781 

surface  be  brushed  over  once  or  twice  with  a  solution  of  shellac  in  spirit  of 
wine,  and  in  the  interval  between  each  application  rubbed  again  with  fine 
sand-paper,  it  will  be  found  that  even  deal  can  be  so  much  hardened  and 
rendered  so  resisting  as  to  become  a  very  durable  material. 

Such  floors,  whether  they  are  of  deal  or  hard  wood,  may  be  polished  and 
Tiept  clean  by  being  rubbed  with  a  mixture  of  turpentine  and  beeswax  (in 
the  proportion  of  one  pint  to  a  quarter  of  a  pound,  melted  together).  But  in 
the  case  of  deal,  it  is  well  occasionally  to  repeat  the  application  of  the 
spirituous  solution  of  shellac,  say,  once  a  year,  so  as  to  maintain  the  fibre  of 
a  proper  degree  of  hardness. 

Walls 

The  walls  of  a  ward  should  be  of  hard  plaster,  capable  of  being  well  rubbed 
•down  and  polished.  No  inequalities  or  cracks  should  be  allowed  to  exist. 
The  surface  of  the  wall  should  be  painted,  so  that  it  can  be  periodically 
washed,  the  paint  being  left  with  its  oil  (i.e.,  shiny)  surface,  and  not '  flatted.' 
'Or  it  may  be  covered  with  a  coat  of  varnish.  The  cornice  mouldings  should 
be  of  the  fewest  and  most  simple  description,  or  altogether  absent,  so  as  to 
present  as  few  angles  and  recesses  for  the  lodgment  of  dust  as  possible.  If 
wood  wainscoting  or  panelling  is  used,  it  should  be  of  hard  wood,  and  should 
be  of  the  simplest  possible  description,  with  plain  or  rounded  surfaces,  and  as 
few  angles  as  possible.  The  surface  should  be  treated  in  the  same  manner 
as  that  already  given  for  the  flooring.  With  the  exception  of  the  skirting 
board,  which  saves  the  wall  from  breaking  low  down  from  careless  blows, 
wood  is  a  very  doubtful  material  for  the  construction  of  the  walls,  unless 
used  absolutely  plain.  The  tendency  always  is  to  ornament  wood  used  in 
the  construction  of  a  wall,  either  by  panelling  or  even  carving,  and  this  is  not 
advisable. 

The  surface  of  a  polished  plaster  wall  should  be  washed  down  periodically 
{at  any  rate,  once  in  three  months)  with  warm  soap  and  water.  If  there 
have  been  any  doubtful  cases  in  the  ward,  it  is  well  to  use  a  solution  of 
carbolic  acid  (about  1  in  30)  instead  of,  or  in  addition  to,  the  soap  and 
water.  If  it  can  possibly  be  managed,  it  is  well  to  apply  one  thin  coat  of 
paint  once  a  year.  This  is  better  than  allowing  a  longer  time  to  elapse  and 
then  applying  two  or  three  coats  at  once.  It  keeps  the  walls  and  wood- 
work in  better  condition,  and  provides  for  the  stopping  of  any  cracks  or  fissures 
■which  may  be  appearing. 

The  same  principles  should  be  applied  as  regards  any  pictures  or  other 
ornaments  hung  on  the  walls.  As  a  rule,  pictures,  brackets  for  statuary,  and 
other  similar  ornaments,  form  a  nidus  for  dust,  which  is  objectionable.  On 
the  other  hand,  they  cannot  be  altogether  excluded  from  a  ward,  as  they  give 
an  air  of  cheerfulness  and  home  comfort  which  must  be  conducive  to  the 
well-being  of  the  patients.  Pictures,  therefore,  should  have  the  simplest 
possible  frames,  and  should  be  glazed,  so  that  they  can  be  easily  dusted  and 
kept  clean.  They  should  be  hung  with  picture  wire,  not  cord,  which  attracts 
the  dust.  The  same  rules  should  be  observed  as  regards  texts  or  any  other 
ornaments  used  about  the  walls. 

The  method  adopted  in  the  Johns  Hopkins  Hospital  at  Baltimore,  U.S.A., 
of  joining  the  walls  with  the  floor  by  a  concave  moulding,  so  as  not  to  allow 

durable  than  the  soap-washed  one  of  the  present.  Continual  soap-washing,  where  there 
is  much  treading,  tends  to  a  separation  of  the  bundles  of  woody  fibre  from  each  other  in 
a  deal  floor.  This  may  be  seen  in  any  of  the  soap-washed  deal  floors  in  our  older 
hospitals,  and  accounts  for  the  ragged  appearance  which  they  often  present. 


782  HYGIENE 

any  angle  to  exist  for  the  accumulation  of  dust  (which  is  with  difficulty  re- 
moved by  a  broom  from  the  usual  corner  between  the  skirting  board  and  the 
floor),  is  one  worthy  of  imitation,  but  has  been  only  rarely  adopted  in  this 
country.  The  same  principle  may  be  applied  to  the  angle  between  the  wall 
and  the  ceiling. 

In  temporary  hospitals  and  those  in  which  cheapness  is  a  great  object, 
the  walls  are  fi-equently  white-limed.  This  produces  a  rough  wall,  liable  to 
become  dirty  in  all  the  parts  within  reach,  and  therefore  requiring  frequent 
renewal.  The  coating  of  hme,  also,  soon  loses  the  antiseptic  quality  which 
makes  it  so  excellent  a  material  for  use  for  short  periods.  It  is  therefore  not 
well  adapted  for  the  walls  of  permanent  hospitals.  On  the  other  hand,  for 
ceilings  its  superior  whiteness  makes  it  a  more  desirable  material  than  paint. 
Such  surfaces  can  be  readily  renewed  once  a  year,  and  though  the  roughness 
is  an  imdesirable  quahty,  yet  the  bright  appearance  which  a  frerihly  white- 
limed  ceiling  gives  to  a  ward  adds  to  its  cheerfulness  and  consequently  to 
its  healthiness. 

The  Beds 

All  bed  linen  should  be  frequently  changed.  Though  no  rules  can  be 
laid  down  how  frequently  this  may  be  necessary,  yet  it  may  be  roughly  stated 
that  it  should  be  done  once  a  week  in  every  case,  and  very  much  more 
frequently  in  those  in  which  the  secretions  or  discharges  are  abundant  or 
offensive.  The  woollen  blankets  and  coverlets  should  also  be  frequently 
washed  and  aired,  or  even  baked  at  a  dry  heat  of  300°  Fahr.,  if  the  case  is 
a  doubtful  one.  All  dirty  linen  should  be  stored  in  covered  baskets  outside 
the  wards,  or  in  closed  tin-lined  boxes  inside  the  ward,  if  there  are  no  con- 
veniences for  storage  outside  the  ward.  The  former  plan  is  best,  because  it 
permits  free  access  of  air  to  the  dirty  linen.  The  boxes  or  baskets  should  be 
emptied  every  day,  and  the  contents  taken  to  the  laundry,  where  they  should 
first  be  disinfected  by  being  placed  in  a  large  tank  of  antiseptic  fluid.  If 
they  be  very  dirty,  or  much  soiled  with  blood  or  discharges,  a  previous  soak- 
ing in  pure  water  is  best.  The  use  of  solution  of  carbolic  acid  or  any  other 
antiseptic  for  the  first  soaking  tends  often  to  set  the  discharge  in  the  fibre  of 
the  material,  and  thus  to  render  more  difficult  the  subsequent  cleaning.  This 
is  often  the  cause  of  the  complaints  made  ahke  by  Sisters,  nurses,  and  patients 
against  hospital  linen,  viz.,  that  it  does  not  return  so  clean  and  white  from  the 
wash  as  the  home  linen  does.  The  clean  linen  for  the  beds  is  brought  into 
the  wards  once  or  twice  a  week,  and  may  be  safely  stored  in  cupboards  or 
boxes  within  the  wards. 

Draw-sheets  and  macintoshes  used  to  protect  the  bed  should  especially  be 
frequently  changed,  and  it  is  questionable  whether  it  is  advisable  to  mix 
draw-sheets  from  offensive  cases  with  the  other  bed  linen  from  the  ward. 
The  macintoshes  should  be  those  macintoshed  on  both  sides,  so  as  to 
present  a  smooth,  shiny  surface  on  either  aspect.  These  can  be  easily 
washed  and  purified,  and  are  besides  much  more  durable  and  economical. 
Those  macintoshed  between  two  layers  of  cotton  stuff,  and  thus  presenting 
the  rough  cotton  fibre  texture  externally,  are  very  objectionable.  They  easily 
become  stained  and  dirty,  and  are  difficult,  if  not  impossible,  to  purify. 

Splints  used  in  surgical  cases  must  be  carefully  washed  and  purified  after 
use.  Those  of  wood  should  be  washed  with  a  solution  of  corrosive  sublimate 
and  occasionally  rubbed  over  with  fine  sand-paper.  With  these  precautions, 
the  splints  do  not  now  become  infested  with  vermin  as  they  used  to,  even 
as  recently  as  twenty  years  ago.      Consequently,  there  is  no  necessity  for 


HOSPITAL  HYGIENE  783 

using  any  medicated  wool  for  the  pads  of  these  splints,  and  plain  cotton 
wool  or  tow  is  the  material  generally  used.  Oakum  or  tenax,  which  was 
formerly  much  used,  stains  the  splints,  and  often  the  bed  linen,  by  reason  of 
the  tarry  material  contained  in  it  soaking  through.  These  materials  are  not 
therefore  now  much  in  favour,  and  the  necessity  for  them  has  mostly  dis- 
appeared since  the  careful  purification  of  the  splints.  Nevertheless,  any  pad 
may  become  accidentally  infected  from  the  patient's  clothing,  especially  in 
a  case  of  accident,  and  hence  these  pads  should  be  changed  as  frequently  as 
opportunity  permits,  and  always  burnt  directly  after  use. 

The  bedsteads  should  of  course  be  of  iron,  painted  or  enamelled,  so  that 
they  can  be  easily  kept  clean.  Wire-woven  mattresses  are  now  much  more 
frequently  used  than  formerly,  though  the  ancient  sacking,  if  kept  sufficiently 
tight,  is  not  a  material  to  be  despised.  It  gives  a  certain  springiness  (as  in 
hammock  beds),  and  is  a  material  easily  changed  and  purified.  For  fracture 
beds,  boards  placed  below  the  mattress  are  necessary,  but  they  should  be 
washed  with  a  solution  of  corrosive  sublimate  occasionally  to  prevent  the  old 
trouble  (inherent  in  all  wooden  structures)  of  their  becoming  infested  with 
vermin.  The  mattresses  and  beds  are  usually  stuffed  with  flock,  and  this  is 
probably  the  best  material  that  can  be  used  in  all  large  hospitals  where 
expense  has  to  be  considered.  It  has  the  advantage  of  being  a  cheap  material, 
and  the  beds  are  very  easily  purified  and  restuffed. 

Flock  beds  can  be  changed  if  necessary  with  every  new  patient,  and  the  old 
bed  sent  to  be  cleansed  and  disinfected  by  superheated  steam  at  a  tempera- 
ture of  300°  or  350°  Fahr.  The  flock  is  generally  hand-picked  through 
before  this,  and  any  very  bad  pieces  not  easily  cleansed  are  removed  and 
destroyed.  Hence  the  advantage  of  a  cheap  bedding  material.  Hair  mat- 
tresses, as  a  rule,  though  better  for  many  cases,  are  too  expensive  both  in 
material  and  working  (when  they  have  to  be  disinfected)  for  general  use. 
A  hair  mattress,  if  it  has  to  be  disinfected,  has  to  be  pulled  entirely  to  pieces 
to  accomplish  the  process  satisfactorily.  Attempts  have  been  made  at  various 
places  to  disinfect  a  hair  mattress  en  masse  by  subjecting  it  for  a  long  period 
to  both  dry  and  moist  heat  at  a  temperature  of  350°  F.  It  has  been  found 
that  such  a  long  exposure  is  necessary  in  order  to  penetrate  adequately  the 
structure  of  the  mattress,  and  that  the  texture  becomes  greatly  damaged  in  the 
process.  Hence  this  mode  of  disinfection  has  been  abandoned.  The  pick- 
ing to  pieces  of  a  hair  mattress  and  re-stuffing  it  is  a  much  more  expensive 
process  than  with  the  flock  bed  (to  say  nothing  of  the  difference  in  the 
original  cost  of  the  material),  and  hence  we  have  a  very  powerful  argument 
in  favour  of  the  flock.  If,  however,  for  any  reason  hair  mattresses  are  used, 
the  plan  adopted  at  the  General  Lying-in  Hospital,  referred  to  later  on 
{vide  p.  802) — of  having  a  register  of  mattresses,  each  one  ticketed  and 
numbered,  and  only  sent  away  for  purification  when  any  doubtful  case  has 
occurred  with  it — is  a  good  one. 

Dresses  of  Attendants 

The  Sisters  and  nurses  should  be  dressed  in  some  washable  material. 
In  general  hospitals  clerks  and  dressers  will  usually  wear  their  ordinary 
woollen  clothing ;  and  the  medical  attendants  in  England  almost  invariably 
do  the  same.  In  many  of  the  Continental  hospitals,  however,  the  medical 
staff  change  their  outer  clothes  on  the  visit  to  the  wards  to  a  suit  of  some 
washable  material.  In  operating,  again,  there  is  very  great  variety  of  practice 
amongst  surgeons  even  in  England.  Some  assume  a  special  operating  dress 
of  washable  material ;  others  a  special  macintoshed,  shiny  garment,  which  can 


784  HYGIENE 

be  easily  washed  down  and  pm-ified.  The  great  majority  of  English  surgeons 
continue  to  wear  an  ordinary  woollen  operating  coat,  with  perhaps  a  mac- 
intosh apron  and  sleeves.  At  the  present  time  there  is  a  tendency  in  favour  of 
the  Continental  plan,  viz.,  to  adopt  some  washable  material  for  operating  in. 
The  writer  is  of  opinion  that  the  use  of  this  will  depend  in  the  future  very 
much  upon  whether  the  carbolic  spray  is  retamed  or  discarded  in  practice. 
If  it  is  retained,  he  thinks  that  the  woollen  coat  becomes  absolutely  innocuous 
by  constant  use  in  it.  The  sleeves  and  every  other  part  become  so  impreg- 
nated with  carbohc  acid  in  vapour  and  solution,  that  practically  the  blood 
which  gets  on  to  the  garment  dries  without  decomposing.  This  may  be 
shown  by  mixing  blood  and  carbolic  lotion  (1  in  30),  or  even  pus  and  carbolic 
lotion,  together,  and  spreading  them  out  in  a  fairly  thin  layer  to  dry.  The 
mixture  di'ies  into  a  leathery  material,  composed  of  coagulated  albumen, 
fibrin,  blood-corpuscles,  &c.,  which  refuses  to  decompose  in  the  ordinary  sense 
of  the  term.  No  doubt  it  undergoes  chemical  change,  but  not  of  a  kind 
prejudicial  to  subsequent  operations.  Even  offensive  cases,  e.g.,  cases  of  de- 
composing pus  in  abscesses  such  as  occur  in  urmary  or  faecal  abscesses,  may 
be  operated  on  safely  with  an  abundant  carbolic  spray  (used  as  an  irrigant) 
in  such  a  garment.  But  the  treatment  of  such  patients  comes  under  the 
head  of  infectious  cases,  rather  than  under  that  of  ordinary  aseptic  surgery. 
Still,  every  surgeon  must  necessarily  treat  such  cases  in  the  course  of  ordi- 
nary practice,  and  often  in  wards  mixed  with  other  patients.  If  obliged 
to  do  so,  he  will  naturally  put  off  such  cases  to  the  last,  and  he  will  be  care- 
ful not  to  use  the  coat  again  imtil  it  has  been  thoroughly  aired  and  dried, 
i.e.,  for  at  least  twenty-four  hours.  With  these  precautions,  the  writer  has 
never  seen  any  mischief  result  from  the  use  of  the  ordinary  woollen  coat. 
In  our  variable  climate  the  use  of  this  garment  is  so  much  more  comfortable, 
so  much  warmer  and  safer  for  the  operator,  as  compared  with  the  thin, 
washable,  generally  linen  or  cotton  garment  usually  substituted  for  it,  that 
its  use  will  probably  be  generally  maintaine  d. 

On  the  other  hand,  if  the  carbolic  spray  is  given  up,  the  vsriter  is  of 
opinion  that  there  is  increased  need  for  the  washable  garment,  whether  it 
be  of  linen  or  macintosh,  both  for  operator  and  for  dressers.  In  these  cases 
asepsis  is  generally  maintained  either  by  continuous  irrigation  during  the 
operation  from  a  large  syringe  or  cistern,  or  by  washing  the  wound  out  after 
the  operation  is  over.  For  reasons  given  subsequently  {vide  note,  p.  788) 
the  writer  regards  neither  of  these  alternatives  as  perfect.  And,  as  far  as 
the  dress  of  the  operator  and  his  assistants  is  concerned,  they  are  absolutely 
ineffectual.  The  air  is  no  longer  full  of  a  fine  antiseptic  rain  ;  there  is  no 
wetting  of  the  clothes ;  and  though  this  may  slightly  contribute  to  the  comfort 
of  those  about,  yet  the  risk  must  be  very  perceptibly  increased.  For  these 
reasons  the  tendency — very  visible  during  the  last  year  or  two  amongst  those 
surgeons  who  have  abandoned  the  use  of  the  carbolic  spray — to  adopt  a 
special  washable  dress  for  operating  in  must  be  regarded  as  a  good  one. 
But  if  the  rule  is  to  be  effectual,  it  must  be  extended  to  the  assistants  as  well 
as  to  the  operator  himself. 

In  very  septic  operations,  and  aU  those  performed  on  infectious  cases  in 
isolation  wards,  a  special  external  suit  of  clothing  should  be  worn,  which 
should  be  kept  solely  for  this  purpose.  In  isolation  hospitals,  or  wards  of 
large  size,  where  many  infectious  cases  are  associated  together,  this  rule 
should  be  extended  to  the  visit  also.  This  applies,  of  course,  to  dressers  and 
house  surgeons  as  well  as  to  the  visit  of  the  medical  or  surgical  staff. 


HOSPITAL  HYGIENE  785 

Visits  op  Friends  to  Patients 

There  can  be  no  doubt  that,  though  in  all  large  general  hospitals  it  is 
absolutely  necessary  to  allow  these  visits,  they  yet  introduce  a  very  consider- 
able element  of  risk  into  the  sanitation  of  the  ward  and  into  the  treatment 
of  the  patients.  On  several  occasions  the  writer  has  seen  infectious  diseases 
brought  into  hospitals  by  visitors  coming  from  infected  homes.  There  seems 
absolutely  no  practical  or  workable  plan  of  preventing  this.  It  is  no  use 
questioning  the  visitors  before  admission.  Their  eager  desire  to  see  their 
relatives  or  friends  in  the  hospital,  or  their  crass  ignorance  as  regards  what 
constitutes  an  infectious  malady,  makes  them  either  regardless  of  the  truth 
or  misleading  in  the  expression  of  facts.  Moreover,  it  is  not  possible  to  ex- 
clude the  relatives  from  hospitals  or  wards  where  surgical  operations  have  tO' 
be  performed,  because  were  this  done  a  cry  would  speedily  arise,  especially 
in  cases  which  terminated  unsuccessfully,  that  the  patient  had  not  been 
treated  well,  that  barbarities  had  been  practised,  &c.,  &c. — unfounded  rumours- 
such  as  have  been  propagated  many  years  ago,  either  by  ignorant  or  malicious- 
persons,  in  respect  to  many  hospitals.  Such  rumours  and  unfounded  accusa- 
tions can  only  be  prevented  by  allowing  the  relatives  and  friends  moderately 
free  access  to  the  patients  during  their  treatment.  The  great  confidence 
with  which  the  public,  both  educated  and  ignorant,  now  treat  our  general 
hospitals — a  confidence  which  even  the  violent  and  widely  spread  slanders  of 
anti-vivisectionists  and  other  fanatics  have  failed  to  shake — is  largely  due  to 
the  friends  and  relatives  being  allowed  to  see  patients,  and  thus  to  form  some 
idea  for  themselves  how  they  are  progressing,  and  how  they  are  treated. 
Still  this  introduces  an  element  of  risk  from  the  cause  mentioned,  and  it  is 
a  subject  of  anxious  consideration  how  far  these  risks  may  be  minimised 
without  altogether  preventing  the  visits.  In  all  general  hospitals  of  late 
years  a  tendency  to  diminish  the  number  and  length  of  the  visiting  has  been 
apparent.  Thus  at  Guy's  Hospital  there  used  to  be  three  visiting  days  a 
week  ;  now  there  are  only  two.  At  the  Evelina  Hospital  for  Sick  Children 
there  used  to  be  two,  but  now  there  is  only  one  day  a  week.  And  in  both 
hospitals  the  number  of  visitors  to  each  patient  has  been  strictly  hmited  of 
late  years.  Thus  at  Guy's,  not  more  than  three  visitors  are  admitted  at 
once  to  see  the  patient ;  at  the  Evelina  only  one  at  a  time.  It  will  be  seen- 
that  the  rule  is  much  stricter  in  the  children's  hospitals  than  in  the  adult. 
This  has  arisen  from  necessity,  on  account  of  the  much  greater  risk  of  im- 
porting infectious  diseases  amongst  many  children  congregated  together  than 
amongst  adults.  The  writer  has  seen  on  so  many  occasions  measles  and 
scarlatina  break  out  in  children's  wards  after  the  visit  of  some  friend  or  relative 
from  an  infected  home,  and  the  results  are  so  disastrous,  especially  in  surgical 
wards  where  nearly  all  surgical  operations  have  to  be  suspended  during  the 
epidemic,  and  the  ward  practically  closed — at  any  rate  to  all  fresh  patients — 
that  it  would  appear  as  if  no  rule  were  too  strict  to  prevent  the  occurrence  of 
these  outbreaks.  It  is  for  this  reason  that  the  number  of  visiting  days  each 
week  is  restricted  to  one,  and  that  only  one  friend  at  a  time  is  admitted  to 
see  the  patient.  Even  with  this  amount  of  visiting,  epidemics  still  some- 
times occur.  And  it  must  be  manifest  that  they  could  never  be  entirely 
prevented,  even  were  the  friends  excluded  altogether,  because  there  is  always 
the  risk  of  a  fresh  child  being  admitted  to  the  ward  from  an  mfected  home, 
the  previous  surroundings  of  each  freshly  admitted  patient  being  of  course 
quite  unknown. 

In  isolation  hospitals  it  is  the  rule  not  to  admit  any  friend  to  see  the 
patient  during  his  residence  in  the  hospital,  and  it  must  be  manifest  that  no 

VOL.   I.  3  E 


786  HYGIENE 

relaxation  of  this  rule  could  in  any  way  be  permitted  without  the  risk  of 
spreading  contagion,  at  any  rate  in  the  majority  of  infectious  diseases 
.admitted  into  these  hospitals. 

Patients'  Clothing 

The  clothes  in  which  a  patient  is  admitted  into  hospital  must  be  treated 
according  to  the  state  in  which  they  are  found.  If  very  dirty,  they  should 
be  sent  back  home  by  the  patient's  friends.  This  would  be  the  best  plan  in 
.all  cases,  and  is  indeed  adopted  at  certain  small  special  hospitals ;  but  in 
large  general  hospitals  it  has  been  found  that  the  sending  for  the  clothes 
involves  so  much  delay  when  it  is  desired  to  discharge  the  patient,  especially 
when  the  friends  do  not  particularly  wish  to  have  him  home,  that  some  plan 
of  keeping  the  clothes  becomes  absolutely  necessary  for  the  good  working  of 
the  hospital.  This  is  best  done  by  keeping  each  patient's  clothes  in  separate 
bundles  in  large  closets  outside  the  ward.  Each  bundle  should  be  separated 
from  the  others  by  a  wooden  or  metallic  partition,  which  can  be  easily  taken 
out,  and  the  whole  place  frequently  washed  out.  If  wooden  shelves  and 
partitions  are  used,  they  should  be  wetted  with  a  solution  of  mercuric 
chloride  before  being  replaced,  so  as  to  prevent  vermin.  If  the  patient's  stay 
in  hospital  is  likely  to  be  a  long  one,  soiled  linen,  &c.,  had  better  be  washed 
before  being  put  away,  and  if  there  be  a  suspicion  of  vermin,  the  clothes 
should  be  subjected  to  the  dry-heat  process  before  being  placed  in  the  closet. 
Indeed,  in  some  hospitals  this  is  done  with  nearly  all  the  clothes  which  are 
kept.  And  it  must  be  admitted  that  this  question  of  patients'  clothes  is 
often  one  giving  much  trouble,  and  requiring  a  good  deal  of  discretion  on 
the  part  of  the  Sisters  and  nurses.  The  closets  and  trays  especially  require 
continual  overhauling,  to  see  that  everything  is  kept  as  clean  and  un- 
objectionable as  possible. 

The  clothes  of  a  patient  suffering  from  an  infectious  disorder  must,  of 
course,  be  thoroughly  disinfected  and  cleansed  by  one  of  the  methods 
mentioned  elsewhere  before  being  put  away.  Such  clothing  should  be  kept 
by  itself,  and  not  allowed  to  mix  with  that  from  ordinary  patients. 

The  writer  does  not  here  refer  to  the  clothing  to  be  worn  by  the  patient 
during  his  stay  in  the  hospital.  This  will  of  course  vary  according  to  the 
nature  of  the  case.  In  a  few  hospitals  it  is  pro\dded  by  the  institution 
itself,  but  in  large  hospitals  more  generally  (and  in  the  writer's  opinion  more 
suitably)  by  the  patient  himself.  Still,  if  the  patient  be  very  poor,  it  may 
be  necessary  to  provide  more  or  less  clothing  in  this  way.  And  in  most 
children's  hospitals  in  Tjondon  a  certain  amount  of  the  patients'  clothing 
while  in  bed  is  almost  invariably  provided  by  the  institution — perhaps  more 
to  give  a  pleasing  unifui-uiity  to  the  ward  than  with  any  actual  charitable 
intent. 

LOCKEES 

In  nearly  every  hospital  there  is  provided  for  each  bed  a  locker,  which 
serves  partly  as  a  table,  partly  as  a  small  cupboard  in  which  patients  can 
place  things.  Though  in  most  hospitals  it  is  regarded  as  an  almost  neces- 
sary adjunct  to  the  bed,  conducing  to  the  comfort  of  the  patient  and  to  the 
tidiness  of  the  ward,  yet  it  is  one  of  the  most  doubtful  articles — hygienically 
considered — which  a  ward  can  contain.  It  is  sometimes  used  for  food,  some- 
times for  articles  of  dress,  books,  &c.,  sometimes  as  a  receptacle  in  which  the 
small  pot  used  for  urine  or  expectoration  is  hidden  away.  Nothing  can  be 
nastier  than  this  combined  use  of  the  same  receptacle,  even  though  it  may 
take  place  at  different  times.     Those  who  kno^v  the  pecuhar  saturating  effect 


HOSPITAL  HYGIENE  19,1 

which  a  pot  of  warm  urine  has  upon  a  commode,  however  carefully  painted 
(or  polished  if  of  a  hard  wood)  its  interior  may  be,  will  understand  what  the 
Writer  means.  Good  housewives  even  object  in  a  well-ordered  bedroom 
to  the  pot  de  chambre  being  placed  after  use  under  the  bed,  especially  if 
the  bed  has  a  steel  spring  mattress,  on  account  of  the  gradual  rusting  effect 
of  the  vapour  arising  from  the  warm  urine  on  the  metal.  If,  therefore,  one 
patient  uses  his  locker  for  urine,  it  will  be  impure  always  afterwards, 
unless  repainted  in  its  interior.  The  greatest  vigilance  of  the  nurses  is 
unequal  to  meet  this  abuse.  The  writer  has  seen  surreptitious  food  stuffed 
into  these  lockers  during  visiting  hour  removed  by  the  nurse  examining  the 
locker  after  the  visit  was  over,  and  yet  an  hour  or  two  later  more  food  has 
heen  found  in  the  locker.  Many  of  the  patients  act  in  ignorance  of  the 
rules  existing  in  most  hospitals  on  this  subject.  Many  more  act  in  wilful 
defiance  of  these  rules,  and  nearly  all  are  quite  ignorant  that  these  rules 
.are  made  for  their  own  protection  and  good.  It  is  not  easy  to  see  how  the 
evil  can  be  remedied,  except  by  the  complete  abolition  of  the  closed  locker 
and  the  substitution  for  it  of  a  small  table  with  open  shelves  below,  where- 
•on  the  nurses  or  Sister  can  see  at  a  glance  everything  they  contain.  In 
the  furnishing  of  all  new  hospitals  it  is  to  be  hoped  that  the  locker  of  the 
future  will  take  this  form.  It  will  involve  some  sacrifice  of  tidiness,  but 
this  will  have  far  more  than  compensating  advantages.  Even  upon  the 
shelves  of  these  tables  the  urine  pot  should  not  be  placed.  Every  urine 
receptacle  should  have  a  small  painted  wooden  or  metal  cover  closely 
fitting  to  the  top,  and  it  should  be  a  rule  of  the  ward  that  this  cover  should 
be  applied  directly  after  use.  The  pot  may  then  be  placed  safely  below  the 
bed  or  upon  a  special  shelf  on  the  wall  near  the  bed.  But  with  the  cover 
there  is  really  no  objection  to  its  being  placed  under  the  bed.  During  the 
time  of  cooling  of  the  urine  any  steam  arising  condenses  on  the  cover,  and 
all  harmful  effects  on  the  bed  are  prevented.  The  cover  also  excludes  dust, 
&c.,  from  the  urine,  and  thus  renders  its  chemical  examination  afterwards 
(should  that  be  necessary)  so  much  the  more  satisfactory.  As  far  as  expec- 
toration is  concerned,  nothing  can  be  better  than  the  small  earthenware  pots 
with  funnel  covers  in  use  in  the  wards  of  most  London  hospitals.  In  the 
case  of  fffical  excreta,  it  need  scarcely  be  added  that  of  course  they  should  be 
removed  as  soon  as  passed,  and  that  it  is  always  desirable  to  keep  a  small 
quantity  of  some  rapidly  deodorising  solution  in  bedpans,  slippers,  &c.,  so 
as  to  mitigate  the  nuisance  of  smell  in  a  ward  where  the  patient  is  obliged 
to  relieve  himself  in  bed. 

The  keeping  of  food  in  lockers  cannot  be  too  strongly  deprecated.  In 
some  hospitals  it  is  the  custom  to  give  out  the  day's  allowance  of  bread, 
butter,  milk,  &c.,  to  the  patient  in  the  morning,  and  this  is  kept  in  the  locker 
till  consumed  or  taken  away.  For  the  reasons  given  above,  this  should 
never  be  allowed.  All  food  should  be  kept  under  one  common  control, 
should  be  served  out  fresh  to  each  patient  at  the  meal  time,  and  the 
remnants  taken  away  afterwards.  Nothing  can  be  worse  for  the  sweetness 
and  freshness  of  the  food  than  the  constant  standmg  of  small  quantities  of 
unconsumed  food  (such  as  bread,  milk,  &c.),  whether  in  or  outside  a  locker, 
hy  the  patient's  bedside  all  day.  Nothing  can  more  surely  tend  to  the  taking 
away  of  what  appetite  he  may  have  than  the  constant  sight  of  such  food.  In 
many  hospitals,  again,  it  is  the  rule  for  patients  to  provide  their  own  grocery. 
Even  this  is  to  be  deprecated.  But  where  the  poverty  of  the  hospital  resources 
renders  this  absolutely  necessary,  it  is  best  that  the  grocery  should  be  placed 
in  a  small  drawer  in  the  table — a  drawer  too  small  and  too  shallow  to  contain 
urine  or  any  objectionable  article. 

3e2 


788  HYGIENE 

Dkessings 

Dressings  are  best  kept  in  a  ward  in  a  cupboard  or  box  by  tbemselves.. 
A  movable  table  (running  on  wbeels  witb  indiarubber  tires),  fitted  -vsath 
drawers  and  small  cupboards,  is  tbe  best  receptacle  for  tbe  day's  dressings. 
Antiseptic  dressings,  wbere  tbe  dressing  contains  a  vaporisable  cbemical  (as 
carbolic  acid,  oil  of  eucalyptus,  or  iodoform),  sbould  be  kept  in  an  air-tight  tin 
or  tin-lined  box  in  tbe  table.  This  is  not  of  so  much  importance  wbere  tbe 
antiseptic  is  fixed,  as  in  sal-alembroth  gauze  and  wool  (corrosive  sublimate). 
But  even  here  tbe  material  sbould  be  all  kept  together,  packed  away  tightly, 
so  as  to  exclude  dust  as  much  as  possible. 

In  many  wards  devoted  to  purely  surgical  patients  it  is  most  convenient 
for  the  nurses  to  cut  the  daily  dressings  necessary  for  each  patient  some  time 
before  the  actual  dressings  are  done.  For  this  purpose  it  is  best  to  have 
several  pieces  of  American  cloth,  made  with  flaps  at  the  edges  (as  in  music 
portfolios),  and  lined  with  some  waterproof  material  (not  macintosh),  such 
as  '  waterproof  muslinette.'  In  these  the  dressings  for  each  case  can  be 
tightly  rolled,  and  tied  with  coloured  tape.  The  dressing  necessary  for  each 
case  can  then  be  laid  by  each  bed,  and  await  without  harm  the  visit  of  the 
surgeon  or  dresser.  In  this  respect  nothing  can  be  worse  than  dressings  cut 
some  hours  beforehand  and  lying  about  unfolded,  or  only  loosely  folded,  ex- 
posed to  the  air  and  to  the  access  of  dust.  If  the  antiseptic  is  vaporisable,  such 
treatment  of  the  gauze  simply  spoils  it,  and  is  the  cause  of  many  failures 
in  the  aseptic  treatment  of  wounds.  If  it  is  fixed,  though  it  may  not  be  so 
prejudicial,  yet  the  free  access  of  dust  will  imperil  the  success  of  the  case. 

Where  the  spray  is  employed,  the  top  of  the  dressing  table  may  be  used 
for  it,  and  for  a  dish  of  antiseptic  lotion  for  instruments  or  for  washing 
wounds.  Many  surgeons  do  not  now  use  the  spray,  but  trust  to  asepticising 
the  wound  after  the  operation  is  over  by  irrigating  it  with  corrosive  sublimate 
solution  or  some  other  antiseptic.  The  writer  has  not  himself  abandoned 
the  spray,  though  he  recognises  that  there  are  disadvantages  attached  to  its 
use.  These,  however,  may  be  minimised  if  their  existence  is  recognised, 
and  they  appear  to  him  to  be  altogether  less  than  the  very  serious  evils  which 
may  arise  from  its  non-use.^ 

'  As  regards  the  use  of  the  carbohc  spray  for  operations,  it  may  be  thought  after  the 
very  explicit  declaration  against  its  utility  by  its  inventor,  Sir  Joseph  Lister,  at  the- 
Berlin  International  Medical  Congress  of  1890,  that  it  would  naturally  fall  into  disuse. 
This  is  no  doubt  largely  the  case,  but  it  is  not  in  accordance  with  the  writer's  own  views 
about  it. 

There  are  two  ways  in  which  the  spray  may  be  used :  (1)  as  a  vapour ;  (2)  as  an 
irrigant.  Sir  J.  Lister  has  always  used  it  in  the  first,  the  wi-iter  in  the  second  way. 
To  obtain  the  first,  the  spray  is  placed  at  a  considerable  distance  from  the  patient — a 
distance  sufficiently  great  to  allow  the  minute  globules  of  carbolic  lotion  to  evaporate  into 
the  air  before  reaching  the  patient,  thus  producing  an  atmosphere  charged  with  carbolic 
acid,  in  which  it  was  beUeved  no  germ  can  live.  To  obtain  the  second,  the  spray  is 
placed  only  a  short  distance  from  the  patient  (2-3  feet),  so  that  the  finely  divided  globules 
of  carbolic  lotion  shall  fall  directly  upon  and  wet  the  wound.  The  use  of  the  spray  in  the 
first  way  is  undoubtedly  a  delusion.  It  sounds  scientific  to  disinfect  the  whole  of  the 
air  about  the  patient  and  the  operator,  but  the  writer  has  convinced  himself  that  it  is  not 
practicable.  Germs  may  remain  untouched  in  this  antiseptic  atmosphere,  and  may  fall 
on  the  wound,  and  produce  the  usual  septic  trouble  afterwards.  In  the  second  way, 
although  germs  may  still  fall  upon  the  wound  untouched  in  the  midst  of  the  spray,  yet 
they  fall  upon  a  surface  wet  with  the  antiseptic,  and  they  are  therefore  quickly  destroyed. 
No  doubt  the  irritating  action  of  carbolic  lotion  is  rather  greater,  when  used  as  an 
irrigant,  than  when  used  in  the  first  way  ;  but  this  disadvantage  is  more  than  overbalanced 
by  the  greater  security  obtained.  It  may  be  said.  Why  then  not  make  use  of  carbolic 
lotion  to  irrigate  the  wound  at  the  end  of  the  operation,  instead  of  using  such  a  cumbrous 


HOSPITAL  HYGIENE  789 

"While  upon  this  part  of  the  subject,  it  is  necessary  to  utter  a  warning 
about  the  neglect  of  antiseptic  precautions,  which  may  very  likely  arise  in 
the  future,  even  if  it  is  not  already  beginning  in  sonie  hospitals.  In  the 
way  surgery  is  now  practised,  medical  students  of  the  present  generation  have 
had  very  few  opportunities  of  seeing  the  results  of  septic  wards  in  our  large 
general  hospitals.  The  cases  do  so  well,  with  such  httle  disturbance  from 
.septic  causes,  that  there  is  great  risk  that  the  surgeons  of  the  future  may  get 
to  disbelieve  in  the  very  serious  risks  which  the  want  of  observance  of  anti- 
septic precautions  will  entail  upon  them.  The  risk  is  the  greater  because 
there  will  be  no  sudden  change  from  surgical  results,  as  they  now  are,  to  the 
Tesults  of  thirty  years  ago.  In  looking  back  over  this  period  it  can  plainly  be 
perceived  that  the  introduction  of  antiseptic  surgery  did  not  work  any  .s?.tcZtZew 
transformation  in  hospital  wards.  For  a  longtime  ih.Q  principles  of  anti- 
septic surgery  were  in  doubt,  and  were  only  practised  by  one  or  two  surgecns 
here  and  there.  An  aseptic  case  or  two  lay  amongst  many  others  mixed  all 
together  in  the  wards.     Nevertheless,  even  those  few  had  a  certain  influence 

method  as  the  spray  ?  There  was  great  weight  in  the  argument  made  use  of,  the  writer 
believes,  by  Sir  J.  Lister,  on  his  first  introduction  of  the  spray,  though  since  then  seldom 
heard,  viz.,  that  during  an  operation,  when  making  successive  incisions,  especially  amongst 
the  muscles,  the  parts  retract  unequally,  and  thus  dust-germs  are  apt  to  get  tucked  away 
into  secure  recesses  of  the  wound,  which  are  never  reached  by  irrigation  performed  after 
the  operation  is  over.  This  risk  is  avoided  if  continuous  irrigation  by  the  spray  is  going 
•on  during  the  whole  performance  of  the  operation. 

Irrigation  in  some  form  is  nearly  always  practised  by  those  who  have  given  up  the 
use  of  the  spray.  But  here  again  there  is  great  difference  of  opinion  as  regards  the  anti- 
septic to  be  used,  and  as  to  the  strength  of  the  solution.  Corrosive  sublimate  solution  is 
that  most  in  use  at  the  present  time,  but  it  is  sometimes  employed  at  a  strength  of  1  to 
1,000,  sometimes  at  1  to  10,000,  and  at  all  degrees  of  strength  between  these  two.  This 
very  great  divergence  in  the  practice  of  surgeons  is  likely  to  engender  carelessness  and 
■disbelief  in  the  minds  of  those  who  are  now  studying  surgery  for  the  first  time.  From 
what  he  has  seen,  the  writer  does  not  believe  in  the  efficacy  of  solutions  of  1  o  10,000. 
While  admitting  that  there  may  be  some  range  of  variation  in  different  cases  in  the 
strength  of  the  solution  we  employ,  the  wi'iter  thinks  that  the  minimum  strength  should 
be  1  to  2,000,  and  that  a  strength  of  1  to  1,000  will  prove  the  right  one  in  the  great  majority 
■of  cases  under  treatment.  For  the  reasons  already  cited,  the  bad  results  of  employing 
too  weak  solutions  will  not  very  obviously  appear  at  once. 

As  an  instance  of  what  harm  may  result  from  the  employment  of  too  weak  solutions, 
the  writer  may  state  what  took  place  some  years  ago  within  his  own  knowledge  at  a  chil- 
dren's hospital  in  the  comparative  infancy  of  asepsis.  For  some  months  there  was 
failure  in  the  aseptic  results  of  operations.  Inquiry  was  made  at  different  times  in  very 
TTarious  directions  to  try  and  account  for  their  failure.  The  goodness  of  the  gauze  was 
suspected ;  the  hygienic  surroundings  of  the  patient,  the  conditions  of  the  operator, 
nurses,  and  house  surgeon  were  inquired  into.  Again  and  again  the  strength  of  the 
antiseptic  solution  was  challenged,  but  the  dispenser  always  sent  in  the  assurance  that  it 
was  right.  This  went  on  for  so  long  that  at  last  the  writer  was  almost  inclined  to  admit 
that  children's  tubercular  joint  operations  (in  which  principally  the  failures  took  place) 
were  more  difficult  to  keep  aseptic  than  the  same  cases  in  the  adult.  Finally,  it  was  dis- 
covered by  the  energy  of  a  new  house  surgeon  (Dr.  Henry  Davy,  now  of  Exeter),  and  this 
only  by  absolutely  standing  over  the  dispenser,  and  watching  him  make  it,  that  by  some 
curious  perversion  of  arithmetical  calculation  he  was  sending  up  the  carbolic  lotion  to 
the  wards,  instead  of  a  strength  of  1  in  20,  something  more  like  1  in  100,  so  that  the 
antiseptic  made  use  of  was  almost  indefinitely  weak.  The  writer  believes  this  was  done 
entirely  ionA  fide,  and  was  due  to  a  failure  of  arithmetical  calculation,  which  once  wrongly 
carried  out  repeated  itself  each  time  in  the  dispenser's  mind.  Another  similar  failure 
in  the  preparation  of  an  antiseptic  solution  of  right  strength  the  writer  detected  in 
another  place  by  having  himself  made  many  times  the  preparation,  and  noticing  the 
difference  in  that  supplied.  This  again  was  due  to  a  wrong  arithmetical  calculation — 
■only  in  this  case  it  was  not  attended  with  such  serious  results. 

It  is  not  within  the  range  of  this  article  to  discuss  the  strength  of  other  antiseptics 
,nor  the  varieties  of  wound  or  operation  in  which  each  different  antiseptic  is  of  most  use. 


790  HYGIENE 

on  the  well-being  of  the  rest,  and,  as  they  increased  in  number,  the  chances 
of  the  rest  of  the  cases,  not  treated  on  antiseptic  principles,  perceptibly  im- 
proved. This  was  because  there  was  a  smaller  proportion  of  foul  air-infecting 
cases  in  the  ward ;  the  surroundings  for  all  the  patients  became  more 
hygienic,  and  consequently  they  did  better.  If  we  imagine  a  ward  of  thirty 
patients,  twenty-nine  of  whom  were  aseptic  cases  and  one  treated  (say  an 
amputation)  without  recourse  to  antiseptics,  it  is  clear  that  this  one  patient 
would  have  a  much  better  chance  of  escaping  septicjiemia  than  if  he  were  one 
in  a  ward  full  of  septic  cases.  Similarly,  at  the  present  time,  a  single  case,  or 
more,  may  be  operated  on  in  our  wards  without  recourse  to  antiseptics,  and  yet 
may  do  well,  because  he  is  surrounded  with  healthy  cases.  Thus  may  arise 
the  risk  of  the  future.  A  young  surgeon,  never  having  seen  the  deplorable 
results  of  surgery  as  older  surgeons  saw  them  thirty  years  ago,  may  operate 
without  the  use  of  antiseptics,  and  may  possibly  be  able  to  point  to  case  after 
case  being  operated  on  successfully,  until  he  begins  himself  to  enunciate  as  a 
law  his  conclusions  that  antiseptics  are  unnecessary,  and  that  surgeons  have 
been  labouring  under  a  great  delusion  in  the  past  as  regards  their  use. 
There  is  very  little  doubt  that  his  results  in  the  process  of  time  will  undeceive 
him,  or  at  any  rate  those  watching  these  results.  But  this  "will  entail  a 
considerable  loss  of  hfe,  and  an  amount  of  suffering  to  individual  patients, 
which  will  only  be  prevented  by  careful  attention  on  the  part  of  medical 
students  and  teachers  to  the  history  of  the  surgery  of  the  past  thirty  or  forty 
years. 

Instrumentation 

Under  this  heading  is  included  the  keeping  of  instruments  used  in 
dressings  and  operations  clean  and  ready  for  use.  The  instruments  got  ready 
for  any  particular  operation  should  be  placed  in  a  shallow  tray  containing  anti- 
septic solution  shortly  before  the  operation  takes  place.  After  the  operation 
they  should  be  at  once  cleansed  from  blood  or  discharges  by  washing  in  cold 
water.  They  may  then  be  sterilised  by  placing  in  boiling  water  for  a  short 
time.  For  steel  instruments  with  a  cutting  edge  this  period  should  at  the 
outside  scarcely  amount  to  two  minutes,  or  the  edge  and  the  polished  surface 
will  be  dulled.  Each  instrument  should  then  be  quickly  dried  and  polished 
before  being  put  away.  If  the  instrument  be  composed  of  metal  and  some 
other  material,  such  as  an  ivory  or  wooden  handle,  only  the  metal  part  (as 
far  as  possible)  should  be  immersed  in  the  boiling  water.  Repeated  immer- 
sions of  wood  or  ivory  in  boiling  water  spoil  them  and  loosen  the  attach- 
ments. Moreover,  it  is  unnecessary ;  the  immersion  of  the  handle  in  the 
antiseptic  fluid  immediately  before  the  operation  sufficiently  asepticises  it, 
and  prevents  the  carrying  of  germs  from  one  patient  to  the  other.  Most 
probably  this  immersion  will  also  asepticise  the  metallic  part,  but  this  is  more 
doubtful.  Most  steel  instruments  have  minute  crevices  and  crannies  (e.g., 
the  serrations  of  artery  forceps  or  minute  depressions  where  spots  of  rust 
have  accidentally  eaten  into  the  metal,  &c.)  ;  these  become  filled  with 
coagula  of  blood  during  the  operation,  and  these  are  exceedingly  difficult  to 
detach  by  the  cleaning  process.  Moreover,  each  of  these  little  masses  of 
coagulum  is  exceedingly  difficult  to  sterilise  by  mere  immersion  in  an  anti- 
septic solution.  The  outside  layer  of  coagulated  albumen  resists  the  action 
of  the  solution,  and,  as  the  mass  adheres  very  strongly  to  the  metal,  germs 
may  remain  unacted  upon  until  accidentally  set  free  by  the  next  operation. 
A  small  metal  (brass  wire)  brush,  used  by  artificers  in  one  of  the  steps  of 
brass  polishing,  is  exceedingly  useful  in  cleaning  out  the  teeth  of  forceps  and 
other  minute  depressions  in  metal  instruments.     But  even  when  all  these 


HOSPITAL  HYGIENE  791 

precautions  have  been  used,  the  writer  has  frequently  seen  most  carefully 
cleaned  instruments,  when  next  put  to  soak  in  water  or  antiseptic  solutions, 
throwing  out  from  some  invisible  crevice  blood-pigment,  which  slightly  stains 
the  water ;  thus  showing  that,  in  spite  of  the  care  used,  some  red  blood-cor- 
puscles were  left  unaltered  on  the  instrument,  and  that  these  have  become 
ruptured  by  endosmosis  from  the  fresh  soaking  in  water,  and  thus  may  very 
possibly  be  centres  of  infection  in  any  fresh  operation.  On  the  other  hand, 
if  the  metal  part  of  the  instrument  be  subjected  for  two  or  three  minutes  to 
the  heat  of  boiling  water,  from  the  conductivity  of  the  metal  for  heat  each 
of  these  little  masses  becomes  of  such  a  temperature  that  it  can  scarcely 
escape  sterilisation.' 

The  only  objection  to  the  heating  process  is  in  the  case  of  knives  used 
for  very  delicate  operations,  where  the  temper  is  a  matter  of  considerable 
importance.  The  degree  of  heat  (212°  F.)  may  have  the  effect  of  altering 
the  temper  to  a  slight  extent,  and  thus  deteriorating  the  edge.  With  large 
knives  and  scalpels,  the  alteration  is  not  of  such  degree  that  it  should  be 
allowed  to  be  of  sufficient  importance  to  warrant  its  non-use  from  this  cause. 
With  a  few  eye-instruments  (cataract  knives,  &c.),  their  small  size,  and  the 
very  perfect  piece  of  metal  of  which  they  are  composed,  make  it  possible 
to  keep  the  whole  of  the  surface  at  such  an  exceedingly  high  degree  of  polish 
that  the  precaution  may  not  be  so  necessary  in  their  case.  But  in  all  other 
cases  the  precaution  is  an  essential  one.  In  the  majority  of  surgical  instru- 
ments it  must  be  manifest  that  there  cannot  be  the  slightest  objection  to 
their  sterilisation  by  heat.  Directors,  probes,  retractors,  all  kinds  of  bone 
forceps,  small  saws,  trephines,  elevators,  and  a  vast  number  of  other  instru- 
ments can  all  be  most  easily  sterilised  by  its  use.  It  is  especially  essential 
in  those  which  are  actually  used  upon  the  flesh  of  the  patient.  I  need  only 
instance  artery  forceps,  the  serrated  teeth  of  which  need  the  greatest  care. 
Again,  tracheotomy  tubes  are  instruments  to  which  the  heat-sterilising  pro- 
cess can  be  most  advantageously  applied.  And  there  is  no  class  of  instrument 
in  which  the  absence  of  this  precaution  is  attended  with  more  dire  results. 
In  years  gone  by,  when  the  disinfection  of  instruments  was  less  thought 
about  than  at  the  present  time,  and  when  less  was  known  about  the  causa- 
tion of  disease,  the  writer  has  seen  numerous  cases  of  tracheotomy  followed 
by  fatal  results  from  diphtheritic  infection  of  the  wound,  arising  from  the 
metal  tracheal  tube  not  having  been  perfectly  sterilised  after  having  been 
previously  used  in  an  infectious  case.  Thus  a  tracheotomy  might  be  done  for 
a  case  of  scalded  glottis  ;  the  child  would  do  well  for  a  day  or  two,  then 
develop  a  diphtheritic  exudation  about  the  wound,  which  would  rapidly  spread 
to  the  scalded  glottis  and  the  trachea,  and  the  child  would  die  from  this  cause. 

Though  diphtheritic  tracheotomy  wounds  cannot  even  now  be  wholly  pre- 
vented (a  case  arising  every  now  and  then,  when  the  operation  has  been  per- 
formed for  diphtheria  of  the  larynx,  either  by  auto-infection  or  by  extension 
of  the  diphtheritic  inflammation  from  the  throat  downwards),  yet  it  is  probable 
that  the  much  greater  success  which  attends  tracheotomy  now  than  when 
the  operation  was  first  introduced  is  due  for  one  reason  to  the  much  greater 

>  A  word  must  be  said  here  in  favour  of  the  surgeons  of  the  future  learning  something 
of  artisan  knowledge  respecting  the  manipulation  of  their  instruments,  and  the  materials 
of  which  they  are  composed.  It  will  be  found  very  useful.  Many  surgeons  are  no  doubt 
accomplished  mechanicians,  but  amongst  many  others  there  is  a  tendency  to  look  with 
contempt  during  their  earlier  years  in  the  profession  (when  alone  they  have  time  to  acquire 
the  knowledge)  upon  any  knowledge  of  this  kind.  This  is  a  mistake.  As  far  as  the  anti- 
septic treatment  of  instruments  is  concerned,  they  may  be  kept  much  more  perfectly 
aseptic  if  the  surgeon  is  willing  to  look  after  them  himself,  and  has  the  requisite  amount 
of  knowledge  as  regards  the  treatment  of  the  material  of  which  they  are  composed. 


792  HYGIENE 

care  which  is  taken  in  the  disinfection  of  the  tubes  than  formerly.  In  the 
instruments  used  on  the  aUmentary  or  genito-minary  mucous  membrane 
the  dismfection  of  the  instruments  is  of  very  great  importance  on  account  of 
the  frequent  infective  character  of  the  discharges.  As  far  as  these  instru- 
ments consist  of  metal,  no  difficulty  will  be  met  with  in  purifying  them  ;  but 
in  the  case  of  gum-elastic  instruments,  whether  they  be  throat  bougies,  rectal 
tubes,  or  catheters,  there  is  considerable  difficulty  in  knowing  what  to  do. 
They  cannot  be  sterilised  by  heat  without  injury.  Although  it  is  a  common 
practice  to  dip  a  gum-elastic  catheter  into  hot  water  to  soften  it  and  render 
it  more  flexible,  yet  mere  hot  water  is  not  sufficient  for  sterihsation.  Nothing 
less  than  a  boiling  temperature  continued  for  a  minute  or  two  will  be  suf- 
ficient for  the  destruction  of  germs,  and  it  will  be  found  that  to  boil  gam- 
elastic  instruments  for  this  time  is  equivalent  to  their  very  rapid  destruction. 
Many  antiseptics  soften  and  destroy  the  gum  resin  which  gives  the 
smoothness  and  polish  to  the  outer  surface  of  these  instruments.  The  writer 
is  convinced  that  the  common  fashion  of  wrapping  a  gum-elastic  catheter  in 
a  piece  of  carbolic  gauze  is  very  prejudicial  to  the  catheter,  rendering  it 
sticky  and  causing  the  loss  of  its  polish,  besides  being  of  doubtful  utility  as 
an  antiseptic.  Probably  the  better  course  is  to  dip  the  catheter  in  a  watery 
solution  of  corrosive  sublimate  (1  in  1,000)  for  a  minute  or  two  before  use.  But 
for  all  hollow  gum-elastic  instruments  it  is  best  to  burn  them  directly  there 
is  the  least  suspicion  of  their  integrity.  The  inner  bore  of  all  such  instru- 
ments is  exceedingly  difficult  to  purify  satisfactorily,  after  they  have  been  used 
for  cases  in  which  blood  or  pus  gains  access  to  the  interior.  And  although 
this  sm'face  does  not  come  into  absolute  contact  with  the  mucous  membrane 
of  the  patient,  yet  it  may  easily  be  a  source  of  infection,  if  there  be  any 
impure  material  adhering  to  it.  Even  with  a  silver  catheter,  it  must  be  a 
matter  of  every-day  experience  to  surgeons  how  difficult  it  is  to  clear  away 
the  last  traces  of  blood-clot  from  its  interior.  Though  it  may  have  been 
soaked  in  water,  and  blown  through,  and  raked  out  with  the  stilette,  though 
even  a  current  of  water  may  have  been  run  through  it,  the  surgeon  will  not 
infrequently  find,  after  drying  and  polishing,  that  when  again  put  into  fresh 
water  before  use  a  slight  colouration  issues  from  its  interior.  These  catheters, 
however,  can  be  easily  sterilised  by  heat,  and  it  is  a  considerable  argument  for 
their  use  in  skilled  hands.  If,  however,  there  are  such  difficulties  in  rendering 
the  inner  bore  of  metallic  catheters  clean  without  the  aid  of  heat,  much 
more  will  there  be  with  gum-elastic  instruments.  The  inner  surface  is  rough 
and  h-regular,  and  has  none  of  the  beautiful  polish  of  the  exterior,  as  will  be 
seen  by  cutting  such  a  catheter  open.  In  private  practice  the  writer  always 
tries  to  make  use  of  new  catheters  for  every  fresh  patient,  or  to  keep  the 
same  catheters  for  the  same  patient.  Even  this  is  difficult,  and  in  hos- 
pital practice  it  will  be  found  next  to  impossible.  Some  plan,  then,  by 
which  the  catheter  can  be  purified,  or,  if  not  absolutely  purified,  rendered 
innocuous  to  the  patient  next  succeeding,  is  very  important  to  obtain.  Such 
plan  the  writer  has  carried  out  lately  by  dipping  the  catheter  into  a  thin 
solution  of  spirit  polish,  rendered  flexible  and  unlikely  to  crack  by  the  addition 
of  a  small  quantity  of  castor  oil  (10  drops  to  a  fluid  ounce  of  the  polish). 
After  such  dipping,  the  catheter  has  to  be  drained  and  hung  up  to  dry,  all 
touching  being  avoided  until  it  is  absolutely  dry.  This  process  renews  the 
polish  on  the  exterior,  and  if  there  be  any  foreign  material  in  the  interior, 
it  varnishes  it  down,  so  that  it  no  longer  floats  about  freely  when  the  catheter 
is  used — to  say  nothing  of  the  antiseptic  effect  of  the  rectified  spirit  upon 
it  during  the  soaking  and  drying  processes.  Of  course,  this  process  sooner 
or  later  chokes  up  the  bore  and  eye  of  any  catheter,  the  smaller  ones  espe- 


HOSPITAL  HYGIENE  793 

-cially,  but  it  will  be  found  that  it  prolongs  the  life  of  a  catheter  very  much, 
and  it  also  offers  a  mode  of  proceeding  by  which  one  is  not  afraid  to  make 
use  of  a  catheter  about  which  it  is  doubtful  whether  it  has  been  used  before 
■or  not.  It  will  be  of  especial  service  to  country  practitioners,  whose 
opportunities  of  getting  new  catheters  are  very  limited,  and  who  yet  do 
not  wish  to  keep  a  large  stock  of  such  perishable  articles. 

Sponge  Pkepabation  and  Cleansing 

The  question  whether  sponges  are  reliable  articles,  and  should  be  used  for 
■operations,  has  for  many  years  been  a  moot  point  amongst  those  practising 
antiseptic  surgery.  By  many,  sponges  have  been  discarded  altogether,  as 
involving  too  much  risk  of  carrying  material  from  one  patient  to  another. 
These  surgeons  use  lint  or  wads  of  cotton-wool,  which  are  thrown  away  after 
the  operation.  Since  the  manufacture  of  the  cheap  cotton-wool  artificial 
sponges  (each  containing  a  glass  globule  with  eucalyptol  in  its  interior,  which 
is  to  be  crushed  at  the  time  of  use),  the  performance  of  even  large  operations 
has  become  very  possible  by  their  use.  And  it  may  be  laid  down  as  a  general 
rule  that  these  artificial  sponges  should  be  used  in  all  foul  cases,  if  possible. 
But  even  these  are  very  imperfect  substitutes,  and,  in  fact,  true  sponges  are 
.articles  which  will  not  be  lightly  given  up  by  those  who  know  their  valuable 
■qualities  if  in  any  way  they  can  be  made  reliable.  Other  surgeons  will  only 
use  new  sponges ;  this,  however,  is  a  very  expensive  proceeding,  almost  im- 
possible for  hospital  practice,  and  it  distinctly  introduces  a  new  risk — in  the 
imperfect  freeing  of  the  new  sponge  from  all  the  sand  and  other  foreign  material 
which  commercial  sponges  contain.  It  is  possible  to  do  this  effectually  where 
■  only  a  small  number  of  new  sponges  have  to  be  prepared,  but  it  would  be 
practically  impossible  where  a  very  large  number  are  used,  as  would  be  the 
case  if  new  sponges  had  to  be  prepared  for  every  operation.  As  a  matter  of 
fact,  the  writer  believes  from  long  experience  that  sponges  may  be  so  prepared 
:and  cleansed  after  each  operation  that  they  can  be  used  with  perfect  safety 
from  one  patient  to  another.  The  first  cleansing  of  a  commercial  sponge 
from  sand,  &c.,  consists  in  first  shaking  and  beating  the  sand  out  dry,  then 
;  soaking  and  squeezing  in  many  successive  waters.  This  will  probably  take 
days  or  weeks  to  perform.  It  is  very  desirable  that  it  should  be  thoroughly 
done,  for,  in  addition  to  the  sand,  new  sponges  generally  contain  very  minute 
transparent  spines,  which  run  into  the  skin  and  are  very  painful  and  difficult 
to  remove,  as  all  who  have  cleaned  new  sponges  will  know  to  their  cost. 
The  irritant  effect  of  these  spines  upon  a  wound  may  be  well  imagined  by 
those  who  have  experienced  their  effect  on  the  skin.^  When  free  from  the 
sand,  a  new  sponge  may  be  softened  and  bleached  by  first  soaking  in  fairly 
strong  solution  of  permanganate  of  potassium  until  the  sponge  assumes  a  deep 
brown  tint,  and  then  passing  it  quickly  through  a  solution  of  sulphurous  acid 
'(the  pharmacopoeial  preparation  mixed  with  an  equal  bulk  of  water).  This 
process  not  only  whitens  and  softens,  but  detaches  and  dissolves  hard  particles 
remaining,  and  after  again  washing  freely  in  water  the  sponge  is  ready  for  use. 

Another  plan,  recommended  by  Borham,  and  adopted  by  Greig  Smith 
(*  Abdominal  Surgery,'  4th  edit.,  p.  64),  consists  in  soaking  the  sponge,  after 
treatment  with  the  potassium  permanganate,  in  a  solution  of  sodium  hypo- 

'  The  freeing  of  imported  sponges  from  sand,  &c.,  is  now  generally  done  by  machinery 
on  a  very  large  scale.  The  purchase  of  the  already  cleaned  sponges  saves  much  time  and 
labour,  but  even  in  these  some  sand  is  left  behind,  and  care  should  be  taken  to  free  them 
from  this  remnant  as  carefully  as  possible.  Bleached  sponges  can  now  also  be  purchased, 
lof  course  at  considerably  enhanced  cost. 


794  HYGIENE 

sulphite  (half  a  pound  to  a  gallon  of  water).  To  this  solution,  after  soaking^ 
the  sponge  for  a  time,  about  four  ounces  of  oxalic  acid  are  added.  A  chemical 
action  follows,  sodium  oxalate,  sulphurous  acid,  and  free  sulphur  resulting. 
The  sponge  becomes  rapidly  bleached,  and  any  free  fibrin  contained  in  its 
meshes  is  dissolved  out.  The  sulphur  set  free  requires  a  good  deal  of  wash- 
ing to  get  rid  of  it,  and  hence  this  process  takes  longer  than  that  already 
advised.  On  the  other  hand,  a  small  quantity  of  free  sulphur  left  imbedded 
in  the  sponge  probably  slowly  oxidises,  and  thus  may  tend  to  keep  it  sweet. 
When  a  sponge  has  been  saturated  iritli  blood  during  an  operation  it 
should  first  be  cleaned  by  soaking  and  squeezing  in  frequently  renewed  cold 
water.  (Very  hot  water  coagulates  the  albumen  of  the  blood  and  makes  the 
sponge  much  more  difficult  to  clean.  It  also  damages  the  texture  of  a  sponge, 
and  boiling  a  sponge  so  shrinks  and  contracts  it  that  it  is  scarcely  fit  for  use 
afterwards.  Hence  the  method  of  heat  is  inapplicable  in  the  disinfecting  of  a 
sponge.)  When  free  from  blood  and  coagulum,  as  far  as  possible,  it  should  be 
put  to  soak  in  carbolic  lotion  (1  in  40)  for  twelve  to  twenty  hours  ;  then  again 
washed  freely  in  cold  water  before  being  put  aside  for  use.  Every  sponge 
before  a  fresh  operation  is  put  to  soak  in  1  in  40  carbolic  lotion.  This  method 
is  the  one  almost  universally  in  use  at  Guy's  Hospital,  and  gives  satisfactory 
results.  If  a  sponge  has  been  used  for  a  very  foatid  discharge,  it  should  be 
either  thrown  away  or  put  to  soak  in  some  of  the  bleaching  solution  of  sul- 
phurous acid  for  a  quarter  of  an  hour  before  soaking  in  the  carbolic  hquid. 
It  is  curious  that  sulphurous  acid  has  very  httle  bleaching  power  upon  a 
sponge  which  has  once  been  soaked  in  carbolic  solution,  though  it  readily 
bleaches  before  this  is  done.  The  writer  has  thus  gone  into  the  question  of 
sponge  treatment  because  he  believes  it  to  be  one  of  very  considerable  im- 
portance. For  a  long  time  he  was  doubtful  whether  any  cleansing  process 
was  sufficient  for  a  sponge  once  saturated  with  blood,  but  long  experience 
and  careful  watching  of  the  cases  where  sponges  so  treated  have  been  used 
have  convinced  him  that,  if  fairly  done,  they  can  be  relied  on.  The  results 
of  abdominal  surgery  with  such  sponges  have  perhaps  done  more  to  convince 
him  of  the  efficiency  of  the  process  than  anything.  He  has  used  many  other 
methods  also.  A  dilute  solution  of  a  caustic  alkali  has  perhaps  been  the 
favourite  ;  it  tends  to  dissolve  the  fibrinous  coagulum,  but  it  also  damages 
the  texture  of  the  sponge  if  frequently  used  ;  and  he  has  come  to  the  con- 
clusion that  it  is  not  necessary. 


Cooking  Arrangements 

The  ward  kitchen  should  always  be  separated  from  the  ward,  and' 
separate  ventilation  should  be  provided  for  it.  The  old  custom  of  cooking 
in  the  ward  by  nurses  or  helpers  can  only  be  described  by  the  word  '  nasty.' 
It  is  probably  not  so  injurious  as  many  other  things  about  a  ward,  but  the 
mingling  of  the  fumes  of  the  cooking  with  the  air  of  the  ward  destroys  its 
freshness  and  cannot  conduce  to  the  patients'  appetites.  Moreover,  it  takes 
off  the  attention  of  the  nurses  from  their  proper  duty,  viz.,  nursing. 


Isolation  Wards 

These  are  absolute  necessities,  both  for  medical  and  surgical  cases, 
in  all  hospitals  :  in  the  latter  more  especially,  for  erysipelas  and  very  foul 
cases  ;  in  the  former,  when  there  is  an  epidemic  outbreak  of  zymotic  disease,, 
such  as  scarlatina,  measles,  small-pox,  typhus,  &c. 


HOSPITAL  HYGIENE  795 

The  avoidance  of  the  undue  herding  together  of  the  fever  cases  causes 
the  dilution  of  the  poison  and  contributes  in  a  marked  degree  to  their  re- 
covery. It  is  always  difficult  to  prove  this  from  statistics,  the  number  of 
cases  dealt  with  even  in  the  large  wards  at  Guy's  Hospital  being  but  small. 
But  it  is  supported  by  much  that  is  observed  in  private  practice  in  infectious 
cases,  and  also  by  what  has  been  observed  in  some  of  the  fever  hospitals.  In 
the  latter,  the  late  Dr.  Mahomed  (who  as  physician  to  the  Fever  Hospital  at 
Islington  had  a  large  amount  of  experience  in  such  cases)  is  the  writer's 
authority  for  saying  that  after  every  time  of  purifying,  white-liming,  and 
re-painting  the  wards,  the  patients  with  scarlatina  first  received  into  them 
did  better  than  those  received  into  wards  not  so  purified ;  that  the  walls,  &c. 
after  a  time  became  so  saturated  with  the  poisonous  emanations  that  even 
fresh  scarlatinal  cases,  presenting  a  mild  type  when  first  received,  were 
very  liable  to  severe  throat  troubles,  glandular  abscesses,  and  sloughings, 
&c.,  when  they  were  received  into  wards  at  all  stale.  And  this  is  in  accord- 
ance with  the  writer's  own  experience  in  private  practice.  He  has  on  two 
or  three  occasions  seen  an  epidemic  of  scarlatina  run  through  a  large  family 
or  school  of  children.  These  children  have  been  placed  in  two  or  three  rooms 
in  the  top  of  the  house,  case  after  case  as  they  occurred.  The  first  case  has 
been  of  a  mild  type  and  has  done  well.  The  succeeding  cases  have  presented 
symptoms  of  increasing  intensity,  and  in  the  last  case  or  two  he  has  been 
called  in  to  do  various  surgical  operations  on  their  throats  for  sloughing 
glands,  and  phagedenic  ulcerations  of  the  worst  possible  type.  He  has  always 
attributed  this  to  the  intensification  of  the  poison  in  the  rooms  set  apart 
for  the  patients.^ 

In  the  case  gf  scarlatina,  measles,  and  small-pox  it  may  be  conceded  that 
isolation  rooms  or  wards  are  absolutely  necessary  for  the  safety  of  the  rest 
of  the  patients,  but  great  care  should  be  taken  in  the  frequent  purification 
and  disinfection  of  such  wards.  In  the  case  of  typhus  probably  the  same 
is  true,  though,  with  due  care  as  regards  number,  cases  of  typhus  in  former 
epidemics  have  been  placed  and  treated  successfully,  without  spread  of  the 
malady,  in  the  large  wards  at  Guy's  amongst  the  other  patients.  In  the 
case  of  typhoid  and  diphtheria  a  certain  number  of  such  cases  are  still 
admitted  into  the  general  medical  wards  with  favourable  results.  As  regards 
typhoid,  the  spread  of  the  malady  amongst  surrounding  patients  is  almost 
unknown,  if  the  before-named  proportion  of  cases  is  duly  maintained.  It 
is  very  many  years  since  an  epidemic  of  typhoid  has  occurred  in  a  Guy's 
ward — and  when  that  took  place  it  was  due  to  accidental  overcrowding  of 
typhoid  cases  into  one  ward.  As  regards  diphtheria,  the  risk  of  the  spread 
of  the  disease  is  greater,  but  more  amongst  those  nursing  the  case  than 
amongst  the  ordinary  patients,  though  even  the  latter  is  not  unknown. 

Although  an  isolation  ward  should  be  attached  to  every  general  hospital, 
it  is  not  desirable  that  this  ward  should  be  made  use  of  for  the  treatment  of 

'  The  writer  would  note  here  the  very  great  improvement  in  the  treatment  of  such 
cases  by  the  extended  use  of  aerial  disinfectants.  The  old  method  of  a  sheet  saturated 
with  carbolic  solution  and  suspended  in  the  chamber  had  a  certain  value,  no  doubt,  but  it 
was  altogether  insufficient.  In  the  method  of  vapourising  carbolic  or  creosotic  antiseptic 
compounds  by  heat,  there  is  a  very  great  improvement.  Many  instruments  for  this  pur- 
pose are  now  sold.  The  little  cresolene  lamp  may  be  cited  as  an  instance.  This  is  a  very 
small  petroleum  lamp  with  a  porcelain  cup  fixed  over  it,  in  which  the  cresolene  is 
placed.  The  cresolene  only  evaporates  very  slowly,  and  condenses  on  everything  in  the 
chamber,  so  that  in  a  room  in  which  it  has  been  burning  for  some  hours  everything — 
curtains,  walls,  bed,  &e. — smells  more  or  less  of  the  material.  Efficient  antiseptics  used 
in  this  way  cannot  but  have  a  considerable  value  in  diminishing  the  virulence  of  the  septic 
poison. 


796  HYGIENE 

an  infectious  fever  during  its  entire  course,  but  only  for  the  separation  of 
the  case  from  other  patients  while  the  diagnosis  remains  doubtful.  When 
the  case  has  folly  declared  itself,  it  should  be  removed,  if  possible,  to  a 
hospital  for  such  cases  entirely  separated  from  general  cases.  In  London  this 
is  carried  out  by  the  removal  of  such  cases  to  the  hospitals  of  the  Metropolitan 
Asylums  Board. 

The  disinfection  of  cm  isolation  ward  is  best  accomplished  by  burning 
sulphur  in  it,  and  keeping  the  room  as  tightly  closed  as  possible  for  twenty- 
four  hours  afterwards.  The  fireplace  should  be  closed  by  temporarily 
pasting  paper  over  it,  and  the  crevices  of  the  windows  and  doors  as  far  as 
possible  by  sand-bags.  The  amount  of  sulphur  burnt  should  vary  with  the 
infectiousness  of  the  case  or  cases  which  have  been  previously  in  it.  A 
good  rule  is  to  burn  not  less  than  one  pound  to  every  2,000  cubic  feet  of 
space.  The  sulphurous  acid  gas  so  produced  impregnates  everything  in  the 
apartment,  and  acts  in  itself  as  a  most  potent  germ-destroyer.  In  addition 
it  oxidises  slowly  in  contact  with  the  atmosphere,  and  thus  becomes  con- 
verted into  sulphuric  acid,  which  remains  very  persistently  about  every- 
thing, and  this  acts  still  further  as  a  germicide.  At  the  end  of  twenty-four 
hours  the  Avard  should  be  thoroughly  aired,  and  walls  and  floor  washed  with 
solution  of  carbolic  acid  (about  1  to  40).  Fresh  white-liming  the  ceiling 
is  a  good  adjunct,  but  it  cannot  be  done  after  every  case,  and  it  is  not 
necessary.  At  the  London  Fever  Hospital  the  small  separate  rooms  used 
for  private  patients  and  doubtful  cases  are  disinfected  after  every  patient, 
but  the  larger  wards  can  only  be  done  periodically.  The  reason,  however, 
for  disinfection  of  the  small  rooms  after  every  patient  is  that,  when  patients 
are  first  taken  in,  the  diagnosis  is  sometimes  doubtful,  and  it  would  not  be  right 
to  place  a  patient,  perhaps  not  suffering  fi-om  any  infectious  disease  at  all,  in 
a  ward  which  had  been  just  occupied,  say,  by  a  scarlatina  or  measles  case, 
without  in  the  first  place  thoroughly  disinfecting  it.  The  same  rule  should 
be  applied  to  all  isolation  wards  in  general  hospitals.  It  has  long  been  in 
use  in  those  at  Guy's  Hospital  with  the  most  beneficial  results. 

Kesults. 

With  the  greatly  increased  care  given  to  the  hygienic  condition  of  the 
wards  in  our  hospitals  a  most  remarkable  improvement  has  followed  in  the 
mortahty  statistics  of  operations.  Erysipelas  and  pyaemia  have  almost 
completely  disappeared  as  endemic  affections  in  our  hospitals.  Indeed,  if 
a  case  of  blood  poisoning  is  seen  in  a  ward,  it  may  be  almost  certainly 
assumed  that  it  has  either  been  admitted  as  such  from  outside  the  hospital, 
or  that  the  case  has  been  of  such  a  nature  as  to  lead  to  very  widespread  in- 
fection of  poisonous  material,  such  as  cannot  be  entirely  disinfected  and  de- 
stroyed. As  instance  of  the  former,  the  writer  may  mention  the  cases  of 
acute  necrosis — examples  of  which  are  always  to  be  found  in  surgical  wards. 
As  instance  of  the  latter,  the  cases  in  which  London  mud  and  dirt  have  been 
very  deeply  ingrained  into  the  cutaneous  and  deeper  structures,  in  those 
accidents  in  which  patients  have  been  dragged  for  a  distance  along  the  pave- 
ment or  over  granite  setts,  thereby  producing  a  very  deep  inoculation  of  the 
foulest  dirt  in  existence,  viz.,  the  various  excreta  which  constitute  the  mud 
and  dust  of  the  streets  of  our  large  towns.  Such  inoculations  often  occur 
over  areas  of  tissue  so  extensive,  that  it  is  practically  impossible  to  remove 
or  completely  destroy  the  infective  material.  The  difficulty  is  rendered  the 
greater,  because,  in  spite  of  the  foulness  of  the  material  ingrained  into  the 
tissues,  many  of  these  cases  show  such  power  of  resistance  to  the  poison 


HOSPITAL  HYGIENE  797 

that  they  ultimately  do  well.  Nevertheless,  in  such  cases  the  risk  of  septi- 
caemia and  tetanus  is  considerable.  Thus  in  a  case  which  was  admitted  into 
the  writer's  ward  at  Guy's  Hospital,  while  away  for  his  summer  holiday 
some  years  ago,  the  patient  had  fallen  into  a  dustbin,  producing  a  compound 
fracture  of  both  his  legs.  The  bones  protruded  and  were  caked  with  dust. 
They  were  very  carefully  cleaned  and  disinfected  before  reduction,  but  it  was 
recognised  at  the  time  that  perfect  cleansing  and  disinfection  were  impos- 
sible. On  his  return  the  writer  found  the  boy  suffering  both  from  tetanus  and 
from  marked  signs  of  pytcmia.  He  amputated  the  worse  leg,  but  naturally 
failed  to  save  the  life  of  the  patient.  The  post-mortem  examination  showed 
abscesses  in  the  lungs  and  commencing  suppurations  in  the  joints.  In- 
stances such  as  this  might  be  multiplied,  but  it  is  evident  that  their  existence 
does  not  prove  anything  against  the  healthiness  of  surgical  wards.  It  is  only 
when  cases  of  blood  poisoning  arise  de  novo  within  the  ward,  in  cases  of 
operation  in  which  the  wound  was  originally  sweet,  and  ought  to  have  been 
kept  so,  that  any  fear  should  arise  as  regards  the  hygienic  surroundings. 

There  can  be  no  doubt  that  the  main  cause  of  the  improved  results  in  all 
surgical  wards  of  late  years  is  almost  entirely  due  to  the  adoption  of  the  plan 
of  treating  wounds  advocated  by  Sir  Joseph  Lister.  In  Guy's  Hospital,  for 
example,  the  condition  of  the  surgical  wards,  as  regards  ventilation,  heating, 
and  general  sanitation,  has  not  been  very  materially  altered  from  what  it  was 
twenty  years  ago.  And  yet  by  the  simple  adoption  of  this  mode  of  treatment 
of  wounds,  erysipelas,  pyaemia,  and  blood  poisoning,  as  just  said,  have  been 
almost  abolished  from  the  wards,  and  operations  of  the  most  serious  kind 
are  now  done  safely,  which  formerly  would  almost  certainly  have  terminated 
fatally.  This  improved  state  of  the  wards  reacts  also  in  the  improved 
health  of  the  resident  medical  staff.  Twenty  years  ago  it  was  exceedingly 
rare  for  the  house  surgeon  of  the  period  to  pass  through  his  four-months 
term  of  office  without  being  laid  up  once  or  more,  often  by  an  attack  of  what 
was  called  *  surgical  sore  throat ' — a  form  of  septic  absorption  due  to  foul 
smeUs  arising  from  surgical  wounds  and  dressings.  Now  the  occurrence  of 
surgical  sore  throat  in  the  resident  staff  is  very  rare.  Again,  the  writer  will 
have  to  show  later  on  that  in  quite  another  department  of  medicine,  viz.,  mid- 
wifery, the  great  improvement  in  the  mortality  of  the  General  Lying-in  Hos- 
pital took  place — not  after  structural  alterations,  and  improved  hygienic  apph- 
ances  about  the  hospital — but  after  the  use  of  corrosive  sublimate  solution  as  a 
germicide,  for  injections,  for  the  nurses'  hands,  and  for  disinfecting  all  instru- 
ments. The  writer  would  not  wish  for  one  instant  to  undervalue  the  importance 
of  all  hygienic  arrangements  in  hospital  and  ward  construction,  &c.,  as  well  as 
the  hygienic  ordering  of  a  ward ;  but  it  is  important  that  the  relative  value  of 
these  factors  should  not  be  lost  sight  of,  and  the  fact  remains  that  to  the 
recognition  of  the  truth  of  these  principles  must  be  attributed  the  great 
surgical  triumphs  of  the  age. 

As  an  example  of  the  condition  of  things  in  surgical  wards  prior  to  the 
advent  of  Listerism  (a  condition  which  sounds  almost  incredible  now,  after 
the  lapse  of  only  twenty  years),  the  writer  may  mention  an  incident  which 
occurred  to  him  when  first  appointed  (in  1870)  on  the  surgical  staff  of  Guy's 
Hospital.  One  of  his  early  operations  was  an  amputation  through  the  thigh 
for  a  compound  smash  of  the  leg.  The  Sister  of  the  ward  (who  had  been 
forty  years  in  the  service  of  the  hospital)  shook  her  head  after  the  operation 
and  prophesied  the  death  of  the  patient,  remarking  that  '  these  cases  never- 
recovered.'  In  that  case  she  proved  right,  though  the  statement  itself  was 
no  doubt  an  exaggeration.  Still  it  shows  the  general  impression  which  the 
results  of  these  thigh  amputations  had  left  in  her  mind.     At  the  present 


798  HYGIENE 

time  no  Sister  of  any  experience  in  Guy's  Hospital  could  repeat  such  a  state- 
ment. Indeed,  thigh  amputations  in  the  lower  thigh  for  disease  (excluding 
such  cases  as  senile  gangrene,  &c.)  have  come  to  he  regarded  as  among  the 
safest  of  major  operations,  and  this  is  due  mainly  to  the  abolition  of  pyremia 
and  septiciEmia  in  the  wards,  from  attention  to  all  these  various  hygienic 
•details. 

The  statistics  of  amputation  of  the  thigh  as  given  in  one  of  the  older 
surgery  books  offer  striking  testimony  to  the  difference  in  the  condition  of 
hospitals  now  as  compared  with  thirty  years  ago.     Thus,  in  Mr.  Erichsen's 

*  Surgery  '  (4th  edition,  1804),  p.  31,  a  table  is  given  of  amputations  of  the 
thigh  for  injury  by  various  operations,  in  which  the  mortality  is,  for 
primary  amputations,  about  74  per  cent. ;  for  secondary  amputations, 
about  61  per  cent.  In  Mr.  Dent's  recent  paper  on  the  mortality  in  400 
<;ases  of  amputations  at  St.  George's  Hospital,  performed  since  1874   {vide 

*  Med.-Chir.  Trans.'  for  18U0,  vol.  Ixxiii.)  a  table  is  given  (p.  8G9)  of  thirty- 
five  cases  of  primary  and  secondary  amputations  for  injury,  with  a  mortality 
of  62  per  cent.  At  first  sight  this  does  not  seem  any  very  marked  improve- 
ment on  the  preceding,  but  when  it  is  known  that  this  table  includes  double 
amjmtations,  which  were  all  fatal,  and  that  part  of  the  period  referred  to 
includes  cases  in  which  antiseptic  surgery  was  either  not  practised  at  all 
■or  only  very  imperfectly  attended  to,  it  will  be  seen  that  the  mortality  repre- 
sents a  very  considerable  improvement  on  what  has  gone  before.  The 
same  relative  improvement  may  be  noticed  by  comparing  the  amputations 
through  the  thigh  (performed  for  disease)  in  the  same  hospital  at  different 
periods.  At  this  hospital  careful  statistics  of  the  results  of  all  the  amputa- 
tions have  been  kept  since  1852.  This  period  may  be  divided  into  two  ^ 
(corresponding  with  the  dates  of  Mr.  Holmes'  and  Mr.  Dent's  papers  respec- 
tively on  the  subject).  The  first  period  is  from  1852  to  1874 ;  the  second  from 
1874  to  1888.  During  the  first  period,  antiseptic  surgery  was  mostly  not 
practised  at  all,  though  towards  the  end  of  the  time  very  imperfect  attempts 
at  its  introduction  were  made.  During  the  second  period,  the  principles  of  anti- 
septic surgery  were  much  more  fully  understood  and  practised,  though  even 
this  includes  some  cases  in  the  earlier  years  not  so  treated.  In  the  first 
period,  the  mortality  of  amputation  of  the  thigh  (for  disease)  amounts  to 
about  29  per  cent. ;  in  the  last  period,  to  16'9  per  cent.  The  same 
thing  is  to  be  observed  in  the  amputations  of  the  leg  for  disease.  In 
the  earlier  period  110  amputations  gave  a  mortality  percentage  of  24*5  ;  in 
the  latter  period,  in  fifty-eight  amputations,  of  10'3.  Again,  in  the  amputa- 
tion of  the  arm  for  accident,  a  mortality  of  about  88  per  cent. ;  in  the 
latter  one,  of  20  per  cent.  In  the  same  amputation  for  disease,  a  mor- 
tahty  in  the  first  period  of  about  14  per  cent.,  against  a  mortahty  of  0 
per  cent,  in  the  second  (10  amputations).  Similar  examples  (obtained  by 
comparing  the  results  given  in  the  same  papers)  might  be  multiplied.  The 
writer  may,  however,  be  permitted  to  cite  the  results  {loc.  cit.,  page  363),  in 
which  Mr.  Dent  compares  all  the  amputations  included  together,  but  divided 
into  those  performed  at  different  ages.  After  gi\'ing  a  table  (to  which  the 
Avriter  would  refer  those  interested  in  the  subject),  he  says  : — '  The  most 
noticeable  contrast  will  be  observed  in  the  third  series  of  amputations, 
between  the  ages  of  twenty  and  fifty.  The  mortality  between  the  ages  of 
twenty  and  thirty,  which  in  the  first  series  amounted  to  18"9  per  cent.,  and 
in  the  second  series  to  34-7  per  cent.,  in  the  third  has  fallen  to  14"7  per  cent. 

'  In  the  paper  referred  to,  Mr.  Dent  divides  the  periods  into  tJiree,  but  for  my 
purpose  this  needlessly  complicates  and  leuf^thens  the  subject. 


HOSPITAL  HYGIENE  799 

Between  the  ages  of  thirty  and  forty,  the  jfigures  are  still  more  striking,  for 
the  mortality  as  shown  in  Table  I.,  which  in  the  first  series  was  39-6  per 
cent.,  and  in  the  second  40-4  per  cent.,  has  in  the  third  series  fallen  to  14-2 
per  cent.  Between  the  ages  of  forty  and  fifty,  much  the  same  results  will 
he  observed.  The  improvement  shown  in  the  third  series  is  chiefly  due 
to  the  diminished  mortality  in  these  three  divisions.' 

Still  more  striking  becomes  the  individual  experience  of  a  surgeon 
practising  antiseptic  surgery  in  a  ward  where  all  the  other  cases  are  treated 
on  the  same  principles.  Selecting  amputations  of  the  thigh  as  a  test  case, 
because  the  mortality  in  these  is  more  striking  than  in  the  other  amputations, 
the  writer  has  looked  out  all  the  cases  in  the  hospital  case-book  for  the  years 
1888-89-90  which  have  been  operated  on  by  him.  He  finds  they  amount  to 
twelve,  all  from  disease,  with  only  one  death,  and  this  was  in  an  old  man,  aged 
seventy- three,  in  whom  the  amputation  had  been  done  for  senile  ganq-rene* 
with  serious  kidney  and  arterial  disease.  This  gives  a  mortality  of  8*4  per 
cent.  It  is  true  that  the  number  of  amputations  during  these  three  years  is 
not  large, ^  but  the  writer  is  very  strongly  of  opinion  that  if  the  statistics  of 
previous  years  could  be  examined,  the  mortality  would  be  found  not  higher 
than  this.  During  the  three  years,  there  have  been  also  two  cases  of  ampu- 
tation at  the  hip-joint,  which  have  both  recovered. 

Allusion  has  been  made  to  the  great  diminution  in  the  number  of 
erysipelas  cases  in  the  surgical  wards  of  Guy's  Hospital  since  the  introduc- 
tion of  Listerism.  Dr.  Steele  has  been  kind  enough  to  obtain  for  the  writer 
the  total  number  of  cases  admitted  from  the  hospital  wards  into  the  isolation 
wards  (the  so-called  *  erysipelas  wards  ')  during  the  last  four  years.  In  round 
numbers  they  amount  to  about  twelve  a  year.  But  it  must  be  added  at  once 
that  very  few  of  these  are  erysipelas  or  blood-poisoning  cases  originating  in 
the  toard.  They  are  mostly  foul  cases  (ulcers,  gangrene,  &c.),  admitted  as 
such,  and  sent  up  at  first  into  the  general  wards,  and  thence  transferred  at 
the  surgeon's  first  visit  to  the  '  erysipelas  ward.'  On  account  of  the  limited 
accommodation  in  this  ward,  it  is  a  rule  at  Guy's  Hospital  that  no  case  is  to 
be  admitted  to  it  from,  outside,  except  under  circumstances  of  great  urgency, 
and  with  the  consent  of  the  medical  superintendent,  but  that  the  beds  are 
to  be  reserved  for  cases  occurring  in  the  hospital.  When  the  ward, 
therefore,  is  partly  empty,  the  temptation  to  the  resident  staff  to  send 
an  urgent  foul  case  into  the  general  ward,  or  even  one  which  is  already  show- 
ing signs  of  blood  poisoning,  so  that  it  may  be  passed  into  the  erysipelas 
ward,  is  very  strong,  and  this  accounts  for  the  number  of  such  cases 
admitted.  No  record  has  been  kept  in  the  '  erysipelas  ward '  (and  it  would 
be  very  difficult  for  any  Sister  to  do  so)  of  the  numbers  of  the  two  classes  of 
cases,  viz.,  those  originating  de  novo  in  the  ward,  and  those  admitted  into 
the  general  ward  as  foul  cases,  merely  for  the  sake  of  being  passed  through 
by  the  surgeon  in  the  course  of  the  first  few  days.  So  that  for  information  on 
this  head  the  writer  can  only  appeal  to  the  individual  experience  of  his  own 
ward.  In  Dr.  Steele's  return,  he  finds  that  during  the  whole  four  years 
there  were  no  cases  admitted  from  Naaman  ward  (the  male  ward),  that  there 
was  one  case  admitted  from  Charity  ward  (the  female  ward),  in  eighteen 
months,  and  one  ^  from  Accident  ward  in  two  and  a  half  years.  Neither  of 
these  cases  were  cases  originating  in  the  wards,  but  came  from  outside,  and 

*  The  writer  is  not  able  to  give  the  statistics  of  these  amputations  in  the  rears  previous 
to  1888,  owing  to  a  technical  defect  in  the  indexing  of  the  hospital  case-book,  which  has 
since  been  remedied. 

-  In  neither  of  these  wards  is  the  return  sufficiently  full  to  enable  the  writer  to  state 
the  number  in  the  full  period  of  four  years. 


800  HYGIENE 

passed  throiigh  the  ward  in  the  manner  above  described.  As  explaining  the 
total  absence  of  cases  from  Naaman  ward,  it  may  be  mentioned  that  the  beds 
are  in  great  request,  and  nearly  always  promptly  filled  by  a  fresh  case  from 
the  country  or  elsewhere  directly  one  falls  vacant,  so  that  the  resident  staff 
have  comparatively  small  chance  of  making  use  of  these  beds  in  the  manner 
before  mentioned. 

Such  a  fact  as  this  justifies  the  statement  that  Listerism  has  nearly,  if 
not  quite,  '  abohshed  erysipelas  from  our  wards.' 

Looldng  at  the  matter  from  quite  another  standpoint,  the  improved 
hygienic  condition  of  the  wards  of  large  hospitals  shows  itself  in  the 
diminished  mortality  of  the  large  lying-in  hospitals.  It  is  not  very  easy  to 
obtain  any  exact  returns  of  mortality  in  these  hospitals  in  the  years  before 
the  introduction  of  antiseptic  midwifery.  In  many  places  it  was  often  so 
high  that  no  returns  were  published,  and  it  is  probable  that  none  were  even 
kept.  But  it  may  almost  certainly  be  assumed  that  we  are  putting  it  at  a 
very  moderate  estimate  in  stating  that  the  deaths  were  80  per  1,000,  almost 
entirely  from  septic  causes,  in  the  pre-antiseptic  years.  Very  often  it  was 
much  higher  than  this.  Thus  Dr.  Cullingworth  states  in  a  lecture  delivered 
in  St.  Thomas's  Hospital  (and  reported  in  the  '  British  Medical  Journal ' 
for  October  6,  1888,  p.  743)  that  at  the  Paris  Maternite  the  mortality  from 
1858  to  18G9  amounted  to  93  per  1,000.  In  the  New  York  Maternity 
Hospital  the  deaths  amounted  to  60'6  per  1,000  from  sepsis  during  1883, 
and  in  the  Boston  Lying-in  Hospital  to  55*5  and  45*8  per  1,000  in  the  years 
1882  and  1883  respectively.  This  was  just  before  the  introduction  of  anti- 
septics into  midwifery,  and  in  both  the  last  hospitals  the  change  in  the 
mortality  is  most  striking.  Thus  in  the  New  York  Maternity  Hospital  the 
mortahty  fell  in  1884  to  5-9  per  1,000,  and  in  1885  to  1'8.  In  the  Boston 
Lying-in  Hospital  the  mortality  fell  in  1884  to  16  per  1,000,  in  1885  to  6"4> 
and  in  1886  there  were  no  deaths  from  sepsis. 

Amongst  the  English  lying-in  hospitals  the  results  at  the  General  Lying- 
in  Hospital  are  best  known,  and  most  striking.  To  quote  a  table  from  the 
same  paper  by  Dr.  Cullingworth  : — 

Table  showing  mortality  at  General  Lying-in  Hospital  from  1833  to  1887. 


Date 

Deliveries 

Deaths 

Average  mortality  per  1,000 

1833  to  1860 
1801  to  1877 
1880  to  1887 

5,838 
3,773 

2,585 

180 
64 
16 

30-8 
17 
6 

Thus  the  mortality  has  fallen  from  17  to  about  6  per  1,000  in  the 
last  septennial  period.  Even  this  does  not  represent  the  full  advantage 
obtained.  Since  1887  puerperal  fever  has  almost  entirely  disappeared. 
'  Only  one  death  has  taken  place  from  this  cause  during  the  last  three  years, 
and  it  has  come  to  be  regarded  as  quite  an  unusual  event  for  a  patient's  tem- 
perature during  convalescence  to  exceed  100°  Fahr.' 

On  the  other  hand,  it  is  not  possible  in  this  and  many  other  lying-in 
hospitals  to  obtain  full  and  accurate  statistics  of  the  exact  mortality  in  the 
pre-antiseptic  days.  '  Until  the  year  1887  this  hospital  was  scarcely  ever 
free  from  puerperal  fever,  and  the  mortality,  always  high,  occasionally 
became  fearful.  In  1838,  of  seventy-one  women  delivered,  nineteen  died ; 
in  1861,  fourteen  died  out  of  one  hundred  and  ninety-five  ;  and  in  1887,  nine 
out  of  sixty-three.     On  several  occasions  the  hospital  had  to  be  closed  for 


HOSPITAL  HYGIENE  801 

long  periods,  and  thousands  of  pounds  were  spent  on  the  sanitary  improve- 
ment of  the  building  '  (Cullingworth,  loc.  cit.). 

These  greatly  improved  results  have  been  obtained  partly  by  the  use  of 
corrosive  sublimate  lotions  (1  to  1,000)  for  the  hands,  instruments,  such  as 
catheters,  &c.,  and  corrosive  sublimate  lubricants,  e.g.,  mercuric  chloride  one 
part  dissolved  in  1,000  parts  of  glycerine  ;  partly  by  attention  to  most  of  the 
hygienic  details  enforced  in  the  previous  parts  of  this  paper.  Thus  one  of 
the  working  rules  is  to  allow  only  a  certain  number  of  confinements  to  take 
place  in  a  ward,  after  disinfection  and  cleansing  ;  thus  giving  practical  appli- 
cation to  the  remark  which  the  writer  has  already  quoted  from  the  late  Dr. 
Mahomed,  that  in  his  experience  at  the  Fever  Hospital  the  mortality  from 
scarlatina  was  always  less  in  those  wards  which  had  recently  been  re-painted 
and  cleansed. 

The  details  respecting  the  successful  working  of  the  General  Lying-in 
Hospital  have  been  recently  very  fully  given  in  a  paper  read  before  the 
Obstetrical  Society  by  Dr.  E.  Boxall,  on  '  Fever  in  Childbed '  (vide  '  Obst. 
Trans.,'  1890,  vol.  xxxii.,  pp.  264-270).  As  the  change  in  the  mortality  and 
amount  of  fever  in  this  hospital  is  so  very  remarkable,  and  as  we  possess  all 
the  main  facts  during  the  last  seven  years,  it  will  be  worth  while  to  give  the 
mode  of  successful  working,  as  stated  in  Dr.  Boxall's  paper,  the  more  so 
as  they  form  an  effective  commentary  on  much  that  has  been  already  written 
in  this  article. 

The  General  Lying-in  Hospital  is  a  small  one,  containing  only  twenty- 
four  beds.  It  is  divided  into  small  wards,  containing  only  three  and  four 
beds  each.  Thus  '  most  of  the  lying-in  wards  have  three  beds  each,  one 
rather  larger  than  the  rest  has  four,  the  convalescent  ward  four  beds,  and 
the  isolation  ward  one  bed.'  A  clear  space  of  2,000  cubic  feet  is  allowed  for 
each  bed.  There  is  a  special  '  labour  ward '  on  each  floor  for  the  reception 
of  one  or  if  occasion  require  of  two  patients. 

It  should  be  said  that  no  structural  alterations  have  been  made  in  the 
hospital  during  the  last  seven  years,  so  that  the  altered  mortality  can  only 
be  attributed  to  the  improved  method  of  working  the  hospital.  The  hospital 
was  founded  in  1765,  occupies  a  site  in  a  densely  populated  part  of  Lambeth 
called  '  The  Marsh.'  The  structural  alterations  and  sanitary  improvements, 
already  referred  to,  were  all  made  prior  to  the  last  septennial  period. 

The  wards  and  ceilings  of  the  wards  are  all  painted.  The  floors  are 
partly  polished,  but  the  old  deal  floors  were  found  unsuitable  for  this  purpose, 
so  that  with  the  exception  of  one  ward  recently  laid  with  teak,  the  old  mode 
of  cleansing  has  been  maintained. 

Closets  and  slop-sinks  are  provided  on  each  floor,  and  are  built  out  in  a 
turret  so  constructed  as  to  include  a  passage  shut  off  from  the  corridor  by 
doors,  and  ventilated  by  windows  on  each  side.  All  the  drains  are  outside 
the  building,  and,  together  with  the  soil-pipes,  are  freely  ventilated.  The  drains 
are  disconnected  from  the  main  sewer,  and  are  flushed  automatically  every 
twelve  hours. 

The  ventilation  and  warming  of  the  wards  are  practically  done  by  means 
of  open  fireplaces  and  open  windows.  Hot-air  pipes  were  laid  at  great  ex- 
pense throughout  the  hospital  some  years  ago,  and  an  outlet  ventilating 
shaft  was  provided  for  each  ward.  These,  however,  worked  so  inefficiently 
that  for  the  last  ten  years  they  have  been  discarded.  Fires  are  kept  constantly 
burning  in  the  open  grates,  and  all  the  windows  are  kept  open  at  the  top  at 
least  six  inches,  and  the  inside  Venetian  blinds  are  turned  so  as  to  direct  the  in- 
coming current  of  air  upwards.  Tobin's  tubes  are  used  in  one  ward,  where  the 
windows  are  all  on  one  side,  and  the  ventilation  is  reinforced  throughout  by 

VOL.  I.  3  F 


80-2  HYGIENE 

inlet  ventilators  near  the  floor  and  Sherringhani  valves  at  the  upper  part  of 
the  outer  wall. 

As  regards  the  important  elements  of  clothing  and  bedding,  each  lying-in 
ward  and  delivery  room  is  provided  with  its  own  set  of  instruments  and 
utensils.  Hair  mattresses  are  used.  Both  infants  and  mothers  are  provided 
with  special  clothing  during  their  stay  in  hospital,  and  the  clothing  which 
the  mothers  wore  on  entrance  is  mostly  taken  away  by  the  friends.  This 
was  necessitated  by  an  outbreak  of  scarlatina  in  the  hospital,  brought  in  from 
outside,  some  six  years  ago.  All  lamidry  work  is  contracted  for  outside  the 
hospital,  and  the  clothes  and  bedding  are  despatched  there  three  times  a 
week,  without  being  previously  disinfected  or  otherwise  treated.  But  when 
returned,  the  clothes  are  put  into  a  Fraser  stove  and  the  temperature  raised 
to  250°  Fahr. — '  more  "snth  a  view  to  airing  it  efficiently  than  of  efl'ectually 
destroying  infection.'  Up  to  three  years  ago  the  mattresses  used  also  to  be 
stoved,  but  as  it  was  found  impossible  to  keep  them  in  the  heat  for  a  suf- 
ficient time  to  destroy  all  possible  infection  without  injuring  the  fabric,  this 
was  discontinued.  '  At  the  same  time  each  mattress  was  numbered,  and  a 
register  was  instituted  of  each  patient  for  whom  it  was  used,  so  that  any 
defect  might  be  at  once  traced.  Any  mattress  which  has  been  used  for  a 
case  likely  to  infect  it  is,  however,  at  once  sent  away  in  order  to  undergo  dis- 
infection by  superheated  steam.' 

'  The  labour  wards  are  fumigated  and  washed  after  every  six  deliveries. 
The  lying-in  wards  are  disinfected  after  the  beds  have  been  once  occupied. 
When  a  ward  is  vacated  by  a  batch  of  patients,  the  bed  linen  is  removed,  but 
the  mattresses  and  blankets  are  suffered  to  remain  suspended  during  the  pro- 
cess of  fumigation  and  removed  afterwards.  Five  pounds  of  sulphur  are 
burnt  in  the  lying-in,  and  two  pounds  in  the  labour  wards.  The  ceihng, 
walls,  floor,  and  bedsteads,  &c.,  are  then  washed  down  with  carbolic  solution, 
1  in  20.  During  the  last  three  years,  the  fumigation  has  been  performed 
between  each  batch  of  patients,  the  additional  washing  between  every  other 
batch.  Before  that,  it  was  the  practice  to  fumigate,  to  wash,  and  then  to 
fumigate  again,  not  between  every  batch,  but  between  every  other  batch  of 
patients  {loc.  cit.,  p.  267). 

Nurses  in  attendance  on  cases  outside  the  hospital  are  not  permitted  to 
attend  those  in  the  hospital.  While  on  duty  within  the  hospital  both  mid- 
wives  and  nurses  are  required  to  dress  in  washing  material.  Separate  day- 
nurses  are  provided  for  each  ward,  and  a  separate  night-nurse  for  each  floor. 
The  nurses  assist  at  the  labour  cases  in  rotation. 

The  only  patients  considered  unsuitable  for  admission  are  those  with  foul 
wounds,  which  would  entail  risk  to  other  patients.  Patients  are  admitted 
by  letter ;  they  are  usually  '  more  or  less  advanced  in  labour  on  admission,  and 
are  conducted  at  once  to  the  labour  ward,  where  they  are  dressed  in  hospital 
clothes,  and  in  all  cases,  where  time  will  allow,  the  passages  are  irrigated 
with  three  quarts  of  antiseptic  solution  before  delivery,  the  douche  being 
repeated  if  the  labour  be  prolonged.  One  or  more  such  vaginal  douches  at  a 
temperatm-e  of  115°  Fahr.  are  invariably  given  after  labour  is  complete,  and 
any  considerable  tears  about  the  vulva  are  immediately  closed  by  suture.' 
Two  hours  after  delivery  the  patient  is  removed  on  a  trolley  to  the  lying-in 
ward.  A  slop  diet  only  is  allowed  until  the  bowels  have  been  freely  moved,  but 
fish  is  generally  allowed  on  the  third  day,  and  afterwards  meat.  A  liberal 
supply  of  milk  is  allowed,  but  beer  has  been  discontinued  since  1884,  as  it 
was  found  to  make  the  patients  feverish  and  uncomfortable  for  some  hours 
after  having  taken  it.     The  patient's  friends  are  allowed  to  visit  her  on  two 


HOSPITAL  HYGIENE  80a 

afternoons  in  the  week,  after  the  fifth  day,  and  the  patient  is  allowed  to  get 
up  about  the  ninth  day. 

Antiseptics  employed. — It  has  been  already  said  that  the  great  improve- 
ment in  the  sanitary  condition  of  the  hospital  dates  from  the  employment  of 
mercuric  chloride  (corrosive  sublimate)  in  the  form  of  injections,  washes,  and 
lubricants  for  the  hands  and  instruments.  Various  other  antiseptics  have, 
however,  been  used.  Permanganate  of  potassium  and  carbolic  acid  were  the 
principal  ones  immediately  prior  to  the  advent  of  the  mercuric  chloride,  and 
they  were  attended  with  a  very  considerable  measure  of  success.  But  these 
two  antiseptics  are  naturally  antagonistic  and  destructive  of  each  other,  so 
that  their  use  together  probably  diminished  the  activity  of  both.  Moreover, 
they  are  both  rather  irritating  to  the  mucous  membranes,  if  used  frequently 
as  injections,  or  if  used  for  a  long  period.  The  same  must  also  be  said  as 
regards  mercuric  chloride,  and  cases  have  occurred  of  mercurial  poisoning 
from  its  use  in  the  stronger  forms.  Probably  from  this  arises  the  fact  that 
the  solution  is  used  frequently  of  strengths  less  than  1  to  1,000.  Indeed,  the 
stronger  form  is  only  employed  as  a  first  injection,  or  when  any  special 
circumstances  arise  calling  for  its  use.  The  more  frequent  strength  employed 
afterwards  is  1  to  2,000,  and  in  some  cases  even  as  low  as  1  to  4,000.  As 
corroboration  of  its  irritant  character  on  mucous  membranes,  the  writer  has 
seen  in  surgical  cases  in  general  hospitals  the  employment  of  a  strength  of 
1  to  1,000  on  the  mucous  membrane  of  the  mouth,  rectum,  or  vagina,  for 
three  or  four  days  consecutively,  cause  great  irritation  and  inflammation  of 
those  membranes,  so  that  he  uses  it  only  very  sparingly  for  such  operations. 
On  the  other  hand,  it  appears  to  have  comparatively  little  irritant  effect  on 
freshly  cut  tissues,  so  that  it  is  more  suitable  for  wounds  than  for  use  where 
the  mucous  membranes  are  concerned. 

Partly  on  account  of  this  irritant  action  of  mercuric  chloride,  the  medical 
staff  of  the  General  Lying-in  Hospital  sought  for  some  other  antiseptic,  which 
should  not  have  the  same  irritant  quality,  while  possessing  equal  antiseptic 
value.  With  this  view  a  systematic  trial  was  given  to  salufer  (silico-fluoride 
of  sodium),  1  to  500  solutions,  as  a  part  substitute  for  the  mercuric  chloride. 
But  it  was  found  that  during  the  period  of  trial  the  number  of  cases  of 
pyrexia  during  the  pu.erperium  rose  considerably,  and  the  average  tempera- 
tures were  much  higher  than  under  the  treatment  by  mercuric  chloride,  so 
that  it  was  abandoned,  and  the  use  of  the  latter  was  resumed.  And  it  may 
be  added  that  this  is  the  antiseptic  which  is  still  almost  entirely  used,  and 
that  in  spite  of  the  occasional  occurrence  of  mercurial  poisoning,  the  risks  of 
sepsis  are  so  much  greater  than  those  of  mercurial  poisoning  that  the 
continued  use  of  the  mercuric  chloride  is  more  than  justified. 

It  must  be  allowed  that  the  patients  admitted  into  a  lying-in  hospital 
require  peculiarly  stringent  treatment  as  regards  antiseptic  precautions. 
From  the  maladies  too  often  prevalent  amongst  them,  such  as  gonorrhoea, 
syphilis,  and  various  forms  of  soft  sore,  to  say  nothing  of  their  Habihty  to 
come  from  infected  homes  where  scarlatina,  measles,  or  other  zymotic 
affections  are  raging,  such  hospitals  are  more  liable  to  outbreaks  of  puerperal 
fever  than  other  general  hospitals  are  to  erysipelas,  pyemia,  or  other  form 
of  blood-poisoning.  The  mucous  membranes  of  the  female  during  the 
puerperium  are  peculiarly  subject  to  the  absorption  of  such  poisons.  It  may 
be,  therefore,  that  some  of  the  precautions  necessary  at  such  hospitals  may 
not  be  so  necessary  at  general  hospitals.  Still  in  many  respects  the  pre- 
cautions found  absolutely  necessary  at  the  general  lying-in  hospital  might 
probably  be  imitated  advantageously  elsewhere.    Though  many  of  the  large 

3f2 


804  '  HYGIENE 

infectious  disease  hospitals  of  the  Asylums  Board,  and  others  elsewhere,  are 
most  ably  managed,  the  writer  thinks  that  there  is  room  for  improvement  m 
most  of  them  in  the  future.  The  herding  together  of  large  numbers  of  in- 
fectious cases  must  always  be  looked  upon  with  suspicion  from  a  hygienic 
point  of  \dew.  In  some  respects  such  hospitals  might  take  a  lesson  from  the 
conditions  of  healthy  working  found  essential  in  a  lying-in  hospital.  The 
Avriter  would  indicate  two  such  points  : — viz.  (1)  the  treating  of  infectious 
cases  m  small  wards,  containing  each  three  or  four  patients,  where  they  would 
pass  through  the  similar  stages  of  the  fever  at  the  same  time  ;  (2)  the  frequent 
cleansing  and  disinfection  of  such  small  wards.  This  should  be  done,  in  his 
opinion,  after  each  batch  of  patients  had  vacated  the  ward,  and  it  would  be 
rendered  possible  by  the  smaller  size  of  the  ward.  Such  disinfection  would 
probably  contribute  to  the  progress  of  the  fever  case  itself,  and  would  render 
less  likely  and  less  frequent  the  spread  of  the  fever  amongst  the  medical 
attendants  and  nurses. 


THE  DISPOSAL  OF  KEFUSE 


BY 

W.  H.  COEFIELD,  M.A.,  M.D.  (Oxon.) 

FELLOW  OF  THE  ROYAL  COLLEGE  OF  PHTSICLiNS  ;  PROFESSOR  OP  HYGIENE  AND  PDBLIO  HEALTH 

AT  TTNIVBESITY  COLTJIGE,  LONDON  ;    MEDICAL  OFFICER  OF  HEALTH  FOR  ST  GEORGES, 

HANOVER  SQUARE  ;     EX-PRESIDENT  OF  THE  SOCIETY  OF  MEDICAL 

OFFICERS  OF  HEALTH  ;  HON.  A.E.I.B.A. 

AND 

LOUIS  0.  PAEKES,  M.D.,  Dip.  Public  Health  (Lond.  Uniy.) 

FELLOW  OP  THE  SANIfARY  INSTITUTE 

ASSISTANT  PROFESSOR  OF  HYGIENE  AND    PUBLIC  HEALTH  AT  UNIVERSITY  COLLEGE,  LONDON 

LECTURER   ON  PUBLIC  HEALTH  AT  ST.  GEORGE'S  HOSPITAL 

MEDICAL  OFFICER  OF  HEALTH  AND  PUBLIC  ANALYST  FOE  CHELSEA 


THE   DISPOSAL   OF  EEFUSE 


DEFINITION 


The  refuse  of  a  community  includes  the  dry  refuse  of  the  house  (ashes, 
dust,  and  refuse  food),  the  f^ees  and  urine  of  men  and  animals  (the  excretal 
refuse),  and  the  waste  waters  from  cooking  and  washing  in  houses.  All 
these  matters  are  the  waste  products  of  the  individual  house  or  estabHsh- 
ment ;  but  in  all  towns  the  municipal  authority  must  make  arrangements 
for  the  collection,  removal,  and  disposal  of  the  liquid  and  solid  waste  sub- 
stances from  stables,  cowsheds,  and  slaughter-houses,  the  sweepings  of  the 
streets  and  markets,  and  the  waste  waters  from  works  and  factories,  in 
addition  to  the  more  strictly  domestic  waste  matters. 

Methods  of  Bemoval. — Some  of  this  refuse  material  being  in  a  more  or 
less  solid  or  dry  condition  may  be  removed  by  mechanical  labour ;  and  in 
many  towns  in  this  country  the  municipal  scavenging  department  undertakes 
the  collection  and  removal  of  the  dung  from  stables,  the  ashes,  dust,  and 
food  scraps  from  houses,  and  the  sweepings  from  the  streets  and  markets. 
In  some  towns  human  faeces  and  a  certain  amount  of  urine  are  also  removed 
by  this  method,  after  being  deposited  in  dry  closets  or  privies.  The  system 
is  still  largely  in  use  in  the  towns  of  the  midland  and  northern  counties. 
Necessarily  scavenging  operations,  as  usually  conducted,  fail  to  deal  with  any 
but  the  more  or  less  solid  refuse  ;  consequently  the  house  waste  waters,  the 
rain  water  from  roofs,  paved  yards,  and  streets,  the  liquid  drainage  from 
stables,  and  the  waste  hquors  from  manufactories,  must  be  carried  away  from 
the  houses  in  drains,  and  from  the  town  in  sewers  ;  in  other  places  the 
excretal  matters  are  collected  in  underground  cesspools,  which  are  emptied 
from  time  to  time.  These  are  known  as  the  conservancy  systems  of  excretal 
removal,  the  refuse  matters  being  necessarily  kept  for  a  certain  period  in  or 
near  to  the  house. 

Most  towns  in  this  country  have  long  been  provided  with  drains  and 
sewers  for  carrying  off  the  liquid  wastes,  and  the  rain  water  which  falls  over 
the  surface  covered  by  streets  and  buildings  ;  and  it  soon  came  to  be  recog- 
nised that  there  was  a  distinct  advantage  in  removing  the  solid  human 
excreta  as  well  in  this  manner.  For  by  carrying  these  substances  away  in 
drains  and  sewers,  the  most  offensive  and  dangerous  portions  of  the  human 
refuse  matters  were  removed  at  once  from  the  neighbourhood  of  houses,  and 
the  necessity  for  retention  on  the  house  premises,  which  is  the  very  essence 
of  all  conservancy  systems,  was  thereby  avoided.  This  system  of  removal  of 
excreta  by  water  carriage  from  the  neighbourhood  of  houses  and  to"^\Tis  is, 
where  circumstances  are  favourable  to  its  execution,  the  one  best  suited  to 
our  national  habits,  and,  sanitarily  considered,  is  far  preferable  to  any  con- 
servancy system. 


808  HYGIENE 


REMOVAL   OF   DUST,   ASHES,   AND  EEFUSE   FOOD 

Arrangements  must  be  made  by  the  sanitary  authority  for  the  removal 
of  household  dust,  ashes  and  cinders  from  fires,  scraps  of  waste  food,  and 
other  refuse  matters.  Inasmuch  as  these  substances  can  only  be  removed  at 
intervals  from  the  houses  where  they  accumulate,  it  is  important  that  they 
should  be  so  stored  and  kept  as  to  remain  inofi'ensive  during  their  period  of 
retention  on  the  premises.  The  dust  and  ashes,  being  in  great  part  mineral 
substances,  are  not  likely  to  give  rise  to  any  nuisance,  but  the  organic  matters 
contained  in  the  scraps  of  refuse  food  will  ferment,  putrefy,  and  cause 
serious  nuisance  unless  suitable  precautions  are  taken.  Obviously  the  first 
indication  is  to  limit,  as  far  as  possible,  the  quantity  of  these  waste  organic 
substances  that  must  be  stored  on  the  premises  to  await  removal  by  the 
scavengers.  In  well-organised  households  all  those  waste  matters  that  can 
be  destroyed  by  heat  may  be  burnt  in  the  kitchen  fire.  Such  as  are  in- 
destructible must  be  placed  with  the  ashes  and  dust  in  the  dustbin. 

Until  quite  recently,  dustbins  were  large  receptacles  constructed  of  brick- 
work, backing  upon  a  wall  in  the  yard,  or  against  the  side  of  the  house, 
"v\T.th  an  opening  above  protected  by  a  wooden  cover,  and  a  door  at  the  side 
for  removal  of  the  contents.  The  cover  being  liable  to  removal,  the  contents 
of  the  dustbin  were  often  exposed  to  rain ;  the  water  saturated  with  noxious 
organic  substances  penetrated  into  the  ground  or  into  the  brick  walls  of  the 
house,  against  which  the  dustbm  was  placed,  and  in  summer  the  combination 
of  heat  and  moisture  caused  rapid  decomposition  of  the  organic  substances, 
mth  evolution  of  offensive  and  injurious  gases. 

These  disadvantages  of  the  old-fashioned  brick  dustbin  have  caused  it  to 
be  largely  replaced  by  small  galvanised  iron  pails,  which  should  be  provided 
with  a  properly  fitting  metalUc  cover,  in  order  to  ensure  dryness  of  the 
contents.  If  the  contents  are  properly  dry,  fermentation  and  the  production 
of  offensive  gases  is  avoided,  even  although  the  temperature  of  the  air  is 
high.  The  iron  pails  being  non-absorbent,  their  walls  are  not  saturated  with 
foul  organic  substances  as  are  the  walls  of  brick  dustbins ;  and  being  easily 
movable  the  pails  may  be  placed  in  such  a  position  as  to  cause  least  offence 
to  the  mmates  of  the  house,  and  are  easily  carried  by  the  scavengers  to  the 
dust  cart,  into  which  their  contents  are  at  once  emptied.  In  several  parishes 
of  London  the  local  authorities  have  now  gratuitously  provided  every  house 
with  a  galvanised  iron  pail  to  replace  the  brick  or  wooden  dustbin,  and  the 
excellent  sanitary  results  of  this  system  more  than  counterbalance  the  initial 
expense. 

As  frequent  a  removal  as  possible  of  the  dustbin  contents  is  greatly  to  be 
desired.  A  daily  removal  is  what  should  be  aimed  at ;  but  this  would  involve 
considerable  expense,  and  it  is  not  usually  found  practicable  to  carry  out  more 
than  a  bi-weekly  removal.  In  many  places  the  dust  carts  only  call  nominally 
once  a  week,  and  in  reahty  at  many  houses  of  the  parish  or  district  at  even 
longer  intervals.  It  is  certamly  to  be  recommended  that  during  the  summer 
months  the  removals  should  be  effected  twice  as  often  as  in  winter. 

Specially  constructed  carts  should  be  employed  in  the  removal  of  dustbin 
refuse,  and  they  should  be  provided  with  a  cover,  to  prevent  the  diffusion 
into  the  air  of  the  streets  of  particles  of  dust,  which,  if  derived  from  a  fever- 
stricken  house,  may  be  the  means  of  scattering  infection  broadcast. 

A  list  of  the  matters  which  may  be  placed  in  the  pails  or  dustbins  for 
collection  should  be  issued  by  the  local  authority  to  every  householder.  This 
list  should  include  cinders,  ashes,  potato  peelings,  cabbage  leaves,  and  kitchen 


THE  DISPOSAL   OF  REFUSE 


809 


refuse  generally  ;  but  instructions  should  be  given  that,  wherever  possible,  as 
in  large  houses  with  good  kitchen  ranges,  kitchen  refuse  should  be  burnt. 
Trade  and  manufacturing  refuse,  refuse  building  materials,  and  garden 
sweepings  and  cuttings,  should  be  excluded  from  the  list  of  what  the  local 
authority  is  bound  to  collect. 

It  is  the  almost  universal  experience  that  the  dust  collection  is  far  more 
efficiently  performed  when  in  the  hands  of  the  local  authority,  and  worked  by 
their  own  officials,  than  when  let  out  to  contractors.  Dust  is  no  longer  a 
marketable  product  as  it  was  som«  years  ago  ;  consequently  it  is  no  longer  in 
the  interest  of  the  contractor  to  collect  as  much  as  possible  each  day,  but 
rather,  as  he  is  now  paid  to  do  what  he  formerly  paid  for  the  privilege  of 
doing,  it  is  his  interest  to  do  as  little  as  possible. 

The  ultimate  disposal  of  the  dustbin  refuse  is  a  matter  for  the  serious 
consideration  of  local  authorities.  The  old  system  still  obtains  at  many 
places  of  carrying  the  refuse  to  a  large  sorting  yard,  often  in  close  proximity 
to  inhabited  houses.  Here  men  and  women  are  employed  in  sorting  the 
refuse  and  separating  it  into  breeze  (cinders  and  small  particles  of  coal), 
hard  core  (bottles,  bones,  crockery,  metal  pots,  and  pans),  and  soft  core 


From    "  Engineering,"   January    21st,    1881. 
Pig.  162. — Fryer's  Destructor  funiace. 


(animal  and  vegetable  organic  matters  and  textile  substances).  The  breeze 
is  sold  to  brickmakers  ;  the  hard  core,  or  such  parts  of  it  as  are  worthless, 
is  used  in  road  making ;  and  the  soft  core  is  mixed  with  fish  offal,  market 
sweepings,  and  horse  droppings,  and  sent  into  the  country  to  be  sold  as 
manure.  The  whole  process  of  sorting  is  a  noxious  one,  and  degrading  to 
the  workpeople  ;  and  the  foul  odours  given  off  during  the  process,  and  also 
from  the  heaps  of  refuse  awaiting  removal,  whilst  fermentation  and  de- 
composition are  at  work,  often  prove  a  most  serious  nuisance  to  the  sur- 
rounding neighbourhood. 

More  recently  it  has  been  attempted  to  destroy  the  dustbin  refuse  in  a 
Destructor  furnace  (see  figs.  162  and  163).  The  proportion  of  cinders  in  the 
refuse  is  quite  sufficient  to  ensure  its  complete  combustion  in  a  properly 
constructed  furnace  ;  but  it  has  been  found  that  a  small  amount  of  unburned 
or  partly  burned  vapours,  and  a  very  fine  dust,  are  liable  to  be  carried  off  with 
the  products  of  combustion,  which  escape  into  the  air  from  the  chimney. 
The  unburned  vapours  impart  to  the  escaping  gases  an/)ffensive  smell,  which 
is  perceptible  to  those  living  in  the  neighbourhood  of  the  Destructor  ;  and 
the  dust  is  deposited  on  surrounding  objects,  and  becomes  also  a  subject  of 
complaint.     To  ensure  the  complete  combustion  of  the  vapours  and  dust,  a 


810 


HYGIENE 


_3f_ 


SecUoTv  at  R  s\ 


From       Engineering,"    -January 

Fig.  163. — Fryer's  Destructor  furnace. 


Cremator  furnace  may  be  introduced  at  the  foot  of  the  chimney  through 
which  all  the  smoke  from  the  Destructor  furnace  must  pass.  In  this  cre- 
mator unburned  vapom's  and  solid  particles  are  completely  burned  up  before 
they  can  enter  the  chimney  flue. 

At  Bradford  a  fume  cremator  of  this  description  (Jones's  patent)  has 
been  introduced  into  the  Destructor.'  The  gases  from  the  Destructor  furnace 

are  made  to  pass  over  a  coke  fire 
on  a  grate,  in  a  furnace  covered 
in  by  a  firebrick  arch.  The  coke 
is  fed  in  by  openings  at  the  top, 
and  the  fire  is  stoked  through 
doors  in  the  ordinary  way.  In 
this  furnace  are  a  series  of  fire- 
brick arches  or  projections,  called 
bafflers,  which  ensure  that  the 
gases  shall  not  only  be  exposed  to 
a  great  heat,  but  that  they  shall 
be  exposed  for  a  sufficiently  long 
time.  In  the  Bradford  Destruc- 
tor steam  injections  (Horsfall's 
method)  are  used  to  increase  the 
draught  in  the  furnace  of  the  De- 
structor. A  jet  of  steam  under  considerable  pressure  is  forced  underneath 
the  fire-bars  by  means  of  a  funnel  attached  to  steam  pipes  leading  from  a 
boiler,  which  is  itself  heated  by  the  combustion  of  the  refuse.  The  steam 
jet  causes  a  great  inrush  of  air,  thereby  increasing  the  draught  in  the  furnace 
and  causing  a  more  complete  combustion  of  the  refuse.  After  leaving  the 
cremator  the  gases  are  carried  under  the  boilers  and  finally  into  the  chimney, 
which  is  180  feet  in  height. 

Jones's  Fume  Cremator  is  in  use  for  the  Destructor  furnace  at  Ealing. 
Besides  consuming  the  dustbin  refuse,  this  Destructor  burns  up  the  sludge 
produced  by  chemical  treatment  of  the  sewage  of  the  town.  The  sewage 
sludge — which  is  an  unsaleable  product — after  losing  about  25  per  cent,  of 
its  moisture  by  draining,  is  mixed  with  about  two-thirds  its  volume  of  dust- 
bin refuse,  and  then  burned  in  the  furnace. 

In  other  towns  the  combustion  of  the  refuse  in  Destructor  furnaces  has 
been  made  available  for  generating  steam  in  boilers,  for  the  manufacture  of 
manure  from  human  excreta  (pail  contents),  for  driving  electric  lighting 
machinery,  and  for  other  municipal  purposes.  The  clinkers  when  withdrawn 
from  the  furnace  can  be  ground  down  in  a  mortar-mill  and  converted  into 
mortar,  bricks,  or  concrete. 

Sanitarily  considered,  the  destruction  by  heat  of  the  dustbin  refuse  is 
far  preferable  to  the  sorting  method,  and  economically,  where  circumstances 
are  favourable,  it  may  very  possibly  be  found  to  pay  expenses. 


HUMAN   EXCBETA 


The  table  on  the  next  page  (Lawes)  gives  the  average  amounts,  in  ounces, 
of  fffices  and  urine  passed  daily  by  an  adult  male  (15  to  50  years  of  age). 

Eoughly  speaking,  an  adult  male,  living  on  a  mixed  diet  of  animal  and 
vegetable  food,  may  be  assumed  to  pass  four  ounces  by  weight  daily  of 
solid  faeces,  and  45  to  50  fluid  ounces  of  urine.     Taking  all  ages  and  both 


See  paper  by  Dr.  MacLintock  in  Public  Health,  December  1889. 


THE  DISPOSAL   OF  BEFUSE 


811 


sexes,  the  daily  amount  of  excreta  per  head  of  a  mixed  population  may  be 
assumed  to  be  2*5  ounces  of  fasces  and  40  ounces  of  urine  (Parkes). 


- 

Pj'e=h 
Exeremcuts 

Dry 
Substance 

Mineral 
Matter 

Carbon 

Nitrogen 

Phosphates 

Faces      .     .     . 
Urine      .     .     . 

4-17 
46-01 

1-041 
1-735 

0-116 
0-527 

0-443 
0-53U 

0-053 

0-478 

0-0G8 
0-189 

Total     .     . 

50-18 

2-776 

'■  0-643 

0-982 

0-531 

0-257 

From  the  table  it  will  be  seen  that  human  fusees  when  fresh  contain 
about  25  per  cent,  of  dry  solids,  and  that  the  urine  contains  about  3'8  per 
cent,  of  dry  solids,  of  which  rather  more  than  half  (54  per  cent.)  is  urea.  A 
given  weight  of  feece-s  is  as  a  manure  more  valuable  than  the  same  weight  of 
urine,  in  the  proportion  of  about  10  to  G  ;  but  the  weight  of  the  urine  passed 
daily  by  an  individual  of  a  mixed  population  is  sixteen  times  as  great  as  that 
of  the  faces  ;  consequently  the  urine  passed  by  an  individual  in  twenty-four 
hours  is  worth  ten  times  as  much  as  the  faeces  passed  in  the  same  time,  the 
nitrogen  being  no  less  than  nine  times,  and  the  phosphates  nearly  three 
times,  as  much  by  weight  in  the  daily  urine  as  in  the  daily  faeces. 

Messrs.  Lawes  and  Gilbert  have  calculated  that  the  average  amount  of 
ammonia  voided  annually  by  an  individual  of  a  mixed  population  of  both 
sexes  and  all  ages  is  in  urine  11*32  lb. ;  in  faeces  1*64  lb. :  total  12-96  lb.  The 
money  value  of  the  total  constituents  (ammonia,  phosphates,  and  potash)  is 
in  urine  7s.  dd. ;  in  faces  Is.  2|(i. :  total  8s.  6|cZ.  But  in  calculating  the 
value  of  sewage  it  is  better  to  take  the  annual  excretion  of  the  individual  as 
being  equivalent  to  10  lb.  of  ammonia,  worth  6s.  8^.,  more  especially  as  it 
was  stated  by  the  late  Dr.  Voelcker  that  nitrogenous  organic  matters  (in 
which  form  the  nitrogen  of  sewage  principally  exists)  are  worth  considerably 
less  than  ready-formed  ammoniacal  salts.  It  is  also  evident  that  it  must  be 
impossible  to  realise  practically  any  such  value,  because  it  is  impossible  to 
collect  the  whole  of  the  urine  and  faeces  unmixed  with  other  substances, 
which  greatly  detract  from  the  value  because  they  are  agriculturally  worth- 
less. 


WASTE   WATEES 

The  waste  waters  from  houses  contain  much  foul  organic  matter.  The 
kitchen  sink  waters  are  highly  charged  with  decomposable  organic  matters, 
especially  grease  ;  and  the  slop-waters  contain  urine,  soap,  and  dirt  from  the 
surface  of  the  body  and  from  clothes. 

The  waste  liquors  from  manufactories  are  of  very  variable  constitution. 
Some  of  them  are  very  rich  in  manurial  ingredients — e.g.  the  waste  water 
from  flannel  washing  was  stated  by  the  Rivers  Pollution  Commissioners  to  be 
twenty  times  more  valuable  as  a  manure  than  London  sewage. 

These  waste  waters,  when  mixed  with  rain  water  from  the  roofs  of  houses 
and  from  paved  surfaces,  with  the  liquid  drainage  from  midden  pits  or  cess- 
pools, stables,  cowsheds,  and  slaughter-houses,  and  with  the  urine  from  pubhc 
urinals,  form  the  sewage  of  the  non-water-closeted  or  midden  tovnis.  Such 
sewage  from  being  stale  is  decidedly  more  offensive  than  that  of  water-closeted 
towns,  which  contains  the  solid  human  excreta  as  well.  In  the  first  report 
of  the  Eivers  Pollution  Commissioners  it  is  stated  that  there  is  '  a  remarkable 
similarity  of  composition  between  the  sewage  of  midden  towns  and  that  of 
water-closet  towns.     The  proportion  of  putrescible  organic  matter  in  solu- 


812  HYGIENE 

tion  in  the  former  is  but  slightly  less  than  in  the  latter  ;  whilst  the  organic- 
matter  in  suspension  is  somewhat  greater  in  midden  than  in  water-closet 
sewage.  For  agricultural  purposes  ten  tons  of  average  water-closet  sewage 
may,  in  round  numbers,  be  taken  to  be  equal  to  twelve  tons  of  average  privy 
sewage.'  The  same  report  also  shows  that  more  persons  contribute  to  a 
given  volume  of  sewage  in  midden  towns  than  in  water-closet  towns,  because 
it  is  found  that  the  proportion  of  chlorine  is  greater  in  the  sewage  of  the 
former  towns  than  in  that  of  the  latter,  the  cause  of  this  difference  being  the 
increased  quantity  of  water  needed  by  and  supplied  to  the  water-closet 
towns. 

Such  being  the  case,  it  is  necessary  to  bear  in  mind  that  in  towns  where 
there  are  middens,  or  some  form  of  dry  closet  for  the  collection  of  ftecal 
matters,  there  is  also  the  liquid  sewage  to  be  conveyed  away  from  the  houses 
by  drains  and  from  the  town  by  sewers,  which  sewage  is  too  impure  to  be 
admitted  into  a  stream,  and  must  therefore  be  purified  before  being  so  dis- 
charged. 


CONSERVANCY   SYSTEMS 
Middens 

Until  comparatively  recent  times  open  midden  heaps  and  pits  were,  in 
town  and  country  alike,  the  almost  universal  receptacles  for  the  excretal  and 
other  waste  matters  of  the  habitation.  On  the  midden  heaps  the  excrement 
was  allowed  to  accumulate,  and  to  diffuse  itself  from  thence  for  an  unlimited 
time,  or  until  it  was  required  for  manure.  The  disgust  excited  by  these  large 
accumulations  of  filth  above  the  surface  of  the  ground  eventually  led  to  the 
practice  of  digging  shallow  pits  in  the  yards  and  courts  about  houses,  over 
which  was  erected  some  primitive  form  of  privy.  The  intention  was  that 
the  contents  of  the  pits  should  be  removed  as  soon  as  they  were  full ;  but  too 
often  they  were  allowed  to  overflow,  when  the  filthy  liquids  found  their  way 
into  the  cellars  of  houses  or  saturated  the  ground  in  their  vicinity.  In  any 
case,  being  unprotected  from  rain,  the  water  soaked  through  the  more  or  less 
sohd  midden  contents,  and  percolating  through  the  surface  layers  of  the  soil 
poisoned  the  water  in  the  neighbouring  wells. 

The  institution  of  middens,  i.e.  the  setting  aside  of  a  special  locality  where 
the  refuse  matters  of  a  house  might  be  deposited,  was  no  doubt  an  improve- 
ment on  the  state  of  things  which  existed  in  an  even  more  primitive  condition 
of  society,  where  no  special  places  being  allotted  for  such  purposes  excrement 
was  deposited  in  any  convenient  or  inconvenient  locality.  But  the  pesti- 
lential odours  that  arose  from  the  festering  midden  heaps  and  pits,  the  pol- 
lution of  the  soil  around  the  houses,  and  the  contamination  of  the  wells,  were 
the  cause  of  much  of  that  epidemic  prevalence  of  cholera  and  fever  which 
was  characteristic  of  the  last  century  and  the  first  half  of  this,  and  which 
experience  has  shown  to  be  so  eminently  preventable  by  improved  methods  of 
excretal  disposal.  That  such  abominations  still  exist  in  many  places  in  this 
country  is  only  too  true.  The  immense  advance,  however,  in  sanitary 
enlightenment  has  already  effected  enormous  improvements,  and  it  is  hkely 
that  the  loathsome  middens  which  were  formerly  so  universal  will  soon  be 
utterly  abolished. 

Various  improvements  have  from  time  to  time  been  attempted  upon  the 
old-fashioned  form  of  midden  pit.  These  improvements  had  for  their  object 
(1)  the  removal  of  the  midden  from  the  iminediate  neighbourhood  of  the 
house  ;  (2)  a  reduction  in  the  size  of  the  pit,  so  as  to  limit  the  accumula- 


THE  DISPOSAL    OF  BEFUSE 


813 


tion  of  foul  matters,  and  the  lining  of  the  pit  walls  with  brickwork  and  cement 
so  as  to  render  them  impermeable  and  prevent  the  saturation  of  the  soil  with 
foul  liquids  ;  (3)  the  preservation  of  the  midden  contents  in  a  dry  condition 
{a)  by  roofing  over  the  pit  so  as  to  prevent  any  entry  of  rain,  (b)  by  admixture 
of  the  excreta  with  ashes,  and  (c)  by  connecting  an  overflow  pipe  with  a  sewer 
or  ditch  so  as  to  drain  off  the  more  fluid  portions. 

The  provision  of  an  overilow  pipe  to  middens  and  cesspools  when  con- 
nected with  sewers  has  been  found  productive  of  so  much  nuisance  that  it 
is  now  almost  everywhere  prohibited.  The  putrid  fluid  from  middens  thus 
introduced  into  the  sewers  carried  so  much  ashes  with  it  as  to  cause  foul 
deposits,  which  gave  rise  to  the  most  offensive  gases,  and  eventually  tended 
to  cause  a  complete  stoppage.  Besides,  if  the  middens  or  cesspools  cannot 
be  worked  without  connection  with  the  sewers,  it  is  difficult  to  see  wherein 
their  use  lies.  For  the  midden  or  cesspool  drainage  pollutes  the  sewers  to  an 
equal,  if  not  to  a  greater  extent  than  water-closets,  whilst  the  receptacles 
themselves  retain  the 
filthy  solids  on  the  pre- 
mises of  the  house,  when 
they  might  with  greater 
advantage  be  conveyed 
straight  to  the  sewers. 

Most  modern  regula- 
tions require  that  the 
midden  pit,  qua  a  hole 
dug  into  the  ground, 
should  be  abolished  alto- 
gether, and  that  for  the 
pit  should  be  substituted 
merely  the  space  inter- 
vening between  the  seat 
of  the  closet  and  the 
floor.  In  nearly  all  towns 
where  middens  are  re- 
tained they  are  now  re- 
quired to  be  constructed 
according  to  certain  defi- 
nite rules.  The  Model 
Bye-laws    of   the    Local 

Government  Board  for  the  construction  of  privies  and  middens  in  new  build- 
ings are  to  the  following  effect : — 

The  privy  (fig.  164)  must  be  at  least  six  feet  away  from  any  dwelling,  and 
forty  or  fifty  feet  away  from  any  well,  spring,  or  stream  ;  means  ot  access 
must  be  provided  for  the  scavenger,  so  that  the  filth  need  not  be  carried 
through  a  dwelUng  ;  the  privy  must  be  roofed  to  keep  out  rain,  and  provided 
with  ventilating  openings  as  near  the  top  as  practicable ;  that  part  of  the 
floor  of  the  privy  which  is  not  under  the  seat  must  be  not  less  than  six 
inches  above  the  level  of  the  adjoining  ground,  must  be  flagged  or  paved  with 
hard  tiles,  and  must  have  an  inclination  towards  the  door  of  the  privy  of 
half  an  inch  to  the  foot,  so  that  any  liquids  spilt  upon  it  may  run  outside 
and  not  fiiud  their  way  into  the  receptacle  under  the  seat ;  the  capacity  of 
the  receptacle  under  the  seat  of  the  privy  must  not  exceed  eight  cubic  feet — • 
a  weekly  removal  is  then  necessitated  ;  the  floor  of  this  receptacle  must  be 
in  every  part  at  least  three  inches  above  the  level  of  the  adjoining  ground ; 
the  sides  and  floor  of  this  receptacle  must  be  constructed  of  impermeable 


Fig.  164. — Privy  constructed  in  accordance  with  Model 
Bye-laws  of  the  Local  Government  Board. 


814 


HYGIENE 


materials  :  they  may  be  flagged  or  asphalted,  or  constijicted  of  9-incli  bricK- 
work  set  and  rendered  m  cement ;  the  seat  must  be  hinged,  or  other  means 
of  access  to  the  contents  of  the  privy  must  be  prouded ;  and  the  receptacle 
must  net  communicate  with  any  drain  or  sewBr. 

When  middens  are  constructed  according  to  these  rules,  there  is  little 
danger  of  percolation  of  liquid  filth  into  the  soil  around  houses,  and  in  the 
neighbourhood  of  wells.  The  pollution  of  the  air  by  the  excreta  is  re- 
duced to  a  minimum,  if  their  dryness  is  ensured  by  the  proper  application 
to  them  of  ashes  and  cinders,  and  no  slop-waters  are  thrown  in.  During 
removal,  however,  some  offensive  effluvia  must  of  necessity  escape  into  the 
air.  The  success  of  the  system  depends  to  a  large  extent  on  efficient  inspec- 
tion by  the  sanitary  officers,  and  on  proper  scavenging  arrangements. 

There  can  be  no  doubt,  however,  about  the  fact  that  any  form  of  midden 
is  unadvisable,  from  the  great  expense  of  scavenging  and  the  inconvenience 
caused  by  the  frequent  \dsitations  of  the  scavengers,  especially  as  they  have 
to  disturb  the  contents  of  the  middens  in  digging  them  out.  These  frequent 
visitations  are  most  unpopular,  and  any  plan  which  makes  such  visits  as 
infrequent  and  as  short  as  possible,  or  does  away  with  them  altogether,  is 
sure  to  be  greatly  preferred. 

The  Pail  System 

We  have  seen  that  middens  can  only  be  tolerated  when  so  reduced  in 
size  as  merely  to  constitute  the  space  between  the  closet  seat  and  the  floor. 
It  is  obvious  that  middens  of  this  limited  capacity  may  most  advantageously 
be  replaced  by  movable  receptacles,  such  as  pails  or  tubs,  placed  under  the 
closet  seat  for  the  reception  of  the  excreta.  The  removal  of  the  excreta  is 
thereby  greatly  facilitated,  and  there  is  no  pollution  of  the  air  from  disturb- 
ance of  the  contents  of  the  pails,  as  there  always  must  be  when  the  contents 
of  middens  are  dug  out  and  conveyed  to  the  night-soil  carts.     On  the  arrival 


Fig.  165. — Rochdale  pail. 


Fig.  166. — Rochdale  pail,  with  Haresceugh'i 
spring  lid. 


of  the  scavenger  the  lid  of  the  pail  is  adjusted,  the  pail  is  taken  out  to  the 
scavengers'  cart,  and  a  clean  empty  one  is  left  in  its  place. 

The  pails  (figs.  165  and  IGG)  may  be  of  galvanised  iron  or  tarred  oak  :  they 
should  be  provided  with  close-fitting  lids,  which  hermetically  seal  the  pails 
and  prevent  any  leakage  or  escape  of  effluvia  at  the  time  of  their  removal 
to  the  scavengers'  carts,  when  the  contents  are  unavoidably  liable  to  some 
disturbance  ;  and  the  capacity  of  each  pail  should  not  be  greater  than 
two  cubic  feet.  They  should,  of  course,  be  very  strongly  constructed,  and 
capable  of  resisting  the  rough  usage  to  which  they  may  be  subjected,  as  well 


THE  DISPOSAL   OF  BEFUSE  815 

as  be  perfectly  water-tight.  On  the  whole,  tarred  oak  pails  have  been  found 
to  answer  better  than  galvanised  iron  ones,  as  they  are  less  expensive,  last 
longer,  and  are  far  more  easily  repaired.  When  the  pails  have  been  emptied 
of  their  contents  at  the  town  depot,  they  should  be  well  washed  with  water, 
jetted  out  of  a  hose  under  high  pressure,  and  subsequently  disinfected  with 
chlorinated  lime.  Wooden  pails  require  retarring  every  two  or  three  months. 
The  structure  of  the  closet  may  be  very  similar  to  that  described  as 
recommended  for  a  midden  closet.  It  should  be  well  roofed,  the  roof  being 
provided  with  louvres  for  ridge  ventilation,  and  the  door  should  be  so  con- 
structed that,  when  closed,  open  spaces  may  be  left  above  and  below  for  light 
and  ventilation.  The  floor  should  be  raised  above  the  level  of  the  adjoin- 
ing ground  and  flagged,  and  the  pail  placed  on  the  floor  under  the  seat.  The 
seat  may  be  hinged  to  ensure  a  more  complete  covering  of  the  excreta  with 
house  cinders  and  ashes,  when  these  are  used,  and  to  allow  of  the  pail  being 
removed  ;  or  the  back  wall  of  the  closet  may  be  provided  with  a  door  to  effect 
the  latter  purpose.  The  pail  should  be  removed  at  not  longer  intervals 
than  once  a  week,  and  a  clean  one  substituted  for  it,  this  plan  being  far 
preferable  to  that  of  emptying  the  pail  contents  into  the  night-soil  cart,  and 
then  replacing  the  pail  after  a  more  or  less  perfunctory  attempt  to  clean  it. 

From  a  sanitary  point  of  view  it  is  most  important  that  the  pail  contents 
(fffices  and  urine  passed  at  the  time  of  evacuation)  should  be  kept  as  dry  as 
possible.  A  dry  condition  can  only  be  effected  by  adding  to  the  pail  contents 
some  dry  and  absorbent  substance  such  as  ashes,  charcoal,  or  dry  earth,  or 
by  lining  the  pail  with  some  absorbent  material.  Left  to  themselves,  the 
mixed  fseces  and  urine  in  the  pails  are  in  a  more  or  less  liquid  condition, 
and  rapidly  tend  to  undergo  putrefactive  changes,  giving  rise  to  the  forma- 
tion of  fo3tid  gases  (organic  vapours  and  compounds  of  sulphur  and  ammonia). 
If,  however,  it  is  intended  to  create  a  saleable  manure,  ashes,  charcoal,  or 
earth  should  not  be  used,  and  all  kitchen  refuse  and  garbage  should  be  kept 
out  of  the  pails,  as  it  is  most  essential  to  collect  the  faeces  and  urine  in 
as  pure  a  condition  (i.e.,  unmixed  with  valueless  substances)  as  possible.  In 
such  cases  the  pail  contents  cannot  be  kept  dry,  and  sanitary  considerations 
are  sacrificed  to  ensure  commercial  profits. 

In  some  towns,  such  as  Nottingham,  the  authorities  find  it  convenient  to 
remove  all  the  solid  house  refuse  in  one  receptacle,  so  that  the  pails  become 
the  receptacles  for  the  solid  kitchen  refuse,  dust  and  ashes,  as  well  as  for 
the  excreta.  Here,  of  course,  commercial  profit  from  the  sale  of  manure  is 
not  looked  for,  but  the  town  being  situated  in  the  centre  of  an  agricultural 
district  there  is  no  difficulty  in  disposing  of  the  manure,  such  as  it  is. 

By  keeping  the  chamber  urine  out  of  the  pails,  much  fertilising  material 
is  excluded,  as  the  chamber  urine  constitutes  at  least  nine-tenths  of  the- 
total  daily  excretion  of  urine.  But  it  would  be  impossible  to  keep  the  pail 
contents  dry  if  chamber  slops  were  thrown  in,  and  these  must,  therefore,  be 
carried  away  from  the  houses  in  drains  with  the  other  waste  waters.  It  has 
even  been  attempted  to  separate  the  urine  passed  at  the  time  of  evacuation 
from  the  faeces,  in  order  to  ensure  dryness  of  the  pail  contents.  These 
'  urine- separators  '  have,  however,  not  been  found  to  answer  their  purpose, 
and  they  are  more  especially  undesirable,  inasmuch  as  they  introduce  a  com- 
plication into  a  system  the  chief  merit  of  which  is  its  simplicity. 

In  the  Goux  system  it  is  attempted  to  secure  dryness  of  the  excreta  by 
lining  a  wooden  tub  (fig.  167)  with  a  layer  of  refuse  sawdust,  shoddy,  tan,  or 
other  absorbent  material,  to  which  is  added  a  little  soot,  charcoal,  gypsum, 
or  other  dryer  or  deodoriser.  These  matters  are  pressed  closely  to  the  bottom 
and  sides  of  the  tub  by  means  of  a  cylindrical  mould  (fig.  lG8j,  which  is  after- 


816 


HYGIENE 


1'  8" 


wards  witbdrawn.  leaving  a  ca%-ity  in  the  centre  of  tlie  materials  for  the 
reception  of  the  excreta.  On  no  accoimt  should  chamber  slops  be  thrown 
into  the  tubs,  and  the  tubs  themselves  should  only  be  in  use  for  two  or  three 
days,  otherwise  the  absorptive  capacity  of  the  lining  materials  is  exceeded, 

and  the  tubs  will  be 
found  to  contain  liquid 
dejections.  The  sys- 
tem has  been  in  use 
at  Halifax,  and  on 
the  whole  has  worked 
well,  the  closets,  when 
well  managed,  being 
generally  found  clean 
and  free  from  otieusive 
smells.  House  ashes 
and  dry  rubbish  are 
collected  in  a  separate 
pail,  so  that  the  tub 
contents  are  merely  the  excreta  in  a  more  or  less  pure  condition. 

As  before  stated,  another  method  to  ensure  the  dryness  of  the  excreta  is 
the  addition  of  ashes,  charcoal,  or  dry  earth  m  suitable  quantities  to  the 
contents  of  the  pails  after  each  use  of  the  closet.     These  substances  not 


-Goux  pail 


Fig.  108.— Goux  mould. 


Monncu.*  IptrcNT.  of  IU«7 


^ S-of —  —  -<i 

Fig.  169. — Morrell's  cinder-sifting  ash  closet.     The  soil  pail  is  removed  through  a  side  wall- 

only  act  as  dryers,  but  very  largely  also  as  deodorisers,  so  that  ash,  charcoal, 
or  earth  closets,  if  rightly  used,  are  far  less  offensive  than  the  pail  closets 
where  these  substances  are  not  in  use. 

Ash  Closets 

Sifted  house  cinders  and  ashes  may  be  collected  in  a  box  and 
thrown  by  a  handscoop  into  the  pail  after  each  use  of  the  closet ;  or  by 
a  mechanical   arrangement  of  sieves  fixed  in  a  hopper  placed  above  and 


THE  DISPOSAL   OF  BEFUSE 


817 


behind  the  pail,  the  cinders  may  be  sifted  and  the  fine  ash  deposited  auto- 
matically on  the  pail  contents  by  means  of  a  self-acting  seat  arrangement, 
or  the  same  result  may  be  accomplished  by  pulling  up  a  handle  (figs.  IGD 
and  170).  The  cinders  which 
do  not  pass  through  the  sifter 
may  be  used  again  as  fuel. 
When  properly  sifted,  the  fine 
ashes  form  very  efficient  de- 
siccators and  deodorisers  ; 
moreover,  they  are  always 
to  be  found  on  the  premises 
of  any  house,  unlike  charcoal 
or  dried  and  sifted  earth,  anrl 
they  would  have  to  be  removed 
in  any  case  by  the  sanitary 
authority. 

Charcoal  Closets 


Fig.  170. — External  view  of  Morrell'B  ash  closet,  show- 
ing opening,  a,  for  putting  in  ashes,  and  door,  b,  for 
removing  sifted  cinders.  A  door  may  be  made  at  c 
for  removing  the  soil  pail. 


Wood  charcoal  and  a  char- 
coal obtained  by  carbonising 
sea-weed  have  been  used  instead 

of  ashes.  The  same  kind  of  closet,  with  an  automatic  apparatus  for  supply- 
ing the  charcoal,  is  suitable  as  for  the  ash  closet,  or  a  box  and  scoop  may 
be  used.  Of  the  sea- weed  charcoal  (Stanford's  process)  it  is  stated  that  only 
•^Ib.  is  necessary  for  each  use  of  the  closet,  and  this  is  found  to  be  equiva- 
lent in  deodorising  power  to  1^  lb.  of  dry  earth.  The  charcoal  itself  contains 
63  per  cent,  of  carbon,  34  per  cent,  of  ash,  and  only  2"6  per  cent,  of  water. 
On  removal  from  the  closet  the  mixed  charcoal  and  excrement  may  be  re- 
carbonised  by  burning,  and  may  then  be  again  used  for  the  same  purpose. 
The  products  of  distillation  from  the  recarbonisation  process  when  condensed 
consist  of  ammoniacal  liquor  and  tar,  and  from  the  liquor  sulphate  of  am- 
monium and  acetate  of  potassium  can  be  obtained.  After  several  uses  in 
the  closet  the  charcoal  becomes  highly  chargecl  with  potash  and  phosphates, 
and  when  mixed  with  the  ammonia  distilled  from  it  forms  a  very  valuable 
manure. 

Neither  charcoal  nor  ashes  have  any  such  disintegrating  action  on  the 
excreta,  as  we  shall  see  further  on  the  dry  earth  has.  A  section  through 
the  contents  of  an  ash  or  charcoal  closet  pail  shows  the  excrement  retaining 
its  form,  and  the  paper  unchanged,  but  the  whole  mass  is  dry  and  odourless. 
Nevertheless  any  assumption  that  mixed  excrement  and  charcoal  or  ashes 
may  for  this  reason  be  safely  stored  for  long  periods  of  time  in  the  vicinity, 
or  within  the  precincts,  of  houses  would  be  entirely  unwarranted.  The 
only  safe  plan  is  to  arrange  for  as  frequent  removal  of  the  contents  of  ash 
and  charcoal  closets  as  of  the  simpler  pail  closets. 

There  can  be  little  doubt  that  Stanford's  sea-weed  charcoal  is  far  more 
efficient  than  ordinary  sifted  house  ashes.  On  the  other  hand,  a  system  of 
charcoal  closets  would  be  far  more  costly  to  maintain.  There  is  the  cost  of 
manufacture  of  the  charcoal  and  its  conveyance  to  every  house,  and  this  is 
likely  to  greatly  exceed  any  returns  that  may  be  obtained  by  distilling  the 
mixed  excrement  and  charcoal  and  selling  the  products  so  obtained. 

In  order  to  deodorise  the  contents  of  pails  in  which  excreta  are  collected, 
it  has  been  proposed  to  add  a  mixture  of  soot  and  salt,  which  has  been  fomid 
very  effective  for  this  purpose,  although  its  drying  action  is  practically  nil, 

VOL.  I.  3  G 


818 


EYGIEXE 


Fig.  171. — Stove  for  drying  earth. 


Eaeth  Closets 

It  has  long  been  known  that  earth  of  suitable  quality  is  a  very  efficient 
deodoriser  of^excremental  matters.  For  centuries  past  the  Chinese  have 
been  accustomed  to  collect  with  extreme  care  all  human  excremental  matters, 
and  to  convey  them  to  their  fields  for  enriching  the  earth,  knowing  tis  they 

do  the  valuable  fertilising 
ingredients  contained  in  the 
excreta.  And  in  this  custom, 
originated  ])y  the  thoughtful 
thrift  for  which  the  Chinese 
are  famous,  is  also  contained 
the  practical  application  of 
the  sanitary  rule,  '  the  sew- 
age to  the  soil,' which  is  the 
highest  development  of  our 
most  enlightened  views  on 
the  utilisation  of  human 
refuse.  Not  only  is  the 
earth  the  better  for  the 
sewage,  which  returns  to  it  in  an  assimilable  form  the  nitrogen  and  inorganic 
salts  taken  away  in  the  crops,  but  on  a  large  scale  the  earth  is  the  only  sub- 
stance available  for  converting  the  noxious  products  of  human  and  animal 
excretion  into  inoffensive  and  useful  matters. 

The  dry  earth  system,  the  invention  of  the  late  Rev.  Henry  Moule,  is, 
however,  the  very  reverse  of  the  plan  upon  which  all  the  other  systems  pro- 
ceed.    It  proposes  to  bring  a  certain  quantity  of  earth  to  the  manure,  while 

all  the  others  take  the  manure  in  some 
form  or  another  to  be  placed  upon  the 
earth  ;  in  other  words,  a  sufficient  quan- 
tity of  dry  earth  is  to  be  brought  into 
every  community  where  this  system  is  at 
work,  to  completely  deodorise  and  render 
inoffensive  all  the  excremental  matters  of 
the  population. 

The  best  kinds  of  earth  for  the  pur- 
pose  are  loamy   surface   soil,  vegetable 
mould,  brick  earth,  and  dry  clay.    Sandy, 
gravelly,  and  chalky  soils  are  not  efficient 
deodorisers.      The  earth  must  be  dried 
before  use  over  a  stove  (fig.  171)  or  on  a 
hot   floor,   and   then  passed   through   a 
riddle  or  sieve  (fig.  172),  so  as  to  thoroughly 
sift  it,  the  finer  portions  only  being  used. 
For  large  communities  these  operations 
should  be  conducted  at  one  spot,  and  on 
.  an  extensive  scale  ;  but  for  separate  esta- 
blishments, such  as  houses  or  institutions 
in   the   country,  each   household  would 
have  to  prepare  its  own  earth. 
The  excreta  are  deposited  in  a  pit  of  an  approved  sort,  or  in  a  pail  (fig.  173) 
or  tub  placed  under  the  closet  seat,   and  1|  lb.  of  dried  sifted  earth  must 
be    applied   in    detail— i.e.   each    particular    stool    must    be    covered    at 
once   with  this  quantity  as  soon  as  deposited.     This  quantity  (1^  lb.)  is 


Fig.  172.— Earth-sifter. 


THE  DISPOSAL   OF  BE  FUSE 


819 


sufficient  to  remove  all  'omell  from  the  stool,  and  to  form  a  compost  with  it 
which  remains  inoffensive  as  long  as  it  is  dry.  Less  earth  than  the  above 
•specified  amount  is  said  to  be  insufficient, 
whilst  more  is  useless.  A  certain  action  takes 
place  in  the  intimate  mixture  of  earth  and 
•excrement  which  results  in  the  complete  dis- 
integration of  the  faBcal  matters.  After  a 
time,  excremental  matters,  and  even  paper,  can 
no  longer  be  detected  as  such  in  the  mixture. 
After  keeping  and  redrying  the  compost  so 
formed,  it  may  be  used  over  again  in  the 
closet,  and  has  the  same  action  as  the  original 
dry  earth ;  but  inasmuch  as  this  repeated  use 
does  not  increase  in  a  corresponding  degree 
the  manurial  value  of  the  compost,  there  is  no 
particular  advantage  in  doing  so  from  an  Pig.  173.— Pail  holding  twenty  charges. 
economical  point  of  view,  if  we  except  the 

reduction  in  bulk  of  the  matters  that  eventually  require  removal  from  the 
house,  which  is  only  a  matter  of  importance  in  the  case  of  towns,  and  does 
not  apply  with  equal  force  to  country  houses. 

The  closet  suitable  for  the  earth  system  may  be  very  similar  to  that 
described  under  ash  closets.  A  hopper  of  metal  or  wood  is  placed  above 
and  behind  the  seat,  and  the  requisite  quantity  of  dry  earth  is  shot  into  the  pit 
or  pail  by  a  simple  mechanical  contrivance  connected  with  a  handle  (fig.  174) 
or  self-acting  seat  ar- 
rangement. 

In  large  establish- 
ments the  tank  shown  in 
fig.  175  can  be  used.  It 
holds  thirty- six  charges, 
■  and  being  on  wheels  is 
more  easily  removed 
than  a  pail  holding  the 
same  amount.  It  is 
especially  useful  for 
schools,  barracks,  fac- 
tories, &c.,  where  the 
closets  are  much  used, 
and  where  smaller  pails 
might  in  the  course  of 
a  day  become  overfilled. 
The  contents  of  the 
pails  must  be  kept  dry, 
or  fermentation  results 
with  the  disengagement 
of  foul  gases  ;  conse- 
quently no  slop  waters  must  be  thrown  into  them,  and  even  chamber  urine 
must  be  excluded  unless  sufficient  extra  earth  is  added  to  render  the  contents 
quite  dry. 

The  compost  produced  by  the  passage  of  the  earth  even  five  or  six  times 
through  the  closet  has  but  little  agricultural  value  as  a  manure.  The 
British  Association  Sewage  Committee  reported  of  such  manure  that  it  was 
'  no  richer  than  good  garden  mould.'  The  committee  found  that  the  average 
gain  of  total  nitrogen  to  the  soil  by  each  passage  through  the  closet  was 

3g2 


Fig.  174. — Earth  closet,  with  pull-up  handle  apparatus. 


820 


HYGIENE 


scarcely  O'lii  per  cent. ;  and  they  remark  upon  this  point  that  '  if  only  two 
pounds  of  soil  were  used  per  head  per  day,  and  as  much  as  one-third  of  the 
total  nitrogen  voided  in  fieces  and  urine  by  an  average  individual  in  twenty- 
four  hours  were  collected  with  it  in  the  closet,  the  nitrogen  so  added  to  the 
soil  would  amount  to  about  0-5  per  cent,  of  its  weight  by  each  use,  or  by 
using  five  times  to  nearly  2-y  per  cent.  Probably  in  practice  a  larger  amount 
of  soil  and  a  smaller  proportion  of  the  total  nitrogen  daily  voided  would  be 
collected  in  an  earth  closet.  The  increased  percentage  of  nitrogen  actually 
found  is  seen  to  be  less  than  one-third  of  the  amount  calculated  on  the 
foregoing  assumption.  There  can  indeed  be  httle  doubt  that  there  is  a 
considerable  evolution  of  nitrogen  in  some  form  ;  and  the  probability  is 
that  it  takes  place  to  a  great  extent  as  free  nitrogen.' 

This  escape  of  nitrogen  in  a  free  state  from  the  manure  when  kept  may 
partly  account  for  its  deficiency  in  fertilising  properties  ;  but  it  must  also 
be  recollected  that  the  compost  is  largely  diluted  with  valueless  earth,  and 
that  there  is  absent  from  it  a  large  proportion  of  the  daily  urine  of  each 
individual. 

The  late  Dr.  Voelcker  estimated  the  value  of  the  soil  passed  five  times 
through  the  closet  at  75.  Qd.  per  ton,  and  it  is  certain  that  it  would  only  pay 

the  cost  of  carriage  to  a  very  short 
distance,  even  if  disposed  of  free  of 
charge. 

Although  the  commercial  value 
of  the  earth-closet  manure  is  so  small, 
it  is  found  of  considerable  use  in 
gardens,  whei'e  it  can  be  applied 
■v\dthout  going  to  the  expense  of  any 
carriage.  It  forms  a  rich  mould, 
suitable  for  garden  and  pot  plants, 
and  yet  not  so  rich  that  it  has  to  be 
diluted  with  ordinary  earth.  In 
country  houses  with  gardens,  there- 
fore, the  earth  compost  has  a  con- 
siderable practical  value. 
From  a  sanitary  point  of  view  the  earth  closet  is  superior  to  any  other 
fonn  of  pail  closet.  When  properly  managed,  the  closet  is  free  from  any 
offence  ;  the  process  of  emptying  the  pails  is  unaccompanied  by  any  foul 
smells  ;  and  the  system  is  one  which  may  be  adopted  in  country  houses  and 
villages,  where  earth  of  suitable  quality  is  easily  procurable,  and  where  the 
compost  can  be  applied  on  the  spot  to  fields  or  garden  lands.  It  is,  however, 
especially  applicable  for  temporary  gatherings,  such  as  fairs  and  camps.  It 
was,  indeed,  in  use  at  the  annual  Volunteer  meetings  at  Wimbledon  for 
some  years,  and  answered  very  well. 


Pig.  175. — Tauk  liolding  thirty-six  charges. 


Manufacture  of  Manure 

We  have  already  seen  that  the  earth-closet  manure  requires  no 
further  manipulation  after  removal  from  the  closets,  but  can  be  applied 
direct  to  land.  It  is  somewhat  difi"erent,  however,  with  the  crude  contents 
of  middens  and  pails.  In  some  towns  situated  in  agricultural  districts, 
where  there  is  a  demand  in  the  immediate  locality  for  the  coarser  sorts  of 
manure,  the  contents  of  middens  or  pails  need  merely  be  mixed  with  a 
certain  portion  of  fine  ash,  when  farmers  in  the  neighbourhood  are  willing 
to  remove  it.     This  manure  is,  however,  only  well  suited  for  heavy  clay 


THE  DISPOSAL   OF  BE  FUSE  821 

soils ;  for  most  soils  the  admixture  with  ashes  renders  it  comparatively 
•worthless. 

In  many  of  our  large  towns  where  the  midden  or  pail  systems  are  still 
in  vogue,  it  has  become  the  practice  of  recent  years  to  convert  the  crude  pail 
•or  midden  contents  (without  admixture  with  ashes)  into  a  dry  manure  of  a 
much  less  offensive  character,  which  can  be  packed  in  bags  or  casks,  and  sold 
at  a  distance. 

The  following  account  of  the  process,  as  usually  carried  out,  is  taken 
from  a  report  (1881)  of  Dr.  W.  Sedgwick  Saunders  upon  '  Some  new  Methods 
of  Disposing  of  all  Kinds  of  Eefuse  by  Cremation.' 

The  ashes,  &c.,  collected  in  tubs  are  screened  in  an  automatic  cinder 
screen ;  the  fine  ash  is  mixed  with  such  portion  of  pail  contents  as  will 
furnish  a  manure  sufficient  to  satisfy  the  local  demand ;  the  coarse  ash  is 
discharged  into  a  form  of  furnace  called  a  '  destructor,'  which  is  made  to 
destroy  and  reduce  any  refuse  material  that  contains  only  a  small  portion  of 
combustible  matter.  The  heat  generated  by  the  combustion  passes  under 
and  through  a  multitubular  boiler,  and  generates  steam  for  furnishing  the 
power  required  for  working  the  whole  of  the  machinery.  The  clinkers  from 
the  destructor,  if  not  required  for  other  purposes,  are  passed  into  a  mortar 
mill,  which  reduces  them  to  powder  that  can  either  be  sold  as  sand  or  made, 
by  the  addition  of  lime,  into  an  excellent  and  tenacious  mortar. 

The  sweepings  from  the  markets  and  streets  are  passed  through  a  '  car- 
boniser,'  a  furnace  which  converts  all  vegetable  material  into  charcoal.  The 
charcoal  produced  is  a  powerful  deodorant ;  and  it  was  proposed  to  use  a 
portion  of  it  in  each  pail,  previous  to  its  leaving  the  depot,  to  deodorise  the 
matter  collected,  the  remainder  to  be  sold. 

The  contents  of  the  pails  are  mixed  with  a  small  portion  of  acid,  to  fix  the 
ammonia,  in  an  air-tight  store  tank,  where  the  thicker  portion  of  the  material 
settles  to  the  bottom.  The  thin  part  of  the  contents  of  the  tank  is  drawn 
off  into  two  evaporators,  which  are  tall  cast-iron  cylinders,  each  containing, 
near  its  lower  end,  a  drum-shaped  heater,  precisely  resembling  a  multi- 
tubular steam  boiler.  These  cylinders  are  partially  filled,  and  the  heating 
drums  are  covered  with  the  thin  liquid ;  steam  is  then  introduced  within  the 
heating  drums,  and  the  liquid  becomes  partially  concentrated.  When  the 
contents  of  these  cylinders  are  sufficiently  concentrated,  and  have  lost,  by 
evaporation,  the  greater  portion  of  their  water,  they  are  drawn  off  into  a 
'  Firman's  dryer,'  and  the  thick  portions  of  the  pail  contents  which  settle  in 
the  store  tank  are  also  admitted  into  the  dryer.  This  machine  consists  of  a 
steam -jacketed  horizontal  cylinder,  traversed  by  a  steam -heated  axis  and  by 
steam-heated  revolving  arms,  and  is  furnished  with  scrapers  to  keep  the 
inner  surface  of  the  cylinder  free  from  accumulations  of  dried  excreta. 

The  pail  contents  are  admitted  into  the  dryer  at  the  consistency  of  thin 
mud ;  after  treatment  they  emerge  as  a  dry  powder,  resembling  guano  in 
appearance  and  quality,  and  estimated  by  analysis  to  be  worth  from  31. 
to  61.  per  ton.  The  odorous  gases  given  off  during  the  process  are  all 
passed  through  the  Destructor  furnace  and  destroyed.  From  the  time 
the  liquid  material  enters  the  store  tank,  until  it  finally  emerges  as  a 
dry  powder,  there  is  no  opportunity  for  odour  to  escape  into  the  air,  as  it  is 
kept  closely  under  cover. 

The  destructor  and  the  carboniser  are  the  inventions  of  Mr.  Alfred  Fryer, 
■who  also  originated  the  system  by  which  the  collected  ashes  and  cinders 
are  alone  sufficient  to  furnish  the  heat  necessary  to  evaporate  the  pail 
•contents. 

At  Manchester  a  portion  of  the  town  refuse  is  dealt  with  in  this  manner 


822  HYGIENE 

at  the  Corporation's  sanitary  works  at  Holt  Town.  The  cinders  collected 
are  mainly  used  as  fuel  for  the  furnaces  of  the  boilers  which  work  the- 
machinery,  effect  the  evaporations,  etc.;  the  animal  matters  are  converted 
uito  dry  manure,  soap,  and  lubricating  grease ;  and  the  clinkers  fi'om  the 
fui-nace  are  made  into  mortar,  bricks,  and  concrete.  The  animal  matters 
from  which  the  manure  is  made  include  human  excreta  (pail  contents),, 
slaughter-house  refuse,  bones,  dead  animals,  fish,  &c.  This  manure  con- 
tains 2-73  per  cent,  of  ammonia,  2-3G  per  cent,  of  phosphoric  acid,  and  15 
per  cent,  of  moisture.     It  is  sold  at  3/.  per  ton. 

Systems  similar  to  the  above  are  now  in  operation  at  Cilasgow,  Leeds, 
Bradford,  Warrington,  Rochdale,  Stafford,  Bolton,  Birmingham,  Blackburn, 
Rotherham,  Derby,  Bury,  and  Nottingham. 

The  deputation  from  the  Commissioners  of  Sewers  of  the  City  of  London 
which  visited  the  works  established  at  Leeds,  Bradford,  Warrington,  and 
Manchester  in  1881,  came  to  the  unanimous  conclusion  that  the  system  is- 
sound  in  theory  and  desirable  in  practice,  and  that  it  offered  enormous 
advantages  upon  sanitary  grounds.  '  Not  only  did  they  see  a  work  consist- 
ing of  poisonous  and  disgusting  elements  dealt  with,  and  satisfactorily  dis- 
posed of,  without  nuisance  of  any  kind,  but  learnt  that  products  having  a 
marketable  value  can  be,  and  are,  produced  without  any  infraction  of  true 
hygienic  principles,  whilst  at  the  same  time  they  may  have  the  effect  of 
materially  reducing  the  expenses  '  (Dr.  Saunders'  Report). 


Cesspools 

Until  lately  the  terms  '  midden  pit '  and  '  cesspool '  were  regarded  as 
synonymous.  But  it  has  now  become  more  usually  the  practice  to  apply 
the  term  '  cesspool '  to  those  receptacles  excavated  in  the  soil  which  are 
destined  to  receive  the  Hquid  waste  waters  of  the  house  as  well  as  the 
excreta,  whilst  the  '  midden  '  is  the  pit  for  the  reception  of  excrement  only,  or 
of  excrement  and  solid  rubbish,  the  waste  waters  being  got  rid  of  by  other 
means.  Under  the  primitive  conditions  which  existed  in  nearly  all  towns 
until  within  the  last  forty  or  fifty  years,  the  waste  waters  of  the  houses  in 
the  poorer  streets  (the  slops  and  kitchen  waters)  were  thrown  into  the  street 
gutters,  which  carried  them  away  to  the  nearest  watercourse.  In  more 
recent  times,  since  the  introduction  of  drains  and  sewers,  the  house  waste 
waters  of  the  midden  towns  are  now  conveyed  to  the  sewers  by  slop  sinks 
and  gully  holes  connected  with  a  drain.  The  midden  pits  still  remain  for 
the  reception  of  the  more  or  less  solid  refuse  of  the  house. 

It  is  therefore  obvious  that,  whereas  the  contents  of  middens  are,  or 
should  be,  in  a  more  or  less  solid  condition,  the  contents  of  cesspools  must 
necessarily  be  in  a  liquid  condition,  the  volume  of  the  liquids  they  receive 
preponderating  so  immensely  over  that  of  the  solids. 

Prior  to  the  year  1815,  when  the  law  which  prohibited  the  passage  of 
sewage  from  houses  into  the  sewers  was  repealed,  in  London  and  other  large 
towns  nearly  every  house  in  the  wealthier  streets  had  one  or  more  cesspools 
on  its  premises  for  the  reception  of  solid  and  liquid  excreta  and  waste  waters. 
These  cesspools  were  often  of  large  size,  and  situated  under  the  basements 
of  the  houses.  When,  in  the  year  1847,  it  became  compulsory  to  drain 
houses  mto  the  sewers,  many  of  these  cesspools  were  filled  in  and  abolished ; 
but  some  of  them  escaped  observation,  and  to  the  present  day  it  is  no 
imusual  thing  to  find  in  the  basements  of  town  houses  one  or  more  cesspools,, 
of  the  existence  of  which  the  owners  or  occupiers  are  profoundly  ignorant. 

At  the  present  day  cesspools  are  still  largely  in  use,  and  fresh  ones  are 


THE  DISPOSAL   OF  BEFUSE  823 

being  constantly  constructed  for  isolated  houses  in  suburban  and  country 
districts  where  there  are  no  sewers.  In  these  houses,  inside  water-closets 
are  insisted  on  by  tenants  of  the  better  class,  so  that  the  cesspools,  which  are 
excavated  in  the  yard  or  garden  adjoining  the  house,  become  the  receptacles 
for  the  water-closet  sewage  and  for  waste  waters  of  the  house. 

The  desirability  or  otherwise  of  cesspools  depends  greatly  upon  circum- 
stances. For  country  houses  with  large  gardens  the  cesspool  system  offers 
some  advantages.  If  a  series  of  two  or  three  cesspools  are  constructed 
communicating  with  each  other  by  overflow  pipes,  most  of  the  solids  are 
retained  in  the  first  of  the  series  which  receives  the  house  drain.  The  over- 
flow cesspools  receive  the  liquid  sewage,  which  can  from  time  to  time,  as 
desired,  be  pumped  up  and  used  as  liquid  manure  for  kitchen  gardens,  orchards, 
&c.  The  solids  very  gradually  accumulate  in  the  first  cesspool,  from  which, 
when  full,  they  can  be  extracted  by  buckets  and  dug  into  the  ground.  All  the 
cesspools  should  of  course  be  constructed  so  as  to  be  impermeable  to  fluids, 
and  even  then  should  be  at  a  considerable  distance  from  any  well  ;  and  in  no 
case  should  they  be  provided  with  an  overflow  pipe  to  carry  surplus  sewage 
into  a  stream  supplying  drinking  water.  Perhaps  a  better  plan  is  to  inter- 
cept the  solids  in  the  sewage  before  it  arrives  at  the  cesspool  by  placing  a 
strainer  in  a  manhole  chamber  on  the  drain.  The  most  offensive  matter 
is  thus  entirely  kept  out  of  the  cesspool,  and  can  be  dug  into  the  ground 
as  soon  as  collected,  the  collection  taking  place  daily. 

Where,  however,  houses  are  more  closely  crowded  together,  and  the  plot 
of  land  attached  to  each  is  of  size  insufficient  to  utilise  the  sewage  by  its 
application  to  the  soil,  the  cesspool  system  is  liable  to  become  an  unmiti- 
gated nuisance.  The  periodical  visitations  of  the  night-soil  carts  become 
then  a  necessity.  If  in  a  sufficiently  liquid  state,  the  cesspool  contents  are 
pumped  up  by  manual  labour  into  troughs  and  so  conveyed  to  the  carts,  or,  if 
too  solid  for  pumping,  the  contents  must  be  drawn  up  in  buckets.  In  either 
case  the  pollution  of  the  air  is  nauseating  and  disgusting  to  a  degree,  and  the 
offensive  odours  are  wafted  by  the  wind  to  considerable  distances,  so  that  all 
the  inhabitants  of  the  neighbourhood  become  aware  of  what  is  in  progress. 

There  are  also  other  very  distinct  dangers  attached  to  the  cesspool 
system.  Cesspools  are  very  frequently  so  constructed  as  to  allow  all  the 
liquid  filth  to  percolate  through  their  walls  into  the  surrounding  soil,  the 
solids  only  being  retained.  In  unlined  cesspools  dug  in  porous  soils,  such 
as  sand,  gravel,  and  chalk,  the  liquids  escape  with  the  greatest  readiness,  and 
the  cesspool  but  very  rarely  requires  emptying.  This  is  an  advantage,  how- 
ever, which  is  far  more  than  counterbalanced  by  the  contamination  of  the 
subsoil  in  the  close  vicinity  of  houses,  and  by  the  almost  certain  danger  of 
polluting .  wells,  springs,  and  other  sources  of  underground  water  supply. 
Such  pollution  is  especially  likely  to  occur  in  the  case  of  cesspools  dug  in  the 
chalk.  The  liquids  rapidly  drain  away  through  the  cracks  and  fissures  in 
the  chalk  walls,  and  even  the  solids  disappear,  with  the  result  of  polluting 
the  water  below  in  the  subterranean  reservoirs — a  water  which  is  naturally 
of  very  great  purity.  In  the  case  of  sand  and  gravel,  a  cesspool  is  exceed- 
ingly likely  to  contaminate  the  surface  wells  in  the  neighbourhood. 

The  model  bye -laws  of  the  Local  Government  Board  for  new  buildings 
require  that  the  cesspool  shou.ld  be  at  least  50  ft.  away  from  a  dwelling,  and 
60  to  80  ft.  distant  from  a  well,  spring,  or  stream.  It  must  have  no  com- 
munication with  a  drain  or  sewer  in  sewered  districts  ;  its  walls  and  floor 
must  be  constructed  of  good  brickwork  in  cement,  rendered  inside  with 
cement,  and  with  a  backing  of  at  least  9  inches  of  well  puddled  clay  around 
and  beneath  the  brickwork.  The  top  of  the  cesspool  should  be  arched  over, 
and  means  of  ventilation  provided. 


821  HYGIENE 

The  object  of  these  rules  is  to  secure  an  impenuoable  receptacle  for  the 
reception  of  the  sewage,  which  will  prevent  pollution  of  the  subsoil  and  of 
underground  water  supplies.  The  reasons  for  not  connecting  a  cesspool 
with  a  sewer  by  means  of  an  overflow  pipe  have  already  been  alluded  to 
(see  p.  813). 

Constructed  in  accordance  with  these  rules,  the  possible  dangers  of  cess- 
pools are  reduced  to  a  minimum  ;  but  the  principle,  which  is  bad,  remains 
the  same,  for  it  cannot  be  too  strongly  insisted  on  that  in  the  vicinity  of 
houses  to  retain  in  any  receptacle,  however  well  constructed,  a  large  collec- 
tion of  solid  and  hquid  excrement,  there  to  undergo  putrefaction  with  the 
formation  of  ofiensive  gases,  is  a  violation  of  every  sound  sanitary  principle. 

COXTINENTAL    SYSTEMS 

In  many  Continental  towns  the  cesspool  system  is  still  largely  adhered 
to.  Huge  pits  [fosses  iKrmancntcs)  are  excavated  under  the  courtyards  of 
the  houses,  and  are  lined  with  cement,  so  as  to  be  impervious.  In  Paris  and 
some  other  towns  these  cesspools  must  be  provided  with  a  ventilating  shaft 
reaching  up  some  feet  above  the  roof  of  the  house.  Sometimes  two  recep- 
tacles are  constructed  side  by  side,  and  communicating  with  each  other  by 
means  of  small  apertures  through  which  liquids  only  can  pass.  By  this 
means  the  solids  are  retained  in  one  receptacle,  whilst  the  liquids  pass  into 
the  other  ;  and  this  separation  is  fomid  to  materially  retard  decomposition. 
Each  of  the  receptacles  is  provided  with  a  ventilating  pipe. 

The  closets  are  usually  connected  directly  with  the  cesspool  by  means  of 
the  soil-pipe,  starting  from  the  soil-pan,  when  there  is  one,  or  from  the  hole 
in  the  lead  or  zinc-lined  floor  of  the  closet,  when  there  is  not.  There  is  often 
no  sort  of  trap  at  either  extremity  of  the  soil-pipe,  so  that  the  putrid  gases 
formed  in  the  cesspool  rise  up  into  the  interior  of  the  house.  The  soil-pan 
and  pipe  are  usually  only  flushed  Avhen  slops  are  thrown  down. 

As  a  general  rule,  the  cesspools  are  constructed  of  such  a  size  that  they 
only  require  to  be  emptied  once  in  three  or  four  months.  As  a  matter  of 
fact,  being  but  rarely  impervious,  they  allow  some  of  their  liquid  contents  to 
escape  mto  the  surrounding  soil,  and  so  only  require  emptying  at  even  longer 
intervals. 

Until  recently  the  cesspools  were  emptied  by  pumping  their  contents 
through  hose  into  large  cask-shaped  carts  {tonneaux)  sent  for  the  purpose  at 
night  when  required.  The  nuisance  engendered  by  this  process  has  now 
caused  it  to  be  largely  superseded  in  Paris,  Eheims,  Metz,  and  other  Conti- 
nental towns,  by  a  method  of  emptying  the  cesspools  by  pneumatic  pressure. 

One  of  these  methods  which  is  coming  largely  into  use  is  that  designed 
by  Talard.  A  steam  vacuum  pump  is  attached  to  a  small  portable  locomotive 
engine,  to  exhaust  the  air  from  the  receiver  or  tonneau.  These  receivers  are 
barrel-shaped,  of  a  capacity  of  about  3^  cubic  yards,  and  are  made  of  light 
steel  plates.  Each  receiver  is  mounted  on  framework  on  four  wheels,  and 
can  be  easily  drawn  from  place  to  place  by  a  pair  of  horses.  It  is  fitted  with 
a  glass  gauge  at  one  side  to  show  how  full  it  is,  and  has  a  large  full-way 
valve  underneath,  to  which  a  strong  flexible  5-inch  tube  is  attached. 

On  the  cesspool  being  opened  this  tube  is  plunged  to  the  bottom  of  the 
contents,  its  other  end  being  connected  with  the  receiver,  which  has  itself 
already  been  connected  with  the  engine  by  a  smaller  tube  from  its  upper 
part.  The  engine  being  started,  the  noxious  gases  are  first  extracted  from 
the  cesspool,  passed  through  the  furnace  and  burnt ;  the  air  is  then  exhausted 
from  the  receiver,  and  on  the  valve  being  opened  the  contents  of  the  cesspool 


THE  DISPOSAL   OF  REFUSE  825 

rusli  up,  filling  the  vacuum  in  about  three  or  four  minutes.  The  valve  is 
then  closed,  the  pipes  disconnected,  and  the  receiver  taken  away  to  be  re- 
placed by  others,  until  the  cesspool  is  entirely  empty.  It  is  stated  that  by 
this  process  the  contents  of  a  cesspool  can  be  extracted  at  the  rate  of  about 
twenty  cubic  yards  per  hour. 

The  receivers  can  either  be  discharged  into  close  barges,  specially  con- 
structed for  the  purpose,  in  which  case  the  pipe  is  connected  at  one  end  to 
the  receiver  and  at  the  other  to  the  barge,  so  that  the  contents  are  transferred 
from  one  receptacle  to  the  other  by  gravitation,  without  being  exposed  to 
the  air  ;  or  they  can  be  emptied  on  to  the  land  in  the  usual  manner  for 
fertilising  purposes. 

The  special  feature  of  Talard's  system  as  distinguished  from  other  pneu- 
matic processes  is  the  invention  of  a  mechanical  joint  to  connect  the  lengths 
of  hose.  This  joint  is  both  water-  and  air-tight,  and  can  be  made  in  two  or 
three  seconds  by  an  ordinary  labourer,  and  as  easily  disconnected. 

There  can  be  little  doubt  but  that  the  pneumatic  system  has  most 
materially  diminished  the  nuisance  formerly  inseparable  from  the  process  of 
emptying.  Not  only  was  it  obnoxious  to  all  in  the  neighbourhood,  but  the 
foul  gases  generated  by  the  disturbance  of  the  contents  of  the  cesspool  were 
a  distinct  danger  to  the  workmen.  Asphyxial  poisoning  {le  pLomh  des 
vidangeurs)  from  great  excess  of  sulphuretted  hydrogen  and  corresponding 
diminution  of  oxygen  was  occasionally  the  result  of  their  operations,  more 
especially  where  the  contents  had  to  be  raised  in  buckets  to  the  surface  ; 
and  the  Paris  scavengers  were  described  by  Parent  Duchatelet  as  suffering 
much  from  headaches  and  ophthalmia,  which  latter  {la  mitte  des  vidangeurs) 
is  generally  attributed  to  the  large  amount  of  ammoniacal  compounds  present 
in  the  foul  air. 

Movable  tubs  or  pails  {fosses  mobiles)  are  also  in  use  in  some  Continental 
towns.  As  a  rule,  the  tub  or  tonneau,  capable  of  holding  fifty  or  sixty  gallons  of 
liquid,  is  placed  in  the  basement,  and  is  connected  with  the  closets  above  by 
means  of  an  iron  or  stoneware  soil-pipe.  The  tub  is  fitted  with  a  spring  lid, 
which  is  adjusted  when  the  tub  is  full,  before  its  removal  by  the  scavengers. 
As  with  the  fosses  permanentes,  there  are,  as  a  rule,  no  traps  or  valves  fixed 
anywhere  to  prevent  foul  gases  rising  into  the  house.  Eeliance  is  placed 
upon  a  ventilation  pipe  which  is  connected  with  the  soil-pipe,  and  carried  up 
to  the  roof,  and  upon  the  lid  to  the  closet,  which,  being  constructed  with  a 
rim  fitting  into  a  groove  in  the  soil  pan,  is  supposed  to  be  air-tight.  As  a 
matter  of  fact,  however,  foul  gases  find  an  easy  exit  into  the  house  when  the 
closet  is  in  use  and  the  lid  is  raised.  In  some  cases  the  fosses  mobiles  are 
provided  with  separators  for  the  separation  of  the  liquids  from  the  solids, 
and  it  is  then  usual  to  carry  the  liquid  contents  into  a  cesspool. 

In  Paris  the  contents  of  the  fosses  permanentes  and  fosses  mobiles  are 
converted  into  manure  (;poudrette)  by  a  process  which  would  hardly  be  tole- 
rated in  this  country.  The  tonneaux  are  carried  away  to  the  works  outside 
the  town,  where  they  are  emptied  into  the  highest  of  a  series  of  basins 
ranged  one  above  another.  Here  they  are  exposed  to  the  air  for  some  time, 
and  while  the  liquid  parts  run  away  into  the  lower  basins,  the  undissolved 
solids  subside  in  the  higher  ones.  The  liquids  are  reduced  in  quantity  by 
spontaneous  evaporation,  but  they  have  for  the  most  part  to  be  pumped 
away,  generally  into  the  nearest  watercourse.  The  solid  part  which  subsides 
is  dug  out  of  the  pits,  further  dried  by  being  spread  out  on  a  large  surface 
of  ground,  and  stirred  about  continually,  piled  up  when  nearly  dry  in  im- 
mense heaps,  and  left  for  a  year  at  least — often  for  several  years.  It  is  then 
sold  under  the  name  of  pondrette.     It  has  the  aspect  of  a  greyish-black 


82G  HYGIENE 

earth,  light,  oily  to  the  touch,  very  pliable,  and  spreading  a  peculiar,  dis- 
agreeable, and  nauseous  odour. 

It  will  be  readily  understood  that  this  process  of  spontaneous  evaporation 
of  moisture  from  immense  heaps  of  putrid  refuse  must  spread  the  effluvia 
for  miles  around,  and  cause  a  nuisance,  compared  with  which  the  worst 
mana<^ed  of  our  sewage  works  would  be  described  as  inoffensive. 


COMPARISON   OF   CONSERVANCY   :\IETHODS 

From  what -has  already  been  written  on  this  subject  it  will  be  apparent 
that  the  best  system  from  a  sanitary  point  of  view  is  that  which  provides  tlie 
most  perfect  means  for  preventing  the  decomposition  of  the  excretal  matters 
during  their  period  of  retention  on  the  house  premises,  and  secures  their 
removal  with  the  greatest  frequency  and  with  the  least  offence. 

The  midden  system,  even  with  middens  constructed  on  the  best  approved 
plan,  stands  condemned  by  reason  of  the  nuisance  engendered  when  their 
contents  are  removed.  The  same  remark  appUes.with  even  stronger  force  to 
cesspools,  especially  in  towns. 

"We  are  therefore  entitled  to  insist  upon  some  form  of  movable  receptacle 
in  which  excretal  matters  may  be  collected  and  removed,  and  practical  ex- 
perience and  theory  alike  point  to  the  pail  system  as  the  conservancy  system 
which  is  best  suited  for  use  in  towns. 

Where  pails  are  in  use  the  removal  may  be  carried  out  twice  or  three 
times  a  week  ;  there  is  no  necessity  for  the  pail  contents  to  be  disturbed  until 
they  arrive  at  the  depot,  and  consequently  nuisance  in  the  neighbourhood  of 
houses  is,  to  a  considerable  extent,  avoided,  if  the  removal  is  sufficiently 
frequent.  There  is,  besides,  another  advantage  which  movable  pails  have 
over  fixed  receptacles.  Where  compulsory  notification  of  infectious  disease 
is  in  force,  the  local  authority  receive  early  information  of  cases  of  enteric 
fever.  The  pails  removed  from  infected  houses  can  be  marked,  their  contents 
disinfected,  and  clean  pails  containing  strong  chemical  solutions  supphed  in 
their  place.  In  this  manner  it  will  be  possible  to  destroy  much  of  the  poison 
excreted  by  a  case  of  enteric  fever,  and  very  materially  to  place  a  limit  on  its 
spread. 

We  have  already  seen  that  to  keep  the  pail  contents  in  a  dry  and  inoffen- 
sive condition  some  desiccating  material  must  be  added,  but  that  to  convert 
the  pail  contents  into  a  profitable  manure  they  ought  to  be  collected  unmixed 
with  other  substances.  The  great  difficulty  in  getting  rid  of  the  crude  pail 
contents  when  mixed  with  ashes  has  induced  numerous  towns  to  essay  the 
manufacture  of  manure  ;  but  we  are  strongly  of  opinion  that  that  system 
which  gives  the  best  sanitary  results  is  likely  in  the  long  run  to  prove  the 
cheapest,  and  that  admixture  with  ashes  is  one  of  the  best  methods  to  secure 
this  end. 

It  must  be  obvious  that  in  towns  ashes  are  the  only  deodorants  Avhich  are 
in  any  way  practicable.  They  are  part  of  the  domestic  refuse  of  every  house, 
and  would  have  to  be  removed  in  any  case,  and  their  preparation  by  sifting 
involves  but  very  little  trouble,  even  if  cinder-silting  ash  closets  are  not  in 
use.  The  quantity  of  dried  and  sifted  earth  that  AS'ould  have  to  be  brought 
into  a  town,  were  earth  closets  in  general  use,  would  be  enormous.  Then, 
in  every  house  accommodation  must  be  provided  for  storing  the  earth  and  for 
keeping  it  dry,  and  if  the  earth  is  to  be  used  more  than  once  the  compost 
must  be  stored  on  the  premises  and  be  again  dried  before  use.  The  quantity 
of  matter  to  be  removed  from  the  houses  by  the  local  authority  would  be 


THE  DISPOSAL   OF  BE  FUSE  827 

far  in  excess  of  that  of  the  pail  and  ashes  system,  and  when  collected  its 
value  for  fertilising  purposes  is  so  low  that  there  would  be  even  a  difficulty 
of  disposing  of  it  if  given  away,  for  it  would  not  pay  to  remove  it. 

Although,  then,  in  towns  where  a  conservancy  system  is  unavoidable 
ash  closets  appear  to  best  meet  the  requirements,  it  must  not  be  forgotten 
that  the  success  of  this  system  depends  largely  on  individual  care  on  the 
part  of  the  householder,  upon  active  sanitary  inspection  by  the  local  authority, 
and  upon  a  well-organised  scheme  of  scavenging — in  fact,  upon  arrangements 
of  considerable  complexity,  which  are  liable  to  failure  at  unexpected  times 
and  from  unexpected  causes.  The  expenses  of  this  form  of  scavenging  are 
very  high,  and  the  more  frequently  the  pails  are  removed  the  greater  is  the 
cost,  so  that  there  is  always  an  inducement  to  economise  at  the  expense  of 
health.  The  pail  system  can  be  made  to  depart  most  from  the  principle  of 
the  conservancy  method,  i.e.  the  retention  of  oxcretal  matters  on  the  premises 
of  houses,  by  adopting  a  plan  of  very  frequent  removals,  but  practically  the 
excessive  cost  of  such  a  plan  is  found  to  be  prohibitory. 

The  other  great  objection  to  all  conservancy  systems  is  the  fact  that  they 
only  deal  with  a  fraction  of  the  waste  matters  of  a  community,  and  fail  to 
deal  with  a  liquid  refuse  of  a  highly  polluting  character,  a  liquid  which 
causes  the  sewage  of  the  so-called  midden  towns  to  be  little,  if  any,  less  impure 
than  that  of  water-closet  towns  ;  and  so  conservancy  entirely  fails  to  provide 
any  sort  of  solution  to  the  question  of  disposal  of  sewage. 

Neither  can  it  be  denied  that  dry  closets  of  all  kinds  are  not  regarded 
with  favour  when  placed  inside  houses.  To  most  people  the  retention  of 
excrement  in  any  form  within  the  house  is  objectionable,  and  this  view  of  the 
matter  cannot  be  regarded  as  a  mere  prejudice.  We  are  not  yet  in  a  position 
to  assert  in  any  way  positively  that  excreta,  even  if  fairly  deodorised  by  dry 
earth  or  ashes,  are  under  all  circumstances  innocuous.  And,  besides,  there 
is  always  the  possible  danger  of  slops  being  carelessly  thrown  into  the  dry 
closet,  when  but  a  short  time  would  be  required  to  convert  what  was  before 
fairly  tolerable  into  a  most  intolerable  nuisance.  On  the  whole,  then,  we 
must  conclude  that  dry  closets  are  not  applicable  within  houses,  and  that  they 
should  invariably  be  placed  outside  the  house  in  such  a  position  that  a  free 
current  of  air  can  always  traverse  the  space  between  them  and  the  house. 


THE   WATEE-CAEEIAGE    SYSTEM 

By  this  system  is  meant  that  all  the  human  excretal  matters  of  the  com- 
munity— solid  as  well  as  liquid — are,  together  with  the  waste  waters,  con- 
veyed away  from  the  houses  in  drains,  and  from  the  town  in  sewers.  The 
force  which  conveys  them  is  gravitation,  and  this  is  enabled  to  exert  its 
power  by  reason  of  the  liquid  condition  of  the  sewage.  The  solids  of  the 
sewage,  whether  solid  excreta  or  solid  waste  particles  contained  in  the  house 
waters,  are  so  insignificant  in  volume  in  comparison  with  the  liquids  that 
they  are  carried  along  with  ease  in  the  flowing  current.  No  additional 
water  is  required  to  enable  the  liquid  wastes  of  the  house  to  carry  with  them 
the  solid  excreta ;  but  in  order  to  render  the  passage  of  the  latter,  when 
deposited  in  water-closets,  as  quick  and  perfect  as  possible,  and  also  to  ensure 
cleanliness  of  the  water-closet  apparatus,  soil  pipes,  and  drains,  water  is  used 
to  flush  these  receptacles  and  to  carry  the  excrement  rapidly  away  down 
the  soil  drains  into  the  street  sewer. 

By  this  system,  therefore,  there  need  be  no  retention  of  excretal  matters 
on  the  house  premises.     Its  leading  principle  is  to  convey  them  away  front 


828  HYGIENE 

the  house,  and  subsequently  from  the  town,  as  quickly  as  flowing  water  will 
do  it.  This  is  the  great  contrast  between  the  water-carriage  and  all  conser- 
vancy systems  ;  but,  besides  this,  it  is  evident  that  the  force  employed  in 
water  carriage,  viz.  gravitation,  costs  nothing,  whereas  the  manual  operations 
of  scavenging  removal  in  the  conservancy  systems  are  very  costly. 

We  have  already  seen  that  every  town  must  have  a  system  of  sewers  for 
conveyuig  away  the  waste  waters  from  the  houses  and  streets,  and  that  these 
waste  w^aters  are  of  very  nearly  as  objectionable  and  polluting  a  character  as 
if  they  contained  the  solid  human  excreta.  It  therefore  follows  that  what- 
ever precautions  are  necessary  to  be  taken  in  the  construction  and  main- 
tenance of  the  sewers  of  water-closeted  towns,  and  whatever  means  require 
to  be  adopted  for  the  purification  of  the  sewage  of  the  latter  before  discharge, 
apply  with  nearly  equal  force  to  the  case  of  the  midden  towns,  whose  sewage 
is  to  a  great  extent  free  from  the  solid  faeces. 

Neither  need  there  be  any  question  of  increasing  the  capacity  of  the  sewers 
of  a  midden  town  which  has  adopted  water-closets. 

Sewers,  as  originally  laid,  Avere  intended  principally  to  carry  off  the  rain 
and  surface  waters  from  roofs,  yards,  and  streets,  and  their  size  was  entirely 
regulated  by  the  volume  of  these  waters  which  they  might  be  called  upon  to 
receive  at  any  time,  such  as  during  heavy  storms  of  rain.  The  sudden  rush 
of  water  into  the  sewers  during  and  after  a  heavy  shower  far  exceeds  in 
volume  the  maximum  daily  flow  of  foul  water  from  the  houses  with  which 
they  are  connected.  And  even  were  it  not  so,  the  entire  excreta  of  a  town 
population,  in  comparison  with  the  waste  water  of  the  population,  is  only,  by 
volume,  as  about  one  to  a  hundred  ;  whilst  the  additional  water  required  for 
flushing  water-closets  and  sewers — though  varying  with  the  state  of  the 
latter  and  the  habits  of  the  people — could  not,  in  comparison  with  the  total 
volume  of  sew^age,  be  called  large. 

The  water-carriage  system,  then,  in  the  simplest  way  possible  renders 
unnecessary  the  difficulties  and  dangers  which  are  inherent  to  the  conservancy 
systems,  and  its  adoption  in  towns  only  demands  the  greater  perfection  of 
sanitary  works  (sewers  and  drains)  which  are  already  necessary,  and  in  most 
cases  already  exist. 

Water  carriage  is,  of  course,  not  possible  under  all  circumstances  ;  towns 
which  have  a  very  inadequate  water  supply  may  not  be  able  to  aft'ord  the 
increased  amount  of  water  required  to  flush  water-closets,  drains,  and  sewers, 
and  keep  them  in  good  condition.  Or,  again,  towns  standing  at  a  very  low 
level  may  be  unable  to  secure  the  gradients  required  to  lay  a  system  of 
gra\itating  sewers  to  a  possible  or  desirable  outfall.  In  this  latter  case, 
however,  the  erection  of  pumping  machinery  actuated  by  steam  or  compressed 
air  is  usually  capable  of  solving  the  problem. 


SEWEKS 

As  before  stated,  sewers  in  this  country  were  originally  designed  to  carry 
ofl:"  rainfall  and  surface  waters.  At  a  somewhat  later  period  the  drains  from 
houses  were  connected  with  them,  so  that  they  received  in  addition  the  house 
waste  waters ;  and  in  some  cases  the  overflow-pipes  from  midden  pits  and 
cesspools  were  also  carried  into  them,  by  wliicli  means  they  received  an 
accession  of  foul  and  putrid  liquids,  often  mingled  with  ashes,  which  tended 
to  choke  them  with  sediment  of  a  most  offensive  character.  Still  more 
recently  in  many  towais  these  sewers  have  also  become  the  receptacles  for 
the  water-closet   sewage  of  numerous  houses.     This  subsequent  usage  not 


THE  DISPOSAL  OF  BE  FUSE 


829 


being  in  any  way  warranted  by  their  original  design,  wliicli  was  to  carry 
off  water  2^ur  et  simple,  it  is  not  surprising  that  tlioy  fail  to  perform  the 
functions  now  allotted  to  them,  and  are  in  many  instances  the  sources 
of  nuisance  and  injury  to  health  from  causes  which  we  shall  presently 
indicate. 

As  originally  constructed  in  various  towns  in  this  country,  the  sewers 
were  laid  at  considerable  depths  below  the  surface,  and  were  made  of  brick. 
In  shape  they  were  rectangular  (fig.  170),  or  with  arched  roof  instead  of  flat 
top,  but  some  were  circular  or  oval.  At  various  points,  catchpits  from  the 
roadway  delivered  into  tliern,  and  at  convenient  spots  they  discharged  into  a 
stream,  river,  or  ditch.  Being  constructed  of  porous  bricks,  they  admitted 
subsoil  water,  and  thus  had  considerable  effect  in  securing  the  drainage  and 
drying  of  the  soil.  No  great  stress  was  laid  upon  their  having  good  gradients, 
as  they  Avere  only  intended  for  rain  water,  and,  being  usually  of  considerable 
size,  there  was  no  difficulty  anticipated  in  removing  by  manual  labour  such 
sediment  as  might  collect  in  them. 

Used  in  this  manner  as  channels  for  water  containing  but  few  solids  in 


Pig.  176.^ — Brick  square  sewer  with  stone  top. 


suspension,  these  sewer  drains  acted  fairly  efficiently.  Their  effect  in  lowering 
the  level  of  the  subsoil  water  and  drying  the  ground  beneath  and  around 
houses  was  an  especially  important  one.  Those  diseases  which  are  associated 
with  dampness  and  moisture  of  the  soil — ague,  rheumatism,  bronchitis,  &c.— 
have  been  considerably  lessened  by  works  of  drainage  ;  but  the  great  reduc- 
tion in  the  death-rate  from  phthisis  resulting  from  the  subsoil  drainage 
of  those  towns  which  formerly  were  situated  upon  waterlogged  or  moisture- 
laden  soils,  was  a  result  as  satisfactory  as  it  was  unlooked  for.  In  some 
towns  where  the  sewerage  works  have  caused  a  considerable  fall  in  level  of 
the  subsoil  water,  which  formerly  stood  within  a  very  few  feet  of  the  surface, 
the  deaths  from  phthisis  have  even  been  reduced  by  a  third,  and  in  one  case 
by  a  half,  of  what  they  had  previously  been. 

The  great  disadvantages,  however,  attending  pervious  sewers  soon  became 
realised  when  they  became  the  recipients  of  the  foul  waters  and  excretal 
refuse  from  houses.  Wherever  the  gradients  of  the  sewers  were  insufficient 
for  a  proper  flow,  or  where  the  invert  of  a  portion  of  a  sewer  had  sunk  below 
its  original  level,  owing  to  faulty  workmanship  or  want  of  a  proper  foundation, 
the  stagnant  sewage  deposited  its  suspended  particles,  and  accumulations  of 


830  HYGIENE 

offensive  sediment  were  the  result.  O^Ying  to  the  porosity  of  the  bricks  much 
of  the  water  percolated  through  the  walls  of  the  sewers  to  pollute  the  sub- 
soil water  and  contaminate  the  ground  air  ;  and  this  escape  of  the  water,  by 
withdrawing  the  vehicle  in  which  the  solids  of  the  sewage  ought  to  have 
been  suspended,  tended  to  aggravate  the  deposit  of  the  latter  on  the  floor  of 
the  sewer,  and  often  resulted  in  its  complete  choking  and  obstruction. 
Manual  labour  had  to  be  employed  to  clear  the  sewers  and  remove  from 
them  the  accumulated  deposits.  Great  expense  was  thereby  incurred,  and 
the  foul  condition  of  the  sewers  was  often  a  source  of  considerable  danger  to 
the  men  engaged  in  this  scavenging  work.  The  foul  gases,  too,  generated  by 
the  putrid  sediment  and  stagnant  pools  of  sewage,  escaped  through  the  street 
ventilators — if  there  were  any — or  else  found  their  way  into  houses  through 
drain  connections  and  trapped  or  untrapped  openings. 

The  pollution  of  the  subsoil  with  the  foul  liquids  that  percolated  through 
the  walls  of  the  sewers  resulted  in  contamination  of  the  water  in  neighbouring 
wells,  and  in  some  cases  the  water  supply  of  an  entire  community  has  been 
endangered  by  the  entrance  of  such  foul  matters  into  the  water  mains  during 
intermissions  in  the  service. 

In  some  towns  the  old  drain-sewers  still  perform  the  double  function  of 
draining  the  subsoil  and  conveying  away  the  surface  waters  and  sewage.  In 
these  places  the  evils  described  as  inseparable  from  defective  sewers  are 
always  present  in  a  greater  or  lesser  degree.  Foul  sewer  emanations  into 
the  streets  and  houses,  polluted  wells,  and  contaminated  ground  air,  exercise 
a  pernicious  influence  on  the  health  of  the  inhabitants,  and  such  diseases 
as  enteric  fever,  diarrhoea,  and  diphtheria  tend  to  become  endemic  and  to 
exhibit  epidemic  outbursts  during  favourable  seasons. 

In  many  towns,  however,  in  this  country  the  old  defective  drain-sewers 
have  been  largely  reconstructed  of  proper  materials  and  of  proper  size, 
shape,  and  fall,  but  still  receive  as  before  both  storm  waters  and  sewage  on 
what  is  known  as  the  combined  system  {tout  d  Vegout).  In  other  towns, 
again,  new  pipe  sewers  have  been  laid  to  receive  the  house  waste  waters  and 
water-closet  sewage,  whilst  the  old  drain  sewers  still  perform  their  original 
functions  as  dryers  of  the  subsoil  and  carriers  of  rain  water.  This  has  been 
termed  the  separate  system  of  sewerage,  and  was  first  prominently  brought  into 
notice  in  this  country  by  Mr.  Menzies.  It  has  since  been  adopted  in  the 
United  States  by  Colonel  Waring. 

The  Combined  System 

In  modern  systems  of  sewerage  the  chief  principles  involved  are  (1)  the  con- 
struction of  sewers  with  impermeable  materials,  so  as  to  prevent,  or  very 
greatly  limit,  the  percolation  of  polluting  liquids  through  their  walls  mto  the 
surrounding  soil ;  (2)  the  rendering  of  the  sewers  self- cleansing  by  construct- 
ing them  with  sufficient  gradients,  and  of  a  size  suitable  to  the  volume  of 
seAvage  which  they  will  ordinarily  be  required  to  carry ;  (3)  the  adoption  of 
effectual  means  for  flushing  and  ventilating  the  sewers. 

In  the  construction  of  brick  sewers,  well-burnt,  tough,  impervious  bricks 
should  be  used  ;  and  for  the  lowest  segment,  or  invert  of  the  sewer,  glazed 
firebricks,  or  suitably  curved  stoneware  blocks,  are  found  advantageous.  The 
floor  or  invert  of  the  sewer  being  the  part  most  liable  to  wear  and  erosion 
from  the  passage  of  the  suspended  matters  in  the  sewage  over  it,  it  is  highly 
important  that  it  should  be  constructed  of  very  smooth,  hard,  and  wear- 
resisting  material.  The  stoneware  invert  blocks  are  occasionally  made  hollow, 
and  they  then  provide  a  means  of  draining  off"  the  subsoil  water  during  the 


THE  DISPOSAL    OF  BE B' USE 


831 


construction  of  the  sewerage  works  ;  but  inasmuch  as  these  hollow  blocks  often 
lead  to  settlement  of  the  sewer  in  sandy  soils  from  sand  being  washed  into 
them  and  carried  away,  and  as  they  are  apt  to  split  from  the  weight  of  the 
sewer  built  over  them,  they  are  not  now  looked  upon  with  favour  by  engineers. 
Small  sewers  under  8  feet  in  diameter,  when  laid  in  good  ground,  may  be 
constructed  of  4^-inch  brickwork,  but  the  bricks  used  should  be  curved  to 
suit  the  shape  of  the  sewer  when  completed.  Nine-inch  brickwork  should  be 
used  for  larger  sewers,  or  for  the  small  sewers  when  laid  in  bad  ground  or 
shifting  sand.  The  cement  used  in  jointing  the  bricks  should  be  a  mixture 
of  clean  sharp  sand  and  best  Portland  cement  in  the  proportion  of  two  parts 
of  the  former  to  one  of  the  latter.  Portland  cement  is  a  mixture  of  chalk 
and  clay  burnt  at  a  h-igh  temperature,  and  subsequently  ground  very  fine. 
It  is  stronger  and  capable  of 

bearing  greater  tensile  strains  ^^-N^'V; 

than  other  cements,  but  does 
not  set  so  rapidly. 

Sewers  with  an  internal 
•diameter  over  18  inches  are 
now  usually  constructed 
oval  or  egg- sharped  in  sec- 
tion, with  the  smaller  end 
•downwards  (fig.  177).  The 
volume  of  sewage  flowing 
through  a  sewer  necessarily 
undergoes  very  great  fluctua- 
tions from  day  to  day,  and 
even  from  hour  to  hour. 
The  advantage  of  the  egg- 
shape  is  that  when  the 
volume  of  sewage  is  small, 
there  is  a  greater  depth  of 
liquid  and  less  contact  with 
the  walls  of  the  sewer,  and 
consequently  less  friction, 
than  in  any  other  form. 
The  oval  form  is  also  of 
superior     strength    to    any 

other  form,  as  it  offers  greater  resistance  in  every  direction  to  external 
pressure.  There  is  also  considerable  economy  in  the  construction  of  this 
form.  For  outfall  sewers,  however,  in  which  the  volume  of  sewage  to  be 
■conveyed  is  large  and  fairly  uniform,  Mr.  Baldwin  Latham  advocates  the 
•circular  form,  as  being,  for  these  larger  sizes,  cheaper  to  build  and  stronger 
when  constructed. 

To  render  the  sewers  self-cleansing,  and  to  prevent  deposit  of  sediment  on 
their  floors,  they  must  be  laid  with  a  sufficient  gradient,  and  must  be  con- 
structed of  a  size  suitable  to  the  volume  of  sewage  that  they  will  orduiarily 
be  required  to  carry.  Mr.  Baldwin  Latham  advises  that  sewers  of  from  12 
to  2'1  inches  diameter  should  have  a  gradient  sufficient  to  produce  a  velocity 
of  not  less  than  2^  feet  per  second,  and  in  sewers  of  larger  dimensions  in  no 
■case  should  the  velocity  be  less  than  2  feet  per  second.  A  less  gradient 
is  required  for  large  sewers  than  for  small  sewers  to  produce  the  same  velocity, 
but  the  volume  of  sewage  to  be  conveyed  by  the  larger  sewer  must  far  exceed 
that  to  be  conveyed  by  the  smaller  sewer.  Mr.  liatham  gives  the  following 
example  in  his  work  on  sanitary  engineering  : — A  sewer  10  feet  in  diameter 


Fig.  177. — Section  of  egg-sliaped  brick  sewer. 


832  HYGIENE 

Laving  a  fall  of  2  feet  per  mile  ;  a  sewer  5  feet  in  (liamcter  having  a  fall  of 
4  feet  per  mile  ;  a  sewer  2  feet  in  diameter  having  a  fall  of  10  feet  per 
mile,  and  a  sewer  a  foot  in  diameter,  with  a  fall  of  20  feet  per  mile,  will  all 
have  the  same  velocity  of  How  ;  hut  the  volume  of  sewage  in  the  10-foot  sewer 
must  be  100  times,  in  the  5-foot  sewer  twenty-five  times,  and  in  the  2-foot 
sewer  four  times,  the  volume  of  sewage  in  the  1-foot  sewer. 

In  practice,  however,  it  is  impossible  to  adjust  the  size  of  the  sewers  on 
the  combined  system  to  the  volume  of  sewage  they  arc  ordinarily  intended  to 
carry.  They  must  be  designed  to  receive  a  large  portion  of  the  rain  falling- 
over  the  sewered  area  of  a  town,  as  well  as  the  sewage  proper  from  the  houses. 
In  most  towns  a  large  part  of  the  surface  exposed  to  rainfall  consists  of  im- 
permeable materials — slated  or  tiled  roofs  of  buildings,  paved  yards,  courts, 
and  streets — so  that  the  fallen  rain  runs  rapidly  oft"  the  surface  to  the 
gutters  and  street  gullies  ;  and  it  has  been  estimated  that  on  an  average 
from  one-half  to  three-quarters  of  the  rain  falling  reaches  the  sewers  within 
a  very  few  hours,  and  even  more,  and  in  less  time,  where  there  are  steep 
gradients. 

The  sewers,  then,  have  to  be  constructed  of  such  dimensions  as  to 
admit  a  sudden  influx  of  storm  waters  in  large  amount ;  and  in  ordinary 
times  of  dry  weather  the  volume  of  sewage  conveyed — even  the  maximum 
daily  flow — may  be  insufiicient  to  carry  along  the  suspended  matters,  and 
a  deposit  of  sediment  occurs,  Avliich  has  to  be  removed  by  flushing  or  hand 
labour. 

During  heavy  thunder  showers  in  this  country  an  inch  of  rain  may 
occasionally  fall  in  the  course  of  an  hour  or  less.  But  it  is  not  usual  to 
provide  for  such  heavy  storms,  which  are  certainly  very  exceptional.  The 
usual  provision,  perhaps,  takes  account  of  a  quarter  of  an  inch  of  rain  falling 
in  two  or  three  hours.  If  the  provision  is  insufiicient,  unless  storm-overflows 
have  been  constructed,  the  sewers  in  low-lying  districts  become  overcharged, 
and  cellars  and  basements  in  these  low-lying  houses  are  flooded.  After  a 
period  of  drought  a  sudden  hea^^  storm  effectually  flushes  the  sewers,  the 
accumulated  sewage  deposits  are  swept  away  in  the  rush  of  water,  and  finally 
left  behind  as  a  putrid  mud  on  the  precincts  of  the  flooded  houses.  In  London 
the  intercepting  sewers  were  designed  to  receive  a  quarter  of  an  inch  of  rain 
over  the  whole  sewered  area  of  the  metropolis  in  twenty-four  hours,  and  this 
in  addition  to  the  subsoil  water  ordinarily  finding  its  way  into  the  sewers  ; 
but  numerous  storm-overflows  have  been  constructed,  at  great  cost,  direct 
into  the  Thames  above  London  Bridge,  and  these  relieve  the  overcharged 
sewers  during  heavy  rain,  except  when  their  outfalls  into  the  river  are  tide- 
locked  by  a  high  state  of  the  tide.  At  such  times  low-lying  districts  of  the 
metropolis  are  liable  to  be  flooded,  as  indeed  happened  to  parts  of  the  East 
End  of  London  after  the  tremendous  rainfalls  of  July,  1888.  It  is  certain  also 
that  the  discharge  of  crude  sewage  into  the  Thames  in  the  heart  of  London 
by  these  storm-overflows  is  occasionally  productive  of  considerable  nuisance 
to  the  river-side  inhabitants. 

The  actual  sizes  of  sewers  under  the  combined  system  are  very  various  in 
different  towns.  In  London,  in  many  districts,  pipe  sewers  have  now  been 
laid  in  the  smaller  streets,  the  houses  of  which  they  connect  with  a  brick 
sewer  in  a  main  thoroughfare.  The  brick  sewers  of  the  smaller  streets, 
courts,  and  alleys  vary  in  size  from  3  ft.  by  2  ft.  2  in.  to  4  ft.  by  2  ft.  2  in.  In 
the  larger  streets  they  are  from  4  ft.  G  in.  by  2  ft.  0  in.  to  the  size  of  the  main 
sewers,  which  are  of  considerably  larger  but  varying  dimensions.  The  three 
northern  outfall  sewers  are  each  9  ft.  by  9  ft.,  with  vertical  sides.  The 
southern  outfall  sewer  is  11  ft.  6  in.  in  diameter.     Most  of  the  street  sewers 


THE  DISPOSAL   OF  BE  FUSE  833 

and  all  the  mains  are  large  enough  for  the  sewer  men  to  enter  and  traverse 
when  engaged  in  removing  deposit,  in  repairing  the  sewers,  or  examining 
house  connections. 

As  previously  stated,  the  large  size  of  the  main  sewers  is  necessitated  by 
the  immense  volumes  of  storm  water  they  are  at  times  called  upon  to  receive. 
It  has  been  calculated  that  a  main  sewer  intended  to  receive  all  the  sewage 
of  a  thickly  populated  square  quarter  of  a  mile,  with  a  water  supply  of  twenty 
gallons  per  head  daily,  and  also  the  rainfall  of  the  same  surface,  if  equally 
distributed  over  every  day  of  the  year,  would  only  actually  require  for  these 
purposes  a  sectional  area  of  4  square  feet,  but  that  practically,  in  order  to 
provide  for  sudden  storms,  this  size  would  have  to  be  at  least  doubled.  A 
still  larger  sewer  would  be  necessary  for  the  same  population  if  spread  over 
a  larger  area. 

We  have  seen  that  the  property  possessed  by  the  old  pervious  sewers  of 
draining  the  subsoil  was  a  very  important  one  in  its  bearing  upon  the  public 
health.  Modern  brick  sewers,  being  constructed  of  more  impervious  materials, 
necessarily  act  less  efficiently  as  drains.  But  inasmuch  as  it  is  a  matter  of 
great  difficulty  to  make  brick  sewers  quite  impervious  to  water  it  follows — 
and  such  has  been  proved  by  experience — that  they  do  to  a  certain  extent 
admit  subsoil  water  in  porous  soils,  and  the  sewer  trenches  also  serve  as 
channels  for  the  passage  of  water  alongside  the  sewers  to  escape  at  the  sewer 
outfalls.  It  is  not  therefore  considered  necessary,  as  a  rule,  to  provide  any 
additional  means  of  draining  the  soil  when  brick  sewers  are  in  course  of  con- 
struction. Sometimes,  however,  where  there  is  much  subsoil  water,  a  porous 
pipe  drain  is  laid  under  the  sewer,  to  carry  off  water  in  the  soil  around  it ; 
but  when  this  is  done  there  is  a  possibility  of  settlement  taking  place  from 
sand  being  washed  away  in  the  drain. 

In  the  most  modern  systems  of  sewerage  the  sewers  are  laid  in  straight 
lines,  and  manholes  (fig.  179)  are  built  over  the  sewer  at  the  points  of  change 
of  direction.  The  junctions  of  the  smaller  sewers  with  the  larger  ones  are 
made  at  an  acute  angle,  so  that  the  sewage  enters  the  larger  sewer  from  the 
less  in  the  direction  of  the  flow  of  sewage  in  the  former.  The  points  of 
junction,  wherever  possible,  should  be  above  the  floor  of  the  larger  sewer  to 
prevent  backing  up  of  sewage  in  the  smaller  conduits,  and  consequent 
obstruction  to  the  flow  in  them. 

To  calculate  the  discharge  from  sewers  the  following  formula  is  found 
convenient : — 

Let     V  =  velocity  of  flow  in  feet  per  minute. 
„       D  =  hydraulic  mean  depth. 
,,       F  =  fall  in  feet  per  mile. 
Then  V  =  55  (VD  x  2F). 

If  A  =  sectional  area  or  the  current  of  fluid,  V  x  A  =  discharge  in  cubic 
feet  per  minute. 

The  hydraulic  mean  depth  in  sewers  of  any  section  is  the  sectional  area 
of  the  current  of  fluid  divided  by  the  wetted  perimeter  (that  part  of  the 
circumference  of  the  sewer  wetted  by  the  fluid  flowing  through  it) ;  in  circular 
sewers  it  is  constant  and  equal  to  one-fourth  the  diameter. 

The  Sepaeate  System 

In  this  system  the  house  sewage  is  separated  from  rain  and  surface  waters 
and  conveyed  away  in  pipe  sewers  of  small  diameter.  The  pipes  (fig.  178) 
need  be  only  of  small  size,  for  they  are  not  liable  to  any  sudden  influx  of 

VOL.  I.  3  H 


681 


HYGIENE 


storm  water,  and  the  daily  volume  of  bouse  sewage — even  its  hourly  varia- 
tions— can  be  calculated  with  some  approach  to  accuracy  from  the  water 
supply  and  known  habits  of  the  population.  In  small  towns  the  pipes  usually 
vary  in  size  from  0  in.  to  15  in.  in  diameter,  the  smaller  pipes  receiving  the 
house  sewage  in  the  bye-streets,  and  the  larger  being  collecting  pipes  con- 
ducting the  sewage  to  the  outfall  sewer.  Some  authorities  advise  that  no 
public  street  sewer  should  be  less  than  9  in.  in  diameter,  owing  to  the  risk  of 
smaller  pipes  becoming  obstructed  by  articles  improperly  introduced  into  the 
house  drains ;  but  in  actual  practice  we  believe  it  to  be  very  rare  for  such 
stoppages  to  take  place  in  pipes  of  G  in.  diameter. 

Up  to  18  in.  internal  diameter  sewers  should  certainly  be  circular  in 
section  ;  and  for  these  small  sizes  pipes  of  stoneware,  cement,  or  concrete 
are  preferable  to  brick  sewers.  In  this  country  glazed  stoneware  pipes  are 
most  generally  used  for  the  sewers  of  the  separate  system  ;  but  in  Germany 
cement  and  silicated  concrete  pipes  have  been  extensively  used.  Mr.  Baldwin 
Latham  describes  these  pipes  as  being  less  brittle,  more  capable  of  with- 
standing extremes  of  climate,  and  of  resisting  the  chemical  action  of  the 

sewage  than  stoneware  pipes.  They 
are  also  said  to  improve  materially 
with  age,  and  to  be  unaffected  by  the 
jar  and  vibration  of  heavy  traffic  in 
the  streets  overhead,  which  sometimes 
causes  stoneware  pipes  to  split.  Like 
stoneware,  pipes  of  cement  or  silicated 
concrete  are  impermeable  to  water 
when  properly  jointed. 

As  for  house  drains,  so  stoneware 
pipes  intended  for  sewers  should  be 
laid  on  a  firm  bed  of  hard  ground 
or  cement  concrete  at  gradients  suf- 
ficient to  give  a  velocity  of  flow  of 
2^  or  3  feet  per  second,  according  to 
the  diameter  of  the  pipes.  The  socket 
end  of  the  pipe  should  be  placed  up- 
wards and  the  joint  between  the  spigot 
end  of  the  pipe  above  and  the  socket  of  the  pipe  below  should  be  filled  in  with 
the  best  Portland  cement,  especial  care  being  taken  to  remove  any  cement 
projecting  from  the  interior  of  the  joint  into  the  pipe,  which,  when  hardened, 
would  form  an  obstruction  to  the  flow  of  sewage  through  it.  The  junctions 
between  pipe  sewers  should  be  made  by  means  of  properly  curved  junction 
pipes  ;  and  where  one  or  more  tributary  sewers  join  a  main  sewer,  a  manhole 
(fig.  179)  should  be  built  over  the  point  of  connection,  with  curved  channels 
in  its  floor  for  the  connecting  pipes. 

When  pipe  sewers  are  laid  in  loose  sandy  soils  it  often  happens  that  sub- 
soil water  gets  into  them,  and  issues  from  their  mouths  as  soon  as  they  are 
laid,  in  consequence  of  the  cement,  even  when  covered  with  a  clay  lute,  getting 
washed  into  the  sewers  before  it  has  time  to  set.  If  this  happens  the  sewers 
are  not  impermeable,  and  whilst  subsoil  water  finds  its  way  in,  foul  liquids 
may  percolate  out  into  the  surrounding  soil.  In  these  bad  soils  cast-iron 
pipes  may  be  laid  with  joints  made  with  red  lead,  cement,  and  spun  yarn,  or 
better  with  molten  lead  ;  or  in  the  case  of  stoneware  pipes  Brooke's  subsoil 
drain  and  pipe  rest  may  be  used.  This  subsoil  drain  and  pipe  rest  has  the 
form  of  the  letter  Q  ;  it  is  laid  in  the  bottom  of  the  trench,  like  an  ordinary 
pipe  sewer,  and  jointed  with  clay,  and  has  the  effect  of  lowering  the  subsoil 


Fig.  178. — Pipe  sewer  in  trench. 


THE  DISPOSAL   OF  BE  FUSE 


835 


^ater,  so  that  the  sewer  proper  can  be  laid  upon  the  movable  saddles  or  rests, 
undisturbed  by  water  or  running  sand.  By  these  means  the  cement  joints 
can  be  made  perfect  all  round,  and  have  time  to  set  before  the  trench  is  filled 
up.  True  gradients  are  ensured,  as  the  pipes  can  be  leisurely  laid  ;  and  as  the 
pipes  are  jointed  over  the  middle  of  the  subsoil  drain  a  continuous  foundation 
is  secured.  A  more  perfect  drainage  of  the  subsoil  is  also  found  to  result, 
the  general  level  of  the  water  being  reduced  to  nearly  the  level  of  the  sewer 
invert. 


Fig.  179. — Manhole  and  ventilator. 


The  only  sewers  with  the  separate  system  which  need  be  of  brickwork 
are  the  large  mains  and  outfall  in  good-sized  towns  and  the  outfall  sewer  in 
the  smaller  towns. 

The  pipe  sewers  receive  the  water-closet  sewage  and  waste  waters  of 
houses  only.  The  rain  water  from  the  roofs  and  yards  of  houses  must  be 
conveyed  by  separa,te  pipes  into  surface  channels  at  the  sides  of  the  streets, 
when-,the  gradients  are  sufficient,  or  into  undergroimd  channels  constituting 
a  system  of  drains  quite  distinct  from  the  sewers.  In  many  towns  the  old 
existing  brick  drains  have  been  utihsed  for  the  latter  purpose,  and  they  also 
serve  as  subsoil  drains.  At  convenient  points  the  surface  channels  or  under- 
ground drains  should  discharge  into  the  stream  or  river  which  constitutes 
the  natural  drainage  bed  of  the  locality. 

Where  no  brick  drains  exist  there  is  little  or  no  drainage  of  the  subsoil, 
as  the  pipe  sewers  are  impermeable  to  water.    In  these  cases  agricultural 

3h2 


836  HYGIENE 

tile  drains,  1  to  3  inches  in  diameter  with  open  joints,  should  he  laid  in  the 
same  trench  but  above  the  pipe  sewers — which  are  embedded  in  clay  puddle 
(Baldwin  Latham) — and  surrounded  with  coarse  gravel  to  allow  the  subsoil 
water  to  permeate  into  them ;  at  suitable  points  these  drain  pipes  may  be 
diverted  into  the  watercourses. 

The  advantages  of  the  separate  system  may  be  summed  up  as  follows : — 
(1)  The  whole  volume  of  sewage  to  be  conveyed  away  from  the  town  is  very 
much  less  than  that  to  be  dealt  with  by  the  combined  system.  In  an 
instructive  comparison  of  the  town  of  Slough,  which  is  sewered  on  the 
separate  system,  with  that  of  Romford,  sewered  on  the  combined  system,. 
Mr.  R.  F.  Grantham  has  shown  that  the  average  amount  of  sewage  pumped 
in  a  year  on  to  the  Slough  sewage  farm  was  30,000,000  gallons,  whilst  the 
average  amount  of  a  year's  sewage  received  at  the  Romford  sewage  farm  was 
over  100,000,000  gallons,  Slough  having  a  population  of  5,200,  with  a  water 
supply  of  ten  gallons  per  head  daily,  and  Romford  a  population  of  6,300,  with 
the  same  amount  of  water  supply. 

(2)  The  daily  and  seasonal  fluctuations  m  the  volumes  of  sewage 
deUvered  urfder  the  separate  system  are  small,  and  the  total  quantities 
to  be  dealt  with  can  be  approximately  calculated  from  the  population 
and  water  supply,  these  being  points  of  the  greatest  practical  importance 
where  the  sewage  has  to  be  pumped  at  the  outfall  or  purified  before  being 
discharged.  The  daily  and  weekly  fluctuations  under  the  combined  system 
may  be  enormous  owing  to  the  entry  of  rain  and  subsoil  water  into  the  sewers. 
Thus  at  Romford,  during  a  period  of  three  years,  the  largest  amount  of 
sewage  received  in  the  course  of  a  week  at  the  sewage  farm  was  3,G62,000 
gallons,  and  the  smallest  amount  representing  the  dry  weather  flow  only 
1,321,000  gallons — equal  to  about  one-third  of  the  greatest. 

(3)  On  the  other  hand,  on  the  separate  system,  the  sewage  of  every  twenty- 
four  hours  is  fairly  uniform  in  composition,  because  it  is  protected  from  dilution 
wdth  storm  waters,  and  its  purification  and  utilisation  are  midertaken  with 
much  less  difficulty  than  ui  the  case  of  sewage  varying  in  strength  accord- 
ing to  the  amount  of  rain  and  subsoil  water  mixed  with  it. 

(4)  The  sewers,  too,  being  of  small  size  and  having  perfectly  smooth 
walls,  are  more  often  running  full,  and  are  therefore  better  flushed,  with  less- 
tendency  to  deposit  sediment  resulting  in  the  formation  of  foul  gases,  than 
is  the  case  with  the  large  brick  sewers,  to  whose  walls  foul  matters  so  readily 
adhere. 

(5)  Lastly,  the  cost  of  the  system  is  very  much  less  than  that  of  the 
combined  system.  Pipe  sewers  are  more  quickly  laid  than  brick  sewers  can 
be  built ;  they  require  a  much  smaller  amount  of  excavation  than  brick 
sewers,  and  they  can  be  made  with  very  various  curves  to  suit  different 
positions. 

The  disadvantages  of  the  separate  system  are,  that  every  house  must 
be  provided  with  tw^o  drains,  or  two  sets  of  pipes — one  for  sewage  and  the 
other  for  rain  water.  This  means  a  somewhat  heavy  initial  outlay  on  the 
part  of  houseowners,  and  it  occasionally  gives  rise  to  mistakes  on  the  part 
of  builders,  who  connect  the  pipes  with  the  wrong  system.  The  surface 
water  from  yards  and  streets  is  also  sometimes  foul,  especially  when  a  storm 
succeeds  a  period  of  drought,  and  this  foul  water  may  conceivably  cause  a 
nuisance  in  the  stream  into  which  it  is  discharged.  At  Slough,  however,  no 
complaint  has  ever  been  made  about  the  surface-water  drain,  which  discharges 
into  a  ditch  by  the  side  of  a  public  road  within  the  statutory  three  miles 
distance  from  the  river  Thames,  and  therefore  within  the  jurisdiction  of  the 
Thames   Conservancy.    It  has  been  recommended  that  the  surface  water 


THE  DISPOSAL   OF  BEFUSE  837 

-from  the  back  yards  of  houses  should  be  discharged  into  the  sewers,  instead 
of  into  the  surface  channels  or  subsoil  drains,  as  these  waters  are  often  of  a 
somewhat  polluting  nature.  But  it  would  probably  be  better  for  the  local 
authorities  to  enforce  proper  scavenging  and  cleansing  of  the  yards  and 
streets  than  to  introduce  storm  waters  into  pipes  of  size  possibly  inadequate 
for  their  reception. 

Numerous  towns  in  this  country  are  now  provided  witli  pipe  sewers,  and 
the  system  is  likely  to  be  much  more  largely  adopted  in  all  eases  where 
circumstances  are  favourable  to  its  execution.  In  America,  the  city  of 
Memphis  has  been  sewered  on  the  separate  system,  the  plans  of  the  works 
being  designed  and  carried  into  execution  under  the  direction  of  Colonel 
Waring.  A  very  complete  and  interesting  account  of  the  system  and  its 
working  at  Memphis  will  be  found  in  the  Second  Annual  Eeport  of  the 
State  Board  of  Health,  New  York,  1882.  Pullman,  near  Chicago,  is  also 
sewered  on  the  same  system,  and  numerous  other  towns  in  the  States  propose 
to  adopt  similar  works. 

Flushing  and  Inspection  op  Sbwees 

In  the  old  badly  constructed  brick  sewers,  without  sufficient  incline,  large 
deposits  of  semi-solid  filth  took  place,  which  were  removed  by  hand  labour 
at  great  expense.     In  some  cases  the  deposit  was  removed  through  manhole 

■  entrances  to  the  sewers,  but  in  others  where  it  was  3  or  even  4  ft.  thick,  and 
had  stopped  up  the  sewer,  not  only  had  the  street  to  be  broken  up,  but  the 
arch  of  the  sewer  was  also  broken  into,  and  the  foul  mud  raised  to  the 
surface  and  carted  away,  the  whole  process  causing  a  very  great  nuisance  to 
the  neighbourhood.  The  late  Sir  Joseph  Bazalgette  in  his  work  on  the 
■'Main  Drainage  of  London  '  has  stated  that  the  cost  of  removing  deposits 
from  the  tide-locked  and  stagnant  sewers  in  London  formerly  amounted  to 
about  3O,000Z.  per  annum. 

It  soon,  however,  came  to  he  understood  that  periodical  flushing  of  the 
sewers  was  able  to  accomplish  this  work  of  carrying  away  sediment  in  a  far 
more  efficient  and  economical  manner  than  removal  by  hand  labour.  By 
heading  up  the  sewage  in  a  certain  spot,  by  means  of  sluices  or  flushing 
gates  made  to  fit  the  greater  part  of  the  sectional  area  of  the  sewer,  a  force 
sufficient  to  effectually  flush  and  cleanse  the  sewer  below  for  a  considerable 

■  distance  can  be  generated  on  raising  or  liberating  the  gate. 

These  flushing  gates  can  be  fixed  at  the  sites  of  manholes,  and  can  then 
be  manipulated  by  the  sewer  men,  or  self-acting  gates  can  be  used  for  the 
same  purpose.  In  this  form  the  gate  is  fixed  in  the  sewer  by  hinges 
attached  below  its  centre.  The  pressure  of  the  sewage  on  that  portion  of 
the  gate  which  is  below  the  hinge  fixes  it  in  position,  and  the  sewage  rises 
until  it  reaches  the  upper  portion  of  the  gate.  This  presents  a  larger  surface 
to  the  dammed- up  sewage  than  the  lower  portion  of  the  gate  below  the 
hinges,  so  that  a  point  is  at  length  reached  when  the  gate  tilts  forwards, 
assuming  a  horizontal  position,  and  the  sewage  escapes  with  a  velocity  pro- 
portional to  its  head. 

These  gates  are  of  course  inapplicable  to  the  upper  or  dead  ends  of  brick 
sewers.  Perhaps  the  best  method  of  flushing  these  and  the  smaller  tributary 
sewers  is  to  discharge  the  contents  of  a  street  watering  cart  suddenly  into  a 
manhole  or  other  opening  into  the  sewer. 

Sewers  are  most  in  need  of  flushing  during  the  summer  season  and  pro- 
longed periods  of  dry  weather.     At  these  times,  unless  artificial  flushing  is 


838  HYGIENE 

resorted  to,  tlie  amount  of  water  flowing  throngli  the  sewers  is  insufiicient  to 
prevent  the  deposit  of  sediment.  But  the  flushing  should  he  periodical  in 
the  older  hrick  sewers  all  the  year  roimd,  for,  although  heavy  rainfall  is  very 
efl'ectual  for  flushing  purposes,  it  cannot  he  depended  upon  in  this  climate  to 
occur  at  properly  recurring  intervals,  and  it  introduces,  hesides,  a  quantity  of 
sand  and  grit  from  the  surfaces  of  the  roads  which  tends  to  settle  in  de- 
pressed portions  of  the  floors  of  the  sewers,  and  to  form  the  nidus  for  further 
deposits  of  sediment. 

It  is  certainly  advisable  that  arrangements  should  be  made  for  flushing 
the  pipe  sewers  of  the  separate  system,  inasmuch  as  they  do  not  experience 
the  cleansing  eflect  of  storm  waters,  in  all  cases  except  where  the  gradients 
are  very  good  and  the  water  allotted  for  closet-flushing  purposes  is  ample.. 
Perhaps  the  best  method  is  that  introduced  by  Colonel  Waring  in  the  case 
of  the  pipe  sewers  at  Memphis.  At  the  dead  end  of  every  branch  sewer  is 
placed  an  automatic  siphon  flush  tank  with  a  capacity  of  112  gallons.  The 
tank  consists  of  a  brick  chamber,  built  on  a  concrete  bottom,  set  below  the 
level  of  the  street  and  covered  with  a  perforated  lid  ;  in  the  centre  of  the  tank 
is  an  annular  siphon  (fig.  185,  p.  888)  which  discharges  into  a  box  underneath 
it,  and  thence  into  the  sewer.  The  tanks  are  filled  from  the  city  water 
supply,  and  discharge  their  contents  with  the  most  perfect  regularity.  The 
rush  of  water  from  them  is  distinctly  felt  at  a  distance  varying  from  400  to- 
900  ft.,  keeping  the  pipes  perfectly  clean.  No  tendency  to  freeze  has  been 
noticed  in  the  tanks,  although  the  temperature  of  the  air  has  been  as  low  as 
4°  F.  In  all,  there  are  125  of  these  flush  tanks  at  work  in  Memphis  to  flush 
twenty  miles  of  sewers.  A  slight  deposit  of  silt  has  at  times  occurred  in  some 
of  the  mains,  but  this  has  never  been  more  than  1  or  Ih  mches  in  depth. 

Means  of  access  must  be  provided  for  brick  sewers — for  their  examination, 
for  the  execution  of  necessary  repairs,  and  for  iheir  cleansing.  For  this 
purpose  manhole  shafts  (fig.  179)  are  sunk  from  the  surface  of  the  road  to  the 
sewer  by  which  the  scavengers  can  descend.  They  are  constructed  of  brick- 
work and  provided  with  a  locked  iron  door  at  the  street  level.  In  streets 
with  much  trafiic  the  shaft  is  sunk  from  the  footway  perpendicularly  for 
a  sufiicient  distance  and  then  carried  down  by  means  of  steps  to  the  side  of 
the  sewer.  In  unfrequented  thoroughfares  the  manholes  may  be  sunk  from 
the  roadway  direct  to  the  crown  of  the  sewer  or  immediately  at  its  side. 
The  side  entrances  are  not  so  cleanly  as  those  opening  into  the  crown  of  the 
sewer,  as  in  times  of  heavy  rain  the  sewage  may  leave  detritus  on  the  steps 
of  the  passage,  which  subsequently  decomposes  and  gives  rise  to  offensive ■ 
effluvia. 

The  manholes  have  also  other  uses  ;  they  serve  as  points  of  junction 
between  tributary  sewers  and  the  main  sewers,  and  they  are  the  points  at 
which  flushing  gates  and  ventilators  may  most  advantageouly  be  fixed. 

In  the  pipe  system  of  sewerage  manholes  should  be  constructed  on  the 
mains  at  convenient  points,  such  as  where  a  change  of  direction  occurs 
(fig.  179),  At  Memphis  there  is  a  manhole  at  a  distance  of  every  500  ft.  on 
the  mains.  On  the  branch  sewers  T-pieces  should  be  inserted  at  intervals, 
with  a  lid  on  the  top  of  the  upright  stem  at  the  street  level,  which  can 
readily  be  removed,  and  a  cleaning  tool  introduced  to  clear  away  the  obstruc- 
tions which  are  occasionally  produced  by  the  introduction  of  improper 
articles  into  the  house  drains.  At  Memphis  several  2-foot  carpenters'  rules, 
folded  to  G  inches,  which  had  passed  through  the  4-inch  traps  on  the  house- 
drains,  have  been  removed  from  the  G-inch  pipe  sewers  after  causing  an 
obstruction  to  the  flow  of  sewage  through  them. 


THE  DISPOSAL   OF  BE  FUSE  839 

Ventilation  op  Seweks 

Considerations  arising  from  the  facts  elicited  by  modern  research  into  the 
causation  and  propagation  of  infectious  diseases  have  imparted  an  importance 
and  significance  to  the  subject  of  sewer  ventilation  which  was  absent  in 
times  but  recently  passed.  To  know  that  the  infective  agents  of  such  diseases 
as  cholera,  typhoid  fever,  many  cases  of  diarrhoja,  and  probably  other 
diseases,  are  passed  out  of  the  body  in  the  excretions  of  the  patients  suffering 
from  them,  that  they  probably  have  the  power  of  self-multiplication  outside 
the  body  in  sewers  and  sewer  deposits,  and  can  infect  the  air  in  contact  with 
them,  is  to  understand  the  importance  which  sewer  ventilation  has  on  the 
public  health,  and  to  impress  the  necessity  for  the  closest  attention  to  this 
subject  on  the  part  of  those  who  are  entrusted  with  local  sanitary  adminis- 
tration. 

In  the  first  place,  we  see  that  town  sewers  are  underground  channels, 
which  place  houses  both  near  and  remote  from  one  another  in  more  or  less 
direct  aerial  connection  in  all  cases  except  where  the  house  drains  are 
disconnected  from  the  sewer  by  a  water  trap  and  an  opening  to  the  external 
air  on  the  house  side  of  the  trap.  Between  houses  where  this  form  of  dis- 
connection is  not  practised,  not  only  is  there  the  aerial  connection,  but  rats 
and  other  vermin  may  be  the  means  of  carrying  infected  filth  from  a  fever- 
stricken  house  to  a  healthy  one.  This  latter  mode  of  conveying  contagion 
has,  however,  been  more  fully  treated  of  in  the  chapter  on  house  drainage, 
and  does  not  require  consideration  here.  It  is  sufficient  for  us  here  to  know 
that  the  poisonous  agents  of  disease  excreted  in  one  house  may  be  wafted  in 
the  air  of  the  sewers  into  the  drainage  pipes  of  another  house  in  its  neigh- 
bourhood, or  even  remote  from  it.  To  counteract  this  mode  of  propagation, 
of  disease,  two  precautions  are  essential.  The  first  is  to  prevent  by  means  of 
water-traps  and  a  proper  system  of  house-drain  ventilation  any  entrance 
of  drain  or  sewer  air  into  houses ;  the  second  is  the  adoption  by  local 
authorities  of  some  means  whereby  an  abundance  of  fresh  air  can  be  mtro- 
duced  into  the  sewers,  and  the  mixed  air  and  gases  can  escape  from  the 
sewers  at  points  as  remote  as  possible  from  inhabited  dwellings.  As  in 
house  drains,  so  in  sewers,  a  constant  current  of  fresh  air  should  be  flowino- 
through  them  to  dilute  the  offensive  gases  and  render  less  dangerous  the 
disease  poisons  which  may  possibly  be  present,  and  this  current  very  effec- 
tually aids  the  escape  of  the  sewer  air  at  the  proper  points  of  exit. 

It  is  now  generally  believed  that  the  bowel  discharges  in  cases  of  typhoid 
fever  and  allied  diseases  may  impart  their  infective  qualities  to  large  volumes 
of  sewage,  and  to  the  deposits  and  slime  which  are  so  frequently  found  on 
the  floors  and  walls  of  sewers.  The  microbes  of  such  diseases  find  a  suit- 
able soil  for  growth  and  multiplication  in  sewage  and  sewer  deposits,  which, 
it  must  be  remembered,  are  always  considerably  warmer  than  the  outer 
atmosphere  during  the  winter  months,  and  contain  organic  matters  of  both 
animal  and  vegetable  origin,  phosphates,  nitrates,  and  ammonia,  all  affording 
food  for  the  growth  of  micro-organisms.  There  is  plenty  of  evidence  to 
show  that  the  percolation  of  infected  sewage  out  of  sewers  into  wells  and 
water  mains  has  produced  epidemic  outbursts  of  fever ;  and  there  can  be 
but  little  doubt  that  the  sewer  air  in  contact  with  such  infected  materials 
also  becomes  imbued  with  specifically  contagious  properties.  For  enteric 
fever  has  undoubtedly  been  caused  by  inhalation  of  sewer  air,  no  other  means 
being  ascertainable  by  which  the  infected  persons  could  have  been  brought 
into  contact  with  contagion ;  and  there  are  the  records  of  specific  contami- 
nation of  drinking  water  in  cisterns  and  mains  by  such  air. 


810  HYGIENE 

Amongst  other  diseases  of  which  proof  has  been  adduced  that  they  are 
occasionally  the  result  of  sewer-air  pollution  may  be  mentioned  a  severe 
form  of  acute  tonsillitis  (sewer-air  throat),  diphtheria,  and  the  hospital 
fevers — surgical  fever,  erysipelas,  pyaemia,  septici^mia,  and  puerperal  fever. 
Years  ago  these  diseases  were  very  constantly  present  in  the  wards  of 
general  and  lying-in  hospitals  ;  but  since  measures  have  been  taken  to 
improve  the  drainage  of  these  institutions  and  prevent  any  possibility  of 
foul  air  gaining  access  to  the  wards,  such  diseases  have  greatly  diminished, 
or  even  totally  disappeared. 

As  regards  chemical  composition,  sewer  air  varies  very  widely.  In 
modern  well-ventilated  sewers  the  air  is  by  no  means  foul.  Samples  collected 
by  Dr.  W.  J.  Kussell  from  the  metropolitan  sewers  in  the  Paddington  district 
during  the  month  of  August,  1869,  were  found  to  contain  0-51  volume  of 
carbonic  acid,  20*7  of  oxygen,  and  78'79  of  nitrogen  in  100  volumes.  In 
so  far  as  these  constituents  are  concerned,  the  impurity  is  not  great,  and  in 
no  way  accounts  for  the  mjurious  properties  of  sewer  air. 

In  the  old-fashioned  brick  sewers,  where  sediment  collects,  the  gaseous 
impurity  is  often  excessive.  Brick  conduits  with  flat  bottoms  (fig.  176), 
circular  or  oval  sewers  in  which  a  portion  of  the  invert  has  sunk  below  its 
proper  level,  and  sewers  which  are  too  large  for  the  volume  of  sewage  they 
ordinarily  convey,  are  all  liable  to  deposits  of  sediment  on  their  floors  or 
sides,  which  can  only  be  removed  by  artificial  flushing.  The  bacterial  agents 
of  putrefaction  present  in  all  sewers  attack  the  sediment,  and  cause  a  fer- 
mentation productive  of  the  evolution  of  such  foul  gases  as  sulphuretted 
hydrogen,  ammonium  sulphide,  and  carbon  disulphide.  Some  of  the  other 
foetid  gases  given  off  during  the  putrefactive  process  are  highly  complex 
bodies,  probably  carbo-ammoniacal  and  allied  in  chemical  constitution  to 
the  compound  ammonias — methylamine  and  ethylamine.  These  have  a 
highly  offensive  odour.  Organic  vapours  of  unknown  constitution  are  also 
evolved,  and  amongst  these  may  occasionally  be  found  traces  of  the  animal 
alkaloidal  substances— ptomaines  and  leucomaines — which  are  contained  in 
the  faecal  and  urinary  excretions  of  the  animal  body,  and  exert  a  directly 
poisonous  action  on  the  system.  Free  ammonia  is  also  given  off  to  a  slight 
degree  by  putrefying  sewage,  and  is  derived  from  fermentation  of  the  urea 
of  urine — a  molecule  of  urea  takmg  up  two  molecules  of  water  to  become 
carbonate  of  ammonium.  Of  innocuous  gases  given  off,  the  chief  are  carbonic 
acid,  nitrogen,  and  carburetted  hydrogen. 

Of  late  much  attention  has  been  directed  to  the  organised  constituents 
of  sewer  air — to  the  microbes  (bacteria  and  moulds  with  their  spores).  By 
the  method  of  plate  cultivation  of  the  microbial  colonies  on  solid  nutrient 
media  it  is  now  possible  to  estimate  the  number  of  micro-organisms  or  their 
spores  present  in  a  measured  volume  of  sewer  air,  which  are  capable  of 
growing  in  these  media  at  temperatures  below  that  at  which  the  solid  medium 
liquefies.  Observations  made  by  this  method  in  this  country  tend  to  show 
that  sewer  air,  taken  from  sewers  in  which  fermentative  processes  are  in 
abeyance,  is  remarkably  free  from  all  such  microbes.  The  microbes  remain 
in  the  sewage,  and  are  not  given  off  to  the  air  in  contact  with  it,  or  if  they 
are,  there  is  reason  to  believe  that  they  quickly  adhere  to  the  moist  internal 
walls  of  the  sewer,  and  are  thus  prevented  from  floating  far.  That  such  is 
the  explanation  is  rendered  more  certain  by  what  is  already  known  of  the 
presence  of  microbes  in  the  outer  atmosphere,  for  during  dry  or  dusty 
weather  they  are  found  in  far  larger  numbers  than  during  or  after  rainfall. 
These  experiments  have  been  made  on  the  air  of  sewers,  in  which  the 


THE  DISPOSAL   OF  BEFUSE  841 

sewage  is  carried  away  in  a  fairly  fresh  and  undecomposed  condition.  But 
we  believe  that  no  extended  observations  have  yet  been  made  on  the  air  of 
those  sewers  where  accumulations  of  putrefying  sediment  are  to  be  found. 
In  such  cases  we  are  inclined  to  believe  that  the  sewer  air  contains  floating 
in  it  an  excessive  number  of  microbes  and  spores.  In  the  first  place,  there 
is  the  almost  universal  domestic  experience  that  meat,  milk,  and  other 
organic  substances  rapidly  taint  and  putrefy  when  exposed  to  drain  or  sewer 
emanations,  and  this  points  strongly  to  the  presence  of  the  bacterial  agents 
of  putrefaction  in  such  air  ;  and,  secondly,  it  was  demonstrated,  as  long  ago 
as  1871  by  Professor  Frankland,  that,  although  liquids  flowing  smoothly  in 
channels  give  off  no  solid  particles  to  the  air,  and  that  even  considerable 
agitation  resulting  in  frothing  may  not  cause  any  perceptible  increase  of  the 
solid  particles  in  the  superincumbent  air,  yet  the  bursting  of  bubbles  of  gas 
in  a  liquid  had  a  marked  effect  in  disseminating  solid  particles.  The  burst- 
ing of  bubbles  of  gas  on  the  surface  of  a  liquid  is  an  invariable  accompani- 
ment of  the  fermentative  processes  which  take  place  in  stagnant  sewage  and 
sewage  deposits,  so  that  there  can  now  be  little  doubt  but  that  the  air  in 
contact  with  putrefying  sewage  is  loaded  with  micro-organisms  of  different 
kinds.  Frankland's  conclusions,  too,  have  been  practically  confirmed  by  the 
•experiments  of  other  and  later  observers. 

And,  after  all,  it  is  not  so  much  a  question  of  the  quantity  of  bacterial 
organisms  present  in  sewer  air  as  of  the  quality  of  those  that  do  exist, 
whether  large  or  small  in  number.  The  fallacy  of  reasoning  that,  because 
sewer  air  under  ordinary  conditions  contains  but  few  demonstrable  organisms 
it  must  ipso  facto  be  innocuous,  is  sufficiently  obvious  to  require  no  refutation. 
Too  little  is  known  at  present  about  the  microbes  present  in  sewers  to 
warrant  dogmatic  assertions  of  any  kind,  but  it  is  believed  that  the  large 
majority  are  harmless  or  at  least  non-pathogenic.  Others  there  may  be,  pre- 
sent at  times  only,  and  then,  perhaps,  not  in  company  with  a  crowd  of 
Jaarmless  species,  which  are  productive  of  those  varieties  of  illness  in  the 
human  subject  that  are  known  to  result  from  sewer-air  poisoning.  The 
history  of  sanitation  in  this  country,  too,  tends  conclusively  to  show  that 
improvements  in  sewerage  and  house  drainage,  whereby  sewer  air  is  excluded 
from  houses  and  dispersed  harmlessly  in  the  external  atmosphere,  have 
had  a  most  beneficial  effect  upon  the  public  health  in  the  reduction  of  the 
prevalence  and  mortality  from  typhoid  fever  and  the  other  filth  diseases. 

The  injurious  effects  attributable  to  the  inhalation  of  sewer  air  may  for 
•convenience  be  divided  into  those  produced  by  the  foul  inorganic  gases,  and 
those  resulting  from  the  organic  vapours  or  the  organised  constituents  of  such 
air.  Under  the  first  head  must  probably  be  classed  those  cases  of  complete 
or  partial  asphyxia  which  formerly  occurred  amongst  the  Paris  scavengers 
when  engaged  in  removing  deposit  from  choked  sewers,  or  in  emptying  and 
cleansing  cesspools  and  privies.  These  asphyxial  symptoms  {le  plomh)  were 
either  caused  by  excessive  disengagement  of  sulphuretted  hydrogen  gas, 
when  the  contents  of  the  sewers  or  cesspools  were  stirred  up,  or  were  due  to 
the  very  low  proportionate  volume  of  oxygen  existing  in  the  air,  or  to  both 
•of  these  causes  combined.  Thus  Parent  Duchatelet  found  the  ah'  of  a  choked 
sewer  in  Paris  to  contam  nearly  3  per  cent,  of  sulphuretted  hydrogen,  and 
only  13*8  per  cent,  of  oxygen. 

Cases  of  acute  mephitic  poisoning  have  been  recorded  amongst  scavengers 
employed  in  cleansing  foul  drains  and  sewers,  the  symptoms  being  sudden 
and  violent  vomiting,  purging,  and  headache,  followed  shortly  by  acute  pro- 
;stration,  sometimes  ending  fatally.     These  symptoms  are  probalaly  as  much 


842  HYGIENE 

due  to  inhalation  of  foul  organic  vapours  as  to  the  inorganic  compounds  of 
sulphur  or  ammonia. 

At  the  present  day,  owing  to  the  improved  construction  of  sewers  and 
their  better  ventilation,  such  cases  of  asphyxia  or  acute  poisoning  amongst 
the  sewer  men  are  very  rare.  As  a  rule,  these  men  appear  to  enjoy  very 
fair  health,  no  doubt  because  their  work  is  now  conducted  in  a  relatively  pure 
atmosphere.  But  it  must  be  remembered  that  they  are  picked  men  in  the 
prime  of  life,  for  only  those  continue  at  the  w'ork  who  find  no  injury  to  health 
arising  from  it ;  probably  many  men  give  it  up  after  a  short  trial,  as  being 
unsuited  to  tlieir  constitutions.  It  has  also  been  stated  that  sewer  men,  as  a 
class,  suffer  somewhat  from  ophthalmia  and  headaches,  and  that  the  occupa- 
tion tends  greatly  to  aggravate  venereal  disease  (Parent  Duchatelet).  It 
seems  fair  to  assume  now,  in  the  light  of  our  present  knowledge,  that  the 
men  engaged  in  this  occupation  undergo  a  species  of  preventive  inoculation 
or  acclimatisation,  so  to  speak,  to  the  influences  to  which  they  are  exposed. 
The  long-continued  inhalation  or  ingestion  of  a  germ-tainted  air  may  be 
considered  as  conferring  immunity  upon  the  individual  from  filth  diseases 
which  would  readily  attack  one  whose  system  had  not  been  exposed  to  the 
acclimatising  process. 

The  contamination  of  the  air  of  houses  with  sewer  or  drain  emanations 
appears  to  be  productive  in  many  instances  of  loss  of  health  amongst  the 
occupants,  more  especially  in  those  cases  where  the  escape  of  sewer  air  is 
continued  for  long  periods.  The  dose  of  the  poisonous  atmosphere  may  not 
be  sufficiently  great  at  any  one  time  to  cause  those  acute  and  dangerous 
illnesses  before  mentioned,  but  a  condition  of  ill-health  is  engendered, 
especially  in  children,  shown  in  various  ways,  as  by  loss  of  appetite,  pro- 
stration, diarrhoea,  antemia,  headache,  vomiting,  sore  throat,  and  fever. 
One  or  more  of  these  symptoms  predominate  over  the  rest,  according  to  the 
season  of  the  year  and  the  idiosyncrasies  of  the  individual.  Dr.  George 
Johnson  has  described  cases  of  albuminuria  and  destructive  kidney  disease 
as  being  the  result  of  long-continued  sewer-air  inhalation.  Whether  ren- 
dered seriously  ill  or  not,  a  condition  of  depressed  vitality  is  certainly  a 
marked  characteristic  of  the  inmates  of  a  badly  drained  house. 

It  is  now  generally  believed  that  these  symptoms  of  illness  are  due  to  the 
entrance  mto  the  body  of  the  organic  matters  present  in  the  sewer  air ;  and 
modern  views  regard  the  micro-organisms,  which  constitute  a  certain  pro- 
portion of  these  organic  matters,  as  being  the  poisoning  agents  rather  than 
the  gases  and  vapours,  however  complex  in  their  chemical  constitution. 
Whether  these  microbes  should  be  classed  as  pathogenic  organisms,  or 
whether  they  are  to  be  regarded  as  the  ordinary  bacteria  of  putrefaction  and 
fermentation,  which  on  entrance  into  the  body  pervert  the  healthy  action  of 
the  tissues,  causing  diseased  processes,  is  a  problem  the  solution  of  which  is 
not  yet  reached. 

It  now  becomes  necessary  to  inquire  into  the  causes  which  produce 
movements  of  air  in  the  sewers,  for  only  upon  a  proper  understanding  of 
this  subject  can  any  system  of  efficient  sewer  ventilation  be  founded.  The 
most  important  of  these  causes  are  :  (1)  a  strong  and  rapid  stream  of  sewage 
tends  to  create  a  current  of  air  in  the  sewer  in  the  same  direction  as  the 
flow  of  sewage,  and  of  proportionate  velocity.  Under  such  circumstances 
many  of  the  street  openings  into  the  sewers  become  inlets  for  fresh  air, 
which  travels  with  the  current  of  sewage  and  finally  escapes  at  the  sewer 
outfall.  (2)  As  the  volume  of  sewage  increases  air  is  expelled  from  the 
sewer,  to  again  find  its  way  in  when  the  volume  of  sewage  diminishes.  As 
a  rule,  the  quantity  of  sewage  passing  down  a  sewer  steadily  increases  from 


TEE  DISPOSAL   OF  BE  FUSE  843- 

the  early  morning  hours  up  to  noon,  and  in  the  afternoon  as  gradually 
diminishes,  until  at  night  in  brick  sewers  little  but  subsoil  water  is  being 
conveyed.     It  follows,  then,  that  in  the  morning  air  is  being  slowly  expelled 
from  the  sewers,  whilst  for  the  rest  of  the  day  the  reverse  action  takes  place.. 
The  sudden  influx  of  a  large  quantity  of  storm  water  into  a  sewer  causes  a . 
very  appreciable  expulsion  of  air ;  but  this  is,  to  a  certain  extent,  counter- 
balanced by  the  aspirating  effect  of  the  current  of  air  in  the  direction  of  the 
flow  of  sewage.     The  rising  of  the  tide  in  an  outfall  sewer  unprotected  by  a 
tidal  valve  also  causes  expulsion  of  air,  but  the  displacement  is  so  gradual 
as  to  be  almost  inappreciable,  owing  to  the  slowness  with  which  the  water 
rises  and  the  innumerable  channels  permeable  to  air  by  which  the  interior 
of  a  brick  sewer  communicates  with  the  exterior.     (3)  During  the  colder 
months  of  the  year  the  temperature  within  a  sewer  is,  owing  to  the  warmth 
of  the  sewage,  considerably  higher  (averaging  about  7°  F.)  than  that  of  the 
outer  atmosphere  ;  consequently  the  warmer  sewer  air  tends  to  rise  and  be 
replaced  by  the  colder  air  from  above.     In  the  summer  months  the  day 
temperature  of  the  sewer  is  often  below  that  of  the  external  air,  and  the 
interchange  between  the  sewer  air  and  the  outer  atmosphere  is  reduced  to  a 
minimum.     In  the  spring  and  autumn  months  the  temperatures  inside  and 
outside  tend  to  approximate.     (4)  The  discharge  of  large  volumes  of  hot 
liquids  from  houses  and  factories,  and  the  practice  of  blowing  off  steam 
from  boilers  into  the  sewers,  causes  heating  and  expansion  of  the  sewer  air 
and  its  rapid  expulsion  through  the  nearest  sewer  openings.     This  more 
especially  follows  the  blowing  off  of  steam,  and  sometimes,  when  the  sewers 
are  insufficiently  ventilated,  results  in  the  forcing  of  the  traps  on  house 
drains  and  pipes,  and  the  escape  of  the  foul  air  into  the  interiors  of  houses- 
There  is  also  the  objection  to  the  introduction  of  hot  liquids  or  steam  into 
sewers  that  the  decomposition  of  the  sewage  is  accelerated  by  the  high 
temperature  to  which  it  is  raised,  and  that,  in  consequence  of  the  saturated 
condition  of  the  air  and  its  high  temperature,  the  sewer  cannot  be  entered 
until  it  has  been  opened  to  the  air  for  some  time  by  means  of  the  manholes,, 
and  thus  a  difficulty  is  placed  in  the  way  of  frequent  inspection.     (5)  Sudden 
changes  of  barometrical  pressure  and  of  external  temperature  cause  corre- 
sponding variations  in  pressure  within  the  sewer,  resulting  in  the  passage  of 
air,  as  the  case  may  be,  into  or  out  of  the  sewer. 

If  the  sewers  have  no  ventilation  openings,  or  if,  for  any  reason,  these 
have  become  choked  or  stopped  up,  the  air  within,  from  the  causes  above 
mentioned,  will  find  its  way  out  through  defective  joints  on  house  drains  or 
soil  pipes,  through  bell-traps  in  floors  or  on  waste  pipes,  into  the  interiors  of 
houses  in  all  those  eases  where  there  is  no  disconnection  trap  on  the  house 
drain ;  and  these  escapes  of  sewer  air  tend  to  become  aggravated  by  the 
aspirating  effect  of  fires  and  the  warmth  of  inhabited  houses  on  the  colder 
air  contained  in  the  drain  and  soil  pipes.  In  houses  of  this  class  the  rain- 
water pipes  from  the  roof,  being  directly  connected  with  the  house  drain  and 
sewer,  without  the  intervention  of  a  trap,  may  act  as  sewer  ventilators. 
But  such  a  plan  is  a  dangerous  one,  as  these  pipes  are  usually  very  loosely 
jointed,  and  the  air  rising  from  the  sewer  will  escape  through  every  such 
joint,  possibly  into  bedrooms  ;  and  in  many  cases  the  open  head  of  the  pipe 
is  just  beneath  a  dormer  or  attic  window.  During  heavy  rain,  too,  the  rush 
of  water  down  these  pipes  will  force  the  foul  air  into  the  ulterior  of  the 
house  through  trapped  or  untrapped  openings. 

The  ventilation  of  sewers  by  means  of  the  soil-pipe  ventilators  of  houses 
is  equally  objectionable,  except  where  the  sewers  are  stoneware  pipes  laid 
between  the  backs  of  two  rows  of  houses,  for  then  the  drains  will  not  pass 


•844  HYGIENE 

under  the  basements  of  houses,  and  the  entry  of  sewer  air  into  the  house 
may  be  prevented  by  trapping  and  disconnecting  all  waste  and  overflow 
pipes,  and  substituting  siphon  gullies  for  bell-traps.  But  where  houses 
drain  into  sewers  laid  in  the  front  road,  the  drain  must  pass  under  the 
house,  and  with  this  method  of  sewer  ventilation  there  would  be  constant 
risk  of  the  escape  of  sewer  air  through  defective  joints  into  the  interior  of 
the  house.  There  is  also  another  objection  to  this  method,  which  applies  to 
the  case  of  sewers  which  receive  rainfall.  During  or  after  heavy  rain,  when 
ventilation  is  most  required  for  alibrding  a  safe  exit  for  suddenly  displaced 
sewer  air,  house  drains,  or  any  part  of  them,  are  often  useless  for  this  purpose, 
as  their  openings  into  the  sewer  may  be  sealed  by  the  height  at  which  the 
mixed  sewage  and  storm  water  is  flowing.  This  is  also  a  valid  objection  to 
the  practice  of  carrying  up  a  ventilating  pipe  to  the  roof  from  the  house 
drain  on  the  sewer  side  of  a  disconnecting  trap.  At  ordinary  times  it  may 
serve  as  an  exit  for  sewer  air,  but  when  its  services  are  most  required  it  is 
liable  to  fail. 

The  simplest  method  of  ventilation,  and  the  only  one  that  is  in  most 
cases  practicable,  is  to  construct  a  shaft  leading  fi-om  the  crown  of  the  sewer 
to  the  surface  of  the  roadway  above,  the  opening  at  this  spot  being  protected 
by  an  iron  grid.  Immediately  below  the  gratings  should  be  fixed  a  dirt-box 
to  catch  mud  and  gravel  that  would  otherwise  fall  into  the  sewer,  a  space 
being  left  around  the  box  for  the  passage  of  air  to  and  from  the  sewer. 

These  surface  roadway  ventilators  should  be  constructed  at  not  greater 
distances  apart  than  100  yards — say  eighteen  to  a  mile — and  where  the  sewers 
are  flat,  or  for  any  reason  not  self-cleansing,  the  ventilators  should  be  even 
nearer  together.  In  the  metropolis  the  average  distance  apart  is  120  yards, 
and  the  shafts  are  circular  in  shape  and  about  18  in.  in  diameter,  with  a 
superficial  area  for  ventilation  of  254-5  square  inches.  The  openings  in  the 
gratings  are,  however,  very  much  smaller,  varying  from  27  up  to  70  in.  of 
superficial  area,  and  thus  the  large  size  of  the  shafts  is  rendered  absolutely 
inoperative  by  the  small  size  of  the  gratings. 

Another  plan  which  is  largely  adopted  is  to  combine  a  ventilator  with  a 
vertical  manhole  (fig.  179).  A  ventilating  shaft  is  smik  for  some  distance  by 
the  side  of  the  manhole,  and  openings  are  left  between  them  for  the  passage 
•of  air.  Mud  and  stones  falling  into  the  ventilator  can  be  removed  through 
the  manhole  by  the  scavenger,  but  the  water  is  carried  by  a  pipe  into  the 
sewer  beneath. 

Some  of  these  surface  ventilators  will  be  found  to  act  as  inlets  for  fresh 
air,  and  others  as  exits  for  foul  air,  varying  from  day  to  day,  and  from  hour 
to  hour,  according  to  the  special  circumstances  affecting  the  movements  of 
the  sewer  air,  as  previously  described.  The  sewer  air  escapes  towards  the 
centre  of  the  roadway,  where  it  is  rapidly  diluted  with  fresh  air,  with  the 
least  chance  of  oflence  to  foot  passengers  on  the  sidewalks,  or  of  finding  an 
entrance  into  houses  through  open  doors  and  windows. 

Nevertheless,  these  surface  ventilators  are  often  productive  of  considerable 
nuisance  in  hot  weather  or  during  periods  of  drought.  The  ofi"ensive  smells 
that  are  then  perceptible  are  a  warning  that  a  deposit  of  sediment  has  taken 
place  in  the  sewer  below,  and  when  this  is  removed  or  flushed  away  the 
nuisance  ceases.  There  may  not,  however,  be  sufficient  dilution  of  the  sewer 
air  with  fi-esh  air,  and  then  it  becomes  necessary  to  increase  the  number  of 
roadway  ventilators,  or  to  supplement  their  action  by  constructing  shafts 
6  in.  or  more  in  diameter,  leading  from  the  crown  of  the  sewer  to  the  side  of 
the  road  and  thence  up  houses  or  buildings,  clear  away  from  all  windows  and 
chimneys.    These  shafts,  being  carried  up  to  a  considerable  height  above  the 


TRE  DISPOSAL   OF  BEFUSE  845 

ground,  will  act  principally  as  exits  for  foul  air;  whilst  the  surface  ventilators 
will  become  inlets  for  fresh  air,  and  nuisance  arising  from  the  escape  of  sewer 
air  in  the  streets  will  be  to  a  great  extent  obviated. 

These  shafts  have  proved  of  great  service  for  ventilating  the  upper  or 
dead  ends  of  sewers  in  narrow  enclosed  courts  or  streets,  where  the  sewer  air 
escaping  from  the  surface  ventilators  is  not  rapidly  diluted  by  fresh  air  owing 
to  the  obstruction  offered  by  surrounding  buildings.  In  these  cases  con- 
siderable collections  of  foul  sewer  air,  productive  of  great  nuisance  and 
injury  to  the  health  of  the  inmates  in  the  surrounding  houses,  may  occur 
on  calm  days. 

Pipe  ventilation  up  the  sides  of  the  houses  should  be  used  to  supplement 
the  existing  surface  roadway  ventilation,  and  not  to  take  its  place.  For,  if 
used  for  the  latter  purpose,  the  efficiency  of  the  whole  sewer  ventilation  would 
be  greatly  impaired  by  the  obstruction  offered  to  the  passage  of  air  in  these 
long  pipes  with  their  numerous  bends  and  turns.  In  any  case  they  must  be 
fixed  with  great  care  to  the  houses,  and  the  joints  must  be  made  thoroughly 
secure  to  avoid  any  risk  of  foul  air  entering  houses  through  windows  and 
chimneys.  It  is,  perhaps,  for  this  reason  that  local  authorities  have  found 
so  much  difficulty  in  obtaining  the  consent  of  house  owners  to  the  erection 
of  these  shafts  against  their  outer  walls. 

Street  gullies  should  not  be  used  as  sewer  ventilators,  but  should  be 
effectually  sealed  with  water,  both  to  prevent  road  detritus  entering  the 
sewers,  and  to  prevent  the  escape  of  sewer  exhalations  close  to  the  footways 
and  the  fronts  of  houses.  In  dry  weather,  street  gullies  should  be  periodically 
recharged  with  water  from  a  watering  cart. 

It  was  formerly  the  custom  to  filter  the  sewer  air  escaping  from  the 
manhole  and  other  surface  ventilators  through  wood  charcoal  contained 
in  iron-wire  baskets  ;  but  it  soon  came  to  be  recognised  that  the  deodorisa- 
tion  of  the  sewer  air  lasted  only  so  long  as  the  charcoal  was  dry,  and  that 
when  the  charcoal  became  damp — as  it  very  soon  did — its  pores  were  clogged, 
and  then  it  obstructed  all  passage  of  air.  There  can  be  no  doubt  that,  when 
dry,  wood  charcoal  has  considerable  effect  in  deodorising  sewer  air  by  oxidis- 
ing organic  vapours,  as  is  shown  by  the  fact  that  nitrates  and  ammoniacal 
compounds  can  be  recovered  from  the  used  charcoal.  But  when  placed  in 
the  ventilators  it  soon  becomes  wet  from  rain  and  moisture,  and  requires  to 
be  recarbonised  about  once  every  month  or  six  weeks.  For  these  reasons 
charcoal  filters  have  now  been  nearly  everywhere  discontinued. 

Various  other  plans  have  from  time  to  time  been  suggested,  with  a  view 
to  the  deodorisation  of  the  sewer  air  escaping  from  ventilators  by  means  of 
chemical  gases  or  solutions  of  supposed  antiseptic  properties.  And  a  method 
of  passing  all  the  air  so  escaping  through  a  ring  of  gas  burners,  known  as 
Keeling's  Extractor,  has  also  been  tried.  Here  the  escaping  gases  are 
actually  burnt,  or  at  least  very  highly  heated.  The  same  objections  apply  to 
all  such  methods.  Their  initial  cost  is  large  ;  they  require  a  considerable 
amount  of  attention,  involving  labour  and  expense ;  and  if  they  are  successful 
in  accomplishing  what  they  are  intended  to  do,  viz.  the  mitigation  or  preven- 
tion of  nuisance,  they  tend  to  conceal  a  condition  of  things  in  the  sewers  which 
is  in  itself  injurious,  and  which  being  unknown  or  unnoticed,  fails  to  receive 
the  proper  remedy.  They  do  not,  therefore,  in  any  way  go  to  the  root  of  the 
evil,  but  gloss  it  over  by  getting  rid  of  the  chief  evidence  of  its  existence. 

In  sewers  laid  with  steep  gradients  a  current  of  au*  tends  to  pass  up  from 
the  low  to  the  high  levels  in  the  reverse  direction  to  the  flow  of  sewage. 
This  is  more  especially  likely  to  happen  in  cold  weather,  when  the  sewer  air 
is  at  a  considerably  higher  temperature  than  the  external  atmosphere.     The 


8i6 


HYGIENE 


offensive  gases  escape  at  tbe  liigh  levels,  and  are  the  subject  of  very  general 
complaint.  The  remedy  lies  in  constructing  at  various  points  on  the  sewers 
of  steep  gradient  a  tumbhng  bay  with  manhole  and  ventilator  (fig.  180),  and 
with  a  flap-valve  applied  to  the  mouth  of  the  sewer  delivering  sewage  from 
the  higher  level.  Then  the  sewer  air  in  its  course  upwards  meeting  the 
flap-valve  is  forced  to  escape  into  the  outer  air  through  the  ventilator,  and 
so  does  not  reach  the  higher  part  of  the  sewer. 

The  plan  of  connecting  sewers  with  the  chimneys  of  furnaces  has  now 
been  abandoned.  The  draught  up  the  chimney  creates  a  very  strong  current 
of  air  in  the  sewer  for  a  short  distance,  but  the  efl'ect  very  rapidly  diminishes 
as  tbe  distance,  increases,  for  air  rushes  in  from  all  openings  in  the  nei<i-h- 
bourhood  to  supply  the  place  of  that  extracted  by  the  furnace.  In  this  way 
the  traps  on  house  drains  and  pipes  are  liable  to  be  drawn,  and  when  the 
furnace  is  not  working  foul  air  may  pass  back  into  the  houses.     There  is 

besides  the  risk  of  an 
explosion  from  ignition 
of  coal  gas  which  may 
accidentally  find  its  way 
into  the  sewer,  as  hap- 
pened in  Southwark, 
where  the  sewers  were 
connected-  with  the  fur- 
naces of  soap  works. 

The  ventilation  of 
pipe  sewers  is  a  subject 
which  has  been  care- 
fully considered  by  Dr. 
Buchanan  in  his  report 
upon  the  epidemic  of 
enteric  fever  at  Croydon 
m  1875.  There  is  much 
less  tendency  to  the  de- 
posit of  sediment  in  pipe 
sewers  than  in  brick 
sewers,  owing  to  the 
smooth  internal  walls  of 
the  former,  and  to  the 
frequency  with  which 
ihey  are  runnmg  full  or  nearly  full,  so  that  the  whole  of  the  interior  is 
periodically  washed.  For  this  reason  pipe  sewers  are  but  seldom  productive 
of  offensive  gases.  But  the  air  within  them,  if  there  are  no  ventilation  open- 
ings, is  liable  to  be  under  far  greater  pressure  than  the  air  in  the  larger  brick 
sewers,  for  the  reason  that  the  sudden  entrance  of  a  volume  of  water  into  a 
sewer  of  small  diameter  causes  a  far  greater  and  more  sudden  displacement 
of  air  than  if  it  entered  a  large  sewer,  and  that  the  air  so  displaced  has  less 
chance  of  escaping,  owing  to  the  material  of  which  the  sewer  is  made  not 
being  porous.  For  example,  the  entrance  of  a  volume  of  water  into  a  6-inch 
pipe  sewer  will  cause  a  displacement  of  air  sixteen  times  as  great  as,  and  much 
more  sudden  than,  if  the  same  volume  of  water  entered  a  2-foot  sewer.  The 
displaced  air  may  be  comparatively  inoffensive,  but,  as  Sir  George  Buchanan 
has  shown,  offensiveness  is  no  criterion  of  the  infectiveness  of  sewer  air,  and, 
as  the  Croydon  experience  proves,  the  entrance  of  such  air  through  un- 
trapped  drain  pipes  into  houses  may  be  productive  of  an  attack  of  typhoid 
fever. 


Fig.  180. — Brick  sewer  with  tumbling  bay  and  connection  with 
ventilating  manhole. 


THE  DISPOSAL   OF  BEPUSE  847 

In  the  pipe  system  of  sewerage,  then,  adequate  ventilation  is  imperatively 
needed,  and  the  shafts  required  for  this  purpose  may  be  combined  with  the 
inspection  openings  which  we  have  seen  to  be  necessary  for  the  purpose  of 
removing  obstructions  from  the  pipes. 

Outfall   Sewees 

Until  the  passing  of  theEivers  Pollution  Prevention  Act,  and  even  to  the 
present  day  in  Dublin  and  some  other  large  towns,  the  town  sewers  took  the 
shortest  available  course  to  the  banks  of  the  river  or  stream  on  which  the 
town  was  situated,  and  there  discharged  each  by  its  own  outlet.  To  prevent 
pollution  of  watercourses  in  the  centre  of  populated  districts,  it  became 
necessary  to  construct  intercepting  sewers  of  large  size  to  receive  the  sewage 
of  the  tributary  sewers.  The  intercepting  sewers  were  united  to  form  one  or 
more  large  main  outfall  sewers,  which  conveyed  the  sewage  outside  the  town 
and  conducted  it  to  the  works  constructed  for  its  purification,  or  in  its  crude 
condition  to  its  outfall  into  the  river,  as  the  case  might  be. 

Outfall  sewers  discharging  into  the  sea  or  a  tidal  river  are  very  frequently 
a  considerable  source  of  nuisance  in  towns  situated  at  so  low  a  level  that  the 
gradients  are  small,  and  the  sewage  is  tide-locked  for  some  hours  of  each 
tide.  A  tidal  valve  at  the  mouth  of  the  sewer  prevents  tlie  ingress  of  sea- 
water,  but  the  sewage  which  flows  from  the  town  during  the  tide-locked 
period  has  to  be  stored  in  the  outfall  sewer.  Here  it  stagnates,  depositing  a 
very  copious  sediment.  The  tributary  sewers  also  under  such  circumstances 
tend  to  have  sewage  backed  up  into  them,  and  the  decomposition  of  the 
sediment  gives  rise  to  so  copious  a  formation  of  gases  that  no  amount  of 
ventilation  will  quite  obviate  the  nuisance. 

Until  recently  sewage  engineers  did  not  appear  to  have  realised  the  im- 
portance of  preventing  sewage  stagnation  in  outfall  sewers,  and  placed 
too  much  confidence  in  the  scouring  effect  of  large  volumes  of  liquid  with, 
however,  but  little  head.  It  is  certainly  advisable  that,  in  all  such  cases, 
tanks  should  be  constructed  to  receive  the  sewage  delivered  by  the  outfall 
sewer,  which  can  be  subsequently  pumped  away,  or  that  steam  or  compressed 
air-pumping  machinery  should  be  utilised  to  relieve  the  sewers  of  their  tide- 
locked  sewage. 

It  sometimes  happens  that  the  sewage  of  a  town  has  to  be  carried  across 
a  valley  or  river.  If  the  outfall  sewer  is  at  too  low  a  level  to  admit  of  bridging, 
it  must  be  carried  across  by  means  of  an  inverted  siphon,  formed  of  wrought- 
iron  pipes  with  riveted  flange  joints  laid  in  the  bed  of  the  river  or  valley. 
The  sewage  must  be  strained  of  its  larger  solid  bodies  before  passing  through 
the  siphon,  or  the  siphon  must  be  periodically  flushed  to  get  rid  of  the 
accumulation  of  solid  matters  at  its  lowest  point,  resulting  eventually  in 
complete  choking,  an  occurrence  which  usually  happens  unless  the  current 
through  is  of  sufficient  velocity  to  carry  all  solid  matters  with  it.  A  ventilating 
pipe  should  be  attached  to  the  descending  arm,  to  give  exit  to  air  under 
pressure  in  the  siphon,  which  might  prevent  its  proper  action. 

The  Shone  System 

This  system  is  intended  for  use  in  towns  situated  on  low-lying  or  very 
level  ground,  where  the  sewage  has  to  be  pumped  to  the  outfall,  or  where 
the  sewers  have  to  be  laid  with  very  small  gradients.  The  leading 
feature  of  the  system  is  the  method  of  raising  the  sewage  by  means  of  com- 
pressed air  at  such  points  as  are  convenient  on  its  course  to  the  outfall. 


848 


HYGIENE 


The  air  is  compressed  at  a  central  station,  and  is  then  conveyed  by 
2-ineh  wrought-iron  pipes  to  the  ejectors,  situated  in  chambers  below  the 
surface  of  the  streets  at  different  parts  of  the  town  (fig.  181).  These  ejectors 
receive  the  sewage  from  the  street  sewers,  and  when  full  the  compressed  air 
is  admitted  into  them  by  appropriate  mechanical  arrangements,  and  the 


sewage  is  forced  out.  If  the  air  is  compressed  to  the  extent  of  15  lb.  to  the 
square  inch  (=one  atmosphere)  the  sewage  will  be  raised  to  the  height  of 
34  feet  in  the  discharge  pipe  from  the  ejector.  This  discharge  pipe  is  con- 
nected with  an  ordinary  gravitating  sewer,  or  the  ejector  discharges  directly 
into  a  '  sealed '  sewer  of  cast-iron  pipes,  when  it  is  necessary  that  the  rise 


THE  DISPOSAL   OF  BEFUSE  849 

.should  be  more  gradual  and  continued  over  a  greater  distance.  The  ejectors 
.are  placed  at  a  depth  below  the  surface  of  the  ground  sufficient  to  permit  ol 
the  house  drains  and  street  sewers  being  laid  at  good  gradients,  the  sewage 
■entering  them  by  gravitation.  The  ejectors  are  made  of  various  sizes, 
■depending  upon  the  amount  and  the  maximum  rate  of  flow  of  the  sewage 
they  are  required  to  receive. 

The  advantages  claimed  for  the  system  are  as  follows  : — 
(1)  Good  gradients  being  given  to  the  sewers,  the  sewage  is  carried  to 
ihe  ejectors,  and  forced  out  of  the  town,  in  a  fresh  and  undecomposed  state. 
(2)  No  storage  is  required,  as  in  ordinary  pumping,  where  the  rate  of  flow  of 
the  sewage  may  exceed  the  powers  of  the  machinery  ;  for  the  rate  of  working 
•of  the  ejectors  varies  with  the  rate  of  flow  of  the  sewage,  although  the  rate  of 
working  of  the  machinery  for  air  compression  is  nearly  uniform.  (3)  Com- 
pressed air  is  a  motor  that  can  be  conveyed  and  divided  amongst  any  number 
•of  stations  near  to  or  far  apart  from  each  other  without  any  appreciable  loss 
either  by  leakage  in  the  pipes,  if  properly  laid  and  jointed,  or  by  friction, 
the  only  loss  being  that  due  to  clearance  of  compressed  air  from  the  ejectors 
when  discharged.  (4)  The  air  can  be  compressed  at  one  station,  so  that  one 
staff  only  is  required,  as  in  the  case  of  a  single  outfall.  (5)  The  temperature 
of  the  compressed  air  is  very  nearly  the  same  as  that  of  the  outside  atmo- 
sphere, so  that,  as  compared  with  steam,  there  is  no  loss  of  heat  by  radiation 
from  the  pipes  conveying  it. 

Shone's  system  has  been  adopted  at  Eastbourne,  Wrexham,  Southamp- 
ton, Warrington,  Henley-on-Thames,  and  at  the  Houses  of  Parliament, 
Westminster.  It  certainly  seems  well  adapted  for  those  places  in  which 
absence  of  proper  gradients  causes  silting  up  in  the  sewers,  and  in  practice 
it  has  been  found  to  realise  the  expectations  formed  of  its  working. 

The  Librnuk  System 

In  this  system  every  house  must  be  provided  with  two  sets  of  drains — one 
for  household  waste  waters  and  rain  water,  the  other  for  the  f^cal  matters 
from  cabinets  d'aisance  without  water  supply,  for  the  water-closet  sewage, 
and  for  bedroom  slops  containing  urine.  The  first  set  of  pipes  joins  the  pipe 
drains  in  the  street,  which  receive  rain  water  and  the  waste  liquids  firom 
factories,  and  the  contents  are  finally  discharged  into  the  nearest  watercourse 
(canals  in  Holland). 

The  cabinets  d'aisance,  or  '  air-closets,'  as  they  are  termed,  consist  of 
■cast-iron  hoppers  with  siphon  traps,  but  without  water  supply.  They  are 
connected  with  the  branch  sewer  pipes  in  the  street  by  means  of  5 -inch 
cast-iron  soil  pipes,  trapped  with  a  siphon  bend  below,  and  continued  up  above 
the  roof  by  2-inch  ventilating  pipes. 

The  branch  sewer  pipes  are  also  5-inch  cast-iron  pipes  with  gas-tight 
joints.  These  pipes  are  laid  in  lengths  of  long  downward  slopes  of  1  in  250, 
and  short  upward  slopes  of  1  in  5,  forming  inverted  siphons,  where  the 
sewage  matters  rest  at  varying  heights,  according  to  the  volume  of  sewage. 
These  inverted  siphons  are  ultimately  connected  with  a  cyhndrical  iron 
reservoir  placed  below  the  surface  of  the  street  in  the  centre  of  a  district  of 
from  fifteen  to  forty  acres,  the  town  being  divided  into  these  districts.  These 
reservoirs  are  connected  with  the  works  outside  the  town,  where  air- vacuum 
pumps  are  at  work,  by  two  sets  of  pipes.  The  smaller  set  are  the  air-pipes 
opening  into  the  top  of  the  reservoir,  and  the  larger  set  opening  from  the 
bottom  of  the  resevoir  serve  for  the  transport  of  the  sewage  to  the  works. 

A  vacuum  is  produced  within  the  street  reservoir  by  connecting  it  with 

VOL.  I.  3  I 


850  HYGIENE 

the  works  ;  the  valve  on  the  street  sewer  pipes  is  then  turned,  and  the  sewage 
from  the  branch  sewers  is  sucked  into  the  reservoir.  As  soon  as  this  is 
nearly  full,  air  is  admitted,  and  the  sewage  is  then  sucked  into  a  reservoir  at 
the  works.  The  arrangement  of  the  branch  sewer  pipes  as  inverted  siphons 
causes  approximately  equal  emptying  of  their  contents  into  the  street 
reservoir.  In  those  branch  pipes  that  are  full  the  sewage  will  stand  up  to 
the  top  of  the  bend  of  the  siphon,  and  will  consequently  be  more  easily 
drawn  away  than  those  which  are  less  full,  and  in  which  the  sewage  has  to 
pass  up  a  greater  length  of  the  bend.  As  soon  as  the  levels  of  sewage  in  the 
siphons  of  all  the  branch  pipes  are  the  same,  they  are  all  emptied  equally 
until  bubbles  of  air  begin  to  pass,  when  no  more  sewage  flows,  leaving  the 
pipes  still  trapped. 

In  Amsterdam,  where  the  Liernur  system  is  at  work,  the  sewage  contains 
but  little  diluting  water,  as  the  majority  of  the  closets  in  the  town  are  '  air- 
closets  '  without  water  supply.     At  the  works  outside  the  town  the  sewage  is  ■ 
further  concentrated  by  heat,  and  dried  in  revolving  cylinders,  when  it  issues 
as  a  powder — said  to  be  worth  8  francs  per  50  kilos,  (about  6L  10s.  per  ton). 

The  system  appears  to  be  well  adapted  for  flat  towns  intersected  by 
numerous  canals,  such  as  are  to  be  found  in  Holland,  where  sewerage  by 
gravitation  presents  great  difficulties  ;  and  it  certainly  appears  as  if  it  could 
be  ordinarily  conducted  without  the  production  of  offensive  odours,  either 
given  off  from  the  street  reservoirs  or  from  the  '  air-closets '  within  the 
houses. 

The  Berliek  System 

This  system  has  been  adopted  in  one  of  the  districts  of  Paris.  In  prin- 
ciple it  is  very  similar  to  that  of  Liernur.  The  house  drains  are  connected 
with  iron  pipes,  in  which  a  partial  vacuum  is  maintained  by  means  of  an  air 
pump,  so  that  the  sewage  is  conveyed  from  the  houses  by  pneumatic  pressure 
to  the  pumping  station,  which  may  be  outside  the  town. 

The  distinguishing  feature  of  the  Berlier  system  is  its  automatic  action, ^ 
which  is  a  great  improvement  on  the  Liernur  plan,  in  which  the  pipes  and 
receivers  can  only  be  emptied  by  the  opening  of  valves  by  hand.  In  the 
Berlier  system  every  house  drain  is  provided  with  an  air-tight  receptacle,  in 
which  the  sewage  collects  until  nearly  full,  when  by  a  floating-valve  arrange- 
ment the  aperture  leading  to  the  sewer  pipes  is  automatically  opened,  and 
the  sewage  is  sucked  away. 

The  system  seems  to  be  well  adapted  for  Paris,  where  the  existing  sewers 
being  so  entirely  unsuited  to  the  water-carriage  system  of  excrement  removal, 
excretal  refuse  must  be  retained  in  the  vicinity  of  houses  m  cesspools,  or  in 
some  form  of  midden  pit  or  dry  closet,  unless  it  be  removed  in  a  system  of 
small  sewers  not  depending  on  gra\itation  as  a  motive  force. 


THE   DISPOSAL   OF   SEWAGE 

The  Elvers  Pollution  Prevention  Act  of  1876  made  it  illegal  to  discharge 
crude  sewage  into  a  stream,  this  term  including  rivers,  streams,  canals,  lakes, 
and  watercourses  other  than  those  mainly  used  as  sewers,  and  also  the  sea 
to  such  extent,  and  tidal  waters  to  such  point,  as  may  after  local  inquiry,  or 
on  sanitary  grounds,  be  determined  by  the  Local  Government  Board.  This 
Act  has  very  generally  been  disregarded  during  the  dozen  years  and  more 
it  has  been  supposed  to  have  been  in  operation,  owing  to  the  magnitude  of 
the  interests  involved  in  the  continuation  of  the  old  conditions.     By  the 


THE  DISPOSAL   OF  BEFOSE  851 

Local  Government  Act,  1888,  the  duty  of  preserving  the  purity  of  our  streams 
and  rivers  has  been  in  part  transferred  from  the  local  sanitary  authorities  to 
the  County  Councils,  and  it  is  to  be  hoped  that  this  transference  of  powers 
will  be  followed  by  a  more  adequate  enforcement  of  the  provisions  of  the 
Act. 

It  will  be  advisable  at  this  point  to  consider  briefly  the  effects  produced 
by  the  discharge  of  crude  or  incompletely  purified  sewage  into  fresh  running 
water. 

The  magnitude  of  the  evils  which  result  from  this  practice  is  to  a  con- 
siderable extent  dependent  upon  the  proportionate  volumes  of  sewage  and 
clean  water  thus  mixed  together.  If  the  sewage  is  comparatively  small  in 
volume,  and  is  at  once  largely  diluted  with  clean  river  water,  it  becomes  in 
course  of  time  to  a  great  extent  purified.  The  chief  agent  in  this  purifying 
process  is  the  atmospheric  oxygen  dissolved  in  the  water,  which  has  con- 
siderable oxidising  effect  upon  the  organic  matters  of  the  sewage.  As  this 
dissolved  oxygen  becomes  used  up,  a  fresh  supply  is  absorbed  from  the  air  ; 
but  actively  growing  aquatic  plants  also  give  off  oxygen  and  reoxygenate  the 
water,  thus  enabling  the  process  of  purification  by  oxidation  to  continue. 
Besides  the  water-plants,  minute  animals  (infusoria,  entomostraca  or  water- 
fleas,  anguillulidte  or  water- worms)  are  found  in  countless  numbers  in  the 
polluted  reaches  of  rivers  ;  and  these  feed  on  some  of  the  organic  impurities 
of  the  sewage,  and  thus  contribute  towards  the  purifying  process.  The 
coarser  kinds  of  fish,  too,  the  carp,  roach,  and  chub,  feed  on  some  of  the 
elements  of  the  sewage,  and  aid  the  process  of  purification.  The  suspended 
matters  of  the  sewage  tend  to  deposit  largely  in  streams  with  sluggish  current, 
and  thus  may  be  productive  of  nuisance  in  the  immediate  neighbourhood  of 
the  sewer  outfalls  ;  whilst  the  water  below,  being  relieved  of  their  presence, 
is  in  a  better  position  to  benefit  by  the  natural  oxidation  processes.  The 
agitation  of  the  water  and  its  exposure  to  the  air,  brought  about  by  its 
flowing  over  rapids  or  falling  over  weirs,  exerts  a  marked  beneficial  influence 
on  its  quality — no  doubt  from  the  increased  oxidation  of  organic  matters. 

That  polluted  river  waters  can  undergo  self-purification  is  now  very 
generally  recognised.  The  essential  conditions  are  that  the  polluting  liquids 
shall  be  rapidly  diluted  with  a  large  volume  of  clean  water,  allowing  the 
natural  purifying  agencies  of  oxidation  and  animal  and  vegetable  aquatic  life 
free  play.  The  completeness  with  which  this  self- purification  is  accomplished,. 
or,  in  other  words,  the  question  as  to  whether  a  river  water  once  polluted 
with  sewage  can  ever  attain  its  original  purity  or  be  a  proper  source  of  water 
supply,  is  one  which  we  are  not  called  upon  to  discuss  here.  It  is  sufficient 
to  state  that  under  favourable  conditions  polluted  river  waters  can  regain 
that  state  of  purity  which,  as  evidenced  by  chemical  and  biological  exami- 
nation, they  formerly  possessed.  But,  practically,  in  this  country  rivers 
which  are  once  polluted  with  sewage  so  continually  receive  fresh  accessions 
of  sewage  from  the  towns  situated  lower  down  on  their  banks  that  the  pro- 
cesses of  self-purification  are  brought  to  a  standstill,  and  the  contammation 
of  the  water  gradually  but  constantly  increases  from  the  source  to  the  mouth 
of  the  river. 

Under  these  circumstances  the  dilution  of  the  sewage  with  clean  water  is 
insufficient.  The  dissolved  oxygen  in  the  water  is  used  up  in  the  processes  of 
oxidation  of  organic  matters  ;  the  fish,  first  of  all,  and  subsequently  the  lower 
forms  of  animal  and  vegetable  aquatic  life,  are  destroyed  by  the  absence  of 
dissolved  oxygen  or  by  the  presence  of  noxious  organic  matters  in  the  water, 
and  then  the  natural  oxidation  processes  come  to  an  end.  Putrefactive  pro- 
cesses are  started  by  a  great  increase  in  the  numbers  of  the  bacterial  organ- 

3i2 


S52  HYGIENE 

isms,  fermentative  changes  take  place  in  tlie  organic  matters,  and  foul  gases 
are  evolved.  The  bed  of  the  river  becomes  coated  with  a  deposit  of  decaying 
sediment,  particles  of  which,  buoyed  up  by  the  gases,  occasionally  rise  to  the 
surface  to  sink  again,  and  a  nuisance  of  a  most  injurious  character  results. 

The  nuisance  is  most  marked  during  a  period  of  warm  weather.  In  the 
cooler  months  of  the  year  the  oxidation  processes  may  be  in  action  to  a  consi- 
derable extent ;  but  on  a  rise  of  temperature,  especially  if  the  volume  of  clean 
water  becomes  at  the  same  time  diminished  by  absence  of  rainfall,  the  growth 
of  bacterial  organisms  becomes  stimulated  to  such  an  extent  that  decomposi- 
tion sets  in  and  replaces  the  ordinary  processes.  This  happens  to  the  Thames 
below  London  in  the  neighbourhood  of  the  sewage  outfalls  pretty  nearly 
every  summer,  when  the  temperature  is  high  and  the  land  water  small  in 
amount.  During  the  rest  of  the  year  the  river  is  not  so  productive  of 
nuisance,  although  there  can  be  but  little  doubt  that  its  purifying  powers 
are  at  nearly  all  times  being  tested  to  the  height  of  their  capacity. 

The  discharge  of  crude  town  sewage,  then,  into  rivers  is  a  practice  fraught 
with  so  many  evils  and  dangers  that  it  cannot  be  too  strongly  condemned 
in  all  cases  where  towns  or  villages  are  situated  on  the  banks  lower  down,  or 
•derive  their  water  supply  from  the  polluted  source. 

The  discharge  of  sewage  into  the  tidal  waters  of  rivers  and  into  the  sea 
must  next  engage  our  attention  ;  and  here,  of  course,  there  can  be  no  ques- 
tion of  contaminating  potable  waters,  for  now,  at  any  rate,  the  provision 
of  water  for  domestic  purposes  from  the  tidal  portions  of  rivers  is  unknown. 

In  the  case  of  the  tidal  waters  of  rivers  the  reports  of  the  Royal  Com- 
mission on  Metropolitan  Sewage  Discharge  throw  considerable  light  on  the 
part  played  by  the  currents  and  tides  on  the  sewage  discharged  into  them, 
and  serve  entirely  to  negative  the  idea  pre'sdously  entertained  that  sewage 
■discharged  into  a  tidal  water  is  at  once  carried  away  to  sea. 

In  the  first  place,  it  is  pointed  out  that  the  only  true  sources  of  dilution 
of  the  sewage  are  the  land  water  entering  from  above,  and  the  sea  water 
passing  up  from  the  mouth  of  the  river.  The  displacement  of  the  sewage 
towards  the  sea  depends  to  a  very  great  extent  upon  the  volume  of  land  water 
entering  from  above.  When  this  is  but  slight  m  amount,  owing  to  absence 
of  rain,  the  sewage  is  displaced  towards  the  sea  with  great  slowness ;  in  the 
case  of  the  metropolitan  sewage  the  displacement  in  dry  weather  is  said  to 
be  only  a  quarter  of  a  mile  daily.  The  result  is  that  the  sewage  discharged 
at  high  water  on  any  particular  day  is  carried  down  with  the  tide  and  then 
back  again  to  within  a  very  short  distance  of  the  outfall.  At  each  high  tide 
it  receives  a  fresh  accession  of  sewage,  so  that  a  considerable  accumulation  or 
concentration  of  sewage  in  the  river  takes  place,  forming  what  has  been 
termed  a  '  sewage  zone,'  and  this  is  entirely  due  to  the  tidal  oscillations.  It  is 
evidently  a  mistake,  then,  to  regard  the  river  water  into  which  sewage  is  dis- 
charged at  Barking  or  Crossness  as  clean  water  ;  it  is,  m  fact,  water  that  by 
reason  of  the  tidal  oscillations  has  already  become  the  recipient  of  an  accumu- 
lation of  successive  previous  sewage  discharges. 

There  is  still  another  drawback  to  be  considered  in  connection  with  the 
discharge  of  sewage  into  a  tidal  river.  Any  sewage  which  is  not  discharged 
wdthin  a  short  period  after  high  water  will  be  carried  up  by  the  flowing  tide 
above  the  outfall ;  and  when  neap  tides  are  gi\'ing  place  to  spring  tides  the 
whole  volume  of  discharged  sewage  is  carried  up  daily  higher  and  higher 
above  the  sewer  outfalls  as  the  spring  tides  increase.  In  this  way  sewage 
may  be  carried  up  into  the  heart  of  London,  or  even  above  it. 

It  is  necessary,  then,  to  store  up  the  sewage  at  the  outfalls  in  a  reservoir 
and  to  discharge  it  as  quickly  as  possible  at  the  top  of  the  tide.     But  at  high 


THE   DISPOSAL   OF  BEFUSE  85^ 

water  there  is  a  larger  proportion  of  sea  water  in  the  river  than  at  any  other 
time,  and  the  various  salts  contained  in  the  sea  water  cause  a  considerable 
precipitation  of  the  organic  matters  in  the  sewage.  The  processes  of  purifica- 
tion by  oxidation  are  lessened  by  the  presence  of  these  salts,  and  there  is  a 
greater  tendency  to  the  deposition  of  sewage  mud  than  if  the  sewage  was  dis- 
charged into  fresh  water. 

The  silting  up  of  the  bed  of  the  river  and  the  formation  of  mud  banks  and 
shoals  is  a  very  serious  matter  in  the  case  of  navigable  waterways.  There 
can  be  little  doubt  that  the  solid  matters  of  the  sewage  are  largely  deposited 
in  the  neighbourhood  of  the  sewer  outfalls,  and  are  not  to  any  great  extent 
carried  out  to  sea  in  a  state  of  suspension  in  the  water. 

The  nuisance  that  may  result  from  the  emanations  of  a  sewage-polluted 
river  is  patent  to  all,  but  the  question  of  injury  to  health  from  such  emanations 
is  one  more  difficult  to  decide.  In  the  case  of  the  metropolitan  sewage  the 
Commissioners  agreed  that  indisposition  and  a  low  state  of  vitality  amongst 
those  who  were  actually  upon  the  river  or  lived  on  its  margin  might  be 
attributed  to  its  offensive  condition,  but  the  smell  was  in  no  case  perceptible 
a  short  distance  away  from  the  river  ;  and  in  the  case  of  towns  or  villages 
upon  its  banks  it  was  found  impossible  to  separate  the  influence  of  the  river 
from  other  causes  productive  of  high  mortality,  which  were  very  generally 
present. 

The  discharge  of  crude  sewage  into  the  sea  rests  upon  a  somewhat 
different  footing  from  its  discharge  into  a  tidal  river.  Here  the  volume  of  sea 
water  is  so  enormous  in  comparison  with  the  sewage  that  if  it  can  only  be 
ensured  that  the  sewage  at  once  mixes  with  a  large  volume  of  sea  water,  the 
dilution  of  the  offensive  organic  matters  is  sufficiently  complete  to  render 
them  innocuous.  Certain  conditions,  however,  must  be  observed  to  arrive  at 
so  satisfactory  a  result. 

The  position  of  the  outfall  with  regard  to  the  town  must  be  so  chosen 
that  the  sewage  will  always  be  canned  out  to  sea,  independently  of  the  tides, 
and  the  possibility  of  its  return  avoided.  Should  there  be  only  one  current, 
setting  in  at  a  particular  tide,  available  for  carrying  the  sewage  away,  then  a 
reservoir  must  be  provided  for  storing  the  sewage  at  such  states  of  the  tide 
as  are  unsuitable  to  its  discharge.  In  the  case  of  a  current  setting  along  the 
shore,  rather  than  off  it,  the  sewer  outfall  should,  of  course,  be  placed  at 
that  extremity  of  the  town  which  will  prevent  the  sewage  being  carried  along 
the  whole  sea  front.  The  prevailing  winds  must  also  be  carefully  studied,  so 
that  floating  matters  in  the  sewage  may  not  be  blown  back  towards  the  town. 
The  mouth  of  the  outfall  sewer  should  be  below  the  level  of  the  water  at  all 
states  of  the  tide,  and  should  be  provided  with  a  tidal  valve  to  prevent  the 
ingress  of  sea  water. 

In  certain  towns  where  these  conditions  have  not  been  fulfilled  the  sewage 
discharge  has  been  productive  of  much  nuisance.  The  sewage  has  been 
borne  along  the  whole  sea  front  of  a  town  by  the  set  of  the  currents,  and  foul 
matters  have  been  deposited  on  the  foreshore,  to  the  great  detriment  of  the 
health  reputation  of  these  towns  as  watering  places. 

It  is  generally  recognised  that  sewage  discharged  into  a  river  or  sea  is 
altogether  wasted  ;  but  this  opinion  is  not  shared  by  Sir  John  Lawes,  who 
believes  that  the  sewage  is  to  a  certain  extent  utilised  by  the  fish  feeding 
upon  that  which  the  sewage  produces.  The  sewage  which  is  discharged  into 
the  Thames  he  considers  to  be  at  first  more  suitable  for  animal  than  for 
vegetable  life,  but  the  products  of  the  animal  life  become  food  for  vegetation, 
and  this  vegetation  in  its  turn  is  the  food  for  fish.  The  removal  of  the 
sewage  from  the  river,  or  even  the  removal  of  the   sedimentary  portion  by 


654  HYGIENE 

means  of  lime,  would,  Sir  John  Lawes  thinks,  be  followed  by  a  most  serious 
reduction  in  the  present  quantity  of  fish.  And  he  further  adds :  '  Looking  at  the 
great  cost  which  must  be  incurred  before  the  sewage  could  be  employed 
beneficially  upon  land,  it  is  quite  probable  that  as  a  source  of  national  wealth 
its  value  is  greater  in  its  present  state  than  it  can  be  by  any  other  process 
apphed  to  it.' 

Apart,  however,  from  the  fact  that  great  injury  has  been  done  to  the  fish- 
ing interest  in  the  Thames  itself — for  the  fish  which  formerly  abounded  in 
the  river  as  high  as  London  have  now  been  driven  down  below  Gravesend  by 
the  sewage  discharge — we  have  it,  on  the  great  authority  of  Prof.  Huxley, 
that  all  the  great  sea  fisheries  are  inexhaustible  ;  that  is  to  say,  that  nothing 
man  can  do  can  seriously  affect  the  number  offish  in  the  sea.  Mr.  C.  E. 
Fryer,  of  the  Government  Fisheries  Department,  has  also  pointed  out  that  the 
fishery  of  all  others  that  has  shown  the  most  marvellous  growth  is  the  Scotch 
herring  fishery,  which  has  always  been  prosecuted  far  from  the  influence  of 
sewage  discharge,  and  is  every  year  beiiig  carried  on  more  and  more  success- 
fully at  a  greater  distance  from  the  shore.  He  also  states  that  the  600,000 
tons  of  fish  annually  brought  ashore  in  this  country  are  collected  from  an 
area  of  about  150,000  square  miles,  with  a  maximum  depth  of  about  350  feet ; 
and  he  asks,  How  are  the  constituents  of  London  sewage  to  be  spread  with 
anything  like  uniformity  over  this  vast  area  ?  We  consider,  then,  that  Sir 
John  Lawes  has  entirely  failed  to  show  that  the  sewage  cast  into  the  sea  is 
not  completely  and  utterly  wasted. 


THE   PURIFICATION   AXD   UTILISATION   OF   SEWAGE 
Its  Chemical  CoMrosiTiON  and  Value 

We  have  already  seen  that  the  discharge  of  crude  sewage  into  streams, 
the  estuaries  of  rivers,  or  into  the  sea,  means  the  entire  waste  of  such 
valuable  manurial  ingredients  as  the  sewage  may  contain.  Owing  to  the 
density  of  population  in  this  country,  and  the  large  numbers  of  towns  and 
villages  on  the  banks  of  every  stream  and  river,  the  discharge  of  crude 
sewage  into  these  watercourses  is  almost  invariably  productive  of  nuisance 
to  a  greater  or  less  extent,  and  of  injury  to  the  fishing  and  other  interests, 
which  are  entirely  dependent  upon  the  purity  of  river  water.  Li  the 
case  of  all  towns,  therefore,  which  are  unable  to  get  rid  of  their  sewage 
directly  into  the  sea,  the  problem  of  purification  of  the  sewage  before  dis- 
charge has  to  be  attacked,  and  the  question  at  once  arises — Is  it  worth  while 
to  attempt  the  utilisation  of  the  manurial  ingredients  of  the  seioage  ?  and  as 
a  corollary — Is  it  possihle  to  practically  combine  utilisation  with  purification, 
and  to  make  the  process  pay  the  whole  or  part  of  the  expenses  incurred  in 
its  adoption  ?  Our  first  concern,  then,  must  be  to  consider  what  are  the 
amounts  and  values  of  the  manurial  ingredients  contained  in  ordinary  town 
sewage,  and  how  far  is  it  possible  to  reason  from  such  theoretical  considera- 
tions on  the  value  of  sewage  or  sewage  products  to  the  practical  farmer. 

The  Eivers  Pollution  Commissioners  in  their  first  report  gave  the  average 
composition  of  sewage  in  water-closeted  towns  as  represented  in  the  table 
on  page  855. 

The  quantity  of  nitrogen  existing  as  nitrates  and  nitrites  is  inappreciable. 

This  composition  represents  an  average  of  a  large  number  of  analyses, 
and  being  merely  an  average  its  approximation  to  the  average  strength  of 
sewage  in  any  town  can  only  be  determined  by  actual  experiment  and  observa- 
tion.   The  sewage  of  different  towns  will  vary  very  greatly  in  character  accord- 


THE  DISPOSAL   OF  EFFUSE 


855 


"5ng  to  the  proportionate  number  of  water-closets  to  dry  closets  or  middens 
in  the  town,  according  to  the  amount  of  water  supply  per  head  of  the  popula- 

In  100,000  parts. 


Suspended  Matters  44-69 

Solid  Matters  in  Solution  72-2 

Organic 

Mineral 

Organic 
Carbon 

Organic 

Nitrogen 

Ammonia 

Total  Combined 
Nitrogen 

Chlorine 

20-51 

24-18 

4-696 

2-205 

6-703 

7-728 

10-66 

tion,  according  to  the  amount  and  composition  of  the  wastewaters  discharged 
from  manufactories  into  the  sewers,  and,  most  of  all,  according  to  whether 
.brick  sewers  are  in  use,  which  receive  storm  waters  and  allow  subsoil  water 
to  percolate  through  their  walls,  or  a  separate  system  of  pipe  sewers  has  been 
adopted  for  the  exclusion  of  surface  and  subsoil  water.  With  the  system 
of  pervious  drain  sewers  the  dilution  of  the  sewage  during  and  after  rainfall 
is  often  so  great  that  the  mixed  rain  and  sewage  has  very  few  of  the 
characteristics  of  sewage.  Under  the  pipe  system,  on  the  other  hand,  the 
.average  strength  of  the  sewage  tends  to  be  maintained  independently  of 
rainfall  throughout  every  day  of  the  year. 

Not  only  does  the  sewage  of  different  towns  vary  so  greatly  in  composi- 
tion, but  the  sewage  of  the  same  town — more  especially  where  the  sewers 
are  of  pervious  materials — varies  in  strength  from  day  to  day,  and  from  hour 
-to  hour.  The  daily  variations  depend  largely  upon  the  occurrence  or  absence 
■of  rain,  whilst  the  hourly  variations  are  occasioned  by  the  habits  of  the 
populations.  Thus,  the  sewage  is  strongest  during  the  hours  of  the  forenoon, 
and  its  flow  greatest,  whilst  at  night  the  sewers  may  be  discharging  nothing 
but  subsoil  water. 

From  these  considerations,  then,  it  will  become  evident  that  to  obtain  an 
■exact  knowledge  of  the  average  strength  of  a  day's  sewage  in  any  town, 
samples  must  be  taken  at  least  every  hour,  and  these  samples  must  be  mixed 
:in  order  to  procure  an  average  sample  for  analysis — not  in  equal  proportions, 
but  in  such  proportions  as  are  indicated  by  gauging  the  floio  of  sewage  at 
the  time  each  sample  was  taken  (as  first  pointed  out  by  the  British  Associa- 
tion Sewage  Committee).  This  precaution  is  necessary  in  order  that  an 
average  sample  may  be  procured  ;  that  is  to  say,  a  sample  which  would 
be  identical  in  composition  with  that  which  would  be  obtained  if  the  day's 
sewage  flowed  into  a  tank  large  enough  to  contain  it  all,  and  was  well  mixed 
'before  the  sample  was  taken. 

In  the  same  way  the  average  yearly  composition  of  the  sewage  of  any 
-town  can  only  be  determined  by  the  analysis  indicated  above,  carried  on 
through  every  day  of  the  year,  and,  by  combining  these  analyses  according  to 
the  daily  volumes  of  sewage  they  represent,  in  the  same  way  as  for  the  daily 
■average.  In  practice,  however,  all  that  it  is  generally  necessary  to  know  is 
the  average  composition  of  the  dry-weather  flow  of  sewage. 

Owing  to  the  labour  involved,  calculations  of  the  average  composition  of 
sewage  as  above  have  been  little,  if  at  all,  made.  The  hourly  variations  in 
the  strength  of  town  sewage  must  more  especially  be  borne  in  mind  when  it 
is  necessary  to  determine  the  purity  of  a  sewage  effluent  from  a  purifying 
process  such  as  that  of  precipitation.  For  it  is  plain  that  if  the  samples  of 
effluent  and  sewage  are  taken  at  the  same  time  of  day,  the  effluent  does  not 
represent,  for  it  is  not  derived  from  the  sewage  arriving  at  the  works  at  that 
;precise  period,  but  is  derived  from  sewage  arriving  at  the  works  several  hours 


856 


HYGIENE 


before,  which  may  have  been  night  sewage,  and  therefore  Uttle  but  subsoil' 
water. 

The  chief  valuable  ingredients  of  sewage  are  the  different  forms  of  combined 
nitrogen,  the  phosphates,  and  the  salts  of  potassium.  The  Rivers  Pollution 
Commissioners  gave  the  money  value  of  these  constituents  dissolced  in  100 
tons  of  average  sewage  of  the  composition  given  above  as  being  about 
15s.,  whilst  the  suspended  matters  contain  only  about  2s.  worth  of  them; 
total  value,  therefore,  17s.  This  gives  a  value  to  the  sewage  of  a  fraction 
over  2d.  per  ton.  It  has  already  been  shown  that  the  annual  excretal  refuse 
of  an  individual  of  a  mixed  population  may  be  taken  as  being  equivalent  to 
10  lbs.  of  ammonia,  worth  6s.  M. ;  and  this  refuse,  if  diluted  with  water  to 
form  forty  tons  of  sewage  (corresponding  to  an  average  dilution  of  24  gallons 
per  head  daily,  which  is  the  average  dilution  of  the  dry-weather  sewage  in 
London),  will  also  give  a  value  to  the  sewage  of  Id.  per  ton.  These  values- 
decrease  with  increasing  dilution,  until  when  this  amounts  to  122|  gallons- 
per  head  daily  (or  200  tons  per  head  per  annum)  the  theoretical  value  of 
the  sewage  is  only  |(Z.  per  ton.  This  is  an  amount  of  dilution  not  infrequent 
in  London  during  periods  of  very  wet  weather.  Sewage  of  the  composition 
given  by  the  Rivers  Pollution  Commissioners  contains  about  117  parts  of 
total  solid  matters  (in  solution  and  in  suspension)  per  100,000.  It  therefore 
follows  that  855  tons  of  this  sewage  contain  one  ton  of  solid  matters,  and 
the  ammonia  in  one  ton  of  these  solids  amounts  to  179  lbs.,  worth  5Z.  4s.  5d. 
at  Id.  per  lb.,  the  remaining  valuable  ingredients  being  worth  2^.  Os.  lld.y 
or  the  value  of  the  whole  11.  5s.  id. 

We  have  already  alluded  to  the  character  of  the  sewage  in  the  midden  or 
non-water-closeted  towns,  and  sho-svii  that  in  composition  it  does  not  differ  in 
any  very  material  respects  from  that  of  the  water-closeted  towns  (see  p.  854). 
The  Rivers  Pollution  Commissioners  gave  the  following  as  the  average  com- 
position of  midden  town  sewage  : — 

In  100,000  parts. 


Suspended  Matters  39-11 

Solids  in  Solution  82-4 

Organic 

Mineral 

Organic 
Carbon 

Organic 
Nitrogen 

Ammonia 

Nitrogen  as 
Nitrates 

TotalCombined  '    , ,     . 
Nitrogen      j  Chlonne 

21-3 

17-81 

4-181 

1-975 

5-435 

0 

6-451        1  11-54 

On  comparing  this  analysis  with  that  of  the  water-closet  sewage,  it  will 
be  seen  that  the  suspended  matters  are  somewhat  less  in  amount,  whilst  the 
solids  in  solution  are  greater.  The  total  combined  nitrogen  is  also  below 
that  of  the  water-closet  sewage,  but  the  chlorine  is  in  excess,  more  persons 
contributing  to  a  given  volume  of  sewage  in  midden  towns  than  in  water- 
closet  towns,  owing  to  the  absence  of  the  water  used  in  flushing  the  closets 
of  the  latter. 

Nearly  all  the  processes  for  purifying  and  utilising  sewage  fall  under  two 
heads,  \'iz.  those  in  which  an  attempt  is  made  to  separate  the  polluting 
— which  are  also  the  manurial — ingredients  of  the  sewage  from  the  water, 
which  is  the  vehicle  for  their  conveyance,  and  those  in  wliich  the  sewage  is 
conveyed  directly  to  and  disposed  of  on  land.  In  the  first  class  may  be  con- 
sidered those  processes  of  straining,  subsidence,  and  precipitation  which 
aim  at  removing  the  suspended  matters,  at  any  rate,  from  the  sewage,  to  be 
subsequently  manipulated  into  a  more  or  less  convenient  form  for  application 
to  land  as  solid  manures,  whilst  the  liquid  in  a  clarified  condition  is  allowed 
to  discharge  at  once,  or  after  filtration  through  specially  constructed  filter 


THE  DISPOSAL   OF  REFUSE  857 

beds  into  the  nearest  watercourse.  This  subsequent  filtration  has  been 
adopted,  as  we  shall  see  later  on,  in  order  that  the  effluent  liquid  may  attain 
to  some  compulsory  or  otherwise  satisfactory  standard  of  purity. 

Steaining,  Subsidence,  and  Pbecipitation 

In  some  few  towns  at  a  former  time  attempts  were  made  to  strain 
the  sewage  by  passing  it  through  filters  constructed  of  gravel,  ashes,  or 
charcoal.  The  sewage  was  deprived  of  its  suspended  matters,  but  the  filters 
very  rapidly  became  choked,  and  had  to  be  renewed  at  very  great  cost  at 
frequent  intervals.  Although  the  sewage  is  clarified  when  the  filtering 
medium  is  new,  it  was  found  that  when  not  renewed  with  sufficient  frequency 
it  became  possible  for  the  effluent  water  to  pass  away  with  even  more  valu- 
able elements  than  the  raw  sewage  itself  possessed.  The  manure,  too,  pro- 
duced by  the  retention  of  the  sohd  matters  in  the  filter  was  only  usefully 
employed,  owing  to  its  admixture  with  ashes  or  charcoal,  to  mix  with  and 
lighten  stiff  soils.  It  was  not  in  itself  a  fertiliser  of  any  but  the  slightest 
value.  Owing  to  the  great  cost  incurred  in  the  frequent  reconstruction 
of  the  filters,  and  to  the  fact  that  the  sewage  so  treated  was  only  clarified,  and 
in  no  degree  deprived  of  its  soluble  polluting  ingredients,  these  processes  of 
straining  or  simple  filtration  have  been  everywhere  now  discontinued. 

When  sewage  is  allowed  to  settle  in  tanks,  the  suspended  matters  in 
course  of  time  subside  to  the  bottom,  and  a  more  or  less  clarified  liquid  can 
be  decanted  from  the  top  of  the  tanks.  In  this  way,  then,  it  is  possible  to 
attain  quite  as  good  a  result  as  with  the  filters  previously  described,  and 
without  the  inconvenience  and  cost  arising  from  the  periodical  renewal  of  the 
filtering  medium.  But  the  subsidence  of  the  suspended  matters  in  sewage 
is  a  slow  process,  necessitating  the  provision  of  large  tanks  for  the  sewage  to 
settle  in  and  the  expenditure  of  large  sums  of  money  in  their  construction 
and  in  the  acquisition  of  the  requisite  land. 

It  soon  came  to  be  recognised  that  the  addition  of  certain  chemical  sub- 
stances to  the  sewage,  when  mixed  with  it  prior  to  its  entering  the  settling 
tanks,  causes  a  more  rapid  and  copious  precipitation  of  the  suspended 
matters  than  can  be  effected  by  subsidence  alone.  By  such  means  it  was 
found  feasible  to  reduce  the  tank  accommodation,  and  at  the  same  time  to 
obtain  a  more  satisfactory  effluent. 

The  number  of  chemicals  that  have  been  used,  or  advocated,  as  precipita- 
tion agents  is  enormous.  Many  of  them  have  proved  worthless  on  practical 
trial,  whilst  others,  like  the  various  phosphate  processes,  though  shown  to  be 
effectual  as  precipitating  materials,  depended  on  what  is  now  known  to  be 
the  wrong  principle  of  introducing  valuable  substances  into  the  sewage  in 
the  hope  of  recovering  them  in  the  deposited  sludge  to  which  they  would 
give  a  certain  fictitious  value.  Others,  again,  have  been  abandoned  as 
being  more  expensive  than  certain  cheaper  substances,  whilst  not  giving  any 
better  results.  Even  to  enumerate  all  these  various  processes  that  have 
at  one  time  or  another  been  tried  and  then  abandoned  would  be  tedious 
in  narration,  and  unproductive  in  result,  as  we  are  more  particularly  con- 
cerned here  with  those  methods  that  have  stood  the  test  of  experience  and 
are  acknowledged  to  be,  so  far  as  at  present  known,  the  best  and  readiest 
means  of  attaining  the  end  desired. 

The  three  chief  substances  on  which  at  the  present  time,  in  a  large 
majority  of  instances,  is  reliance  alone  placed  are  lime — as  lime  water  or 
as  milk  of  lime — suljyJiate  of  alumina,  and  j^'t'otosulphate  of  iron. 

Lime  exerts  a  precipitating  effect  upon  sewage  by  combining  with  free 


658  HYGIENE 

carbonic  acid  in  the  water,  and  with  the  partially  combined  carbonic  acid  of 
the  bicarbonate  of  calcium,  forming  an  insoluble  carbonate  of  calcium 
(chalk)  which  is  deposited  ;  and  this  precipitate  carries  down  with  it  most 
of  the  suspended  organic  matters  of  the  sewage.  These  substances  sink 
to  the  bottom  of  the  settling  tank,  and  form  the  so-called  '  sludge '  of 
sewage.  The  clear  supernatant  liquid  remains  above,  and  is  known  as  the 
'  effluent.' 

Lime  has  been  longer  in  use  as  a  precipitation  material  than  any  other 
substance.  Leicester,  Tottenham,  and  Blackburn  were  among  the  first 
towns  to  adopt  the  lime  treatment  of  sewage.  Until  recently  it  was  generally 
iised  as  cream  or  milk  of  lime  (lime  slaked  and  mixed  with  water)  in  the 
proportion  of  some  fifteen  grains  of  the  lime  to  the  gallon  of  sewage.  Within 
the  last  few  years  lime  water  (lime  dissolved  in  water)  has  been  recommended 
as  being  equally  efficacious  with  a  proportionally  less  quantity  to  the  gallon 
-of  sewage — viz.  five  grains  instead  of  fifteen. 

There  can  be  no  doubt  that  the  lime  process,  when  worked  under  the 
proper  conditions  of  a  sufficient  quantity  of  the  precipitant  intimately  mixed 
with  the  sewage,  and  of  adequate  tank  accommodation  for  settling,  can  be 
made  to  effect  a  very  complete  deposition  of  the  suspended  matters  of  the 
sewage,  and  that  thei-eby  it  is  possible  to  remove  the  grosser  sewage  odour 
fi'om  the  effluent.  The  treatment  has,  however,  very  little,  if  any,  efiect  in 
precipitatmg  the  organic  matters  in  solution,  and  the  ammonia  likewise 
remains  unaffected,  so  that  the  effluent  water  carries  with  it  nearly  all  the 
valuable  manunal  ingredients  of  the  sewage,  and  the  sludge  left  at  the  bottom 
of  the  tanks  is  comparatively  worthless.  If  the  hme  is  used  in  too  great  a 
quantity,  the  sludge  and  effluent  are  rendered  distinctly  alkaline,  and  the 
tendency  to  secondary  fermentation  and  decomposition  is  much  promoted. 
It  seems  also  that  the  use  of  an  excessive  quantity  of  lime,  while  affording  a 
rapid  settlement  of  the  sludge  and  a  very  clear  effluent,  dissolves  a  consi- 
derable quantity  of  the  offensive  matters  previously  in  suspension,  and  thus 
renders  the  effluent  stronger  and  fouler  than  it  need  be.  This  constitutes 
the  great  drawback  to  the  use  of  lime  alone  in  the  treatment  of  sewage,  as 
it  is  of  the  greatest  importance  that  the  effluent  should  be  discharged  in  as 
fresh  a  condition  as  possible,  and  that  the  sludge  should  not  putrefy  whilst 
•collected  in  pits  prior  to  pressing  or  drying.  There  is,  besides,  a  tendency 
when  the  sludge  is  alkaline  for  it  to  lose  what  little  ammonia  it  may  possess 
in  the  process  of  drying. 

The  precipitation  effected  by  sulphate  of  alumina  is  due  to  its  combina- 
tion with  lime  or  carbonate  of  calcium  in  the  alkaline  sewage  to  form  sulphate 
of  calcium,  whilst  the  aluminium  hydrate  is  precipitated  in  a  flocculent  state, 
entangling  and  carrying  down  much  of  the  suspended  organic  matters,  whilst 
some  slight  portion  of  the  soluble  organic  matters  is  also  thrown  down. 
In  some  cases  as  much  as  5  per  cent,  of  these  soluble  matters  may  be 
deposited  with  the  rest  of  the  precipitate.  In  other  respects  the  effect  pro- 
duced is  very  much  the  same  as  that  resulting  from  the  lime  treatment ;  that 
is  to  say,  the  sewage  is  clarified,  but  still  contains  the  greater  portion  of 
its  polluting  and  nearly  all  its  valuable  manurial  ingredients.  The  crude 
sulphate  of  alumina,  however,  which  is  generally  used  being  somewhat  acid, 
the  sludge  and  effluent  are  neutral  or  even  faintly  acid.  There  is,  therefore, 
less  proneness  to  decomposition  than  is  the  case  with  the  alkaline  sewage 
sludge  and  effluent  resulting  from  the  lime  process,  and  in  this  important 
respect  sulphate  of  alumina  is  undoubtedly  superior  to  lime.  But  there  is  the 
drawback  that  an  acid  effluent  is  harmful  to  vegetation,  and  therefore  is  less 
suitable  as  an  irrigating  liquid  for  land  than  an  alkaline  effluent ;  and,  as  we 


THE  DISPOSAL   OF  REFUSE  859 

.shall  presently  see,  inasmuch  as  the  clarified  sewage  from  a  precipitation 
process  can  be  very  effectually  purified  on  a  very  small  area  of  land,  this  is  a 
practice  which  is  coming  much  into  fa-vour. 

Lime  and  sulphate  of  alumina  have  been  nscd  togetlier  at  various  towns 
in  this  country — for  instance,  at  Coventry  and  Hertford,  to  cite  well-known 
examples— and,  on  the  whole,  these  two  agents  are  still  generally  recognised 
.as  practically  the  best  precipitation  agents  when  used  in  combination.  The 
proportions  in  which  they  are  employed  should  be  such  as  to  render  the 

•  efauent  as  nearly  neutral  as  possible.  Where  sewage  of  medium  strength  is 
to  be  treated,  the  quantity  of  lime  used  may  be  from  five  to  seven  grains  per 
gallon,  and  of  sulphate  of  alumina  about  five  grains  per  gallon  of  sewage. 
It  is,  perhaps,  hardly  necessary  to  add  that  when  used  in  combination  the 

•  effect  of  these  salts  upon  the  sewage  does  not  very  materially  differ  from  the 

■  effect  that  would  be  produced  by  an  equal  quantity  of  either.  The  matters 
in  solution  in  the  sewage  are  but  little  affected  by  any  chemical  precipitant,  or 

•  combination  of  precipitants,  yet  discovered.  The  special  advantage  of  the 
■combination  of  lime  and  sulphate  of  alumina  is  the  production  of  a  neutral 

■  effluent  and  sludge. 

Protosulphate  of  iron  is  used  as  a  precipitating  material  by  itself  or  as  an 
adjunct  to  lime.  It  is  essential  that  the  sewage  with  which  it  is  mixed 
should  be  alkaline  ;  hence  its  frequent  use  in  combination  with  lime.  When 
so  used,  it  forms  a  highly  flocculent  hydrated  protoxide  of  iron,  which,  in 
falling  to  the  bottom  of  the  settling  tank,  carries  the  suspended  matters  of 
the  sewage  with  it.  According  to  Dr.  Stevenson,  this  protoxide  of  iron  acts 
as  a  carrier  of  oxygen,  absorbing  free  oxygen  and  again  giving  it  up  to 
>  organic  matters,  just  as  the  red  blood  pigment  absorbs  oxygen  to  again  give 
it  to  the  effete  tissues.  It  therefore  has  a  distinct  purifying  action  on 
sewage  by  oxidation  of  organic  matters  when  used  in  sufficient  quantities. 
It  also  has  considerable  antiseptic  properties,  and  tends  to  prevent  the  occur- 
rence of  putrefactive  processes  in  the  sludge  and  effluent.  By  the  use  of 
protosulphate  of  iron,  however,  the  mud  banks  of  the  stream  into  which  the 
■effluent  is  discharged  become  blackened,  owing  to  the  formation  of  sulphide 

■  of  iron.  This  is  a  disadvantage  from  a  sentimental,  but  not  from  a  sanitary, 
point  of  view. 

Protosulphate  of  iron  has  been  but  little  used  alone  as  a  precipitating 
agent.  When  used  as  an  adjunct  to  the  lime  treatment  it  should  be  em- 
ployed in  about  the  proportion  of  from  three  to  five  grains  per  gallon  of 
;  sewage.  Mr.  Dibdin,  in  the  course  of  some  experiments  on  the  metropolitan 
sewage,  found  that  on  some  occasions,  especially  on  Saturdays,  lime  would 
-not  precipitate  the  sewage  completely,  a  heavy  scum  rising  to  the  surface, 
which  was  carried  down  on  adding  a  little  iron.  This  result  he  attributed 
to  the  unusually  large  amount  of  soap  used  on  Saturdays  for  washmg  pur- 
poses. 

The  effect  of  the  precipitants  used  on  the  sludge  must  be  considered,  as 
well  as  their  ability  to  produce  a  well-clarified  effluent.  Sulphate  of  alumina 
is  said  to  increase  the  bulk  of  the  sludge,  owing  to  the  fact  that  alumina 

■  carries  down  with  it  a  good  deal  of  water,  but  the  sludge  is  more  easily  pressed 
into  cakes  than  when  lime  and  iron  are  used.  Precipitation  by  lime  and  iron, 
however,  is  more  rapid  than  by  any  other  process,  and  the  iron  tends  to  pro- 
duce a  dense  sludge.  It  is  very  often  the  practice  to  add  some  hme  to  the 
wet  sludge  before  pressing,  even  when  hme  is  used  to  precipitate  the  sewage, 
■in  order  to  secure  a  coherent  cake.  What  should  be  aimed  at  is  to  procure 
rapid  precipitation  of  a  sludge  of  but  little  bulk,  which  can  be  subsequently 

-^easily  pressed  into  cakes. 


8G0  HYGIENE 

It  is  probable  that  a  combination  of  the  three  materials  we  have  been 
eonsidering  is  capable  of  producing  the  most  highly  clarified  effluent,  and,, 
at  the  same  time,  a  sludge  which  is  most  easily  dealt  with.  The  lime  and. 
sulphate  of  alumina  should  be  used  in  about  equal  proportions,  viz.  about 
four  or  five  grains  to  the  gallon  of  sewage,  whilst  the  iron  may  be  less  (about 
two  or  three  grains  to  the  gallon).  It  is  certainly  advisable  that  the  whole- 
quantity  of  chemicals  used  should  not  exceed  fifteen  grains  to  the  gallon. 
The  question  of  cost  is,  however,  of  much  importance  in  considering  this 
matter,  for,  inasmuch  as  the  best  chemical  process  cannot  purify  sewage,  but 
only  clarify  it,  it  is  almost  always  highly  desirable  that  the  effluent  from  a  pre- 
cipitation process  should  be  further  purified  by  filtration  through  specially 
prepared  areas  of  land  or  other  suitable  filtering  material.  In  such  cases 
all  that  is  required  of  the  precipitation  process  is  that  it  should  precipitate 
the  suspended  matters  of  the  sewage  in  a  fairly  effectual  manner,  and  should 
do  this  at  the  least  possible  cost.  The  removal  of  the  suspended  matters  is 
essential  for  the  proper  working  of  the  filter  beds,  but  the  precipitation  of 
organic  matters  in  solution  is  not  required,  as  these  will  be  purified  in  the 
subsequent  process  of  filtration.  The  cost  of  lime  is  about  11.,  of  protosul- 
phate  of  iron  21. ,  and  of  sulphate  of  alumina  31.  per  ton.  It  is  evident, 
therefore,  that  the  lime  and  iron  process  is  somewhat  less  expensive  than 
lime  and  sulphate  of  alumina,  and  that  lime  alone  is  likely  to  be  the  cheapest. 
The  only  disadvantage  of  the  lime  process  is  the  alkaline  sludge  ;  but  if  this 
is  pressed,  no  nuisance  need  arise,  so  that  in  those  cases  where  the  effluent  is. 
purified  by  filtration,  treatment  by  lime  alone  is  capable  of  doing  satisfactorily 
all  that  is  required,  and  at  the  least  cost. 

The  lime  process  is  especially  adapted  for  the  preliminary  treatment  of 
the  sewage  of  those  manufacturing  towns  where  free  acids  and  acid  salts  or 
metals  in  solution  are  discharged  into  the  sewers  with  the  waste  waters  of 
factories.  If  lime  is  used  these  matters  are,  to  a  great  extent,  precipitated, 
the  acidity  is  neutralised,  and  the  effluent  sewage  can  be  used  to  irrigate 
land  growing  crops.  This  is  the  process  adopted  at  Birmingham,  where  the- 
sewage  contains  immense  quantities  of  '  pickling  liquor  ; '  milk  of  lime,  in  the- 
proportion  of  fifteen  grains  to  the  gallon,  is  mixed  with  the  sewage  prior  to 
its  entering  the  settling  tanks. 

Amongst  other  materials  used  in  combination  with  lime,  iron,  or  sulphate 
of  alumina  may  be  mentioned  clay,  which  is  ground  very  fine,  and  subse- 
quently mixed  with  the  other  precipitants,  before  being  introduced  into  the 
sewage.  It  acts  as  a  weighting  material,  causing  a  rapid  deposition  of  the 
suspended  matters,  its  effect  being  chiefly  mechanical.  It,  however,  con- 
siderably increases  the  weight  of  the  sludge  to  be  dealt  with,  and  for  this 
reason  its  use  is  in  no  great  favour. 

Animal  charcoal  and  various  forms  of  prepared  carbon  have  also  been 
tried  for  their  deodorant  properties,  but  it  is  doubtful  if  the  benefit  to  be 
derived  is  equivalent  to  the  enhanced  cost  introduced  by  such  expensive  re- 
agents. 

To  ensure  the  most  complete  clarification  of  the  sewage  the  following 
conditions  must  be  fulfilled  : — The  sewage  to  be  treated  must  be  fi'esh  and 
undecomposed,  and  the  larger  solid  matters  should  be  removed  from  it  by 
means  of  a  Latham's  extractor  before  the  admixture  of  the  chemicals,  or  by 
straining  the  sewage  through  a  metallic  sieve  with  fine  meshes.  The 
chemicals  must  be  added  to  the  sewage  before  it  arrives  at  the  tanks,  and  at. 
a  spot  a  short  distance  from  them,  so  that  in  its  flow  along  the  channel  the 
sewage  and  chemicals  become  well  mixed  together.  The  admixture  may 
also  be  accomplished  by  stirring  up  the  liquid  with  rotatory  beaters.     There 


THE  DISPOSAL   OF  BEFUSE  8G1 

must  be  sufficient  tank  accommodation.  The  tanks  are  best  arranged  in 
series,  so  that  the  sewage  may  pass  through  two,  three,  or  four  tanks,  according 
to  circumstances.  A  double  set  should  be  provided,  in  order  that  the  treat- 
ment of  the  sewage  may  continue  at  all  times.  The  sludge  must  be  removed 
frequently,  but,  of  course,  sufficient  time  must  be  given  for  it  to  settle  in 
the  tanks.  If  allowed  to  remain  too  long  it  will  putrefy  and  give  rise  to 
nuisance.  When  emptied,  the  tanks  must  be  thoroughly  cleansed  before  . 
being  refilled.  When  the  clarified  effluent  is  discharged  direct  into  a  stream, 
it  should  be  made  to  flow  in  a  broad  but  thin  stream  down  a  rapid  incline, 
and  fall  over  a  weir  so  as  to  secure  its  aeration ;  and  with  the  same  view 
the  effluent  channel  should  be  at  least  a  quarter  of  a  mile  in  length,  and 
kept  scrupulously  clean. 

In  most  modern  works  the  tanks  are  constructed  and  managed  somewhat 
as  follows  :  Each  tank  is  from  4  to  6  feet  in  depth,  and  is  divided  nearly  into 
two  by  a  vertical  brick  partition  parallel  to  its  longest  sides,  round  which 
partition  the  sewage  flows.  At  the  outlet  of  each  tank  should  be  built  a 
weir,  not  more  than  half  an  inch  below  the  surface  of  the  sewage,  over  which 
the  effluent  flows  into  the  next  tank  of  the  series,  or  into  the  effluent 
channel.  Under  ordinary  circumstances  the  sewage  need  only  pass— very 
slowly,  but  continuously — through  a  series  of  two  tanks  before  the  effluent 
is  discharged.  Intermittent  precipitation,  i.e.  allowing  the  sewage  a  short 
period  of  complete  rest  in  the  tanks,  has  been  tried,  but  does  not  seem  to 
produce  a  better  effluent  than  can  be  obtained  by  continuous  working ;  and 
it  requires,  besides,  greater  care  in  management.  After  from  one  to  ten 
■days  of  continuous  working,  the  flow  of  sewage  through  the  series  should 
be  discontinued,  and  the  sludge  allowed  to  settle,  the  clear  liquid  above 
Ijeing  drawn  ofl"  through  the  open  mouths  of  float  valves  into  the  effluent 
channel.  The  residuum  of  sludge  is  then  allowed  to  settle,  and  finally 
pumped  into  a  sludge  well,  from  which  it  can  be  forced  up  in  pipes  to  the 
filter  presses. 

This  sludge  contains  from  90  to  95  per  cent,  of  moisture.  It  was  formerly 
the  custom  to  allow  it  to  dry  by  exposure  to  the  air  in  pits,  but  this  method 
was  productive  of  much  nuisance  during  the  process  of  drying,  so  that  it  is 
now  the  usual  practice  to  press  part  of  the  moisture  out  of  the  sludge  in 
filter  presses  actuated  by  compressed  air,  by  which  a  solid  cake  containing 
from  50  to  60  per  cent,  of  moisture  is  produced. 

Johnson's  filter  press,  or  that  made  by  Manlove,  Alliott,  Fryer,  and  Co. 
(fig.  182),  may  be  taken,  as  a  type  of  these  machines.  It  consists  of  a  number 
of  grooved  discs  arranged  in  series,  each  disc  having  a  central  perforation, 
and  separated  from  the  disc  on  each  side  of  it  by  a  filtering  cloth.  The  liquid 
sludge  is  forced  between  the  discs  by  compressed  air  at  a  pressure  of  100  to 
120  lbs.  per  square  inch  ;  the  liquid,  being  forced  through  the  filter  cloths 
and  along  the  grooves  on  the  discs,  escapes,  whilst  the  soUd  portions  remain 
behind  between  the  discs,  to  be  subsequently  removed  as  sohd  cakes.  The 
expressed  liquid  is  clear,  but  exceedingly  rich  in  dissolved  organic  matters,  and 
very  ofl'ensive,  and  is  therefore  passed  back  into  the  outfall  sewer  to  undergo 
treatment  with  the  crude  sewage,  or,  better,  again  separately  treated. 

The  cakes  taken  from  the  filter  press  can  be  stored  without  causing  any 
nuisance,  until  they  can  be  sold  or  removed  from  the  works.  Or  they  can 
be  further  dried  in  steam-drying  cylinders,  and  then  ground  into  a  powder 
containing  about  20  per  cent,  of  moisture.  In  this  dried  granular  condition 
the  manure  is  far  more  suitable  for  application  to  land  than  in  the  form  of 
the  moist  and  coherent  cakes  which  issue  from  the  filter  presses. 

The  weight  of  sludge  cake  prodiiced  from  a  known  quantity  of  sludge 


862 


HYGIENE 


X  = 


taken  from  the  tanks  can  be  calculated  from  Professor  Robinson's  formula, 

10  W 
100 -P' 

■where  W=  weight  of  sludge  from  the  tanks,  P=  percentage  of  moisture 
remaining  in  the  pressed  sludge,  and  X=  weight  of  sludge  cake  produced. 
Mr.  Dibdin  gives  the  average  composition  of  pressed  sludge  cake  from 


the  metropolitan  sewage  (lime  and  iron  process)  as  :  moisture,  68  per 
cent. ;  organic  matter,  16'7  per  cent.  ;  mineral  matter,  25*25  per  cent.  ; 
ammonia,  1  per  cent.  ;  phosphate  of  lime,  1'44  per  cent.  On  the  cal- 
culation of  its  ammonia  being  worth  Id.  per  pound,  the  theoretical  value 
of  a  ton  of  this  sludge  cake  is  17s.     The  suspended  matters  from  about 


THE  DISPOSAL   OF  BEFUSE  8C8 

850  tons  of  sewage  will  be  required  to  produce  a  ton  of  sludge  cake 
containing  50  to  60  per  cent,  of  moisture,  so  that  on  the  supposition  of 
the  suspended  matters  in  100  tons  of  sewage  being  worth  2s.  (see  p.  856),. 
we  also  see  that  the  theoretical  value  of  a  ton  of  this  sludge  cake  is  175. 
Practically,  however,  this  material  is  almost  worthless,  being  so  little  suitable 
in  its  coherent  form  for  a  manure.  It  therefore  usually  has  to  be  given  away, 
or  even  the  farmers  may  want  a  small  premium  for  removing  it. 

As  to  the  value  of  the  more  completely  desiccated  manures  produced  by 
a  process  of  artificially  drying  the  sewage  sludge  cakes,  we  may  quote  from 
a  report  of  a  very  high  authority,  the  late  Dr.  Voelcker,  F.R.S.,  on  the 
*  Fertilising  and  Commercial  Value  of  Sewage  and  Night-soil  Manures,' 
contained  in  the  Report  of  the  Committee  of  the  Local  Government  Board 
on  Modes  of  Treating  Town  Sewage  (1876). 

The  theoretical  or  estimated  money  values  of  the  manures  were  calculated 
from  the  quantities  of  the  following  constituents  in  each,  namely,  insoluble 
phosphate  of  calcium  at  Id.  per  lb.,  soluble  phosphate  of  calcium  at  2tZ.  per  lb., 
potash  at  2(^.  per  lb.,  and  nitrogen  calculated  as  ammonia  at  Qd.  per  lb., 
these  being  the  rates  at  which  these  fertilising  constituents  of  manures  may 
be  bought  in  the  form  of  concentrated  artificial  manures,  such  as  guano, 
bone-dust,  sulphate  of  ammonium,  &c.  The  practical  or  market  values  were 
calculated  as  being  from  one-half  to  one-third  of  the  theoretical  values.  The 
difference  represents  the  greater  expense  in  carriage  and  application  to  land 
of  the  more  bulky  and  weaker  manure,  and  the  less  efficacy  and  value  of 
nitrogen  in  the  form  of  nitrogenous  organic  matter,  in  which  shape  the 
nitrogen  of  sewage  manures  principally  exists,  than  in  the  form  of  ready- 
made  ammonia.  For  it  must  not  be  forgotten  that  sewage  manures  contain 
a  large  proportion  of  matters  which  occur  in  abundance  in  all  or  almost  all 
soils,  and  which,  therefore,  having  no  commercial  value,  detract  from  the 
price  by  the  cost  of  their  carriage  and  application  to  the  land. 

As  a  further  reason  for  the  low  practical  value  of  these  manures  as  com- 
pared with  their  theoretical  values,  Dr.  Voelcker  cites  the  case  of  farmyard 
manure.  The  theoretical  value  of  a  ton  of  good  farmyard  manure  is,  he 
says,  about  15s. ;  but  good  dung  can  be  bought  in  many  places  at  5s.  per 
ton,  or  one-third  its  estimated  money  value  ;  and  practically  the  highest 
price  which  a  farmer  can  afford  to  pay  for  good  dung,  if  he  has  to  cart  it 
even  a  few  miles,  would  not  exceed  7s.  Qd.  per  ton,  one-half  its  estimated 
money  value. 


Value  of  One  Ton  o£  the  treated  Sewage  Sludge 

Theoretical 
or  Estimated 
Money  Value 

Practical  or 
Market  Value 

Bolton  sludge  from  the  '  M  and  C  '  sewage  process,  dried 

to  contain  15  per  cent,  of  moisture  .... 
Solids  drained  from  sewage  before  the  liming  process  at 

Bradford,  dried  to  contain  15  per  cent,  of  moisture  . 
Sludge  from  Bradford  sewage  works,  dried  to  contain  15 

per  cent,  of  moisture 

Sludge  from  'ABC'  process  at  Leeds,  dried  to  contain 

15  per  cent,  of  moisture 

£      s.     d. 
Ill 

0  19     3 

1  0    0| 
0  16     8| 

s.      d.        s.      d. 
7     0  to  10     6 
6     5  „     9     6 
6     8  „  10     0 
5     6  „     8     4 

In  the  '  M  and  C  '  process,  formerly  in  use  at  Bolton-le-Moors,  lime,  carbon 
(a  waste  product  of  the  prussiate  of  potash  manufacture),  house-ashes,  soda, 
and  perchloride  of  iron  were  added  to  the  sewage. 

From  Dr.  Voelcker's  report  it  appears  that  '  according  to  the  most  reliable- 
statements  the  separation  of  the  suspended  matters  of  sewage  by  precipitation 


8G4  HYGIENE 

and  jBltration,  and  the  production  of  one  ton  of  dried  sewage  deposit,  apart 
from  the  costs  of  the  precipitation  agents  which  are  used,  entails  an  expense 
of  ahout  thirty  shillings  for  each  ton  of  portable  dried  sewage  manure.' 
From  the  table  of  values  above  given  it  will  be  seen  that,  according  to  Dr. 
Voelcker's  calculations,  the  cost  of  manufacture  of  every  one  of  the  manures 
there  given  considerably  exceeds  even  its  theoretical  or  estimated  money 
value,  to  say  nothing  of  its  practical  or  market  value.  It  is  possible  that  at 
the  present  time,  owing  to  improvements  in  machinery,  it  may  be  feasible  to 
turn  out  the  dried  sewage  manure  at  a  somewhat  less  cost,  but  in  any  case 
it  will  be  seen  how  hopeless  it  is  to  expect  that  the  production  of  sewage 
manures  will  repay  the  cost  of  working  a  precipitation  process,  far  less  be  the 
means  of  realising  a  profit. 

The  moist  sludge  from  the  precipitation  tanks,  which  contains  from  90  to 
95  per  cent,  of  moisture,  is,  of  com-se,  of  even  less  value  than  the  pressed 
sludge,  and  can  only  be  regarded  as  a  waste  product  which  has  to  be  got  rid 
of  "\^'ithout  nuisance.  This  is  the  \aew  taken  at  Ealing,  where  the  moist 
sludge  from  the  tanks,  after  losing  some  of  its  water  by  draining,  is  mixed 
with  about  two-thirds  its  volume  of  ashes  and  house  refuse  and  is  then 
burnt  in  a  Destructor  furnace.  Another  method  of  dealing  with  it,  where 
land  can  be  made  available  for  the  purpose,  is  that  practised  at  Birmingham. 

The  sludge  is  raised  from  a  well  in  the  floor  of  the  settling  tank  by 
revolving  buckets,  driven  by  steam,  into  temporary  wooden  carriers,  along 
which  it  flows  on  to  the  land.  Here  it  parts  with  some  of  its  moisture  to  the 
air,  and  is  then  dug  into  the  soil,  which  is  subsequently  planted  and  cropped 
for  one  year.  At  the  expiration  of  the  year  the  land  is  steam-ploughed,  and 
kept  cropped  for  two  years,  being  occasionally  used  as  a  filter  bed  for  the 
effluent  from  the  tanks,  and  when  the  two  years  have  elapsed  it  is  again  used 
for  the  reception  of  the  sludge. 

We  may  mention  another  method  of  deahng  with  the  sludge,  which 
presents  some  points  of  interest,  namely,  that  invented  by  General  Scott,  and 
known  as  the  '  sewage-cement '  process,  which  was  formerly  carried  on  at 
Ealing  and  Birmingham.  The  sewage  was  precipitated  in  the  tanks  by  lime 
and  clay,  and  the  sludge  so  produced  when  sufficiently  dry  was  placed  in  a 
kiln  and  burnt  by  intense  heat,  the  residue  being  then  ground  into  cement. 
The  great  difficulty  experienced  was  to  dry  the  moist  sludge  with  sufficient 
rapidity,  filter  presses  not  having  been  at  that  time  introduced.  By  the  use 
of  modem  filter  presses  the  sludge  precipitated  by  General  Scott's  process 
would  be  rendered  dry  enough  to  burn  into  cement,  but  the  process  does  not 
appear  to  have  been  anywhere  in  operation  in  recent  years. 

We  now  come  to  the  consideration  of  the  treatment  of  the  effluent. 
This  we  have  seen  to  be  merely  a  clarified  sewage  ;  that  is  to  say,  a  sewage 
which  is  deprived  of  the  whole  or  of  the  greater  portion  of  its  suspended 
matters,  but  still  contains  all  the  dissolved  organic  matters  of  the  sewage. 
Three  main  points  present  themselves  for  consideration  in  discussing  the 
advisability  of  discharging  an  effluent  from  precipitation  works  into  a  river. 
First,  there  is  the  question  of  nuisance  likely  to  result ;  secondly,  the  injury 
to  the  river  if  used  below  the  point  of  discharge  as  a  source  of  supply  for 
drinking  water ;  and  thirdly,  the  liability  to  injure  or  destroy  the  fish  in  the 

river. 

With  regard  to  the  question  of  nuisance  it  may  be  stated  broadly  that  no 
offence  is  likely  to  be  caused  if  the  effluent  is  sufficiently  clarified  and  is 
discharged  into  a  faMy  rapid  stream,  of  which  the  ordinary  volume  is  at  least 
ten  times  greater  than  that  of  the  effluent.  Under  such  circumstances  the 
dilution  of  the  foul  water  with  clean  is  sufficiently  great  to  enable   those 


THE  DISPOSAL   OF  BEFUSE  865 

processes  of  self- purification  previously  alluded  to  to  have  free  play.  There 
is,  however,  always  the  danger  of  the  volume  of  fresh  water  in  the  river 
undergoing  considerable  diminution  in  times  of  drought ;  and  at  such  times, 
especially  in  hot  summer  weather,  it  is  always  possible  for  the  foul  matters 
in  the  effluent  to  be  insufficiently  diluted,  when  they  will  undergo  secondary 
fermentation  ;  the  river  water  becomes  turbid,  and  in  its  bed  a  deposit  of  foul 
organic  matters  forms,  Avliich  putrefies  and  gives  rise  to  offensive  gases.  The 
silt  thus  formed  tends  to  choke  up  the  bed  of  the  stream,  and  has  to  be 
removed  at  considerable  expense  by  dredging  operations.  It  therefore  appears 
to  be  advisable  that  where  streams  are  of  very  variable  volume,  according  to 
the  season  of  the  year,  the  clarified  effluent  should  be  further  purified  before 
being  permitted  to  enter  them. 

As  regards  the  second  point,  it  is  now  universally  acknowledged  to  be  un- 
safe, or  at  least  inadvisable,  to  use  a  river  as  a  source  of  water  supply  which 
has  at  any  time  received  sewage  or  sewage  effluents  higher  up  in  its  course. 
Whether  the  sewage  can  be  sufficiently  purified  by  filtration  through  earth 
or  other  filtering  materials  to  render  the  river  into  which  it  is  ultimately  dis- 
charged a  safe  source  for  drinking  water  is  a  point  upon  which  no  very  reli- 
able evidence  is  at  present  forthcoming. 

On  the  subject  of  injury  to  fish  Mr.  Wilhs-Bund,  Chairman  of  the  Severn 
Fishery  Board,  contributed  a  very  valuable  paper  to  the  Congress  of  the 
Sanitary  Institute  at  Worcester,  1889.  He  divides  the  rivers  of  this  country 
into  four  classes,  viz.  A.  Rivers  not  containing  fish.  B.  Rivers  containing 
coarse  fish — CyprinidcB — only.  C.  Rivers  containing  coarse  fish — Gyprinidcz 
and  non-migratory  SalmonidcB.  D.  Rivers  containing  migratory  Salmonida. 
The  coarse  fish — the  Cyprinidce — are  not  injured  to  anything  like  the  same 
extent  .by  sewage  in  rivers  as  are  the  Salmonida.  Of  the  coarse  fish  the 
hardiest  are  the  carp  and  tench,  and  then,  in  a  series  of  decreasing  hardiness, 
roach,  chub,  dace,  bleak,  gudgeon,  and  minnow.  Many  of  these  fish,  as  is 
well  known,  habitually  frequent  the  sewer  outfalls  into  a  river,  and  feed  upon 
some  of  the  elements  of  the  sewage,  and  they  will  even  Hve  in  a  fairly 
clarified  sewage  effluent.  But  in  the  case  of  polluted  rivers  Mr.  Willis- 
Bund  points  out  that  it  is  not  merely  a  question  of  the  fish  being  destroyed, 
but  of  how  far  the  pollution  affects  their  numbers  and  their  size  by  inter- 
fering with  their  breeding  and  destroying  their  food,  or  by  introducing  into 
their  water  unwholesome  food.  There  is  great  reason  to  beheve  that,, 
although  in  many  polluted  rivers  the  coarser  fish  have  not  been  to  any 
great  extent  destroyed,  yet  they  have  had  their  numbers  and  the  size  of  the 
individual  fish  seriously  reduced. 

The  SalmonidcB,  on  the  other  hand,  will  only  live  in  water  that  is  practi- 
cally pure,  and  they  are  besides  of  far  greater  value  than  the  CyprinidcB. 
And  here,  again,  as  regards  the  migratory  species,  the  salmon,  it  is  not  so 
much  a  question  of  the  actual  poisoning  of  the  fish  by  noxious  sewage 
matters  as  of  the  hindrance  offered  by  polluted  reaches  of  a  river  to  the 
passage  of  the  salmon  from  the  sea  to  their  spawning  beds  in  the  river. 
If  the  pollution  is  sufficiently  concentrated  the  salmon  will  not  pass  it,  and 
being  obliged  to  spawn  in  unsuitable  places  they  gradually  become  extinct. 
Where  sewage  precipitation  works  are  being  projected  on  the  banks  of  a 
salmon  river,  it  will  be  necessary  to  secure  a  very  pure  effluent,  otherwise 
the  fish  will  be  forced  back,  for  the  concentration  of  sewage  matters  is  very 
considerable  in  the  reaches  of  the  river  in  the  immediate  neighbourhood  of 
such  works.  Mr.  Willis-Bund  therefore  suggests  that  for  each  of  the  classes 
of  river  A,  B,  C,  and  D  a  minimum  standard  of  purity  of  sewage  effluent 
should  be  agreed  upon,  and  the  Local  Government  Board  should  be  induced 

VOL.  I.  3  k 


8G6  HYGIENE 

not  to  sanction  any  scheme  for  sewage  works  on  such  rivers  the  efifluent  from 
which  did  not  come  within  the  agreed  standard. 

The  clarified  eiHuent  from  a  precipitation  process  can  only  be  effectually 
purified  by  some  method  of  filtration.  Where  land  of  good  quality  can  be 
obtained  adjoining  the  works,  the  process  of  intermittent  downward  filtra- 
tion through  specially  prepared  soil  can  be  adopted  with  the  best  results  ; 
and  this  we  shall  consider  subsequently.  Where  such  land  is  not  obtainable, 
filtration  through  magnetic  oxide  and  carbide  of  iron  can  be  made  to  give 
good  results.  A  process  of  this  nature  is  now  in  use  at  Acton  and  Hendon. 
The  filtering  material  used  is  called  '  polarite,'  and  contains  about  50  per  cent, 
of  magnetic  oxide  and  carbide  of  iron,  combined  with  sihca,  lime,  and  alumina 
in  an  insoluble  form.  The  filter  beds  consist  of  18  inches  to  2  feet  of  polarite, 
upon  which  rests  a  layer  of  sand  about  a  foot  in  depth.  The  sewage  is  pre- 
cipitated in  tanks  with  a  substance  called '  ferrozone,'  consisting  largely  of 
protosulphate  of  iron,  and  the  efliuent  is  then  passed  through  the  filter  of 
polarite.  The  sand  separates  any  suspended  matter  remaining  in  the  efiluent, 
and  the  organic  matters  in  solution  are  to  a  very  considerable  extent  oxidised 
when  brought  into  contact  with  the  polarite,  as  shown  by  the  presence  of 
nitrates  and  nitrites  in  the  filtered  water,  which  is  moreover  clear  and  colour- 
less, and  far  freer  from  organic  matters  than  the  unfiltered  effluent.  The 
sand  requires  renewal  from  time  to  time,  but  the  polarite  can  be  left  un- 
changed for  very  long  periods,  only  requiring  a  daily  rest  for  aeration  of  its 
pores.  The  slower  the  filtration — that  is  to  say,  the  longer  the  efiluent  liquid 
remains  in  contact  with  the  pores  of  the  polarite — the  greater  is  the  purifying 
effect  produced.  It  is  said  that  such  a  filter  bed  can  serve  in  place  of  a 
much  larger  area  of  land,  and  will  produce  an  equally  good  result,  one  acre 
of  filter  bed  being  sufficient  to  purify  from  one  to  two  milhon  gallons  of 
clarified  sewage  daily. 

Spencer's  magnetic  carbide  of  iron  has  also  been  tried  as  a  filtering 
material  for  sewage  effluents,  and  gives  very  similar  results.  In  fact,  the  two 
materials  are  probably  very  similar  in  nature  and  composition.  We  have 
here,  then,  a  means  by  which  without  great  expense  and  without  acquiring 
any  large  area  of  land  sewage  can  be,  with  care  and  attention,  sufficiently 
purified  to  be  rendered  admissible  into  almost  any  stream,  no  matter  what 
the  original  purity  of  its  waters.  It  is  important  to  note,  however,  that  in 
these  processes  all  the  manurial  ingredients  of  the  sewage  run  to  waste  ;  for 
we  can  hardly  regard  the  dried  sludge  as  a  valuable  product,  it  being  practi- 
cally unsaleable,  and  the  efiluent  water  containing  all  the  valuable  matters 
is  not  made  of  any  account,  for  none  of  these  matters  can  be  recovered  from 
the  filter  beds,  inasmuch  as  they  are  destroyed  in  the  process  of  oxidation. 

At  this  place  it  wiU  be  convenient  to  consider  very  shortly  some  of  the 
more  important  patented  processes  for  the  treatment  of  sewage  by  precipi- 
tation. 

The  'ABC'  process  (Sillar's  patent)  has  been  tried  at  Leamington, 
Leeds,  Bolton,  Crossness,  and  other  towns,  and  is  now  in  actual  operation  at 
Aylesbury  and  Kingston-on-Thames,  being  carried  on  by  the  Native  Guano 
Company.  A  mixture  of  charcoal,  clay,  and  blood  (in  very  small  quantity) 
is  first  mixed  with  the  sewage,  after  which  is  added  crude  sulphate  of 
alumina.  A  compound  of  manganese  and  some  other  ingredients  were 
formerly  added  as  well,  but  we  beUeve  these  are  not  now  introduced.  A 
highly  clarified  effluent  is  produced  by  the  process,  which  is,  however,  a 
costly  one.  The  sludge  is  pressed  in  filter  presses  and  subsequently  dried  in 
steam  cylinders,  and  sold  as  a  granular  manure  containing  about  20  per  cent, 
of  moisture.    The  Company  claim  that  this  manure  sells  for  31.  10s.  per  ton. 


THE  DISPOSAL   OF  BEFUSE  867 

It  is  difificult  to  understand  how  mere  dried  sewage  sludge  can  command  so 
large  a  price,  as  it  is  certain  that  it  cannot  contain  sufficient  ammonia  and 
phosphates  to  justify  any  such  value.  We  have  seen,  too,  what  value  the  late 
Dr.  Voelcker  placed  upon  the  dried  'ABC'  sludge  obtained  from  the  sewage 
of  Leeds  (see  p.  863).  But  the  advocates  of  the  process  rely  upon  the  practical 
results  obtained  by  agriculturists  from  its  use,  rather  than  upon  theoretical 
values  based  upon  analytical  data.  Until  these  practical  results  obtained  in 
the  hands  of  farmers  are  published — and  they  are  not  at  present — we  are 
not  in  a  position  to  discuss  the  question  ;  but  we  are  of  opinion  that  some 
other  explanation  is  called  for  than  that  offered  by  Mr.  Sillar  to  the  Royal 
Commission  on  Metropolitan  Sewage  Discharge,  viz.  *  that  this  sewage 
manure  is  the  natural  substance  which  was  intended  to  manure  the  earth, 
and  that  the  earth  has  a  natural  liking  for  it,  independently  of  its  actual 
ammonia  or  phosphate  strength.' 

At  various  times  substances  which  act  as  deodorants  or  antiseptics  have 
been  used  in  combination  with  the  chemical  precipitants.  These  have  mostly 
met  with  failure,  partly  on  account  of  the  expense  involved  in  any  attempt 
to  deodorise  large  volumes  of  sewage  with  antiseptic  compounds  of  high 
price,  and  partly  owing  to  the  fact  that  the  antiseptic  substances  tended  to 
escape  with  the  effluent  water,  and  to  poison  the  fish  of  the  river  into  which 
it  was  discharged. 

The  most  successful  of  these  processes  appears  to  be  the  one  invented  by 
Hanson,  which  has  been  in  operation  at  Tottenham  and  Leyton.  At  these 
places  the  sewage  is  treated  with  lime  in  the  ordinary  v^^ay  and  with  black- 
ash  waste  (about  four  grains  to  the  gallon  of  sewage).  Crude  black-ash 
waste  is  a  refuse  of  alkali  works,  and  is  prepared  and  sold  in  London,  in 
a  granular  condition  suitable  for  mixing  with  sewage,  at  8L  IO5.  per  ton. 
This  substance  contains  about  30  per  cent,  of  the  sulphites  and  hyposulphites 
of  calcium,  which  are  powerful  reducing  or  deoxidising  agents,  and  impart  to 
the  waste  considerable  antiseptic  and  deodorising  properties.  They  are  not 
present  in  new  black-ash  waste,  but  are  formed  in  the  heaps  of  this  material 
which  have  been  long  exposed  to  the  air  by  the  oxidation  of  sulphide  of 
calcium.  Some  of  the  hyposulphite  of  calcium  passes  off  in  the  effluent, 
as  it  is  soluble  in  water.  The  adoption  of  the  process  at  Tottenham  and 
Leyton  was  followed  by  a  great  improvement  in  the  condition  of  the  river 
Lea,  which  had  been  very  much  polluted  with  sewage.  Besides  its  deodorant 
properties,  black-ash  waste  appears  to  prevent  the  formation  of  putrefactive 
bacterial  organisms  in  the  effluent,  but  it  does  not  interfere  with  the  growth 
of  those  microscopic  organisms  (infusoria,  anguilluhdge,  &c.)  which,  by  feed- 
ing on  organic  matters,  are  capable  of  purifying  foul  waters,  without  the 
production  of  foul  gases  from  putrefaction. 

Mr.  Dibdin,  chemist  to  the  late  Metropolitan  Board  of  Works,  recommended 
the  addition  of  manganate  of  sodium  and  sulphuric  acid  to  chemically  treated 
sewage.  These  substances,  when  used  together,  liberate  oxygen,  which  tends 
to  deodorise  the  sewage  ;  but  it  is  evident  that  the  amount  of  such  an  oxi- 
dising agent  which  would  be  required  must  be  very  large  to  produce  any 
appreciable  result,  and  so  the  expense  would  be  prohibitory. 

The  latest  of  these  deodorising  methods  is  that  known  as  the  Amines 
process,  which  has  been  tried  experimentally  at  the  Wimbledon  Sewage  Works 
and  at  Canning  Town.  The  sewage  is  treated  with  milk  of  lime  and  with  a 
small  quantity  of  herring-brine,  which  contains  a  certain  percentage  of  the 
compound  ammonia,  methylamine.  This  subtance  when  brought  into  con- 
tact with  lime  is  said  to  give  off  a  gas  termed  '  aminol,'  which  spreads  rapidly 
through  the  sewage,  and  is  a  powerful   antiseptic  and  deodorant.     When 

3  k2 


868  HYGIENE 

efficiently  carried  out,  the  process  is  said  to  effect  a  complete  sterilisatiou  of 
the  effluent,  all  micro-organisms  being  destroyed,  so  that  it  (the  effluent) 
imdergoes  no  secondary  fermentation  even  when  kept  at  a  high  temperature 
in  contact  with  the  air.  The  sludge,  too,  is  deodorised,  or  at  least  gives  off 
only  a  briny  smell,  as  well  as  the  effluent,  and  it  can  be  dried  in  pits  exposed 
to  the  air,  or  on  the  floor  of  a  drying  kiln,  without  giving  rise  to  any  nuisance. 
Such  being  the  case,  the  process  of  pressing  in  filter  presses  is  rendered 
unnecessary,  and  a  considerable  source  of  outlay  is  thereby  avoided.  It  will 
not  serve  any  useful  purpose  to  discuss  the  process  in  its  present  experi- 
mental stage,  but  it  may  be  observed  that  the  herring-brine  is  at  present  a 
cheap  commodity ;  and  it  is  evident  that  the  use  of  deodorants  and  anti- 
septics as  auxiliaries  to  precipitation  processes  must  be  advantageous  if  they 
retard  decomposition  without  interfering  with  oxidation  by  natural  agencies, 
and  without  injury  to  fish,  and  if  at  the  same  time  they  involve  but  little 
extra  cost. 

We  have  recently  had  an  opportunity  of  seeing  the  Amines  process  at 
work  at  the  Wimbledon  Sewage  Works  and  Farm.  As  recommended  by  the 
inventor  of  the  process,  the  quantity  of  cream  of  lime  used  is  very  large, 
viz.  about  seventy  grains  to  the  gallon.  The  lime  is  mixed  Avith  the  herring- 
brine  before  being  introduced  into  the  sewage.  With  this  large  quantity  of 
lime  the  precipitation  is  very  rapid,  and  after  the  clarified  effluent  is  run 
off'  from  the  tanks,  the  sludge  settled  at  the  bottom  may  again  be  used  as 
the  precipitation  agent,  no  chemicals  being  then  added  to  the  sewage.  As 
the  sewage  flows  into  the  tanks  it  stirs  up  the  sludge,  which  becomes  inti- 
mately mixed  with  it.  The  sludge  may  in  this  manner  be  used  several  times 
in  succession  before  it  is  needful  to  add  fresh  chemicals  to  the  sewage.  The 
sludge,  owing  to  the  large  quantity  of  lime  it  contains,  is  readily  pressed 
into  cakes  in  the  filter  presses,  and  these  cakes  are  sold  at  Wimbledon  at  the 
price  of  Is.  per  load  (ton).  The  moist  sludge  may  be  dried  in  pits,  without 
offence,  and  we  inspected  some  which  had  been  exposed  to  the  air  for  some 
months  in  a  pit,  without,  as  we  were  informed,  having  at  any  time  caused 
any  offence  in  the  process  of  drying. 

A  process  of  precipitating  sewage  by  electrolysis  has  been  tried  at 
Crossness  on  the  metropolitan  sewage,  and  also  at  Bradford,  in  Yorkshire,  in 
both  cases  merely  as  an  experiment.  The  system  is  the  invention  of  Mr. 
William  Webster.  The  process,  as  experimentally  tried  at  Bradford,  is 
described  by  Dr.  James  MacLintock,  Medical  Officer  of  Health  of  the  borough, 
in  a  paper  read  before  the  Public  Medicine  Section  of  the  British  Medical 
Association  Congress  at  Birmingham,  1890  ('  British  Medical  Journal,' 
Aug.  30,  1890).  There  is  a  very  large  proportion  of  manufacturing  refuse 
in  the  sewage  of  Bradford,  viz.  dyes,  acids,  alkalies,  grease,  and  other 
organic  matters  (wool  washings)  from  the  mills,  the  greater  majority  of  which 
are  engaged  in  the  woollen  industry.  The  large  proportion  of  mill  waste 
waters  in  the  sewage  renders  it  very  difficult  to  obtain  a  satisfactory 
effluent  with  the  lime  process  of  precipitation,  which  is  the  one  by  which  the 
bulk  of  the  sewage  at  Bradford  is  at  the  present  time  treated. 

The  description  of  the  electrical  process  is  thus  given  by  Dr.  Mac- 
Lintock : — 

'  The  plant  necessary  for  the  electrical  treatment  is  as  follows  : — (1)  An 
electrolytic  shoot  or  channel;  (2)  an  electric  generator;  (3)  motive  power 
for  generator ;  (4)  necessary  conductors  for  conveying  the  current  to  the 
shoot  from  the  generator ;  instruments  for  measuring  the  current  used  and 
the  potential  at  which  it  is  supphed.  The  electrolytic  shoot,  constructed  of 
brickwork,  is  25  feet  in  length,  24|  inches  wide,  and  4  feet  in  depth.     It  is 


THE  DISPOSAL   OF  BEFUSE 


869 


divided  into  eighteen  cells,  each  of  which  contains  twenty  iron  plates,  mea- 
suring 3  feet  X  1  ft.  2  in.  x  \  in.,  and  weighing  on  an  average  70  lbs.  each. 

'  These  plates  are  placed  vertically  in  the  shoot,  and  present  their  edges  to 
the  direction  of  flow  of  the  sewage.  The  cells  are  divided  one  from  the 
other  by  partitions  so  arranged  that  the  sewage  in  traversing  the  shoot 
passes  alternately  under  and  over  them.  Every  alternate  plate  is  connected 
respectively  with  the  positive  and  negative  poles  of  the  generator.  All  the 
plates  in  each  cell  are  connected  up  in  parallel,  and  the  cells  are  connected 
in  series  one  with  the  other.  The  generator  is  a  dynamo  by  Mather  and 
Piatt,  of  Manchester,  capable  of  developing  100  volts  and  180  amperes,  but 
for  this  plant  the  full  output  of  the  machine  is  not  required.  The  motive 
power  is  supplied  from  shafting  in  connection  with  a  steam  engine  belonging 
to  the  Corporation.  The  raw  sewage  first  enters  the  shoot,  and  passes  into 
a  settling  tank,  and  then  enters  another  shoot  similar  to  the  one  described, 
except  that  it  possesses  eight  cells  instead  of  eighteen,  and  from  there  flows 
rapidly  into  three  small  tanks,  and  thence  along  a  channel  into  the  stream. 
During  the  process  a  greasy  scum  collects  on  the  surface  of  the  tanks  and  on 
the  iron  plates  in  the  shoot.  This  is  collected  into  a  small  tank  partitioned 
off  for  the  purpose. 

'  It  is  at  once  seen  that  the  sewage  is  undergoing  a  change  during  its 
passage  along  the  electrolytic  shoot.  Gas  is  disengaged,  the  fluid  is  chang- 
ing colour  to  a  slight  degree,  assuming  a  greenish  hue  ;  and,  most  impor- 
tant of  all,  a  flocculent  precipitate  is  being  rapidly  formed.  In  the  first 
settling  tank  the  greater  part  of  this  precipitate  settles  as  sludge.  The 
rest  of  the  sewage  flows  into  the  second  shoot,  is  there  subjected  to  further 
electrical  treatment,  and  is  finally  allowed  to  flow  through  the  different 
tanks,  where  a  further  deposit  takes  place.  The  effluent  flows  into  a  channel 
where  it  is  still  further  aerated,  and  then,  as  before  stated,  into  the  Bradford 
Beck,  which  is  a  tributary  of  the  river  Aire.' 

The  active  precipitating  agent  formed  by  the  electric  current  appears  to 
be  hydrated  ferrous  oxide,  in  a  nascent  condition,  which  is  continuously 
being  formed,  and  is  used  as  fast  as  it  is  made.  The  arrangement  of  the 
plates  and  cells  insures  the  most  intimate  and  thorough  mixing  of  the  pre- 
cipitating agent  with  the  sewage.  The  continuous  formation  of  the  iron 
oxide,  its  nascent  condition,  and  the  thorough  mixing  of  it  with  the  sewage, 
are  the  special  features  of  the  process,  which  render  it  superior  (according  to 
the  results  hitherto  obtained)  to  the  ordinary  treatment  of  sewage  with  salts 
of  iron.  The  electrical  treatment  also  possesses  another  advantage  over  lime 
or  alumina  processes,  viz.  that  it  adds  very  little  to  the  sewage,  and  there- 
fore limits  the  quantity  of  sludge  to  the  lowest  amount  consistent  with  the 
removal  of  the  suspended  solids  from  the  sewage. 

The  composition  of  the  Bradford  sewage  before  the  electrical  treatment, 
and  of  the  effluent  after  it,  are  stated  by  Dr.  MacLintock  to  be — 


- 

Sewage  before 
Electrical  Treatment 

Effluent  after 
Electrical  Treatment 

Total  solids     .         .         .         .         . 
After  ignition  .         .         „         .         . 
Loss  on  ignition      .         »         .         . 

Chlorine 

Free  ammonia          .         ,         .         . 
Albuminoid  ammonia 

127  grs.  per  gal. 
69       „       „ 
58       „       „ 
10      „       „ 
32  parts  per  million 
15 

6*'i  grs.  per  gal. 
47       „       „ 
19       „       „ 

9       „       „ 
21  parts  per  million 

5 

From  the  fact  that  the  loss  of  solids  on  ignition  is  reduced  from  fifty- 
eight  to  nineteen  grains  per  gallon,  it  appears  that  nearly  70  per  cent,  of  the 


870  HYGIENE 

putrescible  portion  of  the  sewage  is  removed  by  the  treatment.  The  reduc- 
tion of  albuminoid  ammonia  is  also  very  considerable  (G6  per  cent.),  but  the 
free  ammonia  is  reduced  to  a  less  extent.  No  Hving  organisms  could  be 
detected  in  the  effluent,  although  the  sewage  was  crowded  with  bacteria, 
infusoria,  and  other  low  forms  of  organic  life. 

The  effluent  is  clear,  with  a  slight  yellowish-green  tinge,  and  is  little 
hable  to  undergo  secondary  putrefaction. 

We  may  conclude,  then,  that  the  experimental  trials  already  conducted 
show  that  the  process  is  capable  of  purifying  sewage,  and  even  sewage  of 
bad  quality,  in  a  higher  degree  than  can  be  attained  by  the  ordinary  methods 
of  precipitation  with  lime,  iron,  or  alumina ;  but,  on  the  other  hand,  the 
cost  of  the  process  will  probably  be  found  to  be  far  in  excess  of  that  required 
for  the  latter  methods.  A  large  initial  outlay  is  required  for  dynamos, 
steam  motive  power,  electrolytic  shoots,  iron  plates,  and  depositing  tanks. 
The  expense  of  working,  too,  must  be  high,  owing  to  the  consumption  of 
power,  whilst,  from  the  quantity  of  iron  present  in  the  sludge  and  effluent,  it 
is  evident  that  a  considerable  amount  of  iron  must  be  daily  consumed  and 
the  plates  will  require  frequent  renewal. 

To  sum  up,  then,  the  conclusions  at  which  we  may  arrive  with  regard  to 
precipitation  processes.  They  to  a  certain  extent  purify  the  sewage  by 
clarifying  it — that  is  to  say,  by  causing  a  deposition  of  the  suspended 
matters  in  the  settling  tanks — but  they  all  leave  a  very  large  amount  of 
putrescible  matter  in  the  effluent  water — namely,  all,  or  nearly  all,  the 
organic  matters  which  are  in  solution  in  the  seAvage,  and  fail  to  remove  any 
of  the  ammonia  contained  in  the  sewage,  which  invariably  escapes  in  the 
efflueut  water.  It  is  for  this  reason  that  the  manures  produced  from  the 
precipitated  sludge  are  of  so  inferior  a  character,  for  the  suspended  matters 
that  are  precipitated  from  sewage  constitute  less  than  one-sixth  of  the  value 
of  its  total  fertilising  ingredients.  Precipitation  processes,  then,  completely 
f;dl  to  utilise  sewage  to  any  advantage,  and  they  only  effect  a  partial  purifi- 
cation. On  the  other  hand,  when  employed  merely  as  a  preliminary  to  land 
treatment,  as  is  now  so  largely  the  practice,  they  are  capable  of  rendering 
services  of  great  value. 

Land  Filtration 

The  first  experiments  on  the  filtration  of  sewage  through  the  soil  were 
made  by  the  Elvers  Pollution  Commissioners  about  twenty  years  ago.  It 
was  then  shown  that  sewage  was  capable  of  being  very  efficiently  purified  in 
its  passage  through  a  few  feet  of  porous  soil,  but  that  to  secure  the  best 
results  the  filtration  must  be  from  above  downwards,  and  must  be  intermit- 
tent, in  order  that  the  pores  of  the  soil  may  be  aerated  during  the  periods  of 
rest.  The  process  of  upward  filtration  was  tried,  but  was  found  to  be  inef- 
ficient in  the  purification  of  sewage  from  soluble  offensive  matters. 

The  purification  of  sewage  by  soil  is,  to  a  certain  extent,  due  to  the  soil 
acting  as  a  mechanical  filter,  separating  and  retaining  the  suspended  matters- 
in -the  sewage.  But  the  principal  agent  is  the  oxidising  power  of  the  soil,, 
by  which  ammonia  and  organic  matters  in  the  sewage  are  converted  into 
nitrates,  nitrites,  and  carbonates.  This  oxidising  power  is  partly  dependent 
upon  the  porosity  of  the  soil,  by  which  the  particles  of  sewage  are  brought 
into  contact  with  oxygen  from  the  air  retained  in  its  pores,  but  chiefly  upon 
the  presence  of  nitrifying  organisms  belonging  to  the  family  of  bacteria.  These 
organisms  are  found  in  sewage  itself,  and  are  abmidantly  present  in  most 
soils,  but  chiefly  in  those  rich  surface  soils  of  mould  or  loam  which  contain 
an  abundance  of   organic  matters.     The    experiments    and  researches  of 


THE  DISPOSAL   OF  BEFUSE  871 

Schloesing,  Mxintz,  and  Warington  have  shown  that  these  nitrifying  organ- 
isms (one  of  which  has  been  isolated  by  Percy  Frankland)  feed  upon  the 
ammonia  and  organic  matters  of  sewage,  causing  their  oxidation,  and  that 
this  nitrification  is  confined  to  the  same  range  of  temperature  which  Kmits 
other  kinds  of  fermentation — that  is  to  say,  that  the  production  of  nitrates 
proceeds  very  slowly  near  the  freezing-point,  but  increases  in  rapidity  as  the 
temperature  rises,  reaching  its  maximum  of  energy  at  about  99°  F.  Other 
essentials  for  the  proper  performance  of  nitrification  are,  that  the  soil  be 
well  supplied  with  air — hence  the  advantages  of  porosity  in  the  soil  and  of 
intermittent  application  of  the  sewage — and  also  that  some  base,  such  as 
lime,  soda,  or  potash,  be  present  in  the  soil,  with  which  the  nitric  acid  as 
formed  may  combine.  Without  the  presence  of  this  salifiable  base  it  has 
been  found  that  nitrification  will  speedily  come  to  a  standstill. 

In  the  choice  of  a  soil,  then,  for  the  reception  and  purification  of  sewage 
the  following  conditions  should,  if  possible,  be  fulfilled :— The  soil  should  be 
of  a  rich  loamy  character,  and  therefore  well  supplied  with  the  nitrifying 
organisms.  It  should  be  porous  and  composed  of  small  fragments,  both  to 
allow  of  free  aeration  and  oxidation  and  also  so  that  it  may  present  an 
immense  surface,  covered  with  the  organisms,  to  the  sewage  while  percolating 
through  it.  Pure  sandy  soils  are  not  efficient  purifiers  until  their  particles 
have  become  coated  with  the  nitrifying  organisms  present  in  the  sewage,  and 
then  they  act  well.  All  retentive  soils  containing  an  excess  of  clay  must  be 
well  broken  up  and  mixed  with  town  ashes  or  with  ballast  (burnt  clay) ;  and  in 
such  cases  it  is  advisable  to  introduce  as  well  a  layer  of  alluvial  or  other  rich 
soil. 

The  surface  of  the  land  must  then  be  carefully  levelled,  to  admit  of  the 
sewage  flowing  evenly  over  every  part  of  it,  and  it  should  be  under-drained 
with  porous  agricultural  tile  drains  laid  at  a  distance  of  10  to  30  feet  apart, 
according  to  the  porosity  of  the  soil,  and  at  a  depth  of  4  or  5  feet  from  the 
surface.  To  lay  these  under-drains  at  a  greater  depth  from  the  surface  is 
now  thought  to  be  unnecessary,  as  the  nitrifying  organisms  are  not  usually 
found  at  a  greater  distance  from  the  surface  than  4  feet,  and  are  almost 
invariably  present  in  greatest  numbers  in  the  first  18  inches  of  soil.  The 
filtration  area  should  then  be  laid  out  in  plots,  each  plot  to  receive  sewage  for 
six  hours  only  every  day,  so  that  it  may  have  eighteen  hours  out  of  the 
twenty-four  for  necessary  rest  and  aeration. 

Where  the  sewage  of  a  large  number  of  people  has  to  be  applied  to  a  small 
area  of  land,  it  is  generally  advisable  to  precipitate  the  suspended  matters  of 
the  sewage  by  chemicals  as  a  preliminary  process,  and  to  irrigate  the  land 
with  the  clarified  sewage  effluent  only.  As  a  general  rule,  which,  however,, 
must  not  be  apphed  too  strictly,  it  may  be  stated  that  where  the  sewage 
of  more  than  1,000  people  must  be  applied  to  each  acre  of  land,  the  sewage 
should  undergo  a  preliminary  precipitation  ;  but  if  the  proportion  is  less  than 
1,000  to  an  acre  and  the  land  is  of  suitable  quality,  the  sewage  should  be 
allowed  to  flow  on  to  it  as  it  comes,  or  after  a  mere  simple  straining  to  remove 
the  larger  solid  bodies.  If  the  raw  sewage  is  applied  in  too  large  volumes 
to  a  smaU  area  of  land,  the  surface  of  the  soil  tends  to  become  rapidly  clogged 
with  a  thin  layer  of  suspended  matters  and  shme,  and  a  coating  is  formed 
which  prevents  the  percolation  of  the  sewage  and  the  penetration  of  air  into 
the  interstices  of  the  soil.  The  slimy  matters  in  sewage  are  derived  from 
the  grease  of  kitchen  waste  waters,  the  fats  of  soap,  the  mucus  from  the 
urinary  and  intestinal  mucous  membranes,  and  from  macerated  paper.  The 
land  has,  therefore,  to  be  constantly  raked  over,  and  the  surface  layers  dug 
up  and  incorporated  with  those  beneath  with  much  labour  and  expense ;  if 


-872  HYGIENE 

this  is  not  done  the  sewage  stagnates  and  forms  ponds  on  the  surface  and 
gives  rise  to  nuisance  as  soon  as  decomposition  commences. 

This  difficulty  is  entirely  avoided  by  irrigation  with  clarified  sewage  only. 
There  are  other  advantages  besides  this  in  adopting  precipitation  as  a 
preliminary.  Most  of  the  bacterial  organisms  and  their  spores,  the  active 
agents  in  putrefaction,  are  carried  down  in  the  precipitate,  and  therefore 
removed  from  the  eiikient,  which  is  consequently  less  prone  to  putrefy  and 
readier  to  undergo  nitrification  in  the  soil,  for  putrefaction  and  nitrification 
are  antagonistic  processes,  just  as  we  have  seen  putrefaction  and  oxidation  are. 
It  would  seem  that,  as  a  preliminary  to  land  treatment,  lime  is  the  best  pre- 
cipitating material  that  can  be  used,  as  it  introduces  into  the  sewage  effluent 
the  requisite  base  for  combination  with  the  nitric  and  nitrous  acids  formed  by 
nitrification.  Lime  is  also  the  best  material  to  neutralise  the  acids  and  acid 
salts  contained  in  sewage  which  has  received  the  waste  waters  of  manufactories 
and  chemical  works ;  this  kind  of  refuse  proving  a  great  hindrance  to  the 
purification  of  sewage  by  soil.  The  presence  of  antiseptics  in  the  sewage  also 
prevents  nitrification,  so  that  such  deodorising  agents  as  carbolic  acid  and 
perchloride  of  iron,  which  have  been  used  as  adjuncts  to  the  lime  process, 
must  not  be  employed  where  the  clarified  sewage  is  to  be  applied  to  land. 
Whether  black-ash  waste  or  herring-brine  are  sufficiently  strong  antiseptics 
to  prevent  nitrification  in  the  soil  has  not  yet  been  determined  ;  as  regards 
black-ash  waste,  we  should  be  inclined  to  think  that,  as  it  does  not  prevent 
oxidation  processes  and  the  growth  of  infusorial  life  in  the  effluent,  it  would 
not  either  have  any  prejudicial  effect  upon  the  nitrifying  process  in  the  soil. 

It  is  probable  that  by  intermittent  downward  filtration  through  well- 
drained  beds  of  porous  soil  of  suitable  nature,  the  clarified  sewage  of  as 
many  as  5,000  people  (100,000  to  150,000  gallons  daily)  may  be  applied  to 
each  acre  of  land  without  overdosing  the  soil  with  sewage  or  placing  too 
great  a  strain  upon  its  purifying  powers.  But  as  a  set-off  against  the  small 
area  of  land  required  to  cleanse  the  sewage  must  be  taken  into  account  the 
cost  of  precipitating  the  sewage  and  subsequently  dealing  with  the  sludge. 
And  it  is  even  now  doubtful  if  it  is  not  better  policy  for  a  local  authority  to 
acquire  a  larger  extent  of  land,  and  to  allow  the  suspended  matters  to  reach 
the  soil  by  gravitation  in  the  liquid  sewage,  rather  than  to  incur  the  cost  of 
separating  them  by  precipitation,  and  then  pumping  the  liquid  sludge  on  to 
the  land.  Mr.  Bailey  Denton  is  even  of  opinion  that,  if  properly  distributed 
on  carefully  prepared  surfaces,  sludge  on  land  generally  does  good  rather 
than  harm,  and  that  it  is  only  objectionable  when  mixed  with  trade  refuse. 
He  advises  filtration  beds  to  be  laid  out  in  ridges  and  furrows,  the  sewage 
being  allowed  to  flow  down  the  furrows,  whilst  vegetables  (cabbages,  roots, 
&c.)  are  grown  on  the  ridges.  The  sewage  obtains  access  to  the  roots  of  the 
vegetables,  which  assimilate  from  it  ammonia  and  organic  matters,  and  thus 
aid  the  purification.  The  leaves  and  stalks  being  above  the  sewage  are  not 
contaminated  by  floating  matters,  and  therefore  no  exception  can  be  taken 
to  their  use  as  articles  of  diet.  The  suspended  and  slimy  matters  of  the 
crude  sewage  are  deposited  in  the  furrows.  Before  they  have  had  time  to 
form  an  impenetrable  coating,  the  sewage  must  be  turned  off  the  plot,  and 
the  deposit  allowed  to  dry  and  shrink,  when  it  is  easily  broken  up  and 
incorporated  with  the  soil. 

When  intermittent  downward  filtration  is  properly  conducted  on  suitable 
land,  the  effluent  water  issuing  from  the  under-drains  is  found  to  be  very 
effectually  purified.  It  will  be  almost  entirely  deprived  of  organic  matters 
and  ammonia,  and  the  oxidation  to  which  these  have  been  subjected  will  be 
evidenced  by  the  presence  of  a  considerable  quantity  of  nitrates  in  the 


THE  DISPOSAL   OF  REFUSE  ^  873 

■effluent.  In  fact,  a  very  large  proportion  of  the  nitrogen  of  the  sewage  passes 
away  in  the  effluent  water  in  the  innocuous  form  of  nitrates  and  nitrites. 
The  chlorine,  however,  will  be  found  in  very  much  the  same  proportion  in 
the  effluent  as  in  the  sewage.  The  purification  is  usually  most  complete 
during  the  warmer  months  of  the  year,  when  the  nitrifying  organisms  are  at 
a  temperature  suitable  to  the  display  of  their  most  active  properties,  and 
when  vegetable  growth  is  at  a  maximum.  In  winter  the  purification  may 
be  less  complete,  but  not  necessarily  so,  as  the  oxidising  and  nitrifying  power 
of  a  soil  may  be  in  excess  of  the  work  provided  for  it,  so  that  even  with  a  low 
temperature  the  usual  amount  of  purification  may  be  attained. 

By  intermittent  downward  filtration  through  small  areas  of  land  we  see, 
then,  that  sewage  may  be  very  effectually  purified,  so  that  the  efiiuent  attains 
a  high  standard  of  cleanliness  and  is  admissible  into  streams  of  great  natural 
purity.  But  by  this  process  all  the  manurial  ingredients  of  the  sewage  are 
wasted,  except  in  those  cases  where  the  sale  of  vegetables  grown  on  ridges 
■  covers  part  of  the  cost  of  distribution  ;  and  even  in  these  cases,  as  nearly  all 
the  nitrogen  of  the  sewage  is  found  in  the  effluent  water,  but  little  can  be 
abstracted  for  the  growth  of  produce  or  for  the  enrichment  of  the  land 
The  area  of  land,  too,  being  so  very  limited,  the  amount  of  vegetable  produce, 
and  the  income  derived  from  its  sale,  must  necessarily  be  very  small.  In 
fact,  in  the  words  of  the  Eeport  of  the  Commission  on  Metropolitan  Sewage 
Discharge,  '  filtration  is  the  concentration  of  sewage  at  short  intervals  on  an 
■area  of  specially  chosen  porous  ground  as  small  as  will  absorb  and  cleanse 
it,  not  excluding  vegetation,  but  making  the  produce  of  secondary  im- 
portance.' 

The  cost  of  preparing  land  as  an  intermittent  filter  bed  is  much  greater 
than  that  required  for  broad  irrigation  on  the  usual  sewage  farm  plan  ;  but 
then  the  efficiency  of  each  acre  in  doing  the  work  of  purifying  sewage  is  far 
greater  by  the  former  method  than  by  the  latter.  Mr.  B.  Denton  estimates 
the  average  cost  of  preparing  land  for  a  filtration  area  at  about  101.  per 
acre. 

As  regards  liability  to  nuisance,  this  is  little  likely  to  arise  if  the  land  is 
properly  managed.  Where  crude  sewage  is  applied  to  the  soil,  offence  may  be 
caused,  as  previously  stated,  by  ponding  of  stagnant  sewage  owing  to  the  clog- 
ging of  the  surface  soil  with  slimy  matters.  Where  the  suspended  matters 
are  first  precipitated,  the  storage  of  sludge  on  the  premises  or  its  application 
to  land  in  a  liquid  state  may  give  rise  to  nuisance  ;  but  it  may  truly  be  said, 
with  regard  to  all  methods  of  dealing  with  such  foul  waste  matters  as  sewage, 
that  unless  ordinary  care  and  attention  are  bestowed  by  those  in  charge  the 
very  best  method  is  liable  to  fail  and  be  productive  of  niiisance,  and  therefore 
that  objections  raised  on  this  score  apply  less  to  the  principle  of  the  method 
pursued  than  to  the  manner  in  which  it  is  carried  out. 

Intermittent  downward  filtration,  preceded  by  a  precipitation  process  for 
"the  removal  of  the  suspended  matters,  was  the  method  recommended  by  the 
Commissioners  as  offering  the  best  solution  of  the  metropolitan  sewage 
discharge  difficulty.  The  enormous  quantity  of  precipitated  sludge  is  the 
chief  drawback  to  such  a  process,  but  the  Commissioners  thought  it  might 
be  got  rid  of  without  offence  by  burning  it,  carrying  it  out  to  sea,  digging 
it  into  land,  or  using  it  for  raising  low-lying  lands  at  the  mouth  of  the 
'  Thames. 

lEEIGATION 

Surface  or  broad  irrigation  was  defined  by  the  Eoyal  Commission  on 
"Metropolitan  Sewage  Discharge  to  mean  '  the  distribution  of  sewage  over  a 


874  HYGIENE 

large  surface  of  ordinary  agricultural  ground,  having  in  ^•iew  a  maximum 
growth  of  vegetation  (consistently  with  due  purification)  for  the  amount  of 
sewage  supplied.' 

We  have  already  seen  that  large  volumes  of  sewage  can  be  very  efficiently 
purified  by  filtration  through  small  areas  of  suitable  land  carefully  levelled 
and  under-drained  ;  but  that  although  the  purification  is  satisfactory,  the 
utilisation  of  the  manurial  ingredients  of  the  sewage  is  but  little  efl:ected,  as 
the  area  of  land  sewaged  is  too  small  to  raise  crops  in  any  quantity,  with  the 
result  that  the  nitrogen  of  the  sewage  to  a  large  extent  escapes  in  the  efduent 
water  in  the  form  of  nitrates.  If,  however,  the  same  volume  of  sewage  be 
applied  to  a  much  larger  area  of  land,  it  is  possible  to  utilise  the  sewage  by 
the  production  of  large  crops  of  grass  and  vegetables,  whilst  its  purification 
goes  on  as  before. 

It  is  e\'ident,  therefore,  that  a  sewage  farm  should  be  an  enlarged  filtration 
area.  The  same  forces  are  concerned  in  the  purification  of  the  sewage  as 
were  mentioned  under  land  filtration  ;  so  that  on  every  sewage  farm  the 
sewage  should  be  applied  intermittently  to  each  field  or  plot  of  land  ;  it  should 
then  sink  into  the  soil,  so  that  it  may  be  filtered  and  oxidised,  and  finally 
pass  away  by  means  of  under-drains  into  the  watercourse  which  efl'ects  the 
natural  drainage  of  the  locality.  Any  system  of  irrigation  by  which  the 
sewage  is  applied  too  continuously  to  the  land,  or  by  which  it  subsequently 
passes  over  the  surface  of  the  land  and  not  through  it,  is  likely  to  prove  a 
failure  by  giving  rise  to  nuisance  from  a  water-logged  condition  of  the  soil 
and  from  insufficient  purification  of  the  effluent. 

We  can  now  consider  the  conditions  under  which  sewage  farming  should 
be  conducted,  in  order  to  attain  a  successful  result  both  m  the  purification  of 
the  sewage  and  in  its  utihsation  as  a  manure. 

As  regards  the  position  of  the  farm  with  relation  to  the  town,  the  sewage 
of  which  is  to  be  applied  to  it,  it  is  most  important  that  the  land  should  lie 
at  such  a  level  that  the  sewage  may  flow  to  it  by  gravitation.  In  many 
instances,  however,  the  choice  of  land  in  the  vicinity  of  a  town  is  limited, 
and  recourse  has  to  be  had  to  pumping.  The  pumping  of  large  volumes  of 
sewage  on  to  a  sewage  farm  is  a  costly  process,  and  greatly  reduces,  or  even 
annihilates,  any  profits  that  would  otherwise  arise  from  the  sale  of  sewage- 
grown  produce  ;  there  is,  besides,  the  very  great  sanitary  disadvantage  that 
the  capacity  of  the  pumps  may  be  exceeded  at  times  when  the  volume  of 
sewage  is  very  large  from  admission  of  storm  waters  into  the  sewers,  and  if 
such  is  the  case  the  sewage  is  backed  up  in  the  outfall  and  tributary  sewers, 
leading  to  flooding  of  cellars  in  low-lying  districts  and  deposit  of  putrid 
sediment. 

To  make  sewage  farming  a  profitable  undertaking  it  is,  of  course,  neces- 
sary that  the  land  should  be  acquired  at  a  reasonable  price,  little,  if  any,  in 
excess  of  that  paid  for  ordinary  agricultural  ground  in  the  neighbourhood. 
In  very  few  instances,  however,  has  this  been  done.  Local  authorities  have 
experienced  the  greatest  difficulty  in  acquiring  land  for  sewage  irrigation,  and 
in  many  cases  have  given  enormous  prices  for  agricultural  land  required  for 
sewage  farms,  with  the  result  that  this  capital  expenditure,  added  to  enormous 
Parliamentary  and  legal  costs,  has  saddled  the  local  rates  with  burdens, 
which  for  very  many  years  cannot  possibly  be  diminished  to  any  appreciable 
extent  by  the  sale  of  sewage-gi'0T\m  produce.  Where  land  is  rented  for  sewage 
irrigation,  according  to  Mr.  Bailey  Denton,  21.  10s.  per  acre  is  a  price  which 
should  not  be  exceeded. 

The  nature  of  the  soil  of  a  proposed  farm  is  a  very  important  factor. 
Probably  the  best  kind  of  soil  is  a  porous  and  friable  loam  on  a  subsoil  of 


THE  DISPOSAL   OF  REFUSE  875 

gravel.  Such  a  soil  forms  a  very  efficient  filter  for  the  sewage  which  readily 
percolates  into  it,  and  it  involves  the  least  expenditure  in  under-drainage. 
Other  porous  soils  containing  considerable  admixtures  of  sand  and  gravel  are 
also  capable  of  purifying  and  utilising  sewage  when  properly  managed  ;  but 
dense  clayey  soils  should,  if  possible,  be  avoided,  as  unless  considerable 
expense  is  incurred  in  breaking  them  up  and  mixing  them  with  town  ashes, 
and  in  under-drainage,  they  prevent  the  percolation  of  sewage,  which  tends  to 
run  over  the  surface  and  to  gain  access  to  the  streams  in  a  very  insufficiently 
purified  condition,  especially  in  winter,  when  vegetation  is  least  active. 

The  extent  of  land  to  be  acquired  must  be  dependent  upon  a  variety  of 
circumstances,  such  as  the  cost  per  acre,  the  nature  of  the  soil,  the  variation 
in  the  volumes  of  sewage  between  dry  and  wet  weather  flow,  and  the  demands 
of  the  local  markets  for  the  grass  and  vegetables  produced  from  it.  Perhaps 
the  average  may  be  taken  as  one  acre  to  every  100  persons  of  the  population  ; 
but  it  must  be  clearly  understood  that  no  hard-and-fast  rule  can  be  laid 
down. 

The  amount  of  under-drainage  required  will  depend  partly  on  the  nature  of 
the  soil  and  partly  upon  the  extent  of  land  upon  which  sewage  can  be  applied 
in  relation  to  the  whole  volume  of  sewage  reaching  the  farm.  Least  under- 
drainage  will  be  required  for  the  lighter  kinds  of  soil  resting  upon  a  porous 
subsoil,  and  where  the  area  of  land  is  large  in  proportion  to  the  volume  of 
sewage.  For  soils  of  medium  consistence,  or  where  the  area  of  land  to  which 
sewage  is  applicable  is  relatively  small,  under-drainage  must  be  thoroughly 
carried  out — pipes  of  porous  earthenware  2  inches  in  diameter  being  laid 
at  a  depth  of  from  4  to  6  feet  from  the  surface  of  the  soil,  and  in  parallel  lines 
from  20  to  100  feet  apart,  according  to  circumstances.  These  subsidiary 
drains  should  eventually  be  connected  at  suitable  points  with  arterial  drains 
of  larger  size  which  join  the  main  effluent  drain  or  channel  that  discharges 
into  the  stream  at  the  lowest  part  of  the  farm. 

The  outfall  sewer  should  conduct  the  sewage  to  the  highest  point  of  the 
farm,  at  which  spot,  before  the  sewage  is  allowed  to  flow  over  the  land,  it  is 
generally  advisable  to  screen  it  through  a  grid  to  remove  the  larger  solid 
matters.  From  this  point  the  land  should  fall  away  gently,  so  that  the 
sewage  may  reach  every  part  of  the  farm  by  gravitation.  Certain  portions  of 
the  land  may,  however,  require  levelling,  to  ensure  the  regular  and  even 
irrigation  which  is  desirable.  The  main  carriers  for  the  distribution  of  the 
sewage  should  be  constructed  of  masonry  or  concrete,  in  the  form  of  open 
channels,  which  are  easily  flushed  and  cleansed ;  or  stoneware  channel  pipes 
may  be  used.  The  subsidiary  carriers  need  be  nothing  more  than  grips  dug 
in  the  land,  which  can  be  filled  in  as  soon  as  they  become  to  any  extent 
clogged  with  suspended  slimy  matters,  and  fresh  ones  dug  in  their  place. 

For  applying  the  sewage  from  the  main  carriers  to  the  surface  of  the 
land,  the  best  plan,  as  a  general  rule,  to  adopt  is  that  known  as  the  ridge 
,  and  furroio  system.  The  surface  of  the  ground  is  laid  out  in  broad  ridges 
'  — 30  to  70  or  more  feet  across — running  parallel  to  each  other,  but  at 
right  angles  to  the  main  carrier,  from  which  they  fall  away  to  a  slight 
extent.  Between  every  two  ridges  is  a  longitudinal  furrow  formed  by  the 
slope  of  the  ridges  towards  each  other.  The  furrow  is  some  few  inches 
(eight  or  ten)  below  the  level  of  the  centres  of  the  ridges  on  each  side  of  it. 
The  sewage  is  applied  as  follows  :  A  workman  stops  the  flow  of  sewage  in  a 
main  carrier  by  lowering  a  sluice,  or  placing  a  '  stop  '  of  wood  athwart  the 
carrier,  opposite  the  centre  of  a  ridge.  The  sewage  then  overflows  from  the 
main  carrier  and  passes  down  a  grip  in  the  centre  of  the  ridge,  from  which 
it  can  be  made  to  flow  over  the  sides  of  the  ridge  towards  the  furrow  by 


876  HYGIENE 

throwing  some  earth  into  the  central  grip  or  by  blocking  the  passage  with  a 
board.  After  a  certain  interval  the  sewage  is  allowed  to  flow  a  little  further 
down  the  central  grip,  and  then  again  made  to  overflow  as  before,  mitil  the 
whole  area  of  land  has  received  its  allotted  portion  of  sewage. 

The  catchicatcr  system  has  been  adopted  at  farms,  such  as  that  at 
Warwick,  where  the  ground  has  a  very  considerable  slope  from  the  point  of 
delivery  of  the  sewage.  The  main  carriers  are  carried  across  the  direction 
of  the  slope  along  contour  lines,  so  as  to  be  more  or  less  parallel  to  each 
other  one  above  the  other,  and  the  sewage,  as  it  overflows  from  the  highest 
carrier,  passes  over  the  land  below,  such  of  it  as  is  not  absorbed  reaching  the 
carrier  next  below  and  again  overflowing,  and  so  on  to  the  lowest  carrier. 
The  disadvantage  of  this  system  is  that  the  higher  portion  of  the  land  receives 
too  much  sewage  and  the  lower  gets  little  else  than  water. 

Yet  another  plan  is  that  known  as  the  pane  and  gutter  system,  which  is 
in  use  at  the  Croydon  Sewage  Farm,  where  there  is  a  general  very  slight  fall 
of  the  land.  It  is  very  similar  to  the  catchwater  system,  the  sewage  passing 
from  the  main  carriers  laid  across  the  fields,  and  spreading  over  the  surface 
of  the  beds  from  above  downwards.  At  the  Croydon  Farm  the  soil  is  rather 
retentive,  so  that  there  is  a  tendency  for  the  sewage  to  have  a  surface  flow 
only,  without  any  large  amount  of  percolation,  and  to  be  carried  from  one  field 
to  another  imtil  it  passes  away  into  the  brook,  with  only  such  an  amount  of 
purification  as  is  brought  about  by  its  exposure  to  the  air  and  by  the 
action  of  vegetation.  It  may  be  stated,  however,  that  the  sewage  is  very 
fairly  purified  at  the  Croydon  Farm,  at  any  rate  in  summer,  by  surface 
flow,  and  the  efiluent  flows  into  the  stream  in  a  clear  and  colourless  condi- 
tion. The  area  of  land  available  for  irrigation  is  500  acres,  and  as  the  popu- 
lation contributing  the  sewage  is  100,000,  the  sewage  is  not  applied  in  a 
larger  proportion  than  about  200  persons  for  each  acre.  The  sewage,  too, 
is  freed  from  its  coarser  solid  bodies  by  means  of  a  Latham's  extractor  before 
being  used  for  irrigation,  and  this  helps  to  prevent  the  deposit  of  foul  sedi- 
ment on  the  carriers  and  on  the  surface  of  the  land. 

One  of  the  greatest  difficulties  connected  with  sewage  farming  is  the 
necessity  of  dealing  with  the  enormous  volumes  of  dilute  sewage  brought  to 
the  farm  by  the  drain-sewers  of  the  combined  system  during  and  after  periods 
of  heavy  rainfall.  At  such  times  it  is  often  inadvisable  to  apply  the  sewage 
to  land  on  which  crops  are  being  grown,  which  may  already  be  sodden  with 
moisture,  and  the  area  of  fallow  land  may  be  insufficient  to  deal  with  the 
large  quantities  of  dilute  sewage  that  would  have  to  be  applied  to  it.  An 
obvious  method  of  getting  over  the  ditficulty  is  to  relieve  the  sewers  by  means 
of  a  storm  overflow  direct  into  the  river.  In  doing  this  it  may  be  contended 
that  the  sewage  is  so  excessively  dilute  that  no  harm  is  likely  to  arise  from 
its  being  allowed  to  enter  the  river  ;  yet,  on  the  other  hand,  it  must  not  be 
forgotten  that  the  same  amount  of  sewage  would  still  enter  the  river,  although 
with  a  larger  body  of  water,  that  the  manurial  ingredients  of  the  sewage  so 
discharged  will  be  wasted,  and  that  in  towns  where  accumulation  takes 
place  in  the  sewers  on  account  of  their  faulty  construction  or  of  want  of 
regular  flushing,  the  sewage  so  escaping  is  actually  very  much  stronger  than 
it  is  in  ordinary  times  ;  and  besides  there  is  always  the  danger  of  the  poisons 
of  enteric  fever  and  other  diseases  being  discharged  into  water  which  may  be 
used  by  towns  lower  down  for  domestic  purposes. 

Another  and  less  objectionable  method  is  that  recommended  by  Mr. 
Bailey  Denton  of  connecting  the  storm  overflow  with  osier  beds  laid  out  in 
ridges  and  furrows,  the  osiers  growing  on  the  ridges.  On  reaching  these 
beds  the  flow  ol  sewage  is  checked,  and  this  causes  the  deposit  of  the  floating 


THE  DISPOSAL   OF  BEFUSE  %11 

solid  matters  in  the  furrows,  wliilst  the  flood  water  rises  and  overflows  the 
ridges  and  the  osiers  growing  on  them.  These  beds  need  not  be  under- 
drained,  as  they  are  only  required  to  clarify  the  sewage,  which  without  tlie 
check  afforded  by  them  would  be  impetuously  discharged,  together  with  all 
its  floating  matters,  into  the  river.  Osier  roots  also  tend  to  grow  down  in 
long  filaments,  which  on  reaching  the  undcr-drains  might  find  their  way  in- 
side and  block  the  pipes.  Meadow  land  on  the  banks  of  a  river  has  been 
used  for  the  same  purpose,  but  it  would  seem  that  osier  beds  are  preferable, 
as  they  more  perfectly  clarify  the  sewage. 

An  even  better  plan  is  to  set  apart  a  portion  of  the  farm  where  the  land 
is  most  porous  as  a  filter  bed,  specially  prepared  and  closely  under-drained 
six  feet  deep.  The  land  may  be  left  fallow,  or  laid  out  in  ridges  and  furrows 
and  cropped  with  vegetables.  The  filter  bed  should  be  subdivided  into  plots 
for  the  intermittent  application  of  the  sewage,  and  should  be  of  extent  suf- 
ficient to  purify  the  whole  of  the  sewage  by  intermittent  downward  filtration, 
when  from  any  reason,  such  as  excessive  dilution,  it  is  inadvisable  to  apply 
the  sewage  to  the  general  surface  of  the  farm.  Such  a  filter  bed  would,  of 
course,  add  somewhat  to  the  expense  incurred  in  the  original  construction  of 
the  farm,  but  its  great  utility  would  far  more  than  counterbalance  its  cost, 
as  on  all  farms,  even  where  storm  and  subsoil  waters  are  excluded  from  the 
sewers,  sewage  irrigation  of  land  where  crops  are  growing  is  often  attended 
with  considerable  risk  of  injury  to  the  plants.  The  result  is  that  on  sewage 
farms,  as  usually  conducted,  the  choice  of  crops  is  limited  to  such  as  are  not 
injured  by  the  continual  apphcation  of  sewage,  and  these  being  produced 
in  excessive  quantity  often  exceed  the  demands  of  the  local  markets,  and  are 
consequently  almost  worthless.  If  every  farm  had  a  filter  bed  of  sufficient 
area  to  cleanse  all  the  sewage  when  not  required  for  irrigation,  a  variety  of 
produce  could  be  grown  under  the  most  favourable  conditions,  and  the  kind 
and  quantity  of  each  crop  could  be  regulated,  as  in  ordinary  farming,  accord- 
ing to  the  demand  for  it  and  the  chance  of  reaping  a  fair  profit  by  its 
sale. 

There  can  be  no  question  that,  as  a  general  rule,  the  sewage  would  be 
more  valuable  to  the  sewage  farmer  if  rain  and  subsoil  water  were  kept  out 
of  it,  as  the  farm  would  then  not  be  liable  to  those  sudden  inundations  vnth 
enormous  volumes  of  weak  sewage  which  tax  the  resources  of  the  management 
to  their  utmost  in  their  efforts  to  deal  with  it.  But  if  this  were  done,  there 
is  the  danger  of  the  sewage  proving  too  strong  for  the  crops  and  requiring 
dilution,  which  is  especially  likely  to  be  the  case  if  the  water  supply  of  the 
town  is  inadequate  to  the  requirements  of  the  population.  In  such  cases  it 
would  be  advisable  to  have  at  hand  some  means  of  diluting  the  sewage  before 
its  arrival  at  the  farm,  and  this  might  possibly  be  effected  by  turning  the 
water  of  the  subsoil  drains  into  the  sewers.  At  Breton's  Farm  at  Eomford 
during  very  dry  seasons  it  has  even  been  found  necessary  to  return  the  pure 
effluent  water  into  the  tanks  and  mix  it  with  the  sewage  before  applying  the 
latter  to  the  ground  in  order  to  ensure  the  requisite  dilution. 

There  is  still  another  difficulty  which  remains  to  be  discussed — namely, 
that  which  is  supposed  to  arise  during  severe  frosts.  But  too  much  stress 
has  been  laid  upon  this  ;  and  as  a  matter  of  fact  sewage  irrigation  continues 
uninterruptedly  during  the  coldest  weather.  It  is  true  that  a  coating  of  ice  is 
formed  over  the  surface  of  the  farm,  but  the  sewage,  which  never  has  a  tem- 
perature below  45°  F.,  flows  underneath  this  coating  and  sinks  into  the  soil, 
which  remains  quite  unfrozen  and  open.  As  soon  as  the  weather  begins  to 
moderate,  the  sewage  rapidly  melts  the  ice  above  it.  This  is  not  only  the  case 
in  this  country,  but  in  Germany  and  America,  where  the  winter  cold  is  far  more 


B78  HYGIENE 

intense.  Thus  at  Pullman,  U.S.A.,  a  visit  paid  to  the  sewage  farm  inFebruary, 
1885,  showed  that,  although  for  five  days  previously  the  temperature  had  not 
risen  to  0°  F.,  and  had  been  as  low  as  —25°,  the  sewage  was  going  on  to  the 
land,  but  covered  by  a  stratum  of  ice  from  1  to  8  mches  thick.  On  breaking 
the  ice  and  digging  a  hole  in  the  groimd  below  with  a  spade,  the  soil  was 
seen  to  be  unfrozen  and  perfectly  open.  As  the  weather  moderated  the 
sewage  rapidly  melted  the  ice  above  it.' 

Wecome  now  to  the  consideration  of  the  crops  that  are  best  suited  for  sewage 
irrigation,  and  from  the  growth  of  which  it  is  most  reasonable  to  expect  to 
derive  a  profit.  A  committee  of  the  Local  Government  Board  on  Modes  of 
Treating  To-ftTi  Sewage  reported  as  long  ago  as  1876  that  Italian  rye-grass  is 
probably  in  all  respects  the  most  advantageous  crop  to  be  grown  under  sewage. 
Subsequent  experience  has,  we  think,  fully  confirmed  the  favourable  opinion 
of  the  committee,  and  Italian  rye-grass  is  now,  as  then,  the  staple  product  of 
most  sewage  farms.  Its  advantages  were  stated  by  the  committee  to  be  as 
foUows :  '  It  is  capable  of  absorbing  a  larger  volume  of  sewage  than  any 
other  crop.  It  occupies  the  soil  so  as  to  choke  down  weeds,  comes  early 
into  the  market  in  spring,  continues  through  the  summer  and  autumn, 
bearing  from  five  to  as  many  as  seven  cuttings  in  the  year,  and  producing 
from  thirty  to  fifty  tons  of  wholesome  grass  upon  each  acre.' 

It  is  certainly  the  fact  that  plots  of  rye-grass  may  be  almost  continuously 
treated  with  enormous  volumes  of  sewage,  not  only  without  injury,  but  even 
with  benefit  to  their  growth.  Dr.  Alfred  Carpenter  has  stated  his  belief  that 
this  plant  possesses  the  power  of  absorbing  and  assimilating  the  organic 
matters  of  sewage  directly,  unlike  plant  life  in  general,  for  which  complex 
organic  bodies  must  be  reduced  to  such  simple  constituents  as  ammonia, 
nitrates,  and  phosphates  before  they  can  be  assimilated.  However  this  may 
be,  there  can  be  no  doubt  that  Italian  rye-grass  flourishes  under  a  treatment 
with  sewage  which  would  kill  most  other  plants,  and  that  it  at  the  same 
time  very  materially  aids  in  the  cleansing  of  the  sewage  with  which  it  is 
irrigated. 

Although  this  is  the  case,  the  area  of  land  placed  under  this  crop  must 
have  some  reference  to  local  means  of  consumption,  or  the  crop,  or  a  part 
of  it,  may  be  wasted.  For  the  grass  when  cut  will  neither  keep  nor  bear  long 
carriage,  and  although  in  a  warm  and  dry  summer  good  hay  may  be  made 
from  it,  or  ensilage  in  a  wet  season,  where  silos  are  at  hand,  still  it  is  diffi- 
cult to  dispose  of  such  fodder  at  a  profit,  owing  to  cost  of  carriage.  Practical 
experience  has  shown  that  the  rye-grass  is  turned  to  its  most  profitable  use 
when  used  for  feeding  milch  cows  or  rearing  stock.  It  therefore  follows 
that,  should  the  acreage  of  the  sewage  farm  justify  the  experiment,  a  stock 
and  dairy  farm  ought  to  be  associated  with  it.  This  experiment  has  been 
carried  to  a  very  successful  result  at  Birmingham.  At  first  there  is  gene- 
rally a  certain  prejudice  to  be  overcome  on  the  part  of  the  consumers  in  the 
neighbourhood  agamst  sewage-grown  produce  and  the  milk  and  meat  from 
animals  fed  off  it.  But  this  sentiment  quickly  wears  away  for  want  of 
any  reasonable  basis.  For,  as  we  shall  presently  have  occasion  to  show,  not 
only  is  sewage-grown  produce  neither  dropsical  nor  prone  to  decomposition, 
but  evidence  is  entirely  wanting  to  prove  that  its  consumption  has  at  any 
time  caused  disease.  The  meat  and  milk  also  of  animals  reared  and  kept 
on  sewage  farms  in  no  way  differs  from  the  milk  and  meat  x^roduced  on 
ordinary  farms.     We  see,  then,  that  Italian  rye-grass  is  likely  to  be  a  profit- 

'  Beport  of  the  Mystic,  Blackstone,  and  Charles  Rivers  Draiymge  Commission,  Mass., 
U.S.A.,  188f5. 


THE  DISPOSAL   OF  BEFUSE  879 

able  crop  if  it  can  be  converted  into  milk,  butter,  and  meat,  and  that,  under 
such  circumstances,  it  can  be  cultivated  in  large  quantities,  but  that  on 
farms  where  livestock  is  not  kept  it  may  on  occasion  prove  a  drug  in  the 
market,  and  have  to  be  given  away. 

After  three  years  the  plot  of  rye-grass  should  be  ploughed  up,  and  the 
land  sown  with  cabbages,  swedes,  or  mangolds.  For  these,  as  for  nearly  all 
other  crops  grown  on  sewaged  land,  yearly  rotation  is  the  best.  Cabbage 
and  mangold  wurzel  were  considered  by  the  Local  Government  Board  Com- 
mittee to  be  the  only  farm  crops,  besides  Italian  rye-grass,  that  persistently 
flourish  upon  any  soils,  heavy  or  light,  under  continual  doses  of  town 
sewage.  And  even  these  should  only  be  sewaged  when  growing,  and  not  when 
they  have  arrived  at  maturity.  They  no  doubt  help  to  exhaust  the  soil  of 
the  sewage  matters  retained  in  it,  which  have  not  been  absorbed  by  the  rye- 
grass. The  same  committee  also  stated  that  no  growing  crop,  save  natural 
grass,  should  be  sewaged  during  the  depth  of  winter  ;  and  for  potatoes, 
turnips,  most  vegetables,  and  certainly  for  all  pulse  and  cereals,  the  land 
ought  rather  to  be  enriched  by  frequent  irrigation  in  the  preceding  season 
than  treated  with  sewage  when  these  crops  are  growing,  except  in  times  of 
great  drought,  and  even  then  care  is  requisite.  There  can  be  no  question 
that  fallow  land  is  enriched  by  irrigation  with  sewage  from  retention  in  the 
soil  of  some  of  its  manurial  ingredients,  just  as  when  solid  manures  are 
applied. 

From  what  has  gone  before,  it  will  be  evident  that  unless  a  sewage  farm 
is  provided  with  a  special  filtration  area  to  dispose  of  the  sewage  when  not 
required  for  the  fertilisation  of  the  land,  or  unless  the  area  of  land  is  con- 
siderably in  excess  of  that  necessary  for  cleansing  the  sewage,  the  crops  are 
practically  limited  to  the  three  that  are  not  injuriously  affected  by  sewage 
irrigation  when  in  growth,  viz.  Italian  rye-grass,  cabbages,  and  mangolds, 
in  addition  to  natural  meadow  grass  and  osiers.  On  such  farms,  therefore, 
it  would  be  useless  to  look  for  a  profit  from  the  sale  of  produce.  But  on 
the  farms  where  a  special  filtration  area  is  provided,  or  that  have  a  large 
acreage  for  the  volume  of  sewage,  not  only  can  numerous  other  crops  be 
grown  with  little  risk  of  their  being  spoilt  by  the  enforced  application  of 
sewage,  but  market  gardening  even  may  be  undertaken  and  made  very 
profitable.  Italian  rye- grass,  however,  from  the  peculiar  conditions  under 
which  only  can  sewage  farming  be  undertaken — viz.  the  necessity  to  purify 
the  sewage  night  and  day,  Sunday  and  week-day,  wet  weather  or  fine 
— must  always  be  the  staple  crop,  and,  as  we  before  said,  it  can  only 
be  profitably  utilised  by  employing  it  as  fodder  for  livestock  on  the  farm 
itself.   . 

The  amount  of  capital  required  to  stock  and  work  a  sewage  farm  is 
very  greatly  in  excess  of  that  required  for  an  ordinary  farm  on  the  same 
kind  of  soil.  The  Local  Government  Board  Committee  stated  that  five 
times  the  usual  amount  of  money  would  be  needed  for  a  sewage  farm  upon 
which  most  of  the  produce  is  consumed.  There  is  a  far  larger  amount  of 
labour  required  to  keep  the  land  clean  and  free  from  the  weeds  which  the 
sewage  tends  to  foster,  and  to  take  off  the  land  the  enormous  crops  of 
grass  and  roots  that  are  grown.  But  against  this  must,  of  course,  be  set  the 
increased  value  of  the  crops  over  those  of  an  ordinary  farm. 

We  come  now  to  the  consideration  of  the  manurial  value  of  the  sewage 
and  to  the  practical  results  that  can  be  obtained  by  its  use.  We  have 
already  stated  briefly  the  conditions  under  which  sewage  farming  may  be 
undertaken  with  some  prospect  of  success,  and  we  shall  suppose  that  these 
conditions  have  been  either  totally  or  in  large  part  complied  with.     It  ia 


880  HYGIENE 

now  pretty  "well  known  that  sewage  farms  are  not  always  or  necessarily  a 
success,  either  in  purifying  or  utilising  the  sewage  ;  and  to  establish  a  farm 
on  heavy  clay  soil,  without  sufficient  land  or  witliout  the  other  essential 
elements  previously  alluded  to,  is  merely  to  court  defeat  in  one  or  both  par- 
ticulars, and  most  probably  in  both. 

The  water  of  the  sewage  is  a  great  difficulty,  where  no  precautions  have 
been  taken  to  deal  with  excessive  quantities  of  it ;  but  where  these  have 
been  taken  the  water  has  its  uses,  which  counterbalance  its  di-awbacks.  It 
enables  the  sewage  farmer  to  be  independent  of  drought  in  dry  seasons 
and  to  rear  large  crops  of  meadow  and  rye-grass,  roots,  and  cabbages,  for 
the  growth  and  maintenance  of  which  moisture  is  so  essential.  In  the 
parched-up  land  around  the  sewage  farm  during  a  period  of  drought  these 
crops  are  failures,  and  consequently  the  sewage-grown  crops  are  enormous 
comparatively  in  volume,  and  command  a  correspondingly  high  price  in  the 
market.  Then,  again,  the  water  is  the  vehicle  for  ammonia  and  organic 
matters  in  solution  ;  and  such  fertilising  matters  are  more  readily  absorbed 
by  the  roots  of  plants  when  in  solution  in  water  than  in  any  form  of  solid 
manure.  The  water  of  the  sewage,  then,  is  of  use  as  a  fertilising  agent,, 
as  well  as  a.  vehicle  for  the  manurial  matters  which  it  carries  with  it. 

As  regards  these  manurial  matters  of  the  sewage,  we  have  seen  what 
they  are  worth  theoretically  in  a  ton  of  sewage  both  in  the  form  of  matters 
in  suspension  and  matters  in  solution  (see  p.  850).  What  they  are  worth 
practically  is  shown  by  the  statistics  of  the  crops  raised  on  sewage  farms, 
and  by  a  comparison  of  these  statistics  with  those  derived  from  farms  on  the 
same  kind  of  soil  where  sewage  is  not  applied.  It  is  not  possible  in  thi& 
article  to  examine  these  figures,  but  the  general  result  may  be  stated  to  be 
that  such  crops  as  thrive  under  sewage  are  produced  in  far  larger  quantities 
on  sewage  farms  than  on  the  ordinary  farms  of  the  neighbourhood,  and  are 
obtained  very  much  earlier  in  the  spring  season,  no  doubt  from  the  warmth 
of  the  sewage  keeping  up  the  temperature  of  the  soil  throughout  the  cold  of 
winter.  What  the  value  of  such  crops  may  be  has  been  already  the  subject 
of  consideration  ;  but  it  must  also  be  remembered  that  fallow  land  is  enriched 
by  the  application  of  sewage,  and  that  where  this  is  done  in  the  season  pre- 
ceding the  raising  of  pulse,  cereals,  or  vegetables,  it  is  not  necessary  to  apply 
solid  manures  as  well,  so  that  a  very  considerable  source  of  expense  is  saved 
to  the  farmer.  It  may  indeed  be  stated  generally  that  sewage  contains  every 
fertilising  ingredient  required  by  any  soil,  so  that  artificial  or  foreign 
manures  can  be  entirely  dispensed  with  on  a  sewage  farm.  If  this  were  not 
the  case  it  would  have  been  impossible  to  obtain  any  produce  from  those 
plots  of  barren  sea  sand  irrigated  with  sewage,  of  which  the  Craigentinny 
Meadows,  near  Edinburgh,  and  the  Dantzig  Sewage  Farm  are  such  striking 
examples.  At  Craigentinny  enormous  crops  of  Italian  rye-grass  are  produced,, 
whilst  at  Dantzig  the  farm  has  been  productive  of  excellent  crops  of  grasses, 
roots,  and  cereals.  The  latter,  indeed,  appear  to  thrive  well  on  this  very 
porous  soil  when  treated  with  large  doses  of  sewage.  It  is  said  to  be  a  truly 
curious  sight  here  to  see,  surrounded  by  irregular  dunes  of  blowing  sea-sand,, 
vast  spaces  covered  with  a  vigorous  vegetation  as  a  result  of  the  application 
of  the  sewage,  which  were  formerly  as  barren  as  the  surrounding  sand-hills. 
As  another  example,  we  may  mention  the  Plain  of  Gennevilliers,  near  Paris, 
where  a  barren  and  unfruitful  waste  has  been  turned  by  means  of  sewage 
irrigation  into  a  vast  garden,  400  acres  in  extent,  producing  flowers,  fruit,  and 
a  large  variety  of  crops  for  the  Paris  market.  ('  Les  Travaux  d'Assainisse- 
ment  de  Dantzig,  Berlin,  Breslau,'  par  M.  Durand-Claye.) 

The  value  of  sewage  is  indeed,  after  all,  to  a  large  extent  a  question  of 


THE  DISPOSAL   OF  BEFUSE  881 

soil.  On  rich  lands,  which  are  often  of  a  retentive  nature,  the  advantage 
of  further  enriching  the  soil  with  the  manurial  matters  of  the  sewage  is  often 
more  than  counterbalanced  by  oversaturation  of  the  land  with  water.  On 
poor  and  barren  soils,  however,  which  are  moreover  usually  highly  permeable 
to  water,  the  sewage  introduces  the  fertilisers  which  are  naturally  absent,  and 
without  which  no  crops  can  grow  ;  whilst  the  excess  of  water  rapidly  perco- 
lates down  to  the  subsoil,  leaving  the  top  soil  in  the  most  favourable  condi- 
tion for  the  growth  of  plant  life.  The  value  of  the  land,  as  at  Craigentinny 
and  Dantzig,  is  enormously  increased,  and  what  was  before  a  barren  waste 
becomes  land  capable  of  cultivation  and  of  producing  crops  of  large  value. 
Here,  then,  we  see  sewage  utilised  to  the  best  advantage,  and  a  noxious  waste 
product  converted  into  a  valuable  source  of  food  supply. 

Having  endeavoured  to  make  it  apparent  that  sewage  is  under  certain 
conditions  and  circumstances  a  fertiliser  of  the  soil  of  the  greatest  practical 
value,  we  can  now  turn  to  certain  experiments  which  have  been  made  with 
the  view  of  estimating  the  amount  of  nitrogen  recovered  in  the  crops  of  a 
sewage  farm  from  the  sewage  applied  to  the  soil. 

These  experiments  were  conducted  by  the  Committee  of  the  British 
Association  on  the  Treatment  and  Utilisation  of  Sewage,  and  were  made  upon 
Breton's  Sewage  Farm,  near  Eomford,  extending  over  a  period  of  five  years 
(1871-6).  The  committee  ascertained  that  the  amount  of  nitrogen  recovered 
in  the  crops  during  the  whole  of  this  period  was  equal  to  32-88  per  cent,  of 
the  amount  applied  in  the  sewage  to  the  surface  of  the  soil,  and  that  the 
amount  recovered  per  acre  of  the  farm  under  crop  averaged  182  lbs.  annually. 
As  was  to  be  expected,  the  committee  found  considerable  annual  variations 
in  the  percentage  of  nitrogen  recovered,  these  variations  being  dependent 
upon  changes  in  local  circumstances.  About  11  per  cent,  of  the  total 
nitrogen  applied  to  the  land  escaped  in  the  effluent  water,  but  of  that  only  a 
fractional  percentage  was  in  an  organic  form,  the  largest  proportion  existing 
in  the  oxidised  form  of  nitrates.  About  56  per  cent,  of  the  nitrogen  applied 
in  the  sewage  is  unaccounted  for,  but  of  this  a  portion  must  have  been 
retained  in  the  soil  of  the  farm,  which  it  served  to  enrich.  For  it  was  found 
on  comparing  the  analysis  of  the  average  composition  of  the  soil  of  the  farm, 
made  previously  to  the  application  of  sewage,  with  a  similar  analysis  made 
in  1878  that  the  phosphoric  acid  in  the  soil  was  increased  nearly  sixfold — viz. 
from  O'Ol  to  0*058  per  cent. ;  the  loss  on  ignition  of  the  soil  was  much  greater 
(leaving  water  out  of  the  question) ;  the  amount  of  ammonia  had  increased 
from  an  inappreciable  quantity  to  0-016  per  cent. ;  and  the  amount  of 
nitrates  had  also  increased. 

These  results  the  committee  considered  highly  satisfactory  (especially 
when  the  extreme  porosity  of  the  soil  and  limited  area  of  land  available  for 
irrigation  are  taken  into  account),  as  in  the  experiments  of  Messrs.  Lawes 
and  Gilbert  only  from  40  to  60  per  cent,  of  the  nitrogen  applied  in  solid 
manures  was  recovered  in  the  crops  within  the  season  of  application.  The 
committee  also  called  attention  to  the  very  careful  way  in  which  the  samples 
were  taken  and  submitted  to  analysis,  the  results  obtained  for  the  sewage 
and  effluent  water  being  as  absolute  and  exact  as  accurate  gauging  and 
careful  analysis  could  make  them,  and  those  for  the  crops  calculated 
by  means  of  the  most  reliable  published  data.  The  observations  also 
cover  a  larger  area  of  land  and  a  greater  variety  of  crops  than  have  ever 
hitherto  been  scientifically  made.  As  regards  the  samples  of  sewaged  soil, 
they  were  very  carefully  taken  at  the  same  part  of  the  farm  as  the  samples 
had  been  taken  before  the  application  of  sewage,  and  were  mixed  to  form  an 
average  sample  for  submission  to  analysis. 

VOL.    I.  3  Ii 


€82  HYGIENE 

It  was  at  one  time  thought  that  sewage  when  exposed  to  the  air  in  open 
carriers  on  sewage  farms  would  lose  a  large  proportion  of  ammonia,  its  most 
valuable  fertilising  ingredient.  The  researches  of  the  Rivers  Pollution  Com- 
missioners, however,  have  shown  that  this  is  not  the  case.  On  exposure  of 
a  solution  of  carbonate  of  ammonium,  9"25  parts  in  100,000,  in  a  layer  of  only 
2  inches  deep,  to  a  strong  draught  of  air  for  three  days,  the  solution  at  the 
end  of  this  time  still  contained  the  same  proportionate  amount  of  ammonia 
— that  is  to  say,  it  lost  ammonia  precisely  in  proportion  to  the  evaporation 
that  took  place ;  or,  in  other  words,  the  difference  between  the  volatility  of 
the  ammonia  and  that  of  the  water  in  such  solution  and  after  such  a  time 
is,  under  the  most  favourable  conditions,  inappreciable.  Seeing  that  the 
sewage  in  an  open  carrier  would  generally  be  deeper  than  2  inches,  there 
is  no  reason  to  fear  any  appreciable  loss  of  fertilising  effect  from  the  evapo- 
ration of  its  contained  ammonia  during  a  flow  through  even  a  great  length 
of  conduit. 

It  is  true  that  the  evaporation  of  water  from  the  surface  of  a  sewage  farm 
is  enormous  in  amount.  The  British  Association  Sewage  Committee  found 
that,  on  an  average  of  over  a  year's  (399  days)  observation,  only  47 "3  per  cent, 
of  the  sewage  pumped  on  to  Breton's  Farm  was  discharged  through  the  deep 
drains  as  effluent  water.  The  rainfall  at  the  farm  during  the  period  of 
observation,  being  22-f)4  inches,  introduced  on  to  the  land  the  equivalent  in 
water  of  235  days'  flow  of  sewage,  so  that  the  amount  of  evaporation  from 
the  surface  of  the  land  is  seen  to  be  enormous.  But  at  the  same  time  it 
must  be  remembered  that  some  of  this  water  is  not  evaporated  at  all,  but  is 
absorbed  by  growing  vegetation,  whilst  that  which  is  evaporated  must  be  to 
a  large  extent  given  off  by  the  leaves  of  plants,  which  give  off'  water  but  not 
ammonia  ;  so  that  there  is  no  reason  to  suppose  that  excessive  evaporation 
means  a  great  loss  of  ammonia. 

We  may  conclude,  then,  both  from  a  consideration  of  the  practical  farming 
results  attained,  and  of  the  experimental  investigations  that  have  been  made, 
that  sewage  is  in  every  sense  a  valuable  manure,  for  it  enriches  the  soil  and 
gives  up  some  of  its  fertilising  ingredients  to  the  crops  growing  on  sewaged 
land,  these  ingredients  being  to  a  notable  extent  those  which  vegetation 
exhausts  from  the  soil,  and  which  it  is  the  rdle  of  manures  to  resupply  in  a 
form  capable  of  easy  assimilation  and  absorption. 

We  come  now  to  the  consideration  of  the  character  of  the  effluent  water 
from  sewage  farms,  and  to  inquire  what  degree  of  purity  such  waters  exhibit 
mider  different  local  circumstances.  From  what  has  been  previously  stated, 
it  will  be  evident  that  the  effluent  water  exhibits  its  highest  degree  of 
purity  when  the  sewage  percolates  through  the  soil,  and  is  not  applied  too 
continuously,  nor  in  too  large  volumes  to  each  plot  of  land.  The  following 
analyses  were  made  by  the  Sewage  Committee  of  the  British  Association  on 
Breton's  Sewage  Farm,  near  Romford,  where  the  soil  is  of  a  porous  nature, 
and  the  sewage  is  very  efficiently  filtered  by  percolation  through  the  soil. 
The  analyses  represent  the  average  composition  of  the  sewage  pumped  on  to 
the  farm  from  March,  1872,  to  March,  1873,  and  of  the  effluent  water  escaping 
from  the  deep  drains.  It  is  important  to  note  that  these  analyses  were  made 
of  average  samples — that  is  to  say,  of  samples  taken  in  proportion  to  the  rate 
of  flow  of  the  sewage  at  the  time,  as  indicated  by  the  gaugings.  But  in 
comparing  the  analysis  of  the  sewage  with  that  of  the  effluent  it  must  be 
remembered  that  about  two  volumes  of  sewage  are  concentrated  by  evapo- 
ration into  one  volume  of  effluent,  in  spite  of  the  addition  of  the  rain  water 
to  the  latter,  for,  as  before  stated,  only  47*3  per  cent,  of  the  sewage  applied  to 
the  land  escapes  from  the  deep  drains  as  effluent  water.     As  regards  the 


THE  DISPOSAL   OF  BE  FUSE 


883 


effluent  water,  then,  a  very  considerable  correction  is  necessary  to  rectify 
the  result,  if  the  comparisons  of  sewage  and  effluent  water  are  to  be  made 
according  to  the  respective  volumes  of  each,  by  placing  the  evaporated  water 
to  the  account  of  the  effluent. 

Results  cji/ven  in  ]}arts  per  100,000. 


Nilrogeji 

In  Solution 

In  Suspension 

Total  in  Solution 
and  Susijension 

- 

As  Ammonia 

Organic 

As  Nitrates 
and  Nitrites 

Total 

Sewage     .    .     . 
Effluent    ,     .     . 

2-6 
0-072 

1-05 
0-147 

0 

0-947 

3-65 
1-166 

1-75 
0 

5-4 
1-166 

From  these  analyses  it  will  be  seen  that  a  large  proportion  of  the  nitrogen 
in  the  effluent  exists  in  the  form  of  the  innocuous  residues,  nitrates  and 
nitrites. 

The  Elvers  Pollution  Commissioners  have  also  recorded  analyses  of  sewage 
and  effluent  from  sewage  farms,  of  which  we  may  cite  one  example.  At  the 
Lodge  Farm,  near  Barking,  where  the  soil  is  a  pervious  gravel,  the  organic 
nitrogen  was  reduced  from  3*664  parts  in  100,000  of  the  sewage  to  0'329 
parts  in  100,000  of  the  effluent  water  ;  the  ammonia  was  reduced  from  4  to 
0"8  part  per  100,000,  whilst  nitrates  and  nitrites,  which  were  absent  from 
the  sewage,  appeared  in  the  effluent  water  to  the  extent  of  nearly  3  parts 
per  100,000. 

It  would  be  possible  to  quote  other  analyses  pointing  in  the  direction  of  a 
very  highly  purified  effluent  as  the  result  of  irrigation  under  favourable 
circumstances.  But  it  will  be  enough  here  to  sum  up  the  general  results  as 
follows  : — All  the  constituents  of  sewage  are  greatly  reduced  by  irrigation, 
with  the  exception  of  chlorine,  which  is  very  slightly  reduced,  or  even  some- 
times apparently  increased,  owing  to  the  concentration  effected  by  evaporation ; 
but  the  constituents  which  are  most  effectually  removed  from  the  sewage  are 
especially  the  putrescible  organic  matters — those,  namely,  which  it  is  essential 
to  remove  both  from  an  agricultural  and  sanitary  standpoint.  Nitrates  and 
nitrites  do  not  exist  in  the  sewage,  but  are  usually  found  in  the  effluent  water 
to  some  extent,  and  are  evidence  of  the  oxidation  processes  to  which  the 
sewage  has  been  exposed  in  the  soil. 

As  a  rule,  then,  it  may  be  taken  that  nitrates  and  nitrites  are  found  to  a 
considerable  extent  in  all  well-purified  effluents,  and  that  their  absence  indi- 
cates deficiency  of  oxidation  and  inability  on  the  part  of  the  soil  to  properly 
cleanse  the  sewage. 

As  regards  farms  on  which  surface-flow,  and  not  filtration,  chiefly  takes 
place,  the  effluent  is  not  so  well  purified.  Such  farms  are  those  in  which, 
there  being  a  somewhat  retentive  soil,  systematic  under-drainage  has  not 
been  carried  out.  But  even  here,  when  the  amount  of  land  is  sufficient,  the 
oxidation  by  surface  flow,  and  the  retention  and  absorption  of  putrescible 
matters  by  growing  plants,  are  usually  capable  of  producing  an  effluent — not 
indeed  highly  purified,  but  quite  sufficiently  pure  to  enter  the  watercourses 
of  the  locality.  If  in  such  cases  the  land  is  totally  insufficient  in  area,  it 
speedily  becomes  water-logged  to  such  an  extent  that  the  sewage  flows  over 
it  and  passes  away  almost  unpurified  into  the  streams.  But  such  instances 
cannot  be  taken  as  examples  of  properly  conducted  sewage  farms,  and  are 
condemned  alike  by  advocates  and  opponents  of  sewage  irrigation. 

3l2 


P84  HYGIENE 

"Where  the  soil  of  a  farm  is  very  clayey  and  retentive,  filtration  is  an- 
impossibility  ;  and  in  such  cases  surface  flow  must  be  entirely  relied  upon, 
and  under-drainage  is  liable  to  do  more  harm  than  good,  for  the  reason  that 
in  dry  summers  large  cracks  and  fissures  form  in  the  soil,  so  that  the  sewage- 
passes  away  directly  from  the  surface  of  the  ground  to  the  under-drains  without 
having  been  purified  at  all,  and  is  discharged  in  this  condition  into  the 
streams.  Under  certain  conditions  surface-flow  may  be  relied  upon  to  give 
a  fairly  pure  eftluent,  and  we  cannot  do  better  than  quote  the  Wimbledon 
Sewage  Farm  as  an  example. 

Here  the  sewage  of  about  25,000  people  is  first  precipitated  with  lime, 
lime  and  herring-brine,  or  lime  and  sulphate  of  alumina.  The  clarified 
eliluentfrom  the  tanks  is  applied  to  sixty-six  acres  of  land,  consisting  very  largely 
of  stiff  clay  soil.  The  sewage  is  thus  seen  to  be  applied  in  the  proportion  of 
about  380  persons  to  each  acre.  The  sewage  flows  from  one  carrier  to 
another  over  the  land  on  the  catchwater  system,  such  purification  as  it 
receives  being  entirely  due  to  surface  flow  and  not  to  filtration.  There  is  no 
under-drainage,  such  under-drains  as  formerly  existed  having  been  taken  out 
of  the  ground  and  removed.  The  land  is  extensively  planted  with  Italian 
rye-grass  and  osiers,  but  cabbages  and  mangolds  are  also  grown  on  ridges, 
and  are  well  sewaged.  The  sewage  first  passes  over  successive  plots  of  rye- 
grass and  finally  over  an  extensive  osier  bed  before  reaching  the  river 
"Wandle.  On  the  occasion  of  our  visit  the  effluent,  as  it  passed  into  the  river, 
was  clear,  colourless,  and  inodorous,  and  apparently  in  a  perfectly  fit  state 
to  be  discharged  into  the  stream.  There  is  a  storm  overflow  to  the  outfall 
sewer,  which  discharges  the  storm  waters  and  sewage  after  heavy  rainfall 
on  to  an  osier  bed,  wiaere  some  of  the  suspended  matters  are  kept  back  from 
the  sewage  before  it  reaches  the  river.  The  satisfactory  result  attained  at 
Wimbledon  is  no  doubt  largely  due,  first,  to  the  removal  of  the  suspended 
matters  of  the  sewage  by  precipitation  in  tanks,  and  secondly,  to  the  com- 
paratively large  area  of  land  available  for  irrigation,  and  to  the  care  with, 
which  the  land  is  kept  cropped ;  but  even  here  we  should  expect  that  in 
winter  the  purification  would  be  less  efficiently  performed  than  in  the  warmer 
months,  as  during  the  cold  season  plant  life  and  activity  are  in  abeyance. 
This  was  found  by  the  British  Association  Committee  to  be  the  case  on  the 
Beddington  and  Norwood  Farms  when  visited  in  winter.  The  rye-grass 
yields  an  average  of  five  cuttings  in  a  season,  and  is  bought  by  farmers  in  the 
neighbourhood,  who  cart  it  off  the  land. 

It  will  be  necessary  at  this  point  to  allude  to  the  so-called  '  sewage  fungus  "■ 
{Beggiatoa  alba)  which  is  so  frequently  found  growing  on  the  sides  of  the 
carriers  on  sewage  farms,  in  the  effluent  water  channels,  and  on  submerged 
objects  in  the  streams  into  which  the  effluent  passes.  This  fungus  was 
formerly  held  to  constitute,  when  found  on  the  banks  of  rivers,  evidence  of 
the  pollution  of  the  water  with  sewage  or  with  an  unpurified  effluent.  But, 
inasmuch  as  this  fungus  feeds  largely  on  sulphur,  which  it  extracts  from 
mineral  sulphates  as  well  as  from  decomposing  organic  matters,  it  is  found  at 
other  places  than  in  sewage-polluted  waters,  and  is  therefore  in  no  way  dia- 
gnostic of  sewage  pollution.  Even  the  most  highly  purified  sewage  effluent 
■v\dll  contain  abundance  of  mineral  sulphates,  so  that  Beggiatoa  alba  is  likely 
to  be  found  in  all  waters  into  which  such  effluents  are  discharged.  It  cannot,, 
then,  he  held  to  indicate  the  presence  of  putrefiable  organic  matters  in  the 
water  of  streams  in  which  it  is  found,  but  merely  of  an  abnormal  amount  of 
sulphates.  There  seems  no  reason  either  to  believe  that  it  has  itself  any 
injurious  effect  on  the  water,  except  when  found  in  large  quantities,  when 


THE  DISPOSAL   OF  REFUSE  885 

the  fungus  may  cause  nuisance  by  rotting  in  the  water  and  giving  off  offen- 
sive gases. 

The  influence  of  sewage  farming  upon  the  public  health,  either  as  being 
productive  of  nuisance  or  actually  causative  of  disease,  must  next  arrest  our 
attention.  It  will  be  convenient  to  consider  the  question  of  nuisance  in  the 
first  place. 

There  cannot  be  the  slightest  doubt  that  badly  managed  sewage  farms 
may  give  rise  to  a  very  serious  nuisance  in  their  immediate  neighbourhood. 
The  nuisance  may  be  due  to  one  of  several  causes  : — (1)  The  sewage  may  arrive 
at  the  farm  in  a  putrid  condition  owing  to  the  length  of  time  it  has  been 
retained  in  old  and  dilapidated  or  badly  constructed  sewers.  The  application 
of  such  foul  liquid  to  a  large  surface  of  land  is  pretty  certain  to  give  rise  to 
offensive  effluvia,  which  will  be  the  cause  of  complaint.  (2)  If  ditches  dug 
in  the  soil  are  used  as  the  permanent  carriers,  much  of  the  solid  matters  in 
the  sewage  will  be  deposited  on  their  sides,  and  if  this  sediment  is  not  re- 
moved or  dug  into  the  ground,  it  will  putrefy  and  give  off"  offensive  gases. 
-(3)  Where  too  much  sewage  is  applied  to  land  consisting  of  clayey  soil,  the 
sewage  ponds  on  the  surface  and  the  stagnation  lead  to  putridity  with  its 
offensive  accompaniments. 

In  all  these  cases  it  is  obvious  that  proper  dispositions  have  not  been 
made  or  that  the  management  is  at  fault.  The  remedies  indicated  are  (1) 
the  flushing  or  reconstruction  of  defective  sewers,  so  that  the  sewage  may 
arrive  at  the  farm  in  a  fresh  and  undecomposed  condition  ;  (2)  the  adoption 
of  permanent  carriers  of  stoneware  or  concrete,  which  can  be  easily  flushed 
and  cleansed ;  (3)  the  acquisition  of  a  larger  area  of  land,  and  the  breaking 
up  and  close  under-drainage  of  that  which  is  too  impervious  to  admit  of  a 
proper  amount  of  filtration  of  the  sewage. 

As  regards  carefully  conducted  sewage  farms,  there  is  very  little  evidence 
that  nuisance  is  caused  to  the  neighbourhood.  In  dealing  with  so  foul  a 
hquid  as  town  sewage  it  is  impossible  to  avoid  all  odour  at  aU  times  and  at 
all  places  ;  but  considering  the  number  of  sewage  farms  that  now  exist,  dotted 
all  over  the  country,  the  fact  that  complaints  from  residents  in  their 
neighbourhood  are  so  infrequent  as  they  are,  is  very  valuable  testimony 
that  sewage  irrigation  is  productive  of  very  little  nuisance.  To  take  only  the 
case  of  the  Croydon  Sewage  Farm  at  Beddington,  we  learnt  from  the  late  Dr. 
Alfred  Carpenter  that  the  locality  around  part  of  the  farm  has  become  a 
residential  neighbourhood,  and  that  the  value  of  land  and  the  price  of  property 
on  the  immediate  borders  of  the  farm  have  risen  enormously  in  recent  years. 
There  are  no  complaints  of  offensive  smells  at  Norwood ;  a  public  foot-path 
through  the  irrigated  fields  is  used  as  a  pleasure  walk  by  numbers  of  people, 
many  of  whom  are  unaware  of  the  character  of  the  farm  over  which  they  are 
passing. 

There  is,  too,  but  very  little  evidence  of  disease  being  caused  even  by  badly 
conducted  sewage  irrigation.  An  outbreak  of  dysentery  and  diarrhoea  in  1864-5 
amongst  the  patients  of  the  Cumberland  and  Westmoreland  Asylum  was 
recorded  by  the  medical  officer  (Dr.  Clouston)  as  being  due  to  the  se"rt^age 
farm  which  was  in  close  proximity  to  the  asylum.  But  here  it  seems  that 
strong  and  putrid  sewage  became  ponded  on  the  irrigation  plot,  forming  a 
filthy  morass.  Sewage  is  still  applied  on  the  grounds  of  this  asylum,  with 
the  difference  that  the  irrigation  is  conducted  on  proper  principles  ;  and  from 
1874  to  1887  Dr.  Campbell,  the  present  medical  officer,  has  found  no  disease 
or  nuisance  in  any  way  arising  from  the  distribution  of  the  sewage. 

There  is,  besides,  evidence  to  show  that  the  men  who  work  on  sewage 


886  HYGIENE 

farms,  and  their  families  who  reside  there,  exhibit  a  very  low  rate  ofmortahty,. 
and  are  quite  as  healthy  as  the  labom-ers  on  ordinary  farms.  From  the 
returns  of  nine  sewage  farms  which  were  in  competition  for  the  Eoyal 
Agricultural  Society's  prizes  it  appears  that  the  death-rate  amongst  the 
residents  on  the  farms,  on  an  average  of  the  number  of  years  which  they 
have  been  in  operation,  does  not  exceed  3  per  1,000  per  annum.  This 
rate  is  very  likely  not  lower  than  that  which  would  obtain  amongst  ordinary 
agricultural  labourers,  but  still  it  shows  that  sewage  farming  is  not  detri- 
mental to  health  or  life. 

Epizootic  and  entozoic  diseases  amongst  cattle  have  not  been  shown  to 
have  been  originated  or  favoured  in  their  spread  by  sewage  irrigation.  The 
late  Dr.  Cobbold,  as  long  ago  as  1865,  published  some  considerations  which 
induced  him  to  believe  that  sewage  farming  would  tend  to  spread  entozoic 
disease  both  amongst  men  and  cattle.  With  the  view  of  testing  the  soundness 
of  the  indictment  thus  preferred  by  Dr.  Cobbold,  the  British  Association 
Sewage  Committee  subsequently  made  a  very  careful  investigation  of  the 
subject  in  conjunction  with  Dr.  Cobbold  himself,  but  they  failed  to  trace 
any  such  coimection.  The  committee  found  that  on  one  farm  there  was 
a  remarkable  absence  of  those  molluscan  and  insect  forms  of  life  which 
fi'equently  play  the  part  of  intermediary  bearers  to  entozoal  larvae,  and 
without  which  the  cycle  of  their  existence  cannot  be  continued ;  and  they 
also  pointed  out  that  alkaline  sewage  probably  destroys  organisms  whose 
natural  habitat  is  the  acid  secretion  of  the  human  intestines,  and,  if  so, 
they  must  be  destroyed  in  the  sewage  before  they  arrive  at  the  farm.  It  hag 
also  been  recorded  that  wire-worms  {Oscinis  vastator),  which  do  so  much 
injury  to  cereal  crops,  have  been  entirely  destroyed  by  dressings  of  sewage 
applied  to  the  affected  plants. 

It  may  be  stated,  then,  that  the  consumption  of  sewage-grown  produce, 
whether  by  men  or  beasts,  has  never  been  shown  to  be  a  cause  of  parasitic 
disease  in  either,  and  that  there  is  no  probability  of  its  being  ever  likely  to 
prove  so.  As  regards  the  feeding  of  cattle  on  irrigated  meadows,  it  certainly 
seems  more  cleanly  to  allow  the  sewage  to  sink  away  into  the  soil  before 
admitting  them  on  to  the  land,  though  there  seems  to  be  no  appreciable  risk 
incurred  by  a  contrary  practice. 

Subsoil  Ieeigation 

For  the  disposal  of  the  sewage  of  towns  surface  is  preferable  to  subsoil 
irrigation.  The  utilisation  is  more  complete,  the  purification  is  more  certainly 
ensured,  and  surface  carriers  are  more  easily  cleansed  than  underground 
drains.  But  for  isolated  houses  and  groups  of  houses  in  country  districts, 
where  the  purification  of  the  sewage  would  have  to  be  effected  on  land 
adjoining  inhabited  premises,  it  is  often  advisable  to  have  recourse  to  subsoil 
irrigation  in  preference  to  the  other  method.  Subsoil  irrigation  can  also  be 
relied  upon  to  purify  the  slop  waters  of  houses  in  country  districts  where 
some  form  of  dry  closet  is  in  use  for  the  disposal  of  the  solid  human 
excreta. 

The  slop  waters  of  villages  are  but  little  less  impure  than  water-closet 
sewage,  and  are  usually  got  rid  of  in  rural  districts  by  being  allowed  to  pass 
into  ditches  or  streams  ;  they  are  undoubtedly  productive  of  considerable 
nuisance.  They  contain,  however,  somewhat  less  of  solid  floating  and 
suspended  matters  than  water-closet  sewage,  so  that,  whereas  it  is  advisable 
to  strain  the  latter  liquid  to  remove  the  larger  sohd  bodies  before  using  it 
for  sub-irrigation,  such  a  proceeding  is  not  required  for  the  cleaner  slop  waters. 


THE  DISPOSAL  OF  REFUSE 


887 


A  very  small  piece  of  ground  only  is  required  to  purify  the  slop  waters  of 
a  single  cottage  or  small  house  ;  but  in  the  case  of  a  village,  where  the 
houses  are  in  fairly  close  proximity,  it  would  probably  be  better  to  adopt  a 
combined  system  and  to  carry  the  slop  waters  of  the  whole  village  in  a  pipe 
sewer  to  a  piece  of  land  outside.  Larger  houses  standing  in  good-sized 
grounds  could  purify  their  slop  waters  or  sewage  on  their  own  premises, 
and  would  probably  find  it  advantageous  to  do  so,  as  the  liquid  manure 
when  applied  to  the  land  would  no  doubt  considerably  increase  the  garden 
produce. 

The  plot  of  land  chosen  for  sub -irrigation  should  be  of  a  light  and  porous 
character,  to  ensure  the  efficient  filtration  of  the  sewage  liquid,  and  should, 
if  possible,  have  a  gentle  steady  slope.  To  avoid  the  necessity  of  pumping, 
the  plot  of  ground  should  be,  if  possible,  at  a  lower  level  than  the  house  or 
houses  from  which  the  sewage  flows.  At  a  depth  of  from  G  to  12  inches 
from  the  surface  of  the  soil  should  be  laid  a  systen  of  2-inch  porous  earthen- 
ware pipes,  placed  about  5  or  6  feet  apart,  with  open  joints  between  the 
lengths  of  pipe  (each  pipe  being  about  a  foot  in  length).  The  ends  of  the 
pipes  should  be  supported  upon  cradles,  made  of  half  pipes,  and  protected 
above  by  similar  covers,  to  allow  for  the  escape  of  the  water  and  to  pre- 
vent earth  getting  into  the  pipes  (figs. 
183  and  184).  The  system  should 
be  connected  at  its  highest  end  with 
the  water-tight  drain  conveying  the 
sewage  to  the  land,  and  from  this 
point  the  pipes  should  have  a  slight 
fall  away  of  6  or  8  inches  in 
100  feet,  and  should  ramify  under 
the  soil  over  the  entire  area  of  the 
plot. 

Where  the  soil  is  very  porous  no 
further  drainage  is  required ;  but  with 
the  more  retentive  soils  it  is  advisable 
to  lay  a  drain  at  a  short  distance  from 
the  ends  of  the  pipes  lo  collect  the 
effluent  water  and  convey  it  into  the 
watercourse. 


Fig.  ISiJ. — Drains  for  sub-irrigation. 


Fig.  184. — Sub-irrigation  drains. 

It  is  now  usual  in  the  case  of  single  houses  to  collect  the  slop  waters  or 
strained  sewage  in  a  siphon  fl.Tish  tank  (fig.  185),  which  discharges  its  contents 
automatically  at  regular  intervals  into  the  sub-irrigation  drains.  The  reason 
for  doing  so  is  that  the  waste  waters  passing  away  from  a  single  house  flow 
in  a  mere  dribble,  so  that  the  liquid  penetrates  but  a  very  short  way  along 
the  sub -irrigation  drains,  and  the  pipes  become  in  time  choked  with  de- 
posited sediment.  That  portion  of  the  sub -irrigation  plot,  also,  which  is 
nearest  the  house-drain  receives  very  much  more  than  its  proper  share 
of  the  irrigating  liquid,  so  that  its  cleansing  properties  become  speedily 
overtaxed. 

The  flush  tank  (fig.  185),  on  the  other  hand,  stores  the  dirty  water 
until  a  considerable  volume  is  collected  and  the  tank  is  full,  when  it  suddenly 


888 


HYGIENE 


discharges  its  contents,  which  escaping  in  large  vohime  with  a  high  velocity 
reach  every  part  of  the  sub -irrigation  plot.  By  this  means,  then,  each 
portion  of  the  land  receives  its  due  share  of  the  irrigating  liquid,  and 
receives  it  intermittently — viz.  at  such  periods  only  as  the  tank  discharges, 
which,  of  course,  depend  on  the  capacity  of  the  tank  in  relation  to  the  volume 
of  water  it  receives  in  the  twenty-four  hours— and  purification  and  utilisation 
are  thereby  greatly  facilitated.  The  tank  now  in  most  general  use  is  that 
fitted  with  Rogers  Field's  annular  siphon  arrangement.  This  tank  in 
practice  is  found  to  work  very  well :  a  very  small  dribble  of  water  only  is 
required  to  start  siphonage  when  the  tank  is  full ;  and  '  dribbling  '  and  '  con- 
tinuous action  ' — by  which  is  meant  that  when  the  tank  is  full,  water  dribbles 
continuously  down  the  discharge  pipe  as  fresh  water  enters  the  tank,  but 
the  tank  does  not  properly  siphon  itself— are  not  found  to  occur  if  the  tank 
is  placed  on  a  perfectly  level  surface  with  the  discharge  pipe  quite  plumb. 

The  sewage  or  slop  waters  should  be  conveyed  to  the  sub-irrigation  plot 
by  a  greater  or  less  length  of  water-tight  drain,  according  to  circumstances. 


Fig.  185. — Field's  automatic  siphon  flush  tank. 


When  the  liquid  reaches  the  porous  drains  it  very  rapidly  escapes  through  the 
open  joints  between  the  lengths  of  pipe  into  the  soil,  where  some  of  its  pol- 
luting ingredients  are  absorbed  or  assimilated  by  the  roots  of  the  grasses 
and  other  vegetables  grown  on  the  plot,  and  the  remainder  are  purified  by 
oxidation  and  nitrification  as  the  water  percolates  more  deeply  into  the  soil. 
The  purifying  agencies  are  the  same  as  in  intermittent  downward  filtration, 
of  which,  indeed,  subsoil  irrigation  is  merely  a  variety,  the  irrigating  liquid 
being  applied  a  few  inches  beneath  the  soil  instead  of  from  the  surface. 
In  like  manner,  also,  the  effluent  water  escapes  from  the  drains,  free  from 
all  polluting  organic  constituents  (provided  the  area  of  the  sub-irrigation  plot 
is  sufficiently  large  to  absorb  and  cleanse  the  sewage  applied  to  it),  and  may 
at  once  be  allowed  to  pass  into  the  nearest  watercourse.  If  the  soil  is  very 
porous,  the  efiluent  water  may  be  entirely  lost  in  it  by  percolating  deeply 
until  it  reaches  the  subsoil  water. 

The  sub-irrigation  drains  may  require  to  be  taken  out  of  the  soil,  and  any 
deposit  that  has  collected  m  them  removed  before  they  are  relaid,  about  once 
in  five  years  or  more,  according  to  circumstances. 


THE  DISPOSAL   OF  REFUSE  889 


THE   DISPOSAL   OP   MANUFACTUBING  REFUSE 

In  manufacturing  districts  the  pollution  of  streams  is  probably  quite  as 
largely  due  to  the  discharge  of  waste  waters  from  factories  as  to  the  entrance 
of  house  sewage  into  the  river  waters.  These  waste  liquors  are  in  many 
cases  of  a  highly  polluting  character,  containing  organic  refuse  of  various 
descriptions,  or  poisonous  metallic  compounds,  which  kill  the  fish  in  the 
river  and  effectually  put  a  stop  to  the  natural  processes  of  oxidation  which 
are  capable  of  repurifying  polluted  waters  under  certain  conditions  (see  p.  851). 
The  spent  liquors  from  dyeing  works  may  give  the  water  a  black  or  dark- 
coloured  appearance,  so  that  rivers  polluted  with  manufacturing  refuse  are 
often  as  objectionable  to  sight  as  they  are  to  smell  and  taste.  Of  the  offensive 
condition  of  many  streams  in  the  North  of  England  much  evidence  will  be 
found  in  the  reports  of  the  Rivers  Pollution  Commission. 

There  can  be  no  doubt  that  town  sewage  is  far  easier  to  deal  with,  having 
regard  to  its  purification  and  utilisation,  when  unmixed  with  manufacturing 
refuse,  which  often  contains  strong  acids  or  alkalies  or  other  poisonous  resi- 
dues, and  are  exceedingly  injurious  to  vegetation  when  the  sewage  is  ap- 
plied to  land.  On  the  other  hand,  it  is  impossible  for  municipal  authorities 
to  exclude  such  waste  matters  from  the  sewers,  and  it  is  difficult  to  see  how 
the  manufacturers  themselves  could  efficiently  purify  their  waste  liquids  on 
their  own  premises,  which  are  often  of  very  limited  extent,  when  situated 
within  the  town  boundaries. 

The  Elvers  Pollution  Commissioners  expressed  the  opinion  that  '  for 
populous  places  which  are  also  seats  of  manufacture  it  would  generally  be 
possible,  without  materially  complicating  the  sewage  problem,  to  allow  the 
fluid  refuse  of  industrial  processes  with  few  exceptions  to  pass  into  the 
sewers  to  be  disposed  of  as  common  sewage,  the  special  exceptions  being 
the  refuse  of  workers  in  metals  and  of  manufacturers  of  gas,  paraffin  oil, 
pyroligneous  acid,  and  animal  charcoal ;  that,  subject  to  some  such  exceptions 
as  these  and  to  proper  regulations,  the  discharge  of  fluid  industrial  refuse 
into  sewers  would  generally  not  render  the  sewage  more  difficult  of  use, 
and  would  in  some  cases,  in  respect  of  certain  contained  refuse  matters, 
greatly  increase  the  agricultural  value  of  the  sewage.'  For  instance,  the 
waste  liquor  from  flannel  works  is  exceedingly  rich  in  ammonia  and  organic 
matters,  that  from  works  at  Newtown  being  found  to  contain  in  100,000 
parts  no  less  than  1733'4  of  suspended  organic  matters,  446-353  of  dissolved 
organic  carbon,  91 'IBS  of  dissolved  organic  nitrogen,  and  80*012  of  ammonia. 
But  such  cases  of  enrichment  of  sewage  are  probably  exceptional,  and  can- 
not be  held  to  contradict  the  truth  of  the  statement  that  sewage  is  easier  to 
treat  when  unmixed  with  industrial  refuse. 

Probably  the  best  means  of  dealing  with  the  sewage  of  manufacturing 
towns  is  that  pursued  at  Birmingham,  of  which  mention  is  made  at  page  864, 
The  preliminary  precipitation  with  lime  carries  down  many  of  the  compounds 
which  would  prove  deleterious  to  vegetation,  and  neutralises  the  acidity 
arising  from  the  presence  of  free  acids  or  acid  salts  in  the  sewage.  The 
clarified  and  alkalinised  effluent  from  the  tanks  can  then  be  applied  to  land 
with  every  prospect  of  attaining  a  successful  result,  both  as  regards  its  puri- 
fication and  its  utilisation  in  the  production  of  crops. 

For  factories  situated  away  from  towns,  where  no  outlet  for  waste  waters 
into  town  sewers  is  possible,  it  would,  as  a  rule,  be  desirable  to  resort  to 
intermittent  downward  filtration  upon  a  specially  prepared  and  under-drained 
plot  of  land  in  the  vicinity  of  the  works.     In  most  cases  it  would  probably 


890  HYGIENE 

be  useless  to  attempt  to  raise  crops  on  the  filtration  area,  as  the  waste 
liquors,  even  if  they  contain  valuable  manurial  ingredients  and  are  free  from 
poisonous  salts  or  residues,  usually  contain  these  matters  in  too  high  a  pro- 
portion, \\'ith  the  result  that  only  weeds  and  coarse  grasses  flourish  on  the 
irrigated  land,  the  finer  produce  being  injured  or  killed.  A  preliminary  pre- 
cipitation of  the  waste  waters  with  lime  would  no  doubt  tend  to  a  more 
successful  result  in  the  way  of  rearing  produce,  but  the  cost  would  pro- 
bably be  prohibitive,  and  the  ultimate  cleansing  of  the  dirty  water  would 
be  but  httle  enhanced.  It  would,  however,  appear  to  be  desirable  in  the 
case  of  acid  wastes  to  neutralise  the  liquid  with  hme  Tsathout  attempting  to 
precipitate  it,  otherwise  nitrification  of  ammonia  and  organic  matters  in  the 
surface  layers  of  the  soil  may  be  very  greatly  diminished,  owing  either  to  the 
destruction  of  the  nitrifying  organisms  themselves,  or  to  the  absence  of  the 
salifiable  base  which  should  be  present  in  the  soil  for  the  nitrous  and  nitric 
acids,  when  formed,  to  combine  with. 

It  has  been  amply  demonstrated  that  intermittent  downward  filtration 
carefully  carried  out  on  a  suitable  soil  is  capable  of  purifying  the  very  foulest 
specimens  of  industrial  waste  waters,  and  this  is  then  the  method  which 
should  be  everywhere  employed  where  land  of  suitable  quality  and  extent 
can  be  obtained.  If  it  is  found  impossible  to  acquire  the  necessary  land, 
then  an  attempt  should  be  made  to  precipitate  the  suspended  matters  in 
tanks  by  means  of  lime  or  other  chemical  substance,  and  to  further  purify 
the  efiluent  by  intermittent  filtration  through  banks  of  coke,  cinders,  or  ashes. 
In  this  way  it  will  be  possible  to  procure  a  colourless  and  clear  effluent, 
which,  if  not  entirely  free  from  soluble  polluting  ingredients,  is  at  least  in- 
capable of  doing  much  injury  to  the  water  of  the  stream  into  which  it  is 
discharged. 


THE  INFLUENCE  OF  SANITAEY  WOEKS  UPON  PUBLIC  HEALTH 

It  is  perhaps  hardly  necessary  at  the  present  time  to  recapitulate  the 
evidence  as  to  the  beneficial  effect  upon  the  pubhc  health  of  the  works  of 
sewerage,  drainage,  and  water  supply,  which  have  been  so  marked  a  charac- 
teristic of  the  social  progress  of  the  latter  half  of  the  present  century.  It  is 
pretty  generally  recognised  now  that  filth  and  disease  stand  to  each  other  as 
cause  and  effect ;  but  inasmuch  as  there  is  a  tendency  to  forget  facts  which 
are  not  presented  to  us  constantly  in  every-day  life,  a  brief  resume  of  the 
subject  may  not  here  be  out  of  place. 

Although  accurate  statistics  are  not  available  until  civil  registration  began 
at  the  commencement  of  the  present  reign,  we  can  picture  to  ourselves  fairly 
correctly  the  condition  of  the  public  health  in  the  seventeenth  and  eighteenth 
centuries.  In  1593  was  commenced  the  system  of  registration  of  births  and 
deaths  by  the  parish  clerks  of  London  from  which  we  get  a  knowledge  of 
the  causes  of  death,  although  it  is  impossible  to  construct  death-rates,  there 
being  no  enumeration  of  population.  That  the  death-rate  during  two 
centuries — 1600  to  1800— must  have  been  excessive,  we  know  from  the  large 
proportion  to  the  total  mortality  of  deaths  from  zymotic  diseases,  ague,  and 
consumption,  which  invariably  indicate  a  high  general  death-rate.  So  high, 
indeed,  was  the  death-rate  that  the  annual  deaths  invariably  exceeded  the 
births  in  London,  and  the  population  was  only  prevented  from  diminishing 
by  immigration  from  the  rural  districts.  Ague,  dysentery,  and  consumption 
figured  largely  in  the  mortality  bills,  and  the  mortality  amongst  infants  and 
young  children  was  enormous.     Typhus,  small-pox,  and  measles  caused  a 


THE  DISPOSAL   OF  REFUSE  891 

large  number  of  deaths,  and  in  the  sixteenth  century  plague  and  sweating 
sickness  were  epidemics  causing  an  enormous  mortality,  and  even  decimating 
the  population  in  certain  years.  Even  in  years  when  plague  was  absent, 
preventable  fevers  alone  probably  accounted  for  at  least  one- quarter  of  the 
deaths. 

The  causes  of  the  excessive  mortality  must  be  sought  in  the  filthy  con- 
dition of  the  city  itself.  The  streets  were  unpaved,  or  paved  only  with  rough 
cobble  stones.  There  were  no  sidewalks.  The  houses  projected  over  the 
roadway,  and  were  unprovided  with  rain-water  gutters,  so  that  during  a 
shower  the  rain  fell  from  the  roofs  into  the  middle  of  the  street.  The  streets 
were  filthy  from  constant  contributions  of  slops  and  ordure  from  animals  and 
human  beings,  any  system  of  scavenging  being  unknown.  There  were  no 
underground  drains,  and  the  soil  of  the  town  was  soaked  with  the  filth  of 
centuries.  This  sodden  condition  of  the  soil  must  have  affected  the  wells  to 
a  considerable  extent.  The  streets  were  filthy  without,  the  houses  were 
filthy  within.  The  rooms  of  the  poor  were  more  like  pigstyes  than  human 
habitations,  unventilated  and  strewn  with  rushes,  which  were  seldom  changed,. 
and  the  wretched  inhabitants  closely  packed  in  these  miserable  hovels  must 
have  been  very  prone  to  sufi'er  from  infection  of  all  kinds.  The  city,  too,  was 
surrounded  with  marshes,  and  this  fact  accounts  for  the  exceeding  prevalence 
of  ague  and  dysentery.  ^ 

Coming  now  to  the  present  century,  the  sanitary  condition  of  houses 
and  towns  forty  or  fifty  years  ago  all  over  the  country  was  far  superior  to 
that  described  as  being  characteristic  of  ancient  London.  But  the  system 
which  was  then  almost  everywhere  prevalent  of  collecting  large  accumula- 
tions of  human  refuse  in  cesspools  and  midden  pits,  the  consequent  pollution 
of  well  waters,  and  the  absence  of  any  proper  scavenging  arrangements, 
caused  still  a  high  mortality  amongst  the  population  generally,  and  a  very 
considerable  endemic  prevalence  of  enteric  fever,  not  to  mention  occasional 
outbreaks  of  cholera  and  other  diseases,  invariably  dependent  upon  faulty 
methods  of  refuse  disposal.  The  reports  of  the  Health  of  Towns  Commission, 
1844-5,  and  of  the  Sewage  of  Towns  Commission,  1861,  drew  forcible  attention 
to  these  faulty  conditions  as  being  the  causes  of  much  preventable  sickness  and 
mortality,  and  their  publication  stimulated  local  sanitary  authorities  to  under- 
take those  works  of  sewerage,  drainage,  and  water  supply  which  were  so 
urgently  needed  in  the  interests  of  improved  pubhc  health. 

The  great  improvement  in  health,  as  evidenced  by  lowered  death-rates, 
which  followed  the  execution  of  these  sanitary  works,  is  very  fully  brought  to 
hght  in  a  report  by  Dr.  Buchanan  '  on  the  results  which  have  hitherto  been 
gained  in  various  parts  of  England  by  works  and  regulations  designed  to 
promote  the  Public  Health'  (Ninth  Eeport  of  the  Medical  Officer  of  the 
Privy  Council,  1866).  Twenty-five  towns,  of  very  different  populations,  were 
chosen  to  illustrate  the  effects  of  improved  sanitation,  these  being  the  towns 
where  at  that  time  structural  sanitary  works  had  been  most  thoroughly  done, 
and  had  been  longest  in  operation.  The  nature  of  the  sanitary  operations 
carried  out  in  these  towns  was  as  follows  : — A.  Drainage  works  affecting 
surface,  subsoil,  or  houses.  B.  Improvements  in  water  supply — amending 
previous  sources  or  substituting  or  adding  new  ones.  C.  Measures  designed 
for  the  removal  of  decomposing  organic  matters  or  for  preventing  contami- 
nation of  air  or  water  thereby,  viz.  1.  The  substitution  of  water-closets  for 
cesspools  and  middens.  2.  The  improvement  of  middens.  D.  Improved 
paving,  scavenging,  and  public  cleanliness.     E.  Amendments  of  the  lodg- 

^  London,  Ancient  and  Modern,  from  a  Sanitary  Point  of  View.    By  Dr.  G.  V.  Poore. 


892 


HYGIENE 


ment  of  the  inhabitants,  the  regulation  of  common  lodging-houses,  and  the 
repression  of  overcrowding. 

Of  these  towns,  twenty  exhibited  a  reduction  in  the  death-rate  for  the 
period  after  the  completion  of  the  sanitary  works  as  compared  with  a  certain 
period  before  the  works  were  commenced.  The  reduction  was  greatest  in  the 
cases  of  towns  like  Cardifl"  and  Newport  (32  per  cent,  reduction,  or  omitting 
cholera  23  per  cent.),  where  the  previous  death-rate  was  very  high  from  the 
existence  of  notable  sanitary  defects  ;  and  was  least  in  towns  like  Bristol, 
where  the  pre^dous  death-rate  was  not  excessive. 

The  reduction  of  the  death-rate  from  enteric  (typhoid)  fever  is  especially 
noteworthy.  In  nine  towns  the  reduction  exceeded  50  per  cent.,  being 
highest  in  Salisbury,  where  the  former  rate  of  0*75  per  1,000  was  reduced  to 
0'175  per  1,000 — a  reduction  of  over  75  per  cent.  In  ten  towns  the  reduc- 
tion varied  between  33  and  50  per  cent.  ;  in  two  there  was  a  trivial  reduction, 
and  in  three  (Chelmsford,  Penzance,  and  Worthing)  more  or  less  increase. 
The  reason  of  the  increase  in  these  three  towns  is  explained  by  the  fact  of 
insufficient  ventilation  of  the  sewers,  combined  with  backing  up  of  sewage  in 
them,  so  that  sewer  gases  found  their  way  into  the  houses. 

It  is  instructive  to  follow  up  the  decreased  rates  in  these  towns  by  a  refer- 
ence to  the  rates  exhibited  in  modern  years,  the  interval  between  186G  and  the 
present  time  being  no  doubt  occupied  in  perfecting  the  sanitary  works  which 
had  at  the  former  period  only  recently  been  completed.  We  can  take  the 
cases  of  Cardiff,  Leicester,  and  Bristol,  which  are  three  of  the  large  towns  the 
statistics  of  which  are  published  in  the  reports  of  the  Registrar-General. 


- 

General  Death-rate  per  1,000 

1 
Enteric  Fever  Death-rate  per  1,000 

1847-54 

1859-C6 

188-1-8 

1847-54 

1859-66 

188-1-8 

Cardiff  .     .    , 

33-2 

22-6 

23 

1-75 

1-05 

0-40 

1845-51 

1862-4 

1884-8 

1845-51 

1862-4 

1S84-8 

Leicester    . 

26-4 

25-2 

20 

1-45 

0-77 

0-22 

1845-7 

1861-2 

1884-8 

1845-7 

1861-2 

1884-8 

Bristol  .     .     - 

24-5 

24-2 

18-9 

1-0 

0-65 

0-14 

It  wiU  be  seen  that,  except  in  the  case  of  Cardiff,  where  an  altered  social 
condition  of  the  population  may  account  for  the  discrepancy,  the  general 
death-rates  of  the  towns  have  been  much  lowered  in  recent  years.  The 
lowering  of  the  enteric  fever  death-rate  is  even  more  remarkable,  and  should 
be  still  more  apparent  than  is  shown  by  the  tables  ;  for  the  rates  for  the 
period  1884-8  are  for  '  fever,'  which  includes  typhus  and  simple  continued 
fever  as  well  as  enteric.  Typhus  and  simple  continued  fever  formed  17 
per  cent,  of  the  mortality  from  '  fever '  in  England  and  Wales  during  the 
period  in  question  (1884-8),  so  that  17  percent,  of  the  rates  given  under  this 
head  for  the  three  towns  in  the  table  should  be  deducted  to  render  the  com- 
parison complete. 

That  these  three  towns  are  not  exceptional  instances  is  shown  by  the  fact 
that  the  whole  country  exhibits  a  similar  decrease  in  enteric  fever  mortality 
during  the  corresponding  period  (see  diagram,  p.  893).  In  1869  (the  first  year 
in  which  enteric  fever  returns,  as  separate  from  '  fever,'  are  obtainable)  the 
death-rate  from  enteric  fever  in  England  and  Wales  was  0*39  per  1,000  of 
the  population,  and  has  steadily  declined  to  the  present  time,  the  death-rate 
in  1887  and  1888  being  only  0-182  per  1,000  and  0-169  per  1,000,^  a  reduc- 
'  In  1889  the  enteric  fever  death-rate  was  0-173  per  1,000  ;  in  1890  it  was  0-179  per  1,000. 


THE  DISPOSAL   OF  BEFTJSE 


893 


tion  of  over  50  per  cent,  in  less  than  twenty  years.  The  curve  in  the  diagram 
is  interesting  as  showing  the  rapid  decrease  in  1876  and  1877,  which  follow- 
ing as  it  did  upon  the  passing  of  the  Public  Health  Act  of  1875,  and  the 
appointment  of  medical  officers  of  health  throughout  the  country,  is  ifficient 
evidence  of  the  beneficial  results  that  can  be  obtained  by  sanitary  xmprove- 
ments — more  especially  of  those  which  have  for  their  object  the  removal 
of  excreta  by  water  carriage  and  the  introduction  of  a  pure  water  supply. 

The  same  fact  is  brought  to  light  in  a  rather  different  way  by  the  accom- 
panying table,  page  894,  which  is  taken  from  the  Fifty-third  Annual  Keport 
of  the  Registrar-General,  1890.   From  this  table  it  will  be  seen  that  forty  years 

DeathTXZte  I869  I870  I87l   1872  1873  IS7*  1875  1376  1877  1878  1679  1880  1^31  1862  1883  1884 1885  1888  1887  1888 

fer  1.000. 

•39 


•38 

•57 

•36 

•35 

•34 

•33 

•32 

•31 

•30 

•29 

•28 

•27 

-26 

•25 

•24 

•23 

•22 

•21 

■20 

•19 

•18 

•17 

•16 
Fig.  186, 


~\ 

V' — =v 

\ 

\ 

\ 

\ 

\ 

\ 

^    \ 

'  '\ 

V-A 

i 

\ 

.-A...     1 

1 

ut 

\ 

\ 

' 

/ 

\ 

1 

T 

\ 

r 

! 

\ — 1 

\  A 

~^ 

u 

1 

\ 

\  . 

"~— \ 

V 

N 

-Curve  showing  death-rate  from  enteric  (typhoid)  fever  in  England  and  Wales 
from  the  year  1869. 


ago  the  general  death-rate  in  urban  districts  was  considerably  in  excess  of  the 
rate  current  in  rural  districts.  Both  rates  have  declined,  but  the  urban  death- 
rate  to  a  considerably  greater  extent  than  the  rural  death-rate,  for  the  reason 
that  sanitary  works  and  measures  have  been  prosecuted  to  a  far  greater 
extent  in  towns  than  in  the  country,  and  the  town  populations  have  conse- 
quently derived  a  greater  advantage  from  sanitary  improvements  than  the 
rural  communities.  The  difference  in  death-rate  between  town  and  country, 
although  really  greater  than  here  shown,  owing  to  absence  of  correction  of 
the  rates  for  the  differing  age  and  sex  distribution  in  the  respective  populations, 
is  seen  to  be  but  slight  at  the  present  time  as  compared  with  the  differences 
in  earlier  years,  when  the  sanitary  conditions  mider  which  rural  populations 
existed  were  immeasurably  superior  to  those  of  the  town  populations. 

Illustrations  of  the  effect  of  sewerage  on  the  diminution  of  enteric  fever 


694 


HYGIENE 


- 

Death-rate  per  1,000  living  in 

Death  in  Town  Districts 

to  100   Deaths  iu  Country 

Distviots  iu  equal 

numbers  liviug 

England  and 

Town  Districts 

Country  Districts 

1851-60 

1861-70 

1871-80 

1881-90 

1881 

1882 

1883 

1884 

1885 

1886 

1887 

1888 

1889 

1890 

22-2 
22-5 
21-4 
19-1 
18-9 
19-6 
l9-(; 
19-7 
19-2 
19-5 
19.1 
18-1 
18-2 
19-5 

24-7 
24-8 
231 
20-3 
20-1 
210 
20-7 
20-9 
20-1 
20-4 
20-2 
19-0 
19-3 
20-9 

19-9 
19-7 
19-0 
17-3 
lC-9 
17-3 
17-9 
17-6 
17-8 
18-0 
17-2 
16-6 
16-4 
17-4 

124 
126 
122 
117 
119 
121 
116 
119 
113 
113 
117 
114 
118 
120 

prevalence  and  mortality  may  be  taken  from  abroad  as  well  as  from  English 
cities.  A  very  striking  example  is  furnished  by  Mmiich,'  which,  prior  to  the 
year  1880,  when  the  city  drainage  was  completed,  was  a  city  standing  on 
ground  riddled  with  porous  cesspools.  From  18G6  to  1881  the  average  yearly 
admissions  of  enteric  fever  to  hospital  were  591.  In  1880  the  admissions 
were  492,  but  fell  in  1881 — the  sewerage  works  being  then  completed — to 
99  ;  and  from  1881  to  1888  the  yearly  admissions  average  only  104,  or  little 
more  than  one-sixth  of  the  number  admitted  annually  prior  to  the  drainage 
works.  From  18G6  to  1880  the  average  number  of  deaths  from  enteric  fever 
in  a  year  was  208  ;  from  1881  to  1888  the  average  yearly  number  was  only 
40.  From  1866  to  1888  the  population  of  Munich  has  nearly  doubled, 
showing  a  rise  from  152,000  in  1866  to  278,000  in  1888,  so  that  the  enteric 
fever  rates  per  1,000  of  the  population  in  the  pre-di'ainage  period  were  3'82 
(hospital  admissions)  and  1*15  (deaths)  and  in  the  period  subsequent  to 
drainage  0'42  and  0-16  respectively.  This  great  result  is  to  be  ascribed 
almost  exclusively  to  the  sewerage  of  the  city  and  not  to  the  introduction  of 
a  new  supply  of  water  from  a  distance,  for  the  sudden  lowering  of  the  enteric 
fever  mortality  took  place  in  1881,  soon  after  the  completion  of  the  sewerage 
system,  whereas  the  improved  water  supply  was  not  carried  out  until  some 
years  later. 

A  not  less  important  result  than  the  diminishing  prevalence  and  fatality 
of  enteric  fever  is  the  practical  extinction  of  cholera  in  this  country.  There 
has  been  no  cholera  epidemic  in  this  country  since  1866.  The  absence  of 
this  terrible  scourge  can  hardly  be  attributed  to  want  of  opportunity,  for  on 
several  occasions  cholera  infection  has  reached  our  ports,  but  must  rather 
be  looked  for  in  the  improved  sanitary  conditions  under  which  the  town 
populations  now  exist,  so  that  the  contagion  even  if  introduced  fails  to 
establish  a  footing,  and  disappears  for  lack  of  those  filth-engendered  con- 
ditions under  which  alone  can  it  exert  its  powers  of  propagation.  The 
epidemic  of  1866  was  mild  in  comparison  with  that  of  1854,  and  this  in  its 
turn  caused  a  far  less  mortality  than  its  forerunner  of  1848-9.  All  the 
twenty-five  towns  examined  by  Dr.  Buchanan  showed  this  reduction,  and  in 
many  cases  the  epidemic  of  1866  passed  them  by  altogether,  although  the 
previous  outbreaks  had  been  productive  of  a  high  mortality. 

The  mortality  from  diarrhoea  was  found  to  be  greatly  reduced  in  many 
towns  where  sanitary  improvements  had  been  effected,  but  the  reduction 

'  Milnchener  neueste  Nachrichten.    By  Professor  von  Ziemssen,  1889. 


THE  DISPOSAL   OF  BEFUSE  895 

was  bj  no  means  so  universal  as  in  the  case  of  enteric  fever,  and  in  some 
cases  the  mortahty  had  increased  no  doubt  as  the  result  of  an  altered  age 
distribution  of  the  population,  a  high  birth-rate  causing  an  increased  pro- 
portion of  infants  and  young  children  in  the  population,  on  whom  principally 
diarrhoea  exerts  its  effects. 

Scarlet  fever,  measles,  and  whooping  cough  appear  to  have  been  but  little 
influenced  as  causes  of  death  by  the  improvements  in  sanitary  condition 
consequent  upon  the  execution  of  works  of  sewerage ;  whilst  of  croup  and 
diphtheria  Dr.  Buchanan  reported  that  they  had  increased  in  almost  all  the 
twenty-five  towns  during  or  after  the  completion  of  their  sanitary  works, 
and  in  many  cases  diphtheria  seemed  to  have  appeared  during  these  altera- 
tions and  to  have  increased  after  them.  Since  the  date  of  Dr.  Buchanan's 
report  (1866)  diphtheria  has  been  steadily  increasing  as  a  cause  of  death  in 
most  of  our  large  towns.  It  was  formerly  regarded  as  being  to  a  far  greater 
extent  a  rural  than  an  urban  disease  ;  but  this  view  can  no  longer  be  enter- 
tained when  it  is  stated  that  the  death-rate  in  London  from  this  disease  alone 
was  0-37  per  1,000  in  1889,  and  0-33  per  1,000  in  1890,  and  that  it  figures 
almost  if  not  quite  so  largely  now  as  a  cause  of  death  in  the  weekly  records 
as  measles  and  whooping  cough,  and  far  exceeds  scarlet  fever.  A  satisfactory 
explanation  is  still  wanting  of  this  increasing  mortality,  but  it  is  certain  that 
diphtheria  is  little  influenced  by  the  sanitary  improvements  which  have  so 
marked  an  effect  upon  enteric  fever. 

One  other  disease  remains  to  be  mentioned  as  having  been  very  greatly 
influenced  in  fatality  by  the  sanitary  improvements  enumerated  in  Dr. 
Buchanan's  report.  In  fifteen  towns  out  of  the  twenty-five  examined  the 
phthisis  death-rate  exhibited  a  reduction  varying  from  49  to  11  per  cent. 
This  reduction  can  only  be  attributed  to  the  drying  of  the  subsoil  which 
accompanied  the  laying  of  the  main  sewers  in  the  improved  towns.  Where 
the  drying  of  the  subsoil  was  greatest,  and  where  it  was  most  needed,  as  in 
Salisbury,  Ely,  Eugby,  and  Banbury,  there  the  deaths  from  consumption 
showed  the  greatest  reduction.  In  the  towns,  on  the  other  hand,  where  the 
drying  of  the  subsoil  was  inconsiderable,  or  had  not  taken  place  at  all, 
phthisis  was  found  to  be  stationary  or  had  even  increased.  In  some  cases 
this  was  due  to  the  fact  that  the  soil  already  contained  little  water,  and  so 
did  not  require  draining,  whilst  in  others  the  soil  required  draining,  but  no 
subsoil  drainage  had  accompanied  the  laying  of  impervious  pipe  sewers, 
superficial  culverts  for  storm  waters  only  being  thought  necessary. 


OFFENSIVE  AND  NOXIOUS  BUSINESSES 


BY 


THOS.  WHITESIDE  HIME,  B.A.,  M.D. 


VOL.  I.  3  n 


OFFENSIVE   BUSINESSES 

The  businesses  which  may  come  under  the  notice  of  the  Health  Officer  as 
giving  rise  to  nuisance,  or  proving  injurious  to  the  health  of  the  community, 
are  innumerable  ;  and  they  can  only  be  classified  with  difficulty.  They  may, 
perhaps,  be  best  dealt  with  under  the  heads  of  (A)  businesses  dealing  with 
animal  and  vegetable  matters ;  and  (B)  those  in  which  kno.vn  gases  or 
vapours  of  mineral  substances  are  evolved. 


A.    BUSINESSES  DEALING  WITH  ANIMAL   AND   VEGETABLE 

MAT TEES 

These  can  scarcely  be  further  classified,  and  will  be  described  seriatim. 
The  slaughtering  of  animals  for  food  is  a  business  to  which  a  separate 
article  is  devoted  (<i.v.) 

SLAUGHTERING   OF  ANIMALS 

The  following  is  the  mode  of  disposal  of  the  most  important  parts,  com- 
monly regarded  as  '  offal :  ' — 

1.  The  blood  of  pigs  and  sheep  is  either  used  for  making  '  black  puddings,' 
mixed  with  fat  and  condiments  ;  or  it  is  used  for  pig's-food  ;  or  it  is  used  for 
making  albumen  (for  which  purpose  the  blood  is  received  in  shallow  pans, 
allowed  to  coagulate,  and  the  clot  being  removed  for  manure  the  serum  is 
condensed  and  coagulated  for  albumen);  or  the  fibrin  having  been  removed 
the  remainder  is  sent  to  the  turkey  red  dyer  {vide  Turkey  Eed). 

2.  The  Viscera. — The  first  stomach  (paunch,  tripes)  of  cattle  and  sheep 
is  cut  open,  emptied  and  cleaned  for  human  food.  The  second  stomach  is 
usually  used  as  food  for  dogs  or  pigs.  The  heart  is  used  as  food  for  man  ; 
the  lungs  and  liver  are  used  so  occasionally,  but  are  more  commonly  given 
to  animals.  The  small  intestines  (running  gut)  are  either  sent  to  the  gut- 
scraper,  after  all  the  fat  has  been  cut  off  them,  or  they  are  used  for  food  for 
animals,  or  thrown  on  the  dung-heap.  The  small  intestines  of  pigs  are  used 
as  sausage-skins,  or  go  to  the  gut-scraper  ;  the  large  intestines  are  used  asf 
human  food. 

The  fat  of  pigs  is  usually  rendered  into  lard  by  the  pig-killer  himself. 
The  fat  of  cattle  and  sheep  is  commonly  removed  soon  to  the  fat-melter. 
The  hides  of  cattle  go  to  the  tanner ;  their  feet  to  the  tripe-boiler,  and 
sheep-skins  to  the  fellmonger. 

POULTEY 

The  keeping  of  poultry  in  large  towns  is  often  a  great  nuisance,  especially 
as  it  is  generally  in  the  very  poorest  localities,  where  air  and  space  are  so 
scarce,  that  people  will  insist  on  keeping  them.  Poor  people  will  keep  fowls 
in  the  cellars  of  their  houses,  or  in  the  very  small  yards  attached  to  them, 

3m  2 


900  HYGIENE 

and  endure  continuous  hostility  from  their  neighbours,  rather  than  give- 
them  up.  There  is  no  way  of  abating  tliis  nuisance,  as  a  rule,  except  by 
abolishing  it.  Poultry  are  almost  invariably  brought  dead  to  the  food  market 
or  poultry  dealer's  ;  and  it  would  be  a  great  advantage  if  it  were  customary 
to  have  them  plucked  also  before  they  are  brought  from  the  country. 

Knackekies  ;   Hobse-slaughtering 

The  knacker  (originally  knacker  =  saddler,  who  killed  the  animal  and 
utilised  the  skin)  is  a  most  useful  public  servant,  not  always  held  in  such 
estimation  as  he  deserves.  He  properly  is  a  horse-slaughterer,  but  he  also 
slaughters  old  and  diseased  animals  other  than  horses,  and  commonly  receives- 
carcases  of  animals  which  have  died  of  disease  or  violence  as  well.  The 
slaughtering  of  horses  for  food  for  man  in  such  places  should  not  be  tolerated. 
There  is  no  reason  why  such  animals  should  not  very  commonly  be  killed 
where  they  are  kept,  instead  of  being  conveyed  alive,  and  at  much  greater 
trouble,  to  the  place  of  slaughter. 

These  places  can  be  and  should  be  conducted  so  as  to  be  no  more  nuisance 
than  is  a  slaughter-house  for  cattle.  Frequently  they  are  managed  in  a  very 
offensive  manner.  In  large  towns  they  are  often  situated  in  poor,  populous 
districts,  sometimes  in  the  suburbs. 

The  principal  sources  of  nuisance  arise,  not  from  the  slaughtering,  but 
from  subsidiary  trades — bone-boihng,  flesh-boiling  (for  cat's-meat  or  fat- 
extraction),  manure-makmg,  &c. — which  are  commonly  carried  on  at 
knackeries  to  utilise  the  materials. 

Where  there  is  a  large  business  many  Uve  animals  may  be  received  daily, 
and  may  have  to  be  kept  for  some  days,  necessitating  the  provision  of  food 
and  shelter  for  them. 

The  horse  is  slaughtered  in  the  same  manner  as  an  ox  (by  the  poleaxe  or 
the  head-strap  and  spike),  and  afterwards  all  the  soft  parts  are  stripped  fi-om 
the  skeleton,  which,  in  turn,  is  broken  up  and  utilised  for  boiling  (fat,  size, 
&c.),  like  all  the  rest  of  the  carcase,  except  the  feet  and  the  long  hair  of  the 
tail. 

Knackeries  may  become  offensive  owing  to  the  filthy  way  in  which  the 
live  animals  are  kept  before  slaughter,  or  owing  to  putrid  carcases  or  other 
material  being  allowed  to  remam  on  the  premises  ;  or  owing  to  the  steam  from 
the  boiling  of  bones  and  meat,  or  in  consequence  of  the  hot  boiled  material 
being  left  lying  about  to  cool,  and  giving  off  offensive  vapour  ;  when  putiid 
stuff'  has  been  boiled  this  nuisance  is  greatly  increased.  Complaints  are  also 
sometimes  made  of  very  offensive  smells  from  the  public  drains,  owing  to 
the  liquor,  especially  if  it  is  hot,  being  discharged  into  them.  But  the  dis- 
charge of  liquids  at  over  80°  F.  temperature  is  now  prohibited  by  statute. 

The  general  principles  for  preventing  nuisance  arising  from  knackeries 
are  precisely  the  same  as  those  laid  down  for  the  construction  and  manage- 
ment of  slaughter-houses  for  cattle  (q.v.),  the  cardinal  point  being  the 
observance  of  strict  cleanliness.  The  premises  must  be  conveniently  situ- 
ated, well  lighted,  ventilated,  drained,  and  surrounded  by  a  wall  to  conceal 
from  the  view  of  the  neighbours  all  the  operations  going  on  inside.  The 
floors  should  be  impervious,  smooth,  properly  guttered,  and  sloped  towards 
the  drains.  The  bottom  5-6  feet  of  the  wall  should  be  coated  with  glazed 
tiles  or  bricks,  concrete,  or  other  impervious  material,  which  can  be  tho- 
roughly washed  with  a  hose  and  brush.  The  less  woodwork  there  is  the 
Letter  ;  and  wherever  possible  iron  should  be  substituted  for  it. 

Proper  receptacles,  with  well-fitting  lids,  should  be  provided  for  convey- 


OFFENSIVE  BUSINESSES  901 

ing  all  garbage  from,  and  as  far  as  possible  for  conveying  offensive  stuff 
to  the  works.  Much  annoyance  would  be  avoided  by  the  use  of  a  suit- 
able covered  waggon  and  the  application  of  deodorants.  Knackers  seem  to 
pride  themselves  on  the  light,  skeleton-like  character  of  their  carts,  which 
should,  on  the  contrary,  be  closed  and  substantially  made.  There  should  be 
no  dung-heap  on  the  premises ;  all  such  stuff  should  be  removed  daily  in 
proper  vessels.  If  there  are  more  carcases  brought  in  than  can  be  dealt 
with  in  the  ordinary  way,  they  should  be  buried  or  destroyed,  and  must 
not  be  left  lying  putrefying  about  the  place.  Carcases  exposed  to  the 
action  of  steam  under  pressure  in  a  receptacle  are  soon  reduced  to  a  pulp, 
the  bones  being  blanched,  and  ready  for  the  superphosphate  maker.  The 
pulp  will  soon  solidify  and  be  ready  for  manure-making.  Or  such  carcases 
might  be  treated  with  oil  of  vitriol ;  if  well  covered  with  dry  earth,  ashes,  char- 
coal, or  other  deodorant,  they  might  be  kept  for  days  without  nuisance  if  under 
a  shed.  Carcases  should  not  be  allowed  to  lie  exposed  to  the  weather,  but 
should  be  kept  under  cover  in  a  well-aerated  shed.  The  nuisance  from  the 
steam  must  be  dealt  with  by  having  a  properly  fitting  hood  to  the  boiler,  and 
conducting  the  vapours  under  and  into  the  fire,  or  by  condensing  them  in  a  cold 
shower-bath ;  the  liquor  should  not  be  run  into  the  drains  until  it  is  cold.  All 
annoyance  from  the  steaming  meat  will  be  stopped  by  placing  it  in  cold  water 
directly  it  is  taken  from  the  boiler. 

Boiling  of  Tkipe,  Ox-feet,  Teotters,  Flesh,  &c. 

The  preparation  of  these  materials  as  articles  of  human  food  involves  in 
many  cases  annoyance  to  the  neighbourhood,  in  consequence  of  want  of 
reasonable  care  and  proper  appliances,  and  hence  it  calls  for  the  supervision  of 
the  Sanitary  Authority. 

Tripe  is  the  first  stomach  (paunch)  of  the  ox  or  sheep.  It  is  usually  emptied 
of  its  contents  at  the  slaughter-house,  is  subsequently  washed  and  scalded, 
and  the  villous  membrane  is  then  scraped  off  with  a  knife  or  revolving  brush. 
The  tripe  is  then  boiled,  commonly  in  a  boiler  set  in  brickwork,  but  better  in 
a  pan  with  a  steam-jacket.  When  cooked  it  is  hung  up  to  drain  and  cool, 
and  the  liquor  is  run  off  into  the  drains.  The  fat  is  collected  for  soap- 
making.  Sometimes  the  boiling  of  trotters  and  ox-feet  is  done  in  conjunction 
with  that  of  tripe. 

Ox-feet  ( '  cowheels ' ),  if  intended  for  food,  are  first  roughly  dressed,  any 
adherent  skin  being  removed  (and  set  aside  for  glue-making  where  economy 
is  practised),  and  boiled,  the  fat  being  collected  from  the  surface  and  used  as 
an  inferior  '  neat's  foot  oil.'  Sheep's  trotters,  after  being  scalded,  have  the 
hoofs  taken  off,  and  after  removal  of  hair,  loose  skin,  &c.,  are  fit  for  boiling. 

If  not  intended  for  food,  the  ox-feet  go  through  a  careful  series  of  operations, 
so  as  to  utilise  every  part  as  far  as  possible.  In  small  works  there  is  great 
waste,  and  many  of  the  operations  here  referred  to  are  entirely  neglected  and 
the  materials  allowed  to  go  to  waste.  But  where  proper  appliances  and  skill 
are  available  the  treatment  is  briefly  as  follows  : — 

The  skins  having  been  stripped  off  are  treated  with  lime-water  to  form 
glue-pieces  {vide  Glue).  The  hoof  is  then  slit  up  between  its  divisions  and 
the  ends  of  the  two  long  bones  are  divided.  The  collection  of  soft  fat  near 
the  hoof  is  carefully  removed,  being  the  source  of  the  best  '  neat's  foot 
oil.'  The  hoof  is  then  cut  off,  washed,  and  boiled,  usually  in  pans  on  an 
open  fire.  After  boihng  for  some  three  hours  the  hoofs  are  removed,  and  set 
aside  for  the  comb-  and  button-maker,  &c.,  the  oil  which  has  been  boiled  out 
being  kept  as  an  mferior  '  neat's  foot  oil.'     The  smaller  bones  are  utilised 


902  HYGIENE 

for  manure,  tlie  larger  sliank-bones  for  knife-handles,  and  the  liquor  is  either 
further  utilised  for  whatever  oil  it  contains  or  run  into  the  drains. 

Sheep's  trotters  which  are  too  putrid  to  be  used  for  food  are  limed,  and 
then  similarly  boiled,  the  fat  being  skimmed  off  and  sent  to  the  soap-maker,, 
and  the  residue  (except  the  skin,  which  is  used  for  glue)  is  variously  disposed 
of,  the  larger  bones  to  the  bone  manufacturer,  the  smaller,  together  with  hair, 
flesh,  &c.,  to  the  manure-maker.  As  only  trotters  which  are  in  an  offensive 
state  are  used  for  this  purpose,  there  is  often  a  most  unpleasant  odour 
produced  throughout  the  place  where  the  operation  is  carried  on. 

Boiling  of  Flesh  from  Horses  and  other  Carcases 

In  most  knackers'  yards  there  exist  arrangements,  sometimes  of  a  very 
primitive  kind,  for  boiling  the  flesh  of  horses  and  other  animals  which,  from 
some  cause,  is  unfit  for  human  food,  and  utilising  it  to  make  cat's-meat,  to 
produce  grease,  &c. 

Carcases  have  to  be  disposed  of  in  considerable  numbers  in  all  large 
towns,  and  considering  that  many  of  them  are  in  a  very  offensive  state  when 
they  arrive  at  the  knackeries,  it  is  not  surprising  that  the  boiling  of  them  is 
sometimes  most  offensive.  The  worse  the  raw  material,  the  worse  the  nuisance. 

But  the  knacker's  yard  is  a  necessary  and  most  useful  institution,  and  it 
need  not  necessarily  be  a  nuisance. 

The  nuisances  emanating  from  such  places  arise  usually  from  some  or 
several  of  the  following  causes  : — • 

(1)  General  filthy  condition  of  the  premises,  owing  to  unsuitabiUty  for 
the  work,  and  want  of  care  in  carrying  it  on. 

(2)  The  accumulation  of  material  on  the  premises,  carcases  waiting  to 
be  treated,  scraped  bones  waiting  to  be  boiled,  and  bones  lying  in  heaps  after 
boiling  ;  hoofs  and  horns,  blood,  scraps  of  skin,  fat,  hair,  &c. 

(3)  The  seething  materials  just  removed  from  the  boiler  being  thrown 
on  the  ground  and  emitting  stinking  fumes  while  they  cool. 

(4)  The  fumes  from  the  boiler  in  action,  or  while  being  emptied. 

With  regard  to  (1)  it  is  absolutely  necessary,  if  such  premises  are  to  exist 
near  inhabited  localities,  that  they  must  be  suitably  constructed,  and  that 
the  business  should  be  carried  on  with  care.  The  business  is  generally  pro- 
fitable, and  all  the  nuisances  complained  of  are  associated  with  waste  and  loss 
of  money.  So  that  in  insisting  on  the  substitution,  e.g.  of  proper  steam- 
jacketed  boilers  for  open  pans  for  boiling  bones  on  the  fire,  one  may  have  the 
assurance,  in  spite  of  protests,  that  the  business  will  not  be  ruined,  but  that 
far  more  work  will  be  done  at  a  cheaper  rate,  in  a  better  manner  and  in 
a  shorter  time,  and  withal  in  such  a  way  as  to  minimise  or  abate  what 
was  a  horrible  nuisance. 

The  premises  must  not  be  too  close  to  inhabited  houses,  and  yet  they  must 
be  in  an  easily  accessible  situation,  so  that  there  may  be  no  difficulty  in  getting 
carcases  conveyed  there.  They  should  be  large  enough  for  the  amount  of  work 
to  be  done,  and  the  buildings  should  be  suitable.  Little  is  required  in  the  way 
of  buildings — there  must  be  a  good  boundary  wall,  and  there  should  be  suffi- 
cient covered  space  to  prevent  the  necessity  of  material  being  left  lymg  in  the 
open,  exposed  to  the  weather.  The  floor  should  be  smooth,  paved  with  some 
suitable  material,  and  it  should  be  well  channelled  and  drained.  The  walls 
should  be  covered  with  a  smooth  coat  of  concrete,  or  plaster,  or  glazed  brick, 
at  the  lower  part  where  there  is  Uabihty  of  their  being  splashed  with  filth.  A 
tall  chimney  is  required  with  a  good  draught,  and  the  boilers  should  be  so  con- 
structed with  hopper-hds  or  other  apphance  that  vapour  from  them  will  be  ■■ 


OFFENSIVE  BUSINESSES  QO'd 

drawn  up  the  chimney.  Where  there  is  much  boihng  done,  and  there  is  a 
hability  to  cause  a  nuisance  to  neighbouring  houses,  there  should  be  steam- 
jacketed  boilers,  or  means  for  applying  free  steam  with  a  water-jointed  lid, 
and  means  for  conducting  the  vapour  downwards  under  and  into  the  fire,  so 
as  to  burn  it  before  it  reaches  the  chimney. 

(2)  Nuisance  under  this  head  will  need  proper  covered  sheds,  with  good 
floors  ;  air-tight  buckets  for  packing  waste  which  is  to  be  removed  ;  and  above 
all  a  sufficient  staff  of  workers  to  prevent  excessive  accumulation  of  work. 

(3)  There  must  either  be  means  for  rapidly  cooling  the  meat  (cold  water, 
cool  cellaring,  &c.),  or  else  properly  closed  sheds  communicating  with  the 
chimney  by  means  of  a  good  air-shaft,  whereby  the  vapour  may  be  conducted 
away  ;  the  air-shaft  if  needful  to  be  provided  with  a  gas  jet,  or  fan,  or 
other  means  of  strengthening  the  draught  when  the  chimney  is  not  heated. 

(4)  There  is  no  difficulty  in  obviating  this  nuisance,  and  at  very  small 
expense.  There  are  various  arrangements  suitable  for  the  purpose,  whereby 
the  vapours  are  either  conducted  under  the  fire-place  and  burned,  or  passed 
into  a  tank  of  cold  water  and  condensed  (the  residual  gases  being  if  neces- 
sary conducted  under  the  fire  and  burned),  or  conducted  into  a  scrubber  or 
into  some  form  of  shower  bath,  where  rapid  cooling  and  condensation  may  be 
effected. 

Gut-cleaning 

The  small  intestines  of  pigs  ^  and  sheep  (termed  '  rops  '  in  the  North  of 
England)  are  used  for  sausage  making  and  for  making  catgut.  The 
muscular  and  mucous  layers  are  not  required  for  these  purposes,  and  their 
removal  is  the  work  of  the  gut- scraper  or  cleaner,  who  leaves  only  the 
peritoneal  covering  for  the  purposes  indicated  above.  The  guts  are  first 
cleaned  and  the  contents  evacuated  in  water  by  a  man,  or  water  is  run 
through  them  from  the  tap,  after  which  they  are  left  lying  in  salt  and  cold 
water  for  six  to  eight  days  or  longer  in  cold  weather,  and  afterwards  for  four 
to  five  days  in  plain  cold  water  until  the  tissues  have  been  so  softened  that  their 
separation  is  easy.  To  eflect  this  the  guts  are  removed  from  the  tank  and 
placed  on  a  table,  and  the  gut  is  rubbed  with  the  back  of  a  knife  or  a  piece 
of  wood,  being  passed  along  from  hand  to  hand.  It  is  then  thrown  again 
into  water. 

If  required  for  sausage  skins,  the  gut  is  then  simply  placed  in  salt.  Cat- 
gut is  made  out  of  the  guts  thus  prepared  (without  being  salted)  by  sewing 
the  ends  together  with  a  needle  and  thread,  and  spinning  them  by  an  ordinary 
spinning-wheel.  The  thickness  of  the  cat-gut  depends  on  the  number  of 
strands  of  gut  in  it.  The  strings  are  usually  bleached  by  exposure  for  two 
to  three  days  to  the  fumes  of  burning  sulphur  in  a  special  chamber,  after 
which  they  are  dried  by  being  stretched  over  pegs  in  the  open  ah%  but  pro- 
tected from  rain  and  sun. 

The  guts  are  prepared  for  spinning  by  being  steeped  in  a  weak  solution  of 
carbonate  of  sodium,  which  is  changed  twice  a  day  during  seven  to  eight  days  ; 
and  at  each  change  they  are  run  through  a  hole  formed  at  the  angle  of  a  piece 
of  bent  copper-plate. 

Places  where  gut-spinning  is  carried  on  are,  as  a  rule,  kept  in  an  exceed- 
ingly offensive  condition.  '  Eop  '-cleaning,  or  the  preparation  of  sausage 
skins,  is  also  sometimes,  but  not  so  often,  a  nuisance. 

In  the  latter  case  the  nuisance  is  usually  due  to  scraps  allowed  to  accu- 

'  The  intestines  of  the  pig  average  72  feet  in  length,  of  which  56  go  to  the  small^  and 
16  to  the  large  intestine.     The  intestines  of  the  ox  measure  about  147  feet  in  length. 


904  HYGIENE 

mulate  and  putrefy  on  the  premises,  in  order  to  have  enough  to  make  a  load 
to  send  away.  The  water  in  which  the  guts  are  kept  is  also,  at  times,  very 
cfifensive. 

The  prevention  of  such  nuisances  is  easy  enough  :  the  premises  should 
be  adapted  to  the  work,  and  be  provided  with  proper  stone  tables  and  other 
appliances ;  the  storage  of  material  for  any  length  of  time  should  be  for- 
bidden, and  what  material  is  there  should  be  kept  in  properly  covered  and 
non-absorbent  receptacles.  The  liquor  should  be  deodorised  with  chloralum 
or  chlorinated  soda,  which  may  be  used  even  when  the  guts  are  in  steep,  and 
which  obviates  putrid  fermentation.  The  disintegration  of  the  tissues  might 
be  accelerated  by  warming  the  water  to  from  80°  to  89°  F. 

The  annoyance  from  this  business  is  often  mainly  due  to  its  being  carried 
on  in  places  never  intended  for  such  work.  A  man  will  commence  sausage- 
making  in  a  small  way  in  a  private  house,  perhaps  one  of  a  row  of  workmen's 
dwellings,  without  any  yard  or  accommodation.  He  feeds  a  pig  somewhere, 
gets  it  killed  and  conveys  the  guts  to  his  house  to  prepare  the  sausage-skins, 
either  in  the  dwelling-house,  or  in  an  improvised  place  in  the  yard,  which  is 
probably  hardly  large  enougli  for  the  ordinary  purposes  of  a  dwelling-house. 
"What  wonder  if  the  neighbours  complain  in  such  a  case  as  this  !  It  should 
be  forbidden  by  law  to  carry  on  work  of  this  kind  except  on  duly  authorised 
premises. 

The  cat-gut  making  is  almost  invariably  carried  on  so  as  to  be  a 
nuisance,  the  most  horrible  stench  pervading  the  place  and  attaching  itself 
to  the  person  and  clothes  of  everyone  who  remains  in  it  even  a  short  time, 
and  spreading  to  a  considerable  distance  around  the  premises,  which  them- 
selves become  saturated  with  stench. 

Still,  there  are  many  who  will  maintain  that  health  is  not  injured  by  the 
nuisance.  It  is  no  doubt  possible  for  persons  to  become  acclimatised  to  such 
an  atmosphere,  but  for  the  average  man  it  cannot  be  regarded  as  healthy, 
and  sanitary  regulations  must  be  framed  with  a  view  to  the  average  man. 

The  building  must  be  adapted  to  the  trade,  and  be  properly  situated,  at 
a  convenient  distance  from  dwelling-houses.  The  more  offensive  work  should 
be  carried  on  in  a  closed  chamber,  with  active  artificial  ventilation,  and  an 
arrangement  for  driving  the  foul  air  through  the  fire,  so  as  to  burn  it  before  it 
escapes  into  the  atmosphere.  The  floors  should  be  constructed  of  concrete 
or  flags,  or  other  suitable  material,  and  properly  sloped  to  the  drain,  and  the 
walls  should  be  also  concreted  or  plastered  or  otherwise  rendered  impervious  to 
a  height  of  five  to  six  feet.  There  should  be  an  abundant  supply  of  water,  and 
a  hose  kept  for  swilling  the  place. 

But  nothing  will  prevent  a  nuisance  unless  care  be  continually  exercised 
to  keep  the  place  clean,  and  never  to  allow  filth  to  accumulate.  The  cleans- 
ing of  it  must  be  frequent  and  thorough. 

No  accumulations  of  stinking  material  should  be  tolerated  on  the 
premises,  and  there  should  be  proper  vessels  for  conveying  material  to  and 
from  the  place. 

Utilisation  of  Blood 
Manufacture  of  Blood  Albumen 

The  albumen  is  prepared  by  desiccating  the  serum,  from  which  the  clot 
has  been  separated.  For  the  purpose  of  this  trade  the  blood  must  be  fresh  ; 
hence  there  is  no  offensiveness  essentially  connected  with  it. 

The  serum  contained  in  the  clots  is  drained  off'  by  slicing  the  clots, 
•which  are  placed  on  a  strainer  above  a  pan,  so  situated  as  to  catch  the  serum 


OFFENSIVE  BUSINESSES  905 

as  it  oozes  from  the  contracting  clots,  a  process  which  lasts  from  twelve  to 
twenty-four  hours,  according  as  the  weather  is  hot  or  cold.  When  a  high- 
class  albumen,  free  from  colour,  is  required,  this  reddish  serum  is  transferred 
to  a  cask  and  allowed  to  stand  until  the  red  colouring  matter  has  subsided. 
Inferior,  coloured  albumen  is  prepared  by  drying  the  albumen  without  wait- 
ing for  it  to  settle.  The  drying  is  effected  in  shallow  iron  pans  placed  in  a 
room  heated  to  about  120°  F.  The  clot  is  commonly  used  for  manure- 
making. 

This  trade  is  now  commonly  carried  on  in  connection  with  large  public 
abattoirs,  and  where  there  are  space  and  cleanliness  there  is  no  nuisance. 
But  if  the  premises  be  small  and  in  a  crowded  district,  and  if  reasonable  care 
be  not  exercised,  and  especially  if  blood  from  other  sources  besides  that  from 
animals  slaughtered  on  the  premises  be  collected  and  be  utilised  for  manure- 
making,  there  may  be  complaints  of  a  nuisance.  The  complaints  are  usually 
owing  to  old  material  (clots,  &c.)  retained  on  the  premises  until  it  is  putrid, 
and  from  a  general  unpleasant  smell  which  pervades  the  place,  if  not  kept 
perfectly  clean. 

When  not  directly  used  for  manure-making,  &c.,  on  the  premises,  the 
clot  should  be  put  in  proper  air-tight  receptacles,  and  removed  as  soon  as 
possible.  It  should  never  be  allowed  to  accumulate  in  the  yard,  and  there 
should  be  no  dung-heap  on  which  to  throw  it,  except  what  may  be  collected 
from  day  to  day. 

The  premises  should  be  kept  scrupulously  clean,  especially  the  floors,  which 
should  be  of  impervious  material,  as  they  are  liable  to  be  splashed  with  blood. 
It  is  difficult  to  keep  the  divisions  between  flag- stones  thoroughly  water-tight ; 
hence  concrete  is  better.  The  yard,  too,  should  be  well  paved  and  drained. 
The  clot-room  and  the  drying-room  should  be  effectually  closed  on  all  sides, 
and  be  lighted  and  ventilated  from  the  roof.  The  most  effective  way  would 
be  to  draw  off  all  the  air  by  a  fan  into  the  furnace,  through  which  it  would 
pass  into  a  tall  chimney.  All  the  implements  and  appliances  used  in  the 
business  must  be  kept  thoroughly  clean. 

Blood  Manure 

Blood-clot  is  sometimes  utilised  by  being  mixed  with  an  acid,  usually  brown 
sulphuric  acid  (rarely  hydrochloric  acid),  desiccated,  pulverised,  and  mixed 
with  other  materials  such  as  superphosphate,  scutch  manures,  &c.  The  blood 
is  thoroughly  mixed  with  the  acid,  and  stirred  until  the  whole  is  reduced  to  the 
■consistence  of  porridge.  It  is  then  dug  out  and  allowed  to  dry  in  the  air,  which 
takes  three  to  four  days  in  summer,  and  rather  longer  in  winter.  It  musi 
of  course  be  protected  from  the  rain.  Sometimes  it  is  dried  by  artificial  heat 
on  a  floor  heated  by  steam,  which  is  much  more  Hkely  to  cause  nuisance. 
While  it  is  drying  a  certain  amount  of  red  acid  liquid  drains  off,  which  may 
be  utilised  in  the  succeeding  operations. 

Apart  from  nuisance  arising  from  filth  allowed  to  accumulate  on  the 
premises,  there  is  little  to  complain  of  in  this  business,  except  during  the 
mixing  of  the  blood  and  acid,  when  very  offensive  vapours  are  given  off, 
and  during  drying  by  artificial  heat.  The  former  operation  should  be  con- 
ducted in  a  covered  chamber,  the  vapour  from  which  should  be  conducted 
under  and  into  the  fire,  or  into  water.  The  drying  should  always  be  effected 
either  spontaneously  in  the  air,  or  by  steam,  and  never  by  direct  fire-heat, 
as  it  is  difficult  to  avoid  a  horrible  stench  fr'om  overheating  the  parts  next 
the  fire. 


906  HYGIENE 


Blood-boiliiig  and  Drying 

The  clot  from  albumen  works,  and  blood  which  has  become  too  putrid  for 
making  albumen  is  sometimes  desiccated  on  a  floor  heated  artificially,  or  in 
a  boiler  by  direct  fire-heat.  The  latter  method  is  almost  certain  to  cause  a 
nuisance,  by  over-heating  the  blood.  Whichever  process  is  used,  the  vapour 
should  be  conducted  by  a  hood  and  flue,  under  and  into  the  fire,  before  being 
discharged  into  the  air.  Or  in  some  cases  it  may  even  be  necessary  to  pass 
it  first  through  a  cold-water  condenser,  to  absorb  part  of  the  vapours  and 
gases. 

Preiiaration  of  Blood  for  Turkey -red  Dyeing 

Before  the  introduction  of  alizarin,  cotton  dyers  used  madder,  and  its 
commercial  preparation  garancine,  to  produce  the  red  colour  known  as 
turkey  red,  remarkable  for  its  brilliancy  and  fastness  both  to  light  and  boil- 
ing alkaline  solutions. 

Alizarin,  formerly  only  known  as  a  substance  obtainable  from  madder 
root,  is  now  made  in  large  quantities  from  the  coal-tar  product,  anthracene, 
and  has  almost  entirely  displaced  madder,  as  the  colours  it  produces  are  far 
more  brilhant,  quite  as  fast,  and  less  expensive.  Bullock's  blood  is  used  to 
fix  the  ahzarin  on  the  cotton,  by  the  coagulation  of  its  albumen. 

The  blood  is  prepared  first  by  collecting  the  serum  which  has  already 
separated  from  the  clot,  residual  serum  being  extracted  from  the  clot  itself 
by  placing  it  on  a  strainer  above  the  vessel  and  slicing  it,  and  subsequently 
treating  the  clot  with  water,  which  is  allowed  to  run  into  the  reservoir  with 
the  serum.  The  clot  itself  is  then  rubbed  up  with  water,  and  strained  into 
the  remainder  of  the  liquor,  and  the  whole  is  then  put  in  barrels  for  use. 

As  the  blood  is  usually  more  or  less  putrid  during  the  whole  of  these 
operations,  a  horrible  stench  is  produced,  which  may  be  perceived  a  long 
way  from  the  works. 

The  nuisance  may  be  obviated  by  conducting  the  operation  in  a  closed 
chamber  pronded  with  a  suitable  flue  to  carry  off  the  vapours  fi'om  the 
place  where  the  work  is  carried  on,  and  the  use  of  a  fan  to  convey  them 
under  and  into  a  fire,  connected  with  a  high  chimney. 

It  is  at  the  same  time  essential  that  scrupulous  cleanliness  be  observed 
on  the  premises,  that  the  floor  be  constantly  cleansed  from  all  blood  which 
has  fallen  on  it,  and  that  all  the  utensils  be  kept  sweet.  The  place  where 
the  work  is  carried  on  must  be  well  closed  in,  and  not  exposed  to  the  action 
of  the  wind,  or  else  the  ventilating  fan  cannot  act  effectively. 

The  following  is  an  abstract  of  the  bye-laws  framed  by  the  London 
County  Council,  under  the  Slaughterhouses  &c.  (Metropolis)  Act,  1874, 
for  the  regulation  of  the  business  of  a  blood  drier,  and  any  business  m  which 
blood,  or  any  constituent  parts  of  blood,  is  used,  provided  that  heat  be  in  any 
way  applied  or  used  to  the  same  : — 

1.  Every  blood  drier  shall  cause  all  blood  brought  upon  his  premises  to  be  brought 
in  closed  vessels  or  receptacles  constructed  of  galvanised  iron  or  other  non-absorbent 
material. 

2.  Every  blood  drier  shall  cause  every  process  of  his  business  (except  the  drying 
and  packing  processes  to  be  carried  on  in  a  building  properly  paved  with  asphalte, 
concrete,  or  other  suitable  jointless  material,  having  walls  covered  to  the  height  of  at 
least  six  feet,  with  hard,  smooth,  and  impervious  material. 

3.  Every  blood  drier  shall  cause  every  process  of  his  business  in  which  any  offensive 


OFFENSIVE  BUSINESSES  907 

effluvia,  vapours,  or  gases  are  generated,  to  be  carried  on  in  such  manner  that  no  offensive 
effluvia,  vapours,  or  gases  shall  escape  into  the  external  atmosphere ;  and  he  shall  cause 
all  such  offensive  eflluvia,  vapours,  or  gases  to  be  eflectually  destroyed. 

4.  Every  blood  drier  shall  cause  all  blood,  blood-clot,  or  any  refuse,  residue,  or  other 
matter  from  which  offensive  effluvia  or  vapours  are  evolved,  or  are  liable  to  be  evolved, 
to  be  placed  in  properly  closed  receptacles,  or  to  be  otherwise  dealt  with  in  such 
manner  as  to  prevent  any  offensive  efHuvia  or  vapours  therefrom  escaping  into  the 
external  atmosphere. 

5.  Every  blood  drier  shall  cause  the  floor  of  every  place  in  which  any  process  of  the 
business  (except  the  drying  and  packing  processes)  is  carried  on  to  be  thoroughly  cleansed 
with  water  at  least  once  in  twenty-four  hours  ;  and  he  shall  cause  the  premises  to  be 
constantly  provided  with  an  adequate  supply  of  water  for  the  purpose. 

6  Provides  for  the  periodical  cleansing  of  the  premises,  and  7  provides  for  the  due 
and  frequent  cleansing  of  the  vessels  used. 

11.  Every  blood  drier  shall  cause  the  floor  of  the  yard  and  every  part  of  his  premises 
in  which  any  process  of  his  business  (except  the  drying  and  packing  processes)  is  carried 
on,  to  be  properly  paved  with  asphalte,  concrete,  or  other  suitable  jointless  material, 
laid  upon  a  suitable  bottom  of  at  least  four  inches  in  thickness,  and  such  floor  to  have  a 
proper  slope  towards  a  channel  or  guUey ;  and  shall  cause  his  premises  to  be  effectually 
drained  by  adequate  drains  communicating  with  a  public  sewer.  The  drains  shall  be 
properly  trapped,  and  the  entrances  thereto  shall  be  covered  with  fixed  gratings,  the 
bars  of  which  shall  not  be  more  than  three-eighths  of  an  inch  apart. 

13.  Every  blood  drier  shall  cause  his  premises  to  be  provided  with  appliances 
capable  of  effectually  destroying  all  offensive  effluvia,  vapours,  or  gases  arising  in  any 
process  of  his  business,  or  from  any  material,  residue,  or  other  substance  which  may 
be  kept  or  stored  upon  his  premises. 

PISH-FEYING 

The  frying  of  fish  for  sale,  ready-cooked,  is  a  business  that  gives  rise  to 
many  complaints.  The  trade  exists  almost  entirely  for  the  poorer  class, 
and  hence  the  shops  are  usually,  but  by  no  means  invariably,  situated  in 
poor  thickly  populated  streets.  The  complaints  do  not  generally  come  from 
the  poor  for  whom  the  trade  is  carried  on,  but  from  persons  living  at  a 
little  distance,  whom  the  effluvia  from  the  chimney  may  reach,  or  from 
persons  who  are  in  the  habit  of  frequently  passing  the  premises. 

The  smell  is  often  very  unpleasant.  The  nuisance  is  sometimes  intensi- 
fied by  the  continued  use  for  a  considerable  time  (many  weeks)  of  oil  in 
which  fish  is  constantly  being  cooked. 

The  cookmg  commonly  consists  in  ordinary  frying,  when  the  oil  is  in  a 
constant  state  of  effervescence  [the  oil  itself  being  rarely  boiled ;  it  is  the 
water  in  it  which  is  raised  to  boiling  point,  and  causes  the  phenomenon 
commonly,  but  erroneously,  called  'boiling].'  Particles  of  the  oil  escape, 
with  bubbles  of  water  escaping  from  it,  and  spread  the  smell,  and  as  the  oil, 
as  well  as  part  of  the  fish  are  usually  partially  burned  from  the  cooking 
on  the  open  fire,  strong  empyreumatic  odours  are  produced. 

If  oil  at  a  high  temperature  were  used,  as  is  so  common  m  France,  to 
cook  the  food  at  a  high  temperature  (without  the  food  itself  being  browned 
or  burned  by  actual  contact  with  the  hot  pan),  the  cooking  would  be  much 
more  effective,  and  it  would  make  the  food  much  more  palatable,  and  at  the 
same  time  the  burning  which  causes  much  of  the  nuisance  would  be  avoided. 

The  fact  that  the  cooking  is  usually  carried  on  on  the  open  fire,  in  the 
open  shop,  and  subject  to  draughts  of  wind,  causes  the  effluvia  to  be  blown, 
about  in  all  directions. 

The  use  of  a  deep  vessel  of  oil  (six  to  ten  inches  of  oil  according  to  re- 
quirements), kept  at  a  high  temperature,  in  which  the  fish  could  be  cooked, 
without  burning,  and  the  addition  of  a  hopper  above  to  carry  off  the  effluvium 
into  a  high  chimney,  will  generally  put  a  stop  to  all  nuisance.     A  good  gas- 


908  HYGIENE 

burner  may  be  required  to  increase  the  draught  up  the  pipe  from  the  hopper. 
The  cliimney  must  be  high  enough  to  conduct  the  vapours  above  neiglibouring 
houses.  If  further  steps  are  required,  the  vapours  may  be  conducted  under 
the  fire,  and  obhged  to  pass  through  it,  which  will  lead  to  their  combustion, 
or  they  may  be  conducted  through  water.  After  washing  the  vapour  there 
seldom  remains  any  offensive  smell. 

The  cooking  vessel  should  also  be  provided  with  a  well-fitting  lid,  which 
can  be  easily  raised  and  lowered,  and  provided  with  a  suitable  opening  to 
enable  the  cook  to  inspect  the  interior  at  will. 


GLUE 

This  important  article  is  made  from  almost  every  kind  of  waste  animal 
tissue  ;  it  is  chiefly  obtained  from  bones  (after  the  fat  has  been  extracted  by 
boiling),  hoofs,  horns,  scraps  cut  off  during  the  preparation  of  skins  for 
leather,  scraps  of  leather,  parchment,  &c.  The  raw  material  which  hag 
not  already  been  limed  (leather  is  differently  treated)  is  first  limed,  and  then 
washed,  boiled,  and  stirred  for  some  hours  in  a  vessel  with  a  false  per- 
forated bottom  (to  keep  the  material  from  burning  at  the  bottom).  The  thick 
fluid  is  drawn  off  after  it  has  cooled,  and  is  allowed  to  settle  into  a  second 
receptacle,  where  it  continues  to  stand  and  further  clear.  The  use  of  super- 
heated steam  is  a  great  improvement  on  this  method,  giving  a  better  return 
in  a  shorter  time.  After  a  time  the  liquor  is  drawn  off  into  wooden  boxes,  about 
14  ft.  X  12  in.  X  9  in.  deep,  in  which  it  cools  in  the  course  of  twelve  to 
eighteen  hours.  The  glue  is  then  removed  from  the  boxes,  placed  in  wooden 
frames  and  cut  into  slices  to  dry,  during  which  latter  process  it  shrinks  to 
about  half  its  bulk. 

When  scrap  leather  is  used  it  is  treated  with  slaked  lime  and  water  at  a 
high  temperature  (about  250°  F.)  By  this  means  the  leather  is  decomposed, 
the  tannin  combines  with  lime,  and  the  gelatine  becomes  dissolved  in  the 
water.     Glue  made  in  this  way  is  of  inferior  quality. 

Glue  which  has  become  foul  during  preparation  has  the  curious  and  un- 
pleasant property  of  recovering  its  evil  odour  long  afterwards,  when  in  use 
on  walls,  wood,  &c.,  if  it  becomes  moist.  Size  is  made  in  the  same  way  as 
glue,  only  from  better  material  and  with  more  care  ;  it  may  be  cheap  and 
little  superior  to  glue  in  quality,  or  of  very  superior  quality,  such  as  is 
used  for  making  gelatine  and  isinglass.  It  is  sold  both  in  the  solid  and 
liquid  form.  The  latter  is  commonly  nothing  but  a  very  dilute  solution  of 
glue.  But  a  cheaper  and  better  article  is  now  largely  used,  made  from 
powdered  resin  dissolved  in  a  warm  aqueous  solution  of  soda. 

The  manufacture  of  glue  is  often  attended  by  great  nuisance,  though  not 
necessarily  so.  The  nuisance  most  frequently  complained  of  is  the  smell 
from  the  hot  pans.  The  character  of  the  material  used  has  a  great  deal  to 
do  with  the  nuisance,  old  foul  scraps  causing  a  penetrating,  acrid  odour,  very 
different  from  that  arismg  from  good  fresh  material.  Besides  this  effluvium, 
nuisance  may  arise  from  the  general  filth  of  a  badly  managed  place,  where 
decomposing  organic  matter  is  allowed  to  collect  on  the  ground,  or  to  adhere 
to  the  walls  and  the  thousand  places  where  dirt  can  accumulate.  The  debris 
from  the  vats,  after  the  glue  has  been  drawn  off,  commonly  known  ag 
'  scutch,'  is  a  fruitful  source  of  nuisance  when  allowed  to  accumulate.  The 
sooner  it  is  barrelled  and  removed  the  better.  Should  delay  unavoidably 
occur  in  doing  this,  the  scutch  will  be  best  kept  in  a  dry,  airy  place ;  for 
it  is   very  likely  to  putrefy  and  become  offensive  if  kept  exposed  to  the 


OFFENSIVE  BUSINESSES  909 

vicissitudes  of  our  climate.  Carbolic  powder  sprinkled  over  it  is  a  useful 
protective. 

There  is  often  mucli  nuisance  produced  by  accumulations  of  raw  material 
on  the  premises  before  use.  This  may,  without  injury,  and  with  the  best 
prospect  of  avoidance  of  nuisance,  be  stacked,  each  layer  of  a  few  inches 
thick  being  well  covered  with  milk  of  lime.  This  material  must  not  be 
exposed  to  damp,  otherwise  putrefaction  and  stench  (as  well  as  destruction 
of  valuable  material)  must  certainly  ensue. 

The  stench  from  the  boiling  process  is  always  worst  where  open  fires  are 
used ;  hence  heating  by  steam  is  to  be  recommended  as  a  preventive,  and  as 
probably  a  more  economical  method.  The  vapour  may  be  conducted  under 
and  into  the  fire,  and  burned,  or  into  a  scrubber,  where  it  would  be  washed 
and  condensed.    It  should  always  be  at  last  conducted  into  a  tall  chimney. 

The  after-treatment  of  the  '  scutch,'  to  remove  the  fat  from  it,  deserves 
notice.  It  is  usually  treated  with  hot  water,  or  cold  water  with  steam,  and 
the  fat  skimmed  off,  the  residue  being  pressed  in  coarse  canvas  to  extract  the 
last  remnants  of  grease.  The  cake  is  used  for  manure.  If  kept  dry  and  under 
cover,  it  will  keep  inoffensive  for  some  time;  but  if  allowed  to  accumulate 
in  the  open  air,  it  soon  becomes  offensive. 


EECOVEEING  GEEASE  FEOM  SOAP  SUDS' 

In  districts  where  the  manufacture  of  wool  is  carried  on  there  is  often' 
annoyance  caused  by  the  warm  suds  produced  in  washing  the  wool,  some 
kinds  of  which  are  very  greasy  ;  as  well  as  by  the  efforts  to  utilise  the 
wool-fat  ('  suint ')  and  the  large  quantities  of  soap  which  are  employed  in 
the  washing. 

This  was  at  one  time  a  large  and  profitable  business,  but  for  some  years 
past  has  declined.  In  many  large  wool  works  the  grease  is  recovered  and 
converted  into  soap  on  the  premises,  and  one  lot  of  wool  is  actually  washed- 
with  soap  extracted  as  an  impurity  out  of  a  preceding  lot. 

But  some  persons  make  a  special  business  of  recovering  the  grease,  and 
for  this  purpose  collect  the  suds  from  several  wool-washing  places.  The 
liquid  is  roughly  strained  as  it  passes  into  a  large  tank  (v/hich  is  sometimes 
heated  by  steam),  when  sulphuric  acid  is  added,  and  mixed  with  it  in 
sufficient  excess  to  slightly  acidify  the  liquor.  The  acid  combines  with  the 
soda,  potash,  and  other  alkalies  present  in  the  soap  and  wool-fat,  and  the 
grease  being  set  free  rises  to  the  top  as  a  dirty  scum  known  as  '  magma.' 
The  liquor  is  then  run  off  from  the  bottom,  usually  direct  into  the  drain, 
and  the  magma  is  either  collected  directly  on  coarse  canvas,  through  which 
it  drains,  or  it  is  removed  and  allowed  to  drain  in  a  hole  in  the  ground  m 
the  open  air.  Afterwards,  and  while  still  wrapped  in  the  canvas  (called 
'  bags '),  it  is  put  in  a  press  and  is  squeezed  while  heated  by  steam.  The 
grease  and  some  water  and  dirt  escape  from  the  bottom  into  a  tank,  where 
the  grease  again  separates  and  floats,  and  is  ladled  out  into  a  vessel,  in 
which  it  is  again  treated  with  sulphuric  acid  to  remove  the  water,  after  which 
it  is  put  in  barrels  for  sale  either  to  be  further  purified  or  to  be  used  for 
common  work.  The  residue  in  the  '  bags  '  is  commonly  used  as  manure,  or 
thrown  away.  Sometimes  it  is  further  treated  with  bisulphide  of  carbon, 
and  a  profitable  business  may  be  done  in  recovering  the  residue  fat  by  this 
interesting  process.  The  cake  to  be  treated  is  first  ground  in  a  mortar-mill 
and  then  placed  in  a  cylinder  containing  the  bisulphide,  which  dissolves 
'  Cf.  Article  on  Manufacture  of  Soap,  p.  912. 


910  HYGIENE 

every  trace  of  fat.  Steam  is  then  let  into  the  cylinder  and  separates  the  two, 
the  fat  being  run  off  by  one  tap  and  the  bisulphide  retained  to  be  used  over 
again.  There  is  but  small  loss  of  bisulphide  at  each  operation,  and  this  is 
made  good  by  the  necessary  addition  of  more,  and  the  process  is  kept  in 
constant  operation. 

This  process  is  exceedingly  dangerous,  owing  to  the  inflammable  nature 
of  the  bisulphide.  No  light  must  be  burned  inside  the  building  where  it  is 
used.  The  plan  adopted  is  to  have  the  chamber  where  the  operation  is 
carried  out  carefully  boarded  off,  the  partition  having  windows  in  it,  outside 
of  which  are  placed  the  gas-lights.  This  bisulphide  process  is  carried 
on  at  Frizinghall,  a  suburb  of  Bradford,  Yorks.,  without  the  shghtest 
nuisance. 

The  nuisance  complained  of  in  treatmg  the  suds  is  from  offensive  smells, 
due  to  putrefaction  from  over-keeping.  This  can  only  be  prevented  by  the 
avoidance  of  this  unnecessary  practice.  The  warming  of  the  suds  by  steam 
accelerates  the  work,  and  the  adoption  of  this  plan  would  undoubtedly  assist 
in  getting  rid  of  objectionable  material  more  rapidly  and  preventing  nuisance. 
The  press  is  also  liable  to  cause  offensive  smells,  but  only  to  a  shght 
extent,  and  chiefly  in  hot  weather.  The  discharge  of  the  acid  liquor  into 
the  sewer  is  alleged,  but  hardly  on  sufficient  grounds,  to  greatly  increase  the 
evolution  of  offensive  gases  (sulphuretted  hydrogen)  from  the  sewers.  When 
the  liquor  smells  offensively,  it  may  be  deodorised  by  the  addition  of  proto- 
sulphate  of  iron  (about  20  lb.  of  the  salt  to  1,000  gallons  of  the  liquor). 

DIP-CANDLE-MAKING.     PAT-MELTING 

These  associated  processes  are  still  carried  on  in  almost  all  large  towns, 
notwithstanding  the  general  use  of  gas,  illuminating  oils  for  lamps,  and  the 
immense  trade  in  candles  from  wholesale  manufacturers,  which  the  great 
cheapness  of  traffic  allows  to  be  retailed  in  the  smallest  village  at  a  moderate 
price. 

Fat-melting  is  required  for  the  purpose  of  making  soap,  waggon-grease, 
candles,  and  other  purposes.  The  materials  used  are  chiefly  beef,  mutton, 
and  pig  fat,  kitchen-waste,  dripping,  fat  collected  from  plates  and  dishes, 
and  waste  meat ;  also  the  scraps  of  meat,  fat,  &c.,  collected  by  itinerant 
rag-and-bone  men,  and  not  mfrequently  inferior  stuff'  obtained  from  the 
boiling  down  of  bones  and  scraps  at  knacker-yards,  tripe-  and  glue-boiling 
works,  &c. 

Tallow  is  either  mutton  or  beef  fat,  or  a  mixture  of  both,  usually  prepared 
by  heating  crude  fat  in  contact  with  water  or  steam  until  the  membranous 
covering  in  which  the  fatty  matter  is  encased  swells  and  bursts  ;  after  the 
whole  has  cooled,  the  membranous  covering  is  found  between  the  water  and 
the  superjacent  tallow.  Lard  is  pig's  fat  similarly  freed  from  its  membranous 
covering.  '  Moulds,'  i.e.  candles  shaped  in  moulds,  are  made  of  mutton  suet. 
'Dips,'  or  inferior  candles,  are  made  by  dipping  a  wick  into  the  molten 
fat,  made  from  inferior  tallow,  and  repeating  the  process  until  the  candle  is 
sufficiently  thick. 

Chevreuil,  who  carefuUy  investigated  the  subject  of  the  chemistry  of  fats, 
has  shown  that  the  ordinary  commercial  neutral  fats  are  to  be  regarded  as 
chemical  '  salts,'  in  which  glycerine  forms  the  base  in  combination  with  one 
of  various  fatty  acids.  When  a  neutral  fat  is  boiled  or  '  rendered,'  in  the 
ordinary  way  along  with  soda,  lime,  or  other  strong  alkali,  the  latter  displaces 
the  glycerine  and  combines  with  the  fatty  acids,  forming  a  soap. 

When,  as  happens  in  certain  processes,  the  soap  is  '  broken '  by  the 


OFFENSIVE  BUSINESSES  911 

addition  of  a  strong  mineral  acid,  e.g.  sulphuric,  the  latter  combines  with  the 
alkali,  and  the  fatty  acids  are  set  free. 

The  usual  mode  of  melting  fats,  derived  from  the  various  sources  men- 
tioned above,  is  simple  in  the  extreme  :  the  fat  is  placed  in  a  pan,  usually  set 
in  brickwork  over  an  open  fire,  and  is  stirred  from  time  to  time. 

When  '  raw '  fat  direct  from  the  carcase  has  to  be  melted  it  is  usual 
to  chop  it  up  to  facilitate  the  melting,  and  thus  in  some  degree  to  obviate  the 
danger  of  burning  it ;  but  when  it  is  treated  with  sulphuric  acid  and  steam 
it  is  rarely  chopped.  When  steam  is  used  direct,  it  is  conducted  by  a  pipe 
down  to  the  bottom  of  the  boiler  filled  with  fat. 

The  melted  tallow  is  either  run  off  through  a  tap,  or  ladled  out  by  hand 
into  a  vessel  in  which  it  is  allowed  to  settle  ;  it  is  advantageous,  but  excep- 
tional, to  ladle  it  through  a  strainer. 

The  residue,  after  all  the  tallow  has  been  removed,  consisting  of  scraps  of 
membranes  of  various  kinds,  sinew,  skin,  &c.,  is  with  advantage  squeezed 
through  a  press  to  extract  all  remnants  of  fat,  and  the  remaining  solids, 
known  as  *  greaves,'  are  commonly  used  for  manure,  or,  if  of  better  kind,  as 
food  for  animals. 

Apparatus  of  various  kinds  has  been  devised  for  the  rendering  of  lard  to 
make  the  process  more  expeditious  and  economical.  In  some  methods  these 
objects  have  been  successfully  combined  with  the  suppression  of  nuisance. 

The  great  secret  in  preventing  nuisance  is  the  avoidance  of  burning  the 
materials,  or  even  raising  them  to  a  high  temperature.  The  lower  the 
temperature  at  which  the  work  can  be  successfully  carried  on,  the  less  is  the 
risk  of  the  production  of  offensive  smells.  The  temperature  need  not  exceed 
about  120°  F.  It  is  in  summer  weather  that  nuisance  is  most  complained  of ; 
the  time  when  most  people  are  liable  to  feel  easily  annoyed  by  even  the  smells 
of  ordinary  domestic  cooking.  '  Heavy '  damp  weather,  too,  is  likely  to  make 
the  smells  hang  about  the  neighbourhood  and  cause  offence. 

The  fresher  and  sweeter  the  materials  used,  the  less  is  the  danger  of 
nuisance  during  the  melting.  A  little  care  in  keeping  the  fresh  materials 
would  often  prevent  loss  and  nuisance  ;  a  cool,  well-aerated  room  is  the  best 
place  to  keep  it  till  wanted.  The  general  principles  of  preventing  nuisance 
from  this  trade  are  the  same  as  those  mentioned  in  the  sections  on  tripe- 
boiling,  &c.  The  nuisance  arising  from  the  pressing  of  the  '  greaves  '  is 
sometimes  rather  troublesome  to  overcome,  but  by  conducting  the  operation 
under  cover,  the  whole  apparatus  being,  if  necessary,  boxed  in,  and  by 
operating  in  a  closed  room  where  there  is  a  good  draught  into  the  chimney, 
all  nuisance  may  be  completely  suppressed. 

Unless  fat-melters  will  adopt  proper  precautions,  they  should  be  obliged 
to  remove  from  populous  districts. 

General  cleanliness,  the  use  of  good  material,  melting  at  a  low  tempera- 
ture, and  the  use  of  steam  and  acid  are  the  cardinal  points  to  be  attended  to 
with  a  view  to  conducting  this  business  without  nuisance. 

The  following  are  extracts  from  the  bye-laws  in  force  for  the  regulation  of 
these  businesses  in  the  metropolis : — 

1,  Every  fat  melter  or  fat  extractor  shall  cause  every  process  of  his  business  in  which 
any  offensive  eifluvia,  vapours,  or  gases  are  generated  to  be  carried  on  in  such  manner 
that  all  offensive  efauvia,  vapours,  or  gases  shall  be  effectually  destroyed. 

2.  Every  fat  melter  or  fat  extractor  shall  cause  all  material  used  or  offensive  material 
or  refuse  from  the  boiling  pans,  and  all  refuse,  residue,  or  other  matters  from  which 
offensive  effluvia,  vapours,  or  gases  are  evolved,  or  are  liable  to  be  evolved,  to  be  placed 
in  properly  closed  receptacles,  or  to  be  otherwise  dealt  with  in  such  manner  as  to  prevent 
any  offensive  effluvia,  vapours,  or  gases  therefrom  escaping  into  the  external  atmosphere. 


912  HYGIENE 

3.  Every  fat  melter  or  fat  extractor  shall  cause  all  scraps  or  litter  composed  of  matters 
liable  to  become  decomposed  to  be  constantly  gathered  or  swept  up  and  placed  in  properly 
covered  receptacles. 

4.  Every  fat  melter  or  fat  extractor  shall  cause  the  floor  of  every  place  in  which 
any  process  of  the  business  is  carried  on  to  be  kept  thoroughly  cleansed,  and  he  shall 
cause  the  premises  to  be  constantly  provided  with  an  adequate  supply  of  water  for  the 
purpose. 

5  Orders  the  proper  and  periodical  cleansing  of  the  premises,  and  6  the  due  cleansing 
of  the  premises. 

10.  Every  fat  melter  or  fat  extractor  shall  cause  every  floor  upon  which  any  process 
of  his  business  is  carried  on,  in  any  part  of  his  premises,  to  be  properly  covered  with 
a  layer  of  concrete,  or  other  suitable  jointless  impervious  material,  laid  (in  the  case  of 
a  ground  floor)  upon  a  suitable  bottom  of  at  least  four  inches  in  thickness.  He  shall 
cause  every  such  floor  to  have  a  proper  slope  towards  a  channel  or  gulley,  and  shall 
cause  every  part  of  his  premises  wherein  any  such  floor  may  be  constructed  to  be 
effectually  drained  by  adequate  drains  communicating  with  a  public  sewer.  He  shall 
also  cause  every  drain  to  be  properly  trapped,  and  the  entrance  thereto  to  be  covered  with 
a  fixed  grating,  the  bars  of  which  shall  not  be  more  than  three-eighths  of  an  inch  apart. 

11.  Every  fat  melter  or  fat  extractor  shall  cause  his  premises  to  be  provided  with 
appliances  capable  of  effectually  destroying  all  offensive  effluvia,  vapours,  or  gases  arising 
in  any  process  of  his  business,  or  from  any  material,  residue,  or  other  substance  which 
may  be  kept  or  stored  upon  his  premises. 

MANUFACTUEE   OF   SOAP' 

This  business  has  a  sanitary  interest,  not  so  much  on  account  of  the  soap 
itself  as  of  the  fats  from  which  it  is  usually  made,  and  the  melting  of  which 
is  often,  though  by  no  means  necessarily,  a  source  of  nuisance. 

The  ordinary  neutral  fats  must  chemically  be  regarded  as  '  salts,'  i.e.  a 
combination  of  a  base  with  an  acid,  glycerine  being  the  base,  and  a  fatty 
acid  the  acid.  In  soap-making,  saponification,  i.e.  in  the  chemical  actions 
resulting  from  the  interaction  of  an  alkali  (soda,  potash,  &c.)  and  a  neutral 
fat  (tallow,  &c.),  the  glycerine  is  displaced  as  the  base,  and  its  place  is  taken 
by  the  alkali. 

Although  it  is  theoretically  true  that  all  combinations  of  fatty  acids 
with  a  mineral  base  form  soaps,  in  practice  we  need  only  consider  those 
which  are  found  with  soda  and  potash,  as  these,  being  soluble  in  water, 
are  the  only  ones  used  for  detergent  purposes. 

Soaps  are  divided  into  two  classes,  '  hard '  and  '  soft,'  according  to  their 
physical  characters.  Soft  soap  almost  invariably  has  potash  as  its  base,  and 
as  it  retains  moisture,  and  absorbs  it  from  the  air,  it  is  soft  and  pulpy, 
while  soda  soap,  or  '  hard '  soap,  dries  and  becomes  hard  in  the  air. 

Fats  of  all  kinds  are  used,^  chiefly  tallow,  either  pure  butcher's  tallow,  or 
that  collected  in  the  treatment  of  skins,  trotters,  bone-boiling,  and  glue- 
making,  also  kitchen  refuse,  grease  from  wool-washing,  &c.  What  may  be 
termed  the  natural  '  mottled  '  soap  is  due  to  decomposition  of  small  portions 
of  the  soap  owing  to  the  unavoidable  presence  of  negligible  quantities 
of  impurities,  e.g.  metallic  oxides  and  earths.  These  form  corresponding 
quantities  of  insoluble  soaps,  which  are  diffused  throughout  the  general 
body  of  the  material  durmg  '  boiling  '  and  produce  the  mottling.  Slight  im- 
purities in  the  fat  itself  cause  a  similar  effect.  Blue,  grey,  and  red  mottled 
soaps  are  modern  devices  to  please  the  eye  only.  These  soaps  are  silicated, 
i.e.  made  with  soluble  silicates  of  sodium  and  potassium  ;  the  blue  motth'ng 

'  Cf.  Article  on  Eecovery  of  Grease  from  Suds,  p.  909. 

-  Soap  is  also  made  from  rosin  (the  kind  known  as  colophony),  which  regarded 
chemically  is  an  acid,  which  combines  with  the  caustic  alkali  when  added  to  carbonate  of 
soda.     It  is,  however,  always  used  for  soap  in  combination  with  fats. 


OFFENSIVE  BUSINESSES  915 

is  produced  by  admixture  of  artificial  ultramarine,  grey  by  finely  levigated 
oxide  of  manganese. 

The  soap  is  usually  made  in  large  iron  pans,  set  in  brickwork,  in  which 
the  fat,  oil,  or  mixture  of  both  is  placed,  and  heated  either  directly  by  fire 
or,  better,  by  free  steam  (i.e.  discharged  directly  into  the  pan)  or  by  inpes 
heated  by  steam.  A  little  of  the  fat  is  first  introduced,  then  some  weak 
caustic  lye  (sp.  gr.  1'05  to  1"08) ;  the  mixture  is  well  stirred,  and  then  more 
lye  of  a  greater  strength  is  added,  and  then  more  fat,  and  more  lye,  the  boiling 
being  continued  until  the  materials  have  been  introduced  in  proper  propor- 
tions. The  whole  is  carefully  stirred,  and  samples  are  withdrawn  from  time 
to  time  for  examination.  By  the  addition  of  common  salt  (about  10  lb.  to 
100  of  fatty  matter)  the  soap  is  separated  from  the  Hquor  in  the  vessel 
(being  insoluble  in  strong  saline  solutions)  and  floats  nearly  dry  and  pure 
on  the  liquor.  At  this  stage  either  the  liquor  is  run  off  from  below,  or  the 
soap  is  drawn  off  from  the  top.  The  soap  is  again  treated  with  alkali  and 
heated,  and  after  the  liquor  has  been  run  off  it  is  placed  in  frames  of  suit- 
able size,  in  which  it  cools  and  sets,  after  which  it  is  cut  by  means  of  wires 
drawn  through  it  into  bars  or  blocks.  It  usually  contains  a  slight  excess  of 
alkali. 

Soft  soap  is  made  on  the  same  principle  as  hard,  potash,  as  already  ex- 
plained, being  the  base  used  instead  of  soda.  The  potash  is  boiled  with  linseed,, 
cotton,  whale,  fish  or  other  oil,  alone,  or  mixed  with  other  oils  or  some  tallow 
(which  gives  a  speckled  appearance).  A  weak  lye  is  added  and  well  stirred 
with  the  oil,  forming  a  viscous  compound.  Stronger  lye  is  then  added,  and 
the  boiling  is  continued,  excessive  foaming  being  prevented  by  breaking  up  the 
foam  as  it  forms  until  the  soap  has  attained  the  proper  degree  of  viscidity 
and  transparency.  This  soap  contains  all  the  '  liquor '  used  during  its 
manufacture,  as  it  is  not  separated  by  salting,  as  described  above. 

The  offensiveness  arising  from  this  manufacture  is  practically  Hmited  to 
the  manipulation  of  the  fats.  Some  kinds  of  oil  when  heated  are  very  un- 
pleasant in  smell,  especially  common  kinds  of  fish  oil.  So,  too,  is  some  of 
the  fat  obtained  from  ships'  cooking-galleys,  and  even  kitchen  stuff  and 
butcher's  fat  is  not  always  fresh,  and  indeed  the  melting  of  fats  is  generally 
unpleasant,  unless  conducted  with  care. 

Nuisance  from  these  causes  can  be  obviated  by  conducting  the  melting 
at  the  lowest  possible  temperature,  by  using  pans  or  boilers  with  properly 
fitting  lids,  connected  by  a  pipe  with  the  chimney,  or,  if  need  be,  by  con- 
ducting the  vapours  under  and  into  the  fire  or  into  water,  the  lid  of  the  pan 
having  a  door  through  which  the  boiling  can  be  superintended.  The  pre- 
cautions same  as  those  required  for  fat-rendering. 

BONE-BOILING 

Bone-boiling  is  carried  on  either  for  the  extraction  of  fat  and  gelatine,  or 
for  the  ulterior  utilisation  of  the  bones  themselves,  or  with  both  objects  in  view. 

Bones  from  knackers'  yards,  butchers'  shops,  refuse  bones  collected  by 
'  rag-and-bone  men,'  bones  from  animals  which  have  been  killed  or  have 
died,  &c.,  are  collected  at  the  bone-boiler's,  and  there  treated. 

The  '  raw  '  material  varies  from  perfectly  fresh  to  foul  and  stinking 
material,  and  the  character  of  the  effluvium  evolved  in  the  manufacture 
depends  largely  on  the  freshness  or  putridity  of  the  material  used.  The 
bones  are  generally  roughly  broken  up,  to  allow  any  marrow  to  be  readily 
boiled  out.     The  boiling  is  usually  done  in  open  iron  boilers,  set  in  brick, 

VOL.  I.  3  N 


D14  HYGIENE 

and  is  done  under  cover  or  in  the  open  air.  The  heat  is  appHed  either 
by  open  fire  or  by  steam,  and  the  operation  is  continued  until  it  is 
thought  all  the  fat  is  extracted,  which  in  inferior  boilers  will  take  five 
to  twelve  hours,  and  then  the  fat  is  skimmed  off,  and  the  bones  are  commonly 
thrown  on  the  ground  to  cool,  during  which  cooling  process  very  offensive 
efflu\'ium  is  frequently  given  off.  If  size  is  to  be  extracted  the  boihng  is 
prolonged  for  four  to  five  days  and  nights.  In  larger  works  there  is  often  a 
closed  chamber,  called  a  '  bone  hole,'  into  which  the  bones  are  thrown  and 
left  till  cool.  If  bones  of  a  superior  kind  are  under  treatment  they  are 
generally  thrown  into  cold  water  to  cool,  so  as  to  preserve  their  colour  and 
quality,  and  make  them  fit  for  making  buttons,  handles  for  knives,  small 
spoons,  &c.  Superheated  steam,  at  about  28G°  F.,  will  thoroughly  extract 
every  particle  of  fat  from  a  charge  of  bones  in  less  than  an  hour ;  but  the 
bones  are  subsequently  only  fit  for  manure. 

The  liquor  from  bones  which  have  only  been  boiled  for  a  short  time,  to 
extract  the  fat,  is  usually  discharged  direct  into  the  nearest  drain  or  stream, 
at  a  temperature  which  must  be  below  80°  F. ;  but  when  the  boiling  has  been 
continued  with  a  view  to  size-making,  the  hquor  is  further  boiled  and  con- 
densed to  a  proper  consistency,  after  which  it  is  barrelled  for  sale. 

The  process  is  a  common  source  of  complaints  arising  from  the  offensive 
effluvium.  The  fact  that  the  process  may  be  continued  for  so  long  as  four 
to  five  days,  when  size  is  made,  is  liable  to  make  it  unpleasant  to  neighbours, 
even  where  the  smell  is  not  what  may  be  termed  a  very  offensive  one.  But 
the  unceasing  smell  of  cooldng,  even  of  the  finest  kind,  in  a  private  kitchen 
finally  becomes  unpleasant  to  most  persons.  And  at  best  the  mawkish  smell  of 
meat-boiling  without  salt  is  not  pleasant.  The  presence  of  even  a  little  salt 
makes  the  odour  much  less  unpleasant  in  ordinary  meat-boiling,  but  it  would 
not  be  possible  to  use  it,  some  say,  in  bone-boiling.  But  when  putrid  bones 
are  boiled,  the  evil  is  enormously  aggravated,  and  reaches  a  maximum  in  hot 
or  close  weather. 

This  effluvium  is  to  be  treated  like  that  arising  during  fat-boiling,  &c. 
The  importance  of  a  sufficiently  high  chimney  through  which  the  vapours 
may  be  discharged  is  here  greatly  increased.  The  rationale  of  this  is  that 
vapours  diffuse  so  rapidly  in  the  air  that  they  do  not  reach  the  ground  in  a 
sufficiently  condensed  form  to  prove  a  nuisance.  For  a  similar  reason  large 
airy  sheds  are  an  important  means  of  mitigating  nuisance,  not  only  by 
mechanically  restraining  the  escape  of  the  offensive  vapours,  but  also  by 
giving  them  time  to  be  well  diluted  with  air  before  they  are  discharged  into  the 
atmosphere.  The  passing  of  vapours  under  and  through  the  fire,  and  the  con- 
densing them  in  water,  will  also  be  found  available  means  of  abating  nuisance. 
A  cheap  and  effective  form  of  condensing  apparatus  may  be  made  by  means 
of  ordinary  drain-pipes,  containing  coke  in  lumps,  kept  cool  and  wet  by  water 
allowed  to  run  in  a  small  stream  through  it.  The  offensive  vapours  are 
conducted  into  this  condenser,  being  forced  by  a  fan,  &c.,  if  needful,  and  are 
found  at  the  outlet  to  be  almost  entirely  deprived  of  their  offensive  character. 

The  drying  of  the  bones  may  be  effectually  done  in  a  well-closed  chamber 
through  which  a  draught  is  maintained  into  the  chimney  ;  or  else  by  arti- 
ficial heat  created  by  charcoal  or  coke  fires  ;  or  by  a  short  sojourn  in  the 
boiler,  after  the  liquor  has  been  withdrawn,  the  heat  being  maintained  by 
the  steam  pipes.  Of  course  there  would  have  to  be  the  same  means  of 
carrying  off  and  dealing  with  the  vapour  from  the  bones  drying  in  the 
boiler  as  with  that  arising  from  them  while  they  were  being  boiled.  Almost 
any  method  is  preferable  to  the  '  bone-hole  '  whence  intolerable  stench  is 
liable  to  escape. 


OFFENSIVE  BUSINESSES  915 


FELLMONGEEING  AND   LEATHEB-MAKING 

The  preparation  of  skins  to  make  leather  is  important  from  a  sanitary 
point  of  view.  It  may  be  effected  so  as  to  be  harmless  and  inoffensive,  if 
great  care  be  exercised  ;  or,  on  the  other  hand,  it  may  be  carried  on  so  as  to 
be  a  great  and  offensive  nuisance,  causing  intolerable  stench  to  spread  to 
a  considerable  distance,  and  annoying  those  who  live  on  either  side,  according 
to  the  direction  of  the  prevailing  wind. 

Like  every  other  process  involving  the  treatment  of  more  or  less  offensive 
materials,  leather-making  has  found  champions  to  declare  it  a  panacea  for  all 
sorts  of  evils,  and  in  particular  it  has  been  described  as  a  preventive  as  well 
as  a  cure  for  phthisis  ! 

But  the  mere  fact  that  many  robust,  healthy  men  may  be  found  engaged 
in  the  trade  is  no  proof  whatever  that  it  is  healthy  ;  it  would  be  quite  suf- 
ficiently accoimted  for  by  the  fact  that  the  work  is  severe,  and  could  only  be 
■carried  on  by  robust,  healthy  workmen.  Again,  the  statistics  of  Beaugrand, 
who  found  among  171  cases  of  disease  occurring  among  ^  leather- workers ' 
28  of  pulmonary  phthisis,  are  worthless  as  a  general  statement.  The  figures 
are  too  small,  and  the  definition  of  the  work  too  vague,  to  be  of  the  least 
value. 

Tanning,  or  the  process  of  leather-making,  is  in  its  final  processes  a 
chemical  preparation  of  the  skin,  and  in  one  sense  may  be  regarded  as  a 
kind  of  dyeing,  when  we  consider  the  mode  in  which  the  tanning  agent 
penetrates  the  skin  and  attacks  its  individual  fibres.  The  power  to  precipitate 
solutions  of  albumen  and  glutei!  is  characteristic  of  substances  which  can 
convert  skins  into  leather.  The  conversion  into  leather  prevents  skins  from 
putrefying ;  and  altogether  the  process  must  be  regarded,  as  described  by 
Knapp,  as  being  one. in  which  the  fibres  do  not  cling  together  in  drying. 

Leather-making  consists  of  two  chief  stages  :  (1)  '  tanning  '  proper,  or 
the  conversion  of  the  raw  putrescible  hide  into  an  imputrescible  and  more 
or  less  flexible  material  known  as  leather,  and  (2)  '  currying,'  in  which  by 
treatment  with  fatty  and  other  matters  the  leather  is  rendered  more  soft, 
supple,  and  waterproof,  and  improved  in  appearance. 

Soft  materials,  such  as  glove  kid,  are  not  tanned,  but  '  tawed,'  in  which 
process  treatment  with  alum  and  salt  is  the  chief  means  employed.  Some- 
times skins  are  merely  treated  in  a  rough  way  by  inunction  with  fatty 
matter,  and  are  thus  rendered  less  liable  to  putrefaction,  though  they  usually 
retain  a  '  strong,'  unpleasant  smell. 

Enamelled,  patent,  or  japanned  leathers  are  finished  with  a  bright,  var- 
nished, waterproof  surface  on  one  side.  The  terms  patent  or  japanned  are 
generally  used  when  the  surface  is  smooth  and  bright,  while  '  enamelled  '  is 
the  term  used  when  the  surface  is  grained  or  roughened.  The  artificial  sur- 
face consists  of  coatings  of  a  sort  of  paint,  consisting  of  lampblack,  Prussian 
blue,  and  linseed  oil,  ground  together  and  applied  in  several  layers,  each  of 
which  is  dried  in  an  oven  at  about  160°-170''  F.  Each  coat  when  diy  is 
rubbed  smooth  with  pumice-stone ;  and  after  the  last  one  has  been  so 
treated  a  coat  of  oil  varnish  is  applied,  and  afterwards  dried  in  the  oven. 

Morocco  leather  is  properly  made  from  goat-skins.  After  being  unhaired 
in  the  usual  way  the  skins  are  bated  with  dog's  dung  and  water,  and  are 
tanned  chiefly  with  sumach.  The  grain  or  polish  is  given  by  working  under 
rollers  or  boards. 

Bussia  Leather. — The  skins  for  making  this  leather  are  bated,  after 
liming,  with  a  drench  of  rye,  oatmeal,  and  salt,  or  with  dogs'  dung  or  sour 

3n2 


916-  HYGIENE 

liquors.  They  are  again  treated,  after  tauning,  with  a  weak  liquor  of  vje 
and  oatmeal.  The  peculiar  odour  is  due  to  saturation  with  birch-oil.  The 
usual  dye  is  Brazil  wood.  The  markings  on  the  leather  are  produced  by 
rollers. 

Calf  Kid. — This  leather  is  '  tawed  '  hke  glove  kid,  and  not  tanned  like 
ordinary  leather. 

Glove  kid  is  chiefly  made  from  lamb  and  kid  skin,  skin  of  very  young 
animals  being  used  for  the  finest  kid. 

PrejMratioii  of  Hides  for  Tanning. — The  hides  are  received  some  fresh, 
and  some  salted,  all  more  or  less  filthy.  Both  kinds  are  first  well  soaked  in 
water,  the  salted  ones  for  a  longer  time  than  the  others. 

The  object  is  to  thoroughly  soften  and  cleanse  the  hide  without  it  being 
allowing  it  to  putrefy.  To  assist  this  process,  brine  is  sometimes  used  ;  or 
borax,  sulphide  of  sodium,  &c.,  is  added  to  the  wash.  Sometimes  putrid 
liquors  are  used,  especially  for  skins  known  as  Indian  '  kips.' 

Unliairing  the  Hide. — This  is  almost  universally  done  in  England  by  the 
aid  of  lime.  The  lime- wash  is  of  no  very  definite  strength,  but  there  is- 
always  a  considerable  quantity  of  lime  in  suspension.  The  hme-water  dis- 
solves the  substance  which  unites  the  fibres  of  the  skin  together,  and  it  also 
removes  the  albumen  present  in  the  hide  (in  the  blood-vessels,  connective 
tissue,  &c.)  The  epidermal  layer  of  the  skin  softens  and  swells  in  the  lime 
bath,  and  the  hairs  are  so  loosened  that  scraping  with  a  blunt  knife  causes 
the  whole  rete  Malpighi  and  hair  follicles  to  come  away.  At  the  same 
time  the  skin  becomes  swollen  and  plump,  which  renders  the  'fleshing' 
(i.e.  the  removal  of  adherent  particles  of  flesh)  easier ;  the  fat  of  the  hide  is 
also  converted  by  the  lime  into  an  insoluble  soap,  and  the  removal  of  the 
hair  is  made  easier. 

The  hming  is  usually  done  by  simply  plunging  the  skins  into  large  pits 
of  hme  and  water,  out  of  which  they  are  drawn  ('  hauled ')  once  or  twice 
daily,  while  the  undissolved  lime  is  stirred  up.  There  is  used  roughly 
from  one  to  four  poimds  of  hme  per  hide  in  the  pit.  Instead  of  being  simply 
left  lying  in  the  pit,  the  hides  are  sometimes  placed  on  frames,  which  can 
be  raised  and  lowered  at  wall  in  the  water.  An  addition  of  orpiment  is 
very  commonly  made  to  the  lime  to  facilitate  depilation.  In  America  and 
on  the  Continent  the  unliairing  is  frequently  done  by '  sweating,'  which  may 
be  'warm'  or '  cold,'  both  processes  being  essentially  dependent  on  partial 
putrefaction.  The  former  was  a  crude  method,  and  consisted  of  piling  the 
hides  and  inducing  slight  putrefaction  and  heat,  the  hides  if  necessary  being 
covered  wdth  fermenting  tan. 

The  '  cold  sweating,'  or  American  method,  consists  of  hanging  the  hides 
in  moist  '  sweating  pits  '  at  a  uniform  temperature  of  about  60°-70°  F. 

When  the  hair  has  been  thoroughly  loosened  by  one  of  these  methods 
it  is  scraped  off  by  a  large  two-handled  knife,  and  scraps  of  fat  and  flesh  are 
removed  from  the  inner  side  by  scraping,  brushing,  or  paring,  the  hide 
being  well  worked,  to  press  out,  as  far  as  possible,  any  fat  in  the  tissues. 

After  being  unhaired  and  fleshed,  the  hides  are  commonly  cut  up  into 
'bests,'  or  the  best  and  thickest  parts,  and  the  'offal,'  or  lighter  parts. 
These  have  next  to  be  thoroughly  freed  from  any  adherent  lime  before  being 
tanned.  This  is  done  by  placing  them  in  water  for  from  twelve  to  twenty- 
four  hours. 

Tanning  consists  in  treating  the  liides,  after  liming  and  washing,  with 
bark  or  some  substance  containing  tannin.  The  chief  substances  used  are 
oak-bark,  one  of  the  oldest  and  most  popular  substances,  divi-divi  (a  South 
American  bean,  Gisalpinacoriaria),  chestnut  extract  (prepared  from  rasped' 


OFFENSIVE  BUSINESSES  917 

■wood  of  the  Spanish  chestnut),  hemlock  extract  (from  bark  of  American  hem- 
lock pine),  valonia  (the  acorn  cup  of  an  evergreen  oak  grown  in  Greece  and 
the  Levant),  mimosa  bark  (from  several  kinds  of  Australian  acacias),  myra- 
bolans  or  myrobalans  (the  fruit  of  an  Indian  shrub),  catechu,  kino, 
sumach,  &o. 

The  ground  tan  is  placed  in  pits  made  of  flag-stone,  cement,  crick,  &c., 
the  pits  being  arranged  in  series  according  to  the  strength  of  the  liquor,  the 
skins  being  placed  first  in  the  weakest  one  and  afterwards  successively 
passed  through  each  of  the  whole  series. 

The  leather,  after  removal  from  the  tan-pit,  is  hung  on  drying  poles  in 
drying  lofts  till  half-dry,  and  is  then  placed  in  piles  on  the  floor  till  it 
*  sweats  '  or  '  heats  '  a  little.  It  is  subsequently  scraped,  oiled,  and  rolled  to 
improve  the  texture  and  surface,  and  is  often  coloured.  For  some  purposes 
hides  are  '  shaved  '  or  cut  down  in  thickness,  or  split. 

Currying  has  for  its  object  the  preparation  of  soft,  flexible  leather,  such, 
■e.g.,  as  is  used  for  the  uppers  of  boots,  for  flexible  belting  for  machinery,  &c. 
When  the  skins  have  been  removed  from  the  tan-pits  they  are  dried,  then 
scraped  and  levelled ;  subsequently  they  undergo  further  steeping,  heating, 
and  stretching,  and  are  again  dried.  After  this  they  are  oiled.  Various  kinds 
of  oil  are  used  for  oiling  in  the  grain — whale,  cod-liver,  castor,  linseed,  &c. — 
while  for  oiling  on  the  flesh  a  mixture  of  tallow  and  cUgras  is  considered  the 
best.  [Degras  is  the  surplus  oil  which  is  got  by  exudation  and  pressing  from 
the  oiled  chamois  leather  while  in  process  of  manufacture.] 

From  this  sketch  of  the  manufacture  of  leather  it  will  be  seen  that  it  calls 
for  the  supervision  of  the  Sanitary  Authority,  and  may  readily  prove  a  source 
of  serious  nuisance  in  thickly  populated  districts.  And  yet  leather-making 
may  with  proper  care  be  carried  on,  and  is  so  in  many  populous  places,  with- 
out complaint  or  apparent  harm  to  the  inhabitants. 

But  tanneries  might  with  advantage  be  relegated  to  suburban  and  open 
■districts  J  although  if  situated  far  from  the  sewers  of  the  town  nuisances  may 
arise  from  the  disposal  of  the  various  liquors,  which  are  often  offensive. 
Among  the  sanitary  precautions  called  for  is  in  the  first  place  the  prevention 
of  the  pollution  of  rivers  by  the  discharge  of  wash-water  or  spent  liquor. 
Precipitation  by  lime  and  clarification  should  be  insisted  on  in  all  cases  before 
such  waters  are  allowed  to  run  off.  Where  the  pits  are  within  dangerous 
proximity  to  a  stream,  it  is  advisable  to  have  an  escape  tank,  the  bottom  of 
which  is  well  below  the  level  of  the  river,  in  which  the  liquors  can  be  treated. 
Ultimately  even  filtration  through  sand  or  treatment  with  a  deodorant  may 
be  called  for. 

Nuisance  may  arise  also  from  solid  waste,  hair,  bits  of  flesh,  fat,  skin, 
&c.,  as  well  as  from  the  d6bris  from  the  bottom  of  the  lime  and  tan-pits. 
The  former  are  useful  for  glue-making  and  manure,  while  horns  are  used  for 
comb  and  knife-handle  making.  The  spent  tan  is  also  good  for  manure,  and 
the  liquor  may  with  advantage  in  many  cases  be  used  for  irrigating  land. 

The  possibihty  of  the  presence  of  arsenic,  especially  in  the  case  of  the 
skins  of  rarer  animals,  which  are  often  roughly  treated  with  it  immediately 
after  removal  fr'om  the  animal  in  order  to  preserve  them  during  carriage, 
jnust  be  borne  in  mind. 

Nuisance  is  especially  Hable  to  arise  from  bits  of  flesh,  &c.,  being  allowed 
to  accumulate  and  putrefy  on  the  premises  until  a  sufficient  quantity  has 
been  collected  to  make  a  load  for  removal ;  such  debris  should  be  fr-equently 
removed  and  should  be  kept  in  suitable  air-tight  receptacles.  This  source  of 
nuisance,  it  will  be  noted,  is  not  essential  to  the  trade,  but  arises  fr-om  culpable 
neglect. 


918  HYGIENE 

When  gas  lime  is  used  instead  of  fresh  lime,  serious  danger  may  arise- 
fi.'om  gases  evolved  through  the  action  of  acid  liquors  ;  sulphuretted  hydrogen 
and  carbon  dioxide  may  be  given  ofi'  in  fatal  quantities. 

The  dyeing  of  leather  has  sanitary  importance  from  the  fact  that  in  some 
cases  dangerous  metals  are  used  for  the  purpose.  For  instance,  an  alkaline- 
solution  of  oxide  of  lead  is  used  in  the  preparation  of  astrachan,  which  dyes 
the  hail'  black,  but  leaves  the  skin  white.  Such  skins  often  contain  much 
lead  dust,  which  is  frequently  left  in  the  hair  purposely  as  a  protection 
against  moths.  Again,  the  skins  of  foxes,  otters,  badgers,  and  rabbits,  are 
often  treated  with  a  mixture  containing  protosulphate  of  iron,  orpiment, 
oxide  of  lead;  common  salt,  acetate  of  copper,  and  other  ingredients  of  a, 
highly  poisonous  character. 

Wash-water  from  skins  which  have  been  treated  with  orpiment  and  lime 
readily  gives  off  sulphuretted  hydrogen,  which  leads  to  the  production  of 
sulphide  of  arsenic,  and  by  oxidation  to  formation  of  arsenious  and  sulphurous 
acids.  Free  arsenious  acid  may  also  be  discharged  from  the  orpiment  and 
form  combinations  with  some  of  the  calcium,  which,  however,  are  soon  re- 
dissolved  by  the  ammonia  present  whenever  there  is  putrefaction.  The 
danger  arising  from  the  presence  of  such  poisons  is  best  obviated  by  treat- 
ment with  salts  of  iron,  which  form  insoluble  arseniates. 

With  regard  to  the  etl'ects  of  leather-making  on  the  workmen  employed, 
there  does  not  seem  to  be  any  special  danger  or  trouble  to  which  they  are 
hable.  Some  suffer  from  local  excoriation  and  sores  in  the  hands,  and 
especially  the  fingers ;  which  is  no  doubt  mainly  due  to  the  action  of  the 
lime,  though  in  some  cases  the  arsenic  (orpiment)  used  is  more  particularly 
blamed.  Sometimes  this  ailment  takes  a  rather  characteristic  form,  occurring 
as  small  perforating  holes  in  the  pulp  of  the  fingers  from  which  blood  oozes, 
and  which  are  sometimes  difficult  to  heal. 

As  to  the  use  of  gloves  by  the  workmen  for  protection  against  the  action 
of  the  lime,  the  men  themselves  say  that  the  danger  from  Hme  getting  inside 
the  gloves  and  acting  on  the  hands,  without  chance  of  being  rubbed  off,  is 
much  greater  than  when  their  hands  are  quite  unprotected.  There  are  no  doubt 
some  grounds  for  this  objection;  still  there  seems  no  reason  why  gloves  to 
reach  well  up  the  arm  should  not  be  used.  Workmen  are  ever  ready  to  find 
reasons  against  any  change  in  their  modus  operandi. 

The  construction  of  the  premises  where  this  business  is  carried  on  often 
leaves  much  to  be  desired.  The  more  carefully  they  are  adapted  to  the  work, 
the  less  likelihood  is  there  of  a  nuisance  arising.  It  is  very  important  that 
the  pits  should  be  all  perfectly  water-tight,  that  the  surface  of  the  floors 
around  should  be  smooth,  Avater-tight,  properly  sloped,  and  provided  with 
Well-laid  gutters.  The  more  open  the  whole  of  the  premises  are  to  the 
Hght  and  air  the  better.  The  walls  should  be  of  hard  smooth  material, 
especially  the  lower  five  to  six  feet,  where  they  are  liable  to  be  splashed,  so 
that  they  may  not  absorb  dirt,  and  that  they  may  be  washed  as  often  as 
necessary.  Water  for  this  purpose,  with  hose,  should  be  at  hand,  as  well  as 
conveniences  for  the  workpeople  to  wash  themselves. 

The  writer  once  succeeded  in  terminating  much  acrimonious  feehng 
and  legal  proceedings  between  certain  persons,  neighbours  of  leather  works 
and  the  proprietors,  by  a  simple  and  inexpensive  plan.  The  works  were 
situated  in  the  worst  possible  place— the  cellars  and  the  ground  floor  of  a  large 
building  in  a  very  thickly  populated  district  of  a  town.  The  building  was  in 
the  centre  of  a  long  row  of  warehouses,  all  of  which  were  occupied  ;  and  com- 
plaints of  the  nuisance  from  the  tannery  had  been  long,  continuous,  and. 
well-founded.     The  preventive  measures  adopted  were  (1)  reflooring  of  the 


OFFENSIVE  BUSINESSES  919* 

tannery  with  best  concrete,  properly  sloped  and  guttered,  and  concreting  of  the 
lower  five  feet  of  the  walls  ;  (2)  removal  of  all  wood-work  from  the  pits  ;  stone, 
brick,  or  concrete  to  be  used  instead  ;  (3)  provision  of  air-tight  iron  boxes  for 
scraps,  and  their  frequent  removal ;  (4)  proper  supply  of  water  and  hose ; 
(5)  provision  of  proper  aeration  of  the  premises  by  artificial  means  ;  (6j  the 
provision  of  a  sheet-iron  flue,  with  large  trumpet-end  leading  from  the  cellars 
and  opening  above  the  roof,  provided  with  a  powerful  sun-gas-burner  to  ensure 
a  good  draught.  At  first  there  were  complaints  arising  from  the  escape  of 
effluvium  from  the  top  of  the  flue,  which,  contrary  to  the  agreement,  had 
been  made  to  terminate  at  the  roof.  The  addition  of  ten  feet  to  the  height 
of  the  flue  had  the  satisfactory  result  that  no  further  complaints  were  made. 
The  workmen  were  as  pleased  with  the  result  as  the  neighbours. 

PIG- KEEPING 

Although  the  Public  Health  Act,  1875,  Sec.  47,  states  that  pigs  must  not 
be  kept  in  towns  so  as  to  be  a  nuisance,  and  the  Public  Health  (London)  Act, 
1891,  Sec.  17,  prohibits  in  the  metropolis  pigs  being  kept  so  as  to  be  a 
nuisance,  or  within  forty  feet  of  a  street,  still  pigs  are  kept  in  towns,  and  even 
within  the  metropolitan  area,  so  as  to  be  abominable  nuisances.  Even  in 
the  country  districts  much  greater  care  ought  to  be  exercised  in  the  keeping- 
of  pigs,  as  to  site  and  drainage  of  the  styes,  the  cleanliness  of  the  animals,, 
drainage,  &c. 

Pig-keeping  becomes  a  nuisance  (1)  on  account  of  the  sour,  stinking  food 
on  which  they  are  too  commonly  fed,  and  (2)  in  consequence  of  the  atrocious 
smell  of  their  excreta,  greatly  increased  by  being  left  unremoved  for  long 
periods. 

Pigs  are  very  frequently  fed  on  sour  refuse  vegetable  matter,  blood,  offal, 
and  other  abominations,  not,  perhaps,  as  is  vulgarly  stated,  because  th& 
animal  thrives  best  and  is  healthiest  when  so  fed,  but  because  it  is  thus 
rendered  a  useful  scavenger ;  and  in  one  sense  the  pig  does  become  a  valuable 
member  of  the  community  by  turning  into  useful  food  nutritious  substances 
that  would  otherwise  be  wasted.  There  is  no  doubt,  however,  that  the 
feeding  of  pigs  with  garbage  tends  to  the  spread  of  parasitic,  and  possibly 
other  diseases,  and  it  is  hardly  credible  that  the  flesh  of  animals  fed  on  filtL 
is  of  the  same  quahty  as  that  of  animals  fed  on  wholesome  food. 

Pig-styes  should  be  situated  at  a  considerable  distance  from  dwelling- 
houses  ;  they  should  be  floored  with  asphalte,  concrete,  or  other  hard  and 
impervious  material.  Jointless  floors  are  best.  There  should  be  a  proper 
slope  of  the  floor  towards  a  channel  leading  to  a  grating,  having  bars  not 
more  than  three-eighths  of  an  inch  apart,  and  communicating  with  the  drain 
by  a  trapped  inlet.  The  wash  and  other  materials  evolving  effluvium  should 
be  kept  in  impervious  air-tight  vessels.  The  animals  should  be  regularly 
washed  and  kept  clean.  Attention  to  these  matters  will  reduce  the  nuisance 
to  a  minimum  ;  and  it  should  not  be  forgotten  that  the  pig  is  naturally  a  cleaa 
animal,  always  depositing  its  excreta  in  a  special  portion  of  the  stye,  and 
keeping  the  remainder  clean,  if  there  is  sufficient  room. 

AETIFICIAL   MANUEES  > 

This  subject  is  one  of  the  first  importance,  from  the  magnitude  of  the 
trade  and  the  sanitary  questions  involved.     The  trade  utiHses  an  enormous 

'  The  reader  desirous  of  learning  full  details  on  this  important  subject,  so  difficult 
to  become  acquainted  with,  is  referred  to  Dr.  Ballard's  encyclopaedic  article,  to  which, 
the  writer  is  largely  indebted. 


920  HYGIENE 

amount  of  material  which  would  otherwise  be  absolutely  useless,  and  would 
be  most  difficult  to  get  rid  of  at  all ;  and  at  the  same  time  produces  a  most 
valuable  result,  some  small  compensation  for  the  reckless  waste  of  the  nutri- 
tion of  the  land  which  is  carried  on  in  the  waste  of  the  sewage  and  excrement 
of  the  population.  These  manures  are  designated  as  '  bone  manure,'  '  blood 
manure,'  '  poudrette,'  '  superphosphate,'  &c. 

The  materials  used  are  of  various  kinds  and  include  : — 

(1)  What  may  be  grouped  as  nitrogenous  materials  :  the  dSbris  of 
knackers'  yards,  rotten  flesh,  fish,  blood,  intestines  ;  offal  from  tanneries, 
tripe  and  trotter  boilers',  glue  works,  scraps  of  skin,  hair,  '  scutch,'  shoddy, 
night-soil,  &c. 

(2)  Phosphatic  materials  :  bones,  boiled,  unboiled  and  calcined,  animal 
charcoal  and  materials  retained  in  it  when  used  as  a  filter — e.g.  sugar-scums, 
fossil  bones,  coprolites,  mineral  phosphates  from  South  Carolina,  Germany, 
and  Spain,  and  apatite,  bone  black,  bone  ash,  &c, 

(3)  Saline  materials — e.g.  sulphate  of  ammonia,  common  salt,  and  nitrate 
of  soda. 

(4)  Deodorants  and  dryers — e.g.  soot,  gj^psum,  ashes  from  coal  and  burnt 
tar,  &c. 

During  the  process  of  manufacture,  sulphuric  acid  or  hydrochloric  acid  is 
used.  The  former  acid  is  commonly  used  as  '  chamber  acid  '  (that  is,  acid 
taken  and  used  direct  from  the  leaden  chamber  where  it  is  made),  and  as  such 
almost  invariably  contains  arsenic  as  a  chief  impurity.  From  two  to  three 
pounds  of  arsenious  acid  per  ton  of  chamber  acid  is  no  uncommon  quantity. 

'  Superphosphate  '  proper  is  prepared  from  a  mixture  of  mineral  phosphate 
and  ground  bones,  treated  with  sulphuric  acid.  The  minerals  are  crushed, 
ground,  and  sifted  so  as  to  reduce  them  to  a  fine  powder,  and  are  then 
mixed  with  sulphuric  acid.  The  crushed  bones  are  added  subsequently. 
The  mixing  is  done  in  small  works  by  hand,  but  in  large  works,  where 
extensive  buildings  and  machinery  are  often  devoted  to  this  manufacture,  it 
is  invariably  done  by  machinery.  The  mechanical  mixer  consists  of  a  re- 
ceiving box  for  the  materials,  and  an  axis  or  paddle  with  projections  which 
revolves  and  stirs  up  the  manure  as  it  is  supplied.  The  acid,  usually 
'  chamber  '  acid,  is  run  in  from  a  cistern,  and  is  stirred  up  with  the  dry  material 
until  a  thick  paste-like  mass  is  produced,  the  consistence  of  which  depends 
on  the  proportion  of  sulphate  of  calcium  formed.  This  process  only 
lasts  ten  to  fifteen  minutes,  and  is  accompanied  by  strong  chemical 
action,  and  the  evolution  of  great  heat  and  a  considerable  quantity  of 
vapour.  When  bones  alone,  without  mineral  phosphates,  are  used, 
the  heat  developed  has  been  known  to  reach  as  high  as  240°  F.  The 
vapour,  besides  water,  contains  among  other  injurious  substances  fluorine 
(tetrafluoride  of  silicon),  arsenic  (chloride  and  arseniuretted  hydrogen), 
and  small  quantities  of  antimony.  The  heat  is  useful  in  drying  the 
manure,  and  thus  facilitating  its  reduction  to  powder.  In  large  works 
the  manure  is  usually  allowed  to  pass  direct  from  the  mixer  into  a  special 
chamber,  called  the  '  hot  den,'  where  it  remains  for  a  period  of  one  to  four 
days,  according  to  the  demand.  If  it  is  too  thin,  some  gypsum  is  generally 
added  as  a  drier. 

After  being  deHvered  into  the  '  hot  den '  the  manure  continues  to 
give  off  offensive  fumes,  until  its  temperature  has  fallen.  Hence  this  den 
must  be  made  air-tight,  and  the  openings  into  it  be  capable  of  being 
accurately  closed  when  it  is  in  use.  By  being  allowed  to  cool  in  the 
den,  moreover,  a  good  deal  of  the  vapour  is  retained,  which  is  spread 
around  if  the  manure  be  manipulated  in  the  open  while  still  hot  and  damp. 


OFFENSIVE  BUSINESSES  921 

But  even  after  two  to  three  days'  retention  in  the  '  den  '  the  temperature  of 
the  manure  is  still  high,  and  when  being  dug  out  it  may  give  off  large 
quantities  of  offensive  vapour.  Ultimately  the  manure  is  pulverised,  in  large 
works,  by  machinery,  and  filled  into  gunny  bags,  in  which  it  is  sold. 

The  whole  process  of  manufacture  of  '  superphosphate  '  is  more  or  less 
offensive  to  the  sense  of  smell.  The  presence  of  the  organic  materials  from 
which  the  manure  is  to  be  made,  of  finished  and  fuming  manure,  and  the 
very  premises  themselves,  which  are  permanently  employed  for  the  production 
of  the  manure  and  continuously  exposed  to  the  action  of  these  vapours,  all 
make  the  special  smell  an  all-pervading  influence.  Still,  in  well-managed 
works  it  would  not  be  justifiable,  as  a  rule,  to  say  that  the  effluvium  is  a 
serious  nuisance  to  the  average  man,  and  in  the  ordinary  sense. 

The  nuisance  is  often  complained  of  even  before  the  materials  reach  the 
works,  owing  to  the  stench  caused  during  their  conveyance  there.  This 
can  be  obviated  partly  by  their  being  brought  as  far  as  possible  in  a  fresh 
state,  and  without  waiting  for  their  accumulation  to  form  a  large  consignment 
(which  means  also  increased  time  given  for  putrefaction),  and  more  completely 
by  their  being  brought  in  proper  air-tight  receptacles.  The  night-soil  '  pails  ' 
in  various  towns  are  sufficiently  well  fitted  to  allow  of  their  being  conveyed 
full  and  in  large  numbers  through  the  streets  without  any  nuisance  being 
caused.  When  received  at  the  works  the  materials  should  be  properly  stored. 
Gypsum  thrown  on  the  bones  acts  as  a  good  deodorant,  and  charcoal,  ashes, 
and  dry  earth  are  also  beneficial.  There  should  be  proper  cesspools  or  other 
receptacles  for  the  reception  of  the  night-soil. 

The  highly  irritant  vapours  which  arise  in  the  mixing  and  are  discharged 
from  the  '  hot  den '  may  be  dealt  with  on  the  same  principles  as  already 
referred  to  in  treating  of  effluvia  from  other  sources,  i.e.  by  fire,  water,  or  air : 
combustion,  solution,  condensation,  and  dilution.  The  vapours  may  be  con- 
ducted by  a  flue  and  fan  into  the  furnace,  or  if  necessary  the  whole  den 
should  be  within  a  well-built  shed,  and  the  vapours  between  the  two  might 
be  dealt  with  in  this  way.  Condensation  can  be  very  efficiently  effected  by 
means  of  a  long  flue  in  which  the  vapours,  hydrofluosilicic  acid,  arsenic,  offen- 
sive organic  gaseous  compounds,  &c.,  may  be  condensed,  and  never  reach  the 
chimney  at  all,  so  as  to  be  discharged  into  the  air.  In  some  large  works 
no  less  than  440  feet  of  condensing  passages  have  to  be  traversed  before 
the  chimney  is  reached.  The  length  and  efficacy  of  this  can  be  greatly 
increased  by  the  insertion  of  faults  to  compel  the  vapours  to  traverse  a 
tortuous  course.  The  vapours  may  also  be  treated  more  cheaply,  but  not 
more  effectually,  by  the  cold-water  shower-bath  ('  scrubbers '),  all  non- 
absorbed  gases  being  drawn  into  the  boiler  fire. 

'  Poudrette  '  is  the  name  given  to  a  manure  in  the  form  of  a  dry  powder, 
of  a  brownish  colour,  prepared  from  night-soil  treated  with  sulphuric  acid. 
Sometimes  other  ingredients  are  added,  or  may  even  predominate,  for  the 
term  is  not  applied  to  a  specific  compound,  but  its  commonest  signification 
is  that  stated  above.  The  processes  used  vary  considerably.  In  the  form 
employed  at  the  Corporation  Works  of  Manchester,  Eochdale,  Warrington, 
and  other  *  pail '  towns,  the  contents  of  the  pails  are  thrown  into  a  steam- 
jacketed  boiler  provided  with  a  revolving  stirrer  to  prevent  incrustation,  and 
holding  some  400  gallons,  in  which  they  are  desiccated  in  from  four  to  sis 
hours.  The  desiccated  excrement  ('poudrette')  is  discharged  by  an  opening 
in  the  bottom  of  the  boiler.  The  steam  in  the  jacket  is  under  a  pressure 
of  about  four  atmospheres.  About  thirteen  pounds  of  sulphmic  acid  are 
added  to  every  hundredweight  of  excrement  for  the  purpose  of  fixing  the 
ammonia.     Fish-offal  (heads,  guts,  &c.)  ground  in  a  mortar  mill  and  other 


922  HYGIENE 

waste  are  sometimes  added,  and  thus  a  useful  way  is  found  of  getting  rid  of 
a  troublesome  and  offensive  material.  About  92  to  93  per  cent,  of  the  weight 
of  material  is  lost  dm-ing  the  desiccation. 

The  vapours  from  the  boiler  are  drawn  off,  and  in  some  cases  are  condensed 
in  a  cold  shower-bath — in  one  case  in  a  pipe  run  along  the  bottom  of  a  stream 
— and  it  is  certainly  possible  to  conduct  the  whole  process  without  the  least 
nuisance  either  inside  or  outside  the  works. 

In  another  process,  the  acid  is  added  to  the  excrement  in  the  pails,  which 
is  then  thrown  into  a  Milburn's  desiccator  (patent  July  30,  1872,  No.  22GG),. 
from  which  after  being  partially  dried  it  is  removed  to  a  hot  drying-floor,  and 
is  subsequently  broken  up  and  packed  for  sale. 

According  to  another  process,  to  a  charge  of  some  550  gallons  of  excrement 
eiglity  pounds  of  magnesian  limestone  are  added  and  the  whole  is  distilled. 
The  ammonia  is  conducted  into  a  saturator  containmg  brown  sulphuric  acid, 
and  is  there  fixed.  The  offensive  vapours,  after  serving  to  partly  raise  the 
temperature  of  the  excrement  before  it  is  thrown  into  the  boiler,  are  con- 
densed and  run  into  the  drains.  The  sulphate  of  ammonium  recovered  is  a 
valuable  item,  and  it  serves  to  reduce  the  working  expenses. 

The  importance,  in  obviating  the  nuisance  on  such  works,  of  a  high 
chimney  with  powerful  draught,  and  of  a  long  flue,  to  the  efficiency  of  which 
a  good  fire  will  greatly  contribute,  cannot  be  overestimated.  It  should 
further  be  a  general  rule  that  the  whole  of  the  operations  should  be  con- 
ducted within  a  large,  airy,  closed  building,  except  where  some  obvious 
impossibility  exists  to  this  being  done  ;  and  this  will  be  very  rare. 


STOEAGE  AND  TEEATMENT  OF  VAEIOUS  MATTEES  WHICH  MAY 
BECOME  A  NUISANCE 

In  large  towns  it  is  very  difficult  to  avoid  the  accumulation  of  various 
materials  which,  harmless  while  fresh,  may  become  most  offensive,  and  a 
source  of  danger  to  health,  when  stored  for  some  time. 

Sanitary  authorities  are  usually  very  unwilling  to  give  much  assistance 
in  the  removal  of  what  is  termed  '  trade  refuse,'  and  seem  to  imagine  that  a 
fine  stroke  has  been  made  when  they  refuse  to  assist  dealers  in  the  removal 
of  an  accumulation  of  stinking  fish-heads  and  guts,  or  of  rotten  ff'uit  and  vege- 
tables from  the  same  premises  from  which  they  are  bound  by  law  to  remove 
night-soil.  The  Sanitary  Authority  may  be  within  their  rights,  but  are 
they  benefiting  the  public  by  this  action  ?  Private  individuals  have  not  the 
means  of  getting  rid  of  offensive  matter  of  this  kind,  and  they  shirk  the 
difficulty  by  letting  the  nuisance  increase  ;  further,  it  is  more  than  question- 
able whether  they  should  be  allowed  at  their  free  will  to  pitch  it  into  the  first 
convenient  corner,  quarry  hole,  or  ditch.  It  was  for  such  reasons  that  the 
law  was  made  to  encourage  sanitary  authorities  to  remove  night-soil,  because 
they  can  do  it  better  than  private  individuals,  and  have,  or  should  have, 
means  of  disposing  of  it,  if  not  at  a  profit,  at  least  so  as  to  diminish  the  cost 
of  removal.  The  rapid  disposal  of  such  materials  is  for  the  pubHc  benefit,  and 
no  body  of  ratepayers  would  ever  object  to  the  Local  Authority  doing  the  work. 

Manure 

Among  the  offensive  things  stored  about  houses  is  manure,  chiefly  horse- 
manure.  For  some  inscrutable  reason  the  dung  of  animals  has  come  to  be 
regarded  by  the  public  as  almost  unobjectionable,  while  the  sight  of  a  few 
ounces  of  human  excrement  will  sometimes  cause  quite  an  uproar. 


OFFENSIVE  BUSINESSES  92» 

Horses  must  be  kept  in  towns,  but  the  accumulation  of  their  dung  is  not 
necessary,  and  is  objectionable.  When  such  manure  is  allowed  to  accumu- 
late to  a  large  quantity  its  removal  is  very  offensive,  and  the  stench  often 
most  pungent  and  far-reaching,  and  is  quite  capable  of  passing  through 
ordinary  brick  walls,  to  say  nothing  of  doors,  windows,  and  chimneys. 

Dung-heaps  should  not  be  tolerated  in  the  populous  parts  of  towns,  and 
more  particularly  in  the  very  poor  parts.  Eemoval  every  two  to  three  days 
should  be  insisted  on,  and,  like  night-soil,  it  should  be  removed  at  night ;  the 
place  where  it  lies  in  the  yard  should  be  sheltered  from  the  rain,  and  should 
not  abut  on  the  wall  of  any  dwelling-house. 

The  custom  of  making  grooms,  stablemen,  &c.,  sleep  in  rooms  over  the 
stables  is  certainly  objectionable — not  entirely  because  the  companionship 
of  a  horse  is  injurious  to  a  man,  but  mainly  because  stables  are  generally 
situated  in  places  not  fit  for  men  to  live  in,  and  especially  so  in  large  towns, 
where  land  is  very  dear.  In  London  the  so-called  '  mews  '  are  hotbeds  of 
disease,  owing  to  the  foul  air  and  the  generally  uninhabitable  condition  of 
the  places  from  accumulation  of  manure  and  dirt. 

Bones 

Bones  soon  become  offensive  if  kept.  The  grease  attached  to  them  becomes 
decomposed,  capric,  caprylic  acids,  and  butyric,  and  other  products  of  putrefac- 
tion being  formed,  and  these  give  off  very  disgusting  smells.  They  are  often 
stored  in  private  houses  until  quite  putrid,  and  then  the  '  rag-man '  usually 
gets  them,  and  conveys  them  perhaps  to  his  own  home,  where  they  may  lie 
for  months,  before  he  finally  disposes  of  them  to  the  bone  boiler  or  manure 
maker. 

The  best  mode  of  preventing  this  nuisance  is  the  absolute  prohibition  of 
keeping  bones  in  quantity  in  any  house ;  rag-pickers  should  be  obliged  to 
dispose  of  them  at  once,  without  storing  them  for  any  time  in  their  homes. 
In  private  houses  they  should  be  burned,  like  all  garbage,  or  be  kept  as  far  from 
the  dwelling-house  as  possible  and  in  some  well-covered  receptacle,  but,  no 
matter  how  kept,  it  is  difficult  to  keep  down  a  stench,  if  kept  any  time. 

The  health  may  undoubtedly  suffer  from  the  effects  of  exposure  to  this 
nuisance. 

Fish 

While  the  smell  of  fresh  fish  is  pleasant,  that  of  stale  fish  is  horrible. 
'  Fresh  '  is  a  relative  term,  and  really  fresh  fish — that  is,  fish  not  more  than  a 
day  or  two  after  being  caught — is  unknown  in  most  of  our  large  towns.  The 
great  bulk  of  the  fish  in  England  is  not  landed  until  it  has  been  a  week  or 
even  longer  out  of  the  sea.  The  fishing-boats  from  Grimsby  and  other  great 
fishing  ports  go  to  sea  and  as  a  rule  do  not  return  for  some  seven  to  ten  days. 
The  fish  are  usually  kept  in  ice  during  this  time,  but  are  sometimes  kept  aUve 
in  tanks.  The  herring  fleets  are  escorted  by  special  boats,  which  convey  these 
delicate  fish  to  land  at  shorter  intervals. 

Hence  it  is  not  surprising  that  the  fish  which  the  salesman  declares  has 
*  only  arrived  to-day  '  may  go  bad  the  next  day. 

The  smell  of  bad  fish  is  most  adhesive,  and  the  nuisance  is  increased  by 
the  detachment  from  the  fish  of  the  scales  and  slime,  which  stick  to  every- 
thing and  putrefy.  Extreme  cleanliness  and  the  rapid  removal  of  all  garbage 
is  the  essential  condition  of  prevention  of  nuisance  from  fish. 

The  difficulty  is  increased  by  the  large  amount  of  d&bris,  guts,  skins, 
heads,  tails,  &c.,  which  are  necessarily  produced  in  the  way  of  business.    There 


924  HYGIENE 

is  seldom  adequate  provision  made  for  the  disposal  of  these  things ;  they  are 
allowed  to  accumulate  and  rot,  and  they  spoil  the  good  fish.  The  Sanitary 
Authority  should  be  ready  and  willing  to  assist  in  getting  fish-dealers  out  of 
their  difliculties  by  removing  all  their  refuse. 

Fish  refuse  may  be  advantageously  disposed  of  without  nuisance  by 
grinding  it  in  a  mortar  mill,  mixed  with  Ume  and  soot  or  ashes,  for  manure. 
Vegetable  refuse  may  be  also  ground  with  it. 

Like  other  filth,  decaying  fish  may  be  injurious  to  health. 

Feuit  and  Vegetables 

Fruit  and  vegetables  are  liable,  especially  in  summer  and  damp  weather, 
to  decay,  and  then  become  ofl'ensive.  The  immediate  removal  and  destructio]i 
of  decayed  fruit  is  the  only  step  to  be  taken,  except  the  preliminary  applica- 
tion of  deodorants. 

Vegetables  require  to  be  stored  in  cool,  well- ventilated  cellars,  where 
they  should  be  examined  fi-om  time  to  time  and  the  decaying  ones  removed. 

The  health  may  be  injuriously  affected  by  the  emanations  from  decaying 
fruit  and  vegetables. 

The  condemned  material  may  be  utilised  as  manure,  and  for  this  purpose 
should  be  conveyed  to  and  kept  at  a  suitable  distance  from  the  outskirts  of  the 
town.  A  considerable  quantity  of  it  may  also  be  more  expeditiously  utihsed 
by  grinding  it  in  a  mortar  mill  with  fish  debris  (q.v.).  Attempts  have  been 
made  to  get  rid  of  the  great  mass  of  vegetable  waste  that  accumulates  in 
towns  by  calcining  it  in  a  special  form  of  kiln,  and  the  results  have  been 
satisfactory,  except  from  a  pecuniary  point  of  view. 

Eggs 

On  the  premises  of  large  dealers  in  eggs,  who  dispose  of  vast  numbers 
weekly  in  the  ordinary  way  of  business,  there  is  always  a  considerable  number 
of  rotten  eggs,  which  are  very  offensive.  Careful  keeping  in  a  cool  cellar, 
with  supervision,  and  the  early  removal  of  bad  material,  wdth  the  use  of 
chlorinated  lime,  are  the  means  to  be  adopted  to  avoid  further  evils. 

Eags 

The  rag-picker  is  the  symbol  of  the  lowest  stage  of  civilised  life,  except 
the  pauper.  His  business  is  to  fill  his  bag  with  refuse  of  every  kind,  rags, 
bones,  scraps  of  meat,  old  clothes,  &c.,  which  he  does  regardless  of  quaUty, 
and  to  sell  them.  The  bones  he  sells  to  the  bone-boiler,  the  rags  he  collects 
for  sale  to  the  paper-maker  ;  however,  he  rarely  does  this  directly,  but  through 
a  middle  man.  The  latter  often  carries  on  business  in  an  extensive  way, 
exporting  the  material  to  distant  countries  :  he  stores  and  roughly  sorts 
immense  quantities  of  rags  in  premises  which  commonly  are  as  dilapidated 
as  the  '  raw  material '  of  his  trade.  The  rags,  collected  from  the  gutters, 
ash-pits,  and  any  other  place  where  they  are  found,  often  give  these  stores 
an  abominable  smell.  It  is  surprising  that  infectious  disease  is  not  frequently 
traceable  to  these  places,  as  the  quality  of  the  rags  is  never  questioned,  and 
they  must  often  come  from  infected  premises.  Small-pox  and  woolsorters' 
anthrax  have  been  traced  to  infection  from  rags. 

That  all  such  places  should  be  under  the  watchful  care  of  the  Sanitary 
Authority  is  obvious.  The  stores  and  contents  should  certainly  be  disinfected 
from  time  to  time,  and  the  use  of  lime-wash  should  be  insisted  on.     Every 


OFFENSIVE  BUSINESSES  925' 

effort  should  also  be  made  to  prevent  infected  articles — bedding,  old  clothes, 
&c. — being  deposited  in  such  places  until  they  have  been  rendered  harmless 
by  disinfection. 

CAKPET-CLEANING 

The  knowledge  that  infectious  virus  is  a  tangible  thing,  emanating  from 
the  infected  person,  and  that  it  may  be  found  deposited  on  carpets  and  other 
articles  of  furniture,  makes  it  obviously  improper  that  carpets  should  con- 
tinue in  the  old-fashioned  way  to  be  shaken  and  beaten  in  the  streets  and 
yards,  or  sha,ken  out  of  the  windows.  Apart  from  the  danger  of  infection, 
there  is  the  nuisance  from  the  dust.  In  most  towns  of  any  size  there  are 
now  carpet-cleaning  establishments.  These  places  are  sometimes  a  source 
of  annoyance  from  the  noise  of  the  machinery,  as  well  as  from  the  dust, 
which  is  in  some  places  allowed  to  escape  from  windows  but  little  elevated 
above  the  street.  This  should  never  be  permitted.  The  dust  should  either 
be  drawn  by  a  fan,  &c.,  into  a  high  chimney,  whence  it  will  be  rapidly  blown 
about  through  the  air,  or,  what  is  much  better,  be  drawn  under  and  into  the 
boiler-fire,  where  it  will  be  destroyed. 

HAIR-   AND   FLOCK-PICKING 

Unfortunately  it  is  not  the  general  custom  to  have  beds,  pillows,  feather 
quilts,  and  such  articles  opened  up  and  cleaned  from  time  to  time.  Such 
things  are  often  used  for  generations  in  a  family  without  ever  being  taken  to 
pieces,  repicked  and  cleaned,  and  not  infrequently  are  sold  and  bought  and 
treated  in  the  same  way.  And  yet  a  moment's  consideration  will  convince  that 
they  must  become  laden  with  dirt,  if  not  with  infectious  matter.  Observation 
of  the  process  of  picking  an  old  mattress  would  astonish  most  people  by  the 
clouds  of  dust  (=  dry  filth)  with  which  it  is  laden.  There  is  no  doubt  that 
pathogenic  organisms  remain  quiescent  in  such  receptacles,  and  become  active 
and  dangerous  when  favourable  conditions  arrive  ;  this  has  been  proved  by 
experiment. 

This  work  is  usually  done  by  hand  in  the  houses  of  poor  persons.  It  is 
greatly  to  be  desired  that  it  should  become  a  regular  practice  to  have  all  such 
articles  cleaned  from  time  to  time,  and  that  suitable  establishments,  where 
the  work  would  be  done  by  machinery,  should  be  erected  in  aU  towns. 

STEEET   SWEEPING 

The  maintenance  of  the  streets  in  a  clean  state,  free  from  dirt  and  dust, 
is  one  of  the  most  important  pubHc  sanitary  arrangements,  second  only  to 
drainage  and  sewerage,  although  it  is  very  unusually  looked  on  as  of  such 
value.  That  the  surface  of  the  streets  should  be  hard,  smooth,  and  imper- 
vious is  of  the  utmost  importance,  not  only  for  the  convenience  of  traffic,  but 
for  the  prevention  of  the  accumulation  of  filth,  which  too  often  is  the  parent 
of  disease,  as  well  as  of  discomfort. 

It  must  be  remembered  that  the  area  of  the  streets  is  considerable  ;  that 
they  are  continually  befouled  with  excrement  of  healthy  and  diseased 
animals,  and  not  infrequently  of  hmnan  beings,  and  receive  offal  of  every 
kind  from  the  houses  ;  in  the  poorer  parts  people  commonly  throw  their 
slops,  sweepings,  and  every  kind  of  rubbish  into  the  street.  The  streets  are 
subject  to  those  changes  of  dryness  and  moisture  which  are  most  favourable 
to  putrefaction ;   they  are  continuously  traversed  by  the  people,  and   are 


«26  HYGIENE 

the  playgrounds  for  the  cliildren  of  the  poor,  and  often  are  the  only  place 
where  the  adult  poor  can  rest  in  the  open  ah'  after  work  is  over.  All  day 
long  the  door  of  the  poor  man's  dwelling-room  opens  direct  on  to  the  street 
(usuaUy  this  room  is  too  dark  and  close  to  be  habitable  if  the  door  were 
kept  shut),  and  all  day  his  family  live  almost  in  direct  contact  with  the 
street  and  its  emanations. 

Ordinary  mud  is  practically  not  very  different  from  sewage,  yet  we  com- 
monly tolerate  during  many  months  of  the  year  acres  of  streets  covered  with 
mud,  more  or  less  solid,  evaporating  its  moisture  and  sending  its  stenches 
into  our  lungs  and  houses.  When  dry  weather  ensues  the  dry  mud  is  con- 
verted into  dust,  and  penetrates  bodily  into  our  mouths  (to  be  swallowed) 
and  noses  (on  its  way  to  the  lungs)  and  spreads  itself  over  every  part  of  our 
houses,  where  it  deposits  itself  on  our  food,  furniture,  walls,  &c. 

The  direct  connection  of  disease  with  the  existence  of  acres  of  evapo- 
rating slush  in  our  streets,  or  with  clouds  of  dust,  has  never  been  esta- 
blished. But  a  moment's  thought  will  convince  that  it  is  more  difficult  to 
conceive  these  conditions  as  being  harmless,  than  to  realise  that  they  can 
continue  with  impunity. 

Hence  the  importance  of  the  work  of  the  street-sweeper.  His  work, 
being  usually  regarded  as  of  very  secondary  importance,  and  as  being  mainly 
required  to  prevent  mechanical  obstruction  from  mud,  or  to  check  the  com- 
plaints of  the  public  as  to  dust,  is  seldom  properly  done.  The  usual  way  of 
remo\Tng  dust  is  to  try  to  sweep  it  into  small  heaps  while  perfectly  dry,  and 
possibly  while  a  brisk  wind  is  blowing,  and  to  put  into  an  open  cart  so  much 
of  the  heap  as  the  wind  does  not  blow  away,  and  to  remove  as  much  of 
the  cartload  as  the  wind  leaves  in  it  to  the  tip,  or  depot  for  mud  and 
manure,  if  one  exist  in  the  town.  This  is  the  ordinary  mode  of  procedure, 
and  it  is  calculated  to  aggravate  rather  than  lessen  the  evil.  It  encourages 
the  blowing  about  of  the  dust,  and  the  sweeper  is  only  an  unnecessary  ex- 
pense.    The  dust  should  always  be  damped  before  the  sweeping  is  done. 

But  the  difficulty  with  the  dust  would  be  greatly  lessened  if  the  mud, 
which  is  so  easy  to  remove,  were  not  allowed  to  accumulate  to  form  dust. 
The  removal  of  mud  is  a  mere  mechanical  labour,  much  easier  than  the 
removal  of  the  dust. 

During  ram  the  sweeper  should  be  at  work  assisting  the  rain  to  clean  the 
streets.  But  the  mud  should  be  carted  away  at  once,  and  not  left  lying  in 
heaps  on  the  roadside  until  it  has  been  spread  over  the  surface  again  by  the 
traffic,  as  is  very  commonly  the  case,  or  until  it  has  been  converted  into  dust 
during  the  next  dry  weather.  The  mechanical  sweepers  drawn  along  by  a 
horse  are  excellent  for  this  work. 

The  suggestion  to  use  for  allaying  the  dust  a  solution  of  chloride  of 
calcium,  a  very  deliquescent  salt,  which  retains  much  moisture,  might  in 
exceptional  circumstances  be  useful. 

But  it  should  never  be  permitted  to  dissolve  ice  and  snow  on  the  streets 
by  admixture  of  salt,  because  it  forms  an  intensely  cold  '  freezing  mixture,' 
injurious  to  boots  and  cruel  to  the  wearer.  The  reality  of  this  may  be 
judged  from  the  fact  that  such  a  mixture  will  give  a  reduction  of  tempera- 
ture of  from  +  10°  to  -  18°  C.  (1°  C.=  1-8°  F.) 

OIL-CLOTH   (FLOOE-CLOTH),  LINOLEUM 

The  term  '  floor-cloth '  was  originally  applied  to  a  cloth  covered  with 
several  layers  of  paint.     But  owmg  to  certain  defects — its  coldness,  shpperi- 


OFFENSIVE  BUSINESSES  927 

3iess  and  hardness — this  substance  is  being  superseded  by  kamptuhcon, 
hnoleum,  and  other  substitutes,  free  from  these  defects,  and  quite  as 
cleanly. 

'  Oil-cloth '  is  made  of  coarse  canvas,  usually  manufactured  from  jute. 
It  is  suspended  on  a  frame,  which  can  be  extended  by  screws  so  as  to  stretch 
the  canvas,  and  on  this  it  is  coated  first  with  size  (to  smooth  the  surface  and 
also  prevent  the  corroding  action  of  the  oxidisation  of  the  linseed  oil  subse- 
quently applied) ;  afterwards  a  coating  of  very  thick  paint  (commonly  yellow 
>ochre  or  red  oxide  of  iron)  is  laid  on  with  a  trowel,  and  well  worked  in. 
Both  sides  are  treated  in  this  way,  and  when  this  layer  is  dry  additional 
ones  are  similarly  applied  ;  last  of  all  the  pattern  is  printed  on  after  the  oil- 
cloth has  been  taken  down  from  the  frame.  Blood  and  lime  are  sometimes 
used  instead  of  size. 

The  drying  is  a  tedious  process,  which  used  to  take  ten  to  twelve  months, 
but  it  is  now  effected  in  rooms  artificially  huated  to  about  180'^  F,  in  one- 
fourth  of  that  time.  During  the  drying  by  heat  very  offensive  vapours  are 
given  off. 

Linoleum  consists  mostly  of  cork,  finely  powdered  by  machinery,  linseed 
oil  oxidised  by  exposure  in  a  thin  film  to  the  air,  and  mixed  into  a  sort  of 
cement  with  rosin  and  Kauri  gum.  These  ingredients  are  heated  together 
in  a  steam -jacketed  pot,  provided  with  stirrers  and  an  air-tight  lid,  a  pipe 
from  which  conducts  the  vapours  into  the  furnace.  After  a  couple  of  hours 
the  fusion  is  complete,  and  the  '  cement '  is  discharged  into  a  cold  rolling- 
mill  beneath,  the  roller  being  hollow,  and  kept  cool  in  summer  by  cold 
water  inside.  The  fumes  given  off  at  this  stage  are  very  pungent  and 
offensive.  After  being  rolled,  the  cement  is  ready  for  use,  about  46  lb.  being 
mixed  with  56  lb.  of  the  ground  cork.  They  are  mixed  in  a  mill,  with  steam- 
heated  rollers,  the  colouring  matter  being  added,  yellow  ochre  and  barytes 
for  brown,  oxide  of  iron  and  vegetable  black  for  red.  Subsequently,  after 
■undergoing  further  processes  of  mixing,  the  compound  is  rolled  out  in  sheets, 
and  ultimately  applied  to  the  canvas  made  of  jute,  one  surface  only  being 
covered,  the  other  surface  bemg  protected  by  a  layer  of  '  backing,'  consisting 
of  size  and  pigment,  or  of  varnish.  If  necessary  the  surface  is  afterwards 
printed. 

There  is  considerable  danger  of  explosion  at  two  stages  of  this  manufacture  : 
(1)  during  the  pulverising  of  the  cork,  (2)  when  the  '  cement '  and  cork  are 
being  mixed.  The  fine  dust  floating  in  the  air  is  liable  to  ignite,  and  the 
cement  may  take  fire  spontaneously. 

The  character  of  the  nuisance  from  both  these  manufactures  is  similar, 
almost  identical,  and  arises  from  the  vapour  given  off  by  the  hot  oil.  In 
the  hot  drying-rooms  for  '  oil-cloth  '  it  is  hardly  possible  to  breathe  after  the 
cloths  have  been  drying  for  some  hours.  The  vapours  cause  a  great  nuisance 
even  at  a  considerable  distance  from  the  works.  The  only  satisfactory  way 
of  treating  them  is  to  propel  them  by. a  fan  into  the  furnace  and  burn  them, 
the  process  being  greatly  assisted  by  preliminary  passing  through  water. 

MANUFACTURE   OF   VAENISH 

A  varnish  is  a  substance  which  apphed  to  the  surface  of  an  object 
increases  its  lustre,  preserves  it  from  damp  and  weather,  provides  a  hard 
smooth  coating,  and  improves  the  appearance. 

There  are  various  kinds  of  varnish :  e.g.  '  drying  oils,'  which  become 
hard  and  resinous  by  oxidation  in  the  air  ;  oil  varnishes,  consisting  of  a  resin 
and  drying  oil ;  compounds  of  gums,  resins,  &c.,  in  a  volatile  liquid,  which 


928  IIYGIEXE 

by  evaporation  leave  the  precipitated  solids  as  a  glassy  coating.  '  Driers ' 
are  substances  which  accelerate  the  drying  of  oils,  by  themselves  giving  up 
oxygen,  or  by  acting  as  carriers  of  atmospheric  oxygen  ;  oxide  of  manganese 
and  oxide  of  lead  are  among  the  substances  commonly  used  for  this  purpose. 

The  principal  resins  used  to  make  varnish  are  true  copals,  animi,  dam- 
mar, kauri,  &c. 

The  following  is  the  usual  process  of  manufacture.  The  resin  is  melted 
in  a  deep,  narrow  pot  either  by  a  coal  fire  or  gas,  and  when  fusion  is  complete 
the  action  of  the  heat  is  discontinued  (either  by  removing  the  fire  or  the  pot), 
and  the  oil  (linseed  oil  commonly),  which  has  simultaneously  been  heated 
to  about  G00°  F.,  is  poured  on  the  melted  resin  and  stirred.  The  liquid  is  now 
boiled  in  a  shallow  open  pot,  it  being  desirable  at  this  stage  to  expose  it  freely 
to  the  air,  contrary  to  what  is  needed  during  the  melting  of  the  resin.  If 
necessary  the  mixture  is  thinned  Avith  turpentine  when  cool.  Sometimes 
the  resin  after  being  melted  is  cooled  and  subsequently  dissolved  in  the  oil  by 
heat,  or  the  raw  resin  is  fused  in  the  oil. 

The  vapours  given  off  during  the  manufacture  are  generally  very  offen- 
sive and  far-reaching,  and  are  complained  of  as  causing  headache,  malaise, 
&c.,  by  those  exposed  to  them  even  at  some  distance. 

The  annoyance  is  due  partly  to  the  vapour  from  the  boiling  oil  (acro- 
lein), partly  to  those  from  the  melting  resins.  The  most  effective  preven- 
tive is  the  condensation,  either  through  a  '  continuous  condenser  '  (similar 
to  that  used  for  condensing  the  impurities  in  coal-gas)  or  in  water  ;  or 
combustion  in  a  fire  may  be  resorted  to  ;  this,  however,  is  an  extravagant 
method,  as  the  condensed  vapours  yield  products  useful  in  the  manufacture 
of  Brunswick  black. 

THE   BOILING   OP   OIL 

All  oils  have  not  the  same  properties  as  '  drying  oils  ; '  some,  on  exposure 
to  air,  absorb  oxygen,  lose  their  greasiness,  and  become  dry  and  hard  more 
readily  and  completely  than  others  ;  and  it  is  the  possession  of  these  qualities 
which  constitutes  a  '  drying  oil.'  This  valuable  property  of  oxidising  and 
drying  is  increased  by  ( 1)  exposure  to  the  air  m  a  thin  film  ;  (2  i  heating,  or  as 
it  is  improperly  termed,  '  boiling ; '  (3)  the  addition  of  '  driers '  (substances 
which  accelerate  the  desiccation  by  parting  with  some  of  their  own  oxygen, 
or  acting  as  carriers  of  atmospheric  oxygen),  the  chief  of  which  are  sulphate 
of  zinc,  peroxide  of  iron  (umber),  and  protoxide  of  lead  (litharge).  The  first 
acts  by  assisting  the  separation  of  the  vegetable  albumen  and  substances 
which  hinder  the  drying,  while  the  other  two  are  oxidisers. 

Linseed  oil,  being  one  of  the  most  important  commercial  *  drying  oils,'  is 
the  one  specially  referred  to  in  the  following  observations. 

In  the  ordinary  process  it  is  boiled  in  an  open  iron  vessel,  heated  by  a 
fire,  sometimes  in  the  open,  sometimes  under  cover.  Such  pungent  vapours 
are  given  off  that  the  workmen  are  seriously  incommoded  if  they  are  freely 
exposed  to  them.  At  a  certain  stage  it  is  advantageous  to  subject  the  oil  to 
a  draught  of  air,  as  it  hastens  the  result.  A  still  more  effectual  method  is 
to  blow  air  through  the  mass  of  the  hot  oil.  The  open  fire  may  with  great 
advantage  be  replaced  by  steam  applied  by  means  of  a  jacketed  pan. 

The  vapours  given  off  are  very  pungent  and  irritating,  affecting  the  eyes 
and  causing  nausea,  headache,  malaise,  and  vomiting,  even  at  a  considerable 
distance  from  the  works. 

The  most  effective  method  of  preventing  nuisance  is  to  have  the  pot 
covered  with  a  hood,  from  which  a  pipe,  provided  with  a  fan,  drives  the 


OFFENSIVE  BUSINESSES  929 

vapour  into  a  fire,  either  that  of  the  boiler,  or  the  one  under  the  oil-pot  itself. 
The  nuisance  is  so  great  that,  if  necessary,  a  special  hot  coke  fire,  connected 
with  a  high  chimney,  should  be  provided  to  destroy  the  vapour.  It  is  usual 
to  ignite  oil  which  is  intended  for  making  printer's  ink,  whereby  the  nuisance 
of  smoke  is  superadded  to  irritating  stench.  This,  too,  should  be  done  under 
a  proper  hood  connected  with  a  ventilating  pipe  leading  to  the  chimney. 

PAPER-MAKING 

Paper  is  composed  chiefly  of  cellulose,  more  or  less  purified.  From  the 
thirteenth  century,  when  rags  were  first  used  for  paper-making,  up  till  1856, 
when  esparto  grass  was  introduced,  cotton  and  linen  rags  were  almost  exclu- 
sively used  for  paper-making.  Hemp,  old  ropes,  straw,  wood  made  into 
pulp,  canes,  bamboo,  waste  paper,  and  many  other  substances  are  now  used 
for  the  same  purpose. 

The  collecting  and  storing  of  rags,  considering  the  character  of  the  places 
they  come  from — infected  houses,  filthy  hovels,  &c. — even  if  mainly  done  for 
the  purpose  of  paper-making,  requires  mention  here  as  an  important  sani- 
tary question.  Care  must  be  taken  to  keep  them  dry,  as  they  may  heat  and 
ignite  spontaneously  through  slow  combustion. 

The  preparation  of  rags  for  paper  begins  with  dusting  them  in  a 
'  thrasher,'  a  machine  in  principle  similar  to  the  '  willowing  machine.'  After 
this  they  are  sorted  and  cut,  usually  by  hand,  into  pieces  about  two  to  five 
inches  square,  and  they  are  again  dusted  in  an  agitator,  after  which  they  are 
boiled,  usually  with  carbonate  of  soda  or  caustic  soda,  or  a  mixture  of  both. 

Next  they  are  bleached,  either  by  chlorine,  which  is  passed  into  a  closed 
brick  chamber,  in  which  the  rags  are  placed,  or  by  the  alternate  application  of 
bleaching  liquid  and  acid. 

The  subsequent  treatment  does  not  differ  essentially  from  that  of  esparto 
grass,  the  preliminary  treatment  of  which  will  next  be  described.  After  a 
preliminary  picking  out  of  impurities,  the  grass  is  boiled  with  caustic  alkali 
in  a  boiler  with  a  perforated  false  bottom,  steam  entering  beneath  the  false 
bottom  and  forcing  or  '  vomiting '  the  water  up  a  wide  tube,  so  that  it  is 
kept  in  constant  circulation.  This  boiler  is  necessarily  kept  closed  fast  by 
screwing  down  the  door. 

After  a  time  the  liquor,  which  is  very  foul  and  contains  resin,  siHca,  &e., 
extracted  from  the  grass,  is  runoff  into  a  store  well,  and  fresh  water  is  poured 
on  and  the  boiling  is  repeated,  after  which  the  grass  is  reduced  to  pulp  by 
machinery.  The  manufacture  of  paper  from  the  pulp  does  not  require  men- 
tion here. 

The  recovery  of  the  soda  from  the  wash  liquor  is  an  important  economical 
operation,  and  is  one  of  the  most  offensive  parts  of  the  whole  manufacture. 
The  process  employed  consists  practically  in  the  evaporation  of  the  liquid, 
and  subsequent  incineration  of  the  residue,  during  which  carbonic  acid  is 
formed  from  the  vegetable  matter,  and  combines  with  the  soda  to  form  car- 
bonate of  sodium.     This  when  treated  with  lime  forms  caustic  soda. 

The  vapours  given  off  during  the  boiling  of  the  grass,  and  from  the  hot 
liquor  and  grass  after  removal  from  the  boilers,  cause  an  unpleasant  odour 
which  has  been  compared  to  senna,  and  sometimes  complained  of  as  a 
nuisance  by  neighbours.  This  can  be  entirely  prevented  by  condensation  in 
cold  water,  the  hot  liquor  being  run  in  a  coil  of  pipe  through  the  water.  Cold 
water  applied  at  once  to  the  grass,  after  it  is  boiled,  will  entirely  prevent  the 
unnecessary  annoyance  from  vapours  given  off  from  it  while  cooling.     The 

VOL.  I.  3  o 


930  HYGIENE 

hot  liquor  should  be  run  into  a  cooling  tank,  there  to  remain  well  covered  in 
until  quite  cold. 

But  the  recovery  of  the  soda  leads  to  a  greater  nuisance,  partly  from  the 
vapour  given  oft'  during  evaporation,  still  more  from  the  pungent  empy- 
reuniatic  fumes  produced  by  the  ignition  of  the  mass.  The  vapour  should 
be  conducted  by  a  flue  into  a  tall  chimney.  The  fumes  produced  during  in- 
cineration should  be  conducted  under  and  into  the  fire. 

Paper  is  coloured  with  a  great  variety  of  substances,  of  which  the  principal 
are  :  For  blue,  cobalt  blue,  ultramarine,  Derhn  blue,  indigo-carmine,  &c.  ;  for 
yellow,  chrome  yellow,  or  acetate  of  lead  and  bichromate  of  potassium,  yellow 
ochre,  yellow  ultramarine,  &c. ;  for  green,  Schweinfurt,  or  Vienna  green, 
Berlin  blue  with  chrome  yellow,  &c. ;  for  brown,  umber,  &c. ;  for  red,  madder 
lake  dissolved  in  ammonia,  red  ochre,  &c.  The  aniline  colours  are  also  used 
as  paper  dyes.  For  some  few  purposes  the  pulp  is  mechanically  mixed  with 
the  colouring  matter.  The  use  of  poisonous  colouring  matters  should  be 
absolutely  forbidden,  as  being  dangerous  and  unnecessary.  As  fine  a  green 
can  be  oljtained  now  with  harmless  colours  as  with  arsenic. 

The  use  of  paper  coloured  yellow  with  chromate  of  lead,  red  with  minium 
(red  oxide  of  lead),  or  green  with  arsenite  of  copper  has  been  specially  forbidden 
by  some  Continental  Governments  for  wrapping  roasted  chicory,  because, 
this  being  a  very  hygroscopic  substance,  the  poisonous  colouring  matters 
of  the  paper  may  get  dissolved  by  the  moisture  and  lead  to  poisoning.  The 
same  precaution  should  be  taken  with  regard  to  papers  used  for  wrapping 
sweets,  as  children  are  liable  to  lick  the  papers. 

INDIA-EUBBER  MANUFACTURE 

In  this  manufacture,  and  in  the  process  of  vulcanising,  offensive  odours 
of  sulphur  compounds  are  liberated,  intermingled  with  those  of  tar  oils, 
creosote,  &c.  These  may  be  perceived  at  some  distance  from  the  factory, 
and  are  persistent  and  disagreeable.  The  means  to  be  adopted  are  to  con- 
duct the  boiling  operations  in  covered  vessels,  to  use  a  ventilating  fan,  and  to 
pass  the  effluvia  through  a  heated  furnace. 

ANTHRAX ' 

This  disease,  which  commits  terrible  havoc  among  the  flocks  and  herds 
in  some  countries,  is  comparatively  rare  in  Eiigland.  But  there  is  some  reason 
to  believe  that  it  is  much  more  prevalent  among  our  stock  than  one  would 
suppose  from  the  official  returns  made  to  the  Agricultural  Department  of  the 
Privy  Council,  and  more  deaths  of  men  and  women  are  due  to  it  than  appear 
in  the  published  returns  of  deaths. 

All  the  more  important  domesticated  animals  are  susceptible  to  anthrax, 
including  the  cow,  sheep,  and  horse.  It  is  rare  among  pigs,  and  old  dogs 
are  little  susceptible  ;  while  puppies  take  the  disease  readily. 

Workmen  engaged  in  any  capacity  about  infected  animals,  or  the  skins, 
wool,  oftal,  &c.,  of  such  are  liable  to  infection.  Hence  it  is  most  frequently 
observed  among  herdsmen,  skinners,  men  who  unload  cargoes  of  hides, 
slaughtermen,  and  also  among  those  who  manipulate  various  wools  and  hairs, 
chiefly  foreign,  which  have  been  directly  derived  from  infected  animals,  or 
have  been  packed  with  infected  material  for  the  purposes  of  transport. 
Anthrax  prevails  extensively  in  parts  of  Russia,  Turkey,  and  Persia  (both 
'  See  Article  by  the  \vi-iter  m  the  Encijclopadia  of  Practical  Medicine.  London:  Churchill. 


OFFENSIVE  BUSINESSES  931 

Asiatic  and  European,  and  parts  of  France  and  Germany.  It  is  not  at  all 
;so  common  in  North  as  in  South  America.  The  most  dangerous  wools 
imported  into  this  country  are  from  the  districts  around  Lake  Van  and 
from  Persia. 

In  the  manipulation  of  damp  materials,  such  as  hides,  the  infection  is 
undoubtedly  acquired  by  direct  inoculation  through  breaches  in  the  skin,  and 
it  is  improbable  that  it  is,  unless  in  exceptional  cases,  acquired  by  swallowing. 
But  in  the  manipulation  of  dry  and  very  dusty  wools  and  hair  there  is 
liability  of  infection  in  any  of  three  ways — either  by  inoculation  through 
wounds  in  the  skin,  by  swallowing,  or  by  inhalation.  It  is  not  necessary 
to  assume  that  in  the  case  of  virus  which  has  been  swallowed  there  must  be 
a  wounded  surface  in  the  course  of  the  intestinal  tract,  where  absorption 
takes  place.  It  has  been  shown  by  Koch  that  the  spores  of  anthrax  may  be 
absorbed  directly  by  the  intestinal  epithelium,  and  cause  general  infection 
in  this  way.^  Although  the  bacilli  of  anthrax  are  capable  of  being  destroyed 
by  digestion,  the  spores  are  able  not  only  to  resist  the  action  of  the  gastric 
digestive  juices,  but  may  pass  with  impunity  through  the  whole  intestinal 
tract,  if  not  absorbed  into  the  tissues  en  route. 

Woolsorters'  disease,  which  has  attracted  considerable  attention,  is  so 
•characteristic  that  it  may  vath  advantage  be  referred  to  in  some  detail  as 
Illustrating  the  mode  of  infection  and  the  character  of  the  disease.  It  occurs 
as  a  local  disease,  an  external  sore,  with  or  without  general  symptoms,  or 
the  latter  being  present  there  may  be  no  external  sore. 

That  woolsorters  were  liable  at  times  to  suffer  death  and  illness  of  a 
peculiar  kind  was  long  known,  and  especially  was  this  observed  in  the 
Bradford  district  after  the  first  importation  of  alpaca,  a  material  unknown 
there  until  about  forty  years  ago.  It  was  mainly  owing  to  the  indefatigable 
-exertion  of  Dr.  J.  H.  Bell,  of  Bradford,  that  the  true  nature  of  the  disease 
was  ascertained  to  be  anthrax. 

The  woolsorter  is  a  person  who  divides  the  wool  of  a  fleece  into  *  sorts  ' 
•or  classes  of  various  quality,  the  coarser  and  finer  portions  being  placed 
together  in  separate  bundles.  For  some  purposes  a  fleece,  e.g.  of  mohair  or 
alpaca,  will  be  '  sorted  '  into  as  many  as  six  or  eight  '  sorts,'  or  as  few  as  a 
couple.  The  greater  the  number  of  sorts,  the  finer  will  be  the  character  of 
some  of  them.  Fleeces  of  English,  colonial,  and  other  sheep's  wool  are  also 
*  sorted,'  but  usually  into  but  a  small  number  of  '  sorts.' 

The  '  sorter,'  dressed  in  a  cotton  overall,  termed  in  Bradford  a  '  brat,' 
stands  at  his  work  before  a  sort  of  counter  locally  termed  a  '  sorting  board,' 
which  has  immediately  in  front  of  the  sorter  an  opening  covered  with  a 
movable  wire  grating  termed  a  'hurdle.'  The  sorting  of  the  wool  is  done 
■directly  over  the  hurdle  and  the  dust  and  other  fine  matter  fall  through  it, 
resting  on  the  bottom,  which  is  a  few  inches  beneath  the  grating  ('  hurdle  '). 
The  sorting-rooms  are  often  very  large,  the  '  sortmg-boards  '  being  placed 
along  the  walls,  opposite  the  windows.  As  many  as  thirty  to  forty  sorters 
may  be  engaged  in  one  room.  The  rooms  are  usually  bare  of  all  other  furni- 
ture than  the  '  boards  ; '  and  too  commonly  the  greater  part  of  the  floor 
space  is  occupied  with  stored  bales  of  wool. 

When  dry,  dusty  material  is  being  sorted,  such  as  alpaca,  mohair,  and 
■camel's  hair,  there  is  always  a  good  deal  of  dust  in  the  air  of  the  room ;  but 

'  This  fact  is  in  Kocli's  opinion  a  critical  objection  to  the  general  adoption  of  Pasteur's 
protective  inoculation  of  animals  against  anthrax.  He  considers  animals  may  be  pro- 
tected against  infection  arising  from  cutaneous  inoculation  ;  but  that  this  does  not  impart 
protection  against  intestinal  infection. 

3o2 


932  HYGIENE 

when  sheep's  wool  is  being  sorted  this  is  not  the  case,  owing  to  its  greasiness. 
The  prevalence  of  this  dust  may  not  only  be  judged  by  the  eyes  and  touch, 
but  in  a  room  which  is  not  kept  clean  can  be  noticed  by  the  quantities 
adherent  to  the  ceiling  and  walls. 

It  is  usual  in  some  cases  to  have  the  bales  or  large  packages  of  wool 
covered  ^\ith  coarse  sacking,  before  they  reach  the  sorting-room,  opened.  The 
contents  are  considerably  compressed  in  packing,  and  when  the  bales  are 
opened  and  the  fleeces  are  shaken  out  there  is  a  great  cloud  of  dust  raised,  if 
the  material  is  of  the  character  referred  to  (mohair,  alpaca,  &c.)  When  the 
bales  are  opened  in  the  sorting-room  under  such  circumstances,  the  efifect  is  to- 
distribute  immense  quantities  of  this  fine  dust  throughout  the  room.  Within 
the  bale  each  separate  fleece  is  made  up  into  a  kind  of  rough  bundle  apart 
from  the  others.  Even  an  inexperienced  eye  must  notice  that  some  of  these 
fleeces  or  some  parts  of  them  are  often  covered  with  a  good  deal  of  filth,, 
mud,  dung,  &c.,  though  as  a  rule  the  smell  is  not  ottensive.  There  is  the 
odour  peculiar  to  the  wool  or  hair,  but  even  in  the  case  of  bales  which  un- 
doubtedly contain  anthrax  virus  there  is  very  rarely  anything  which  could 
be  termed  a  stench. 

The  history  of  a  case  of  woolsorters'  disease  is  very  characteristic,  though 
mainly  owmg  to  the  absence  at  the  outset  of  anything  indicating  danger  to 
the  inexperienced.  The  sorter  goes  to  his  work  in  his  usual  health ;  after 
an  hour  or  so,  it  may  be,  he  feels  giddy  or  '  queer  ; '  but  believing  the  feehng 
will  pass  off  he  persists  in  working  until  at  last  he  is  obliged  to  go  home. 
'  Tightness '  in  the  chest  is  a  common  symptom  at  the  outset,  and  there  are 
generally  complaints  of  feehng  chilly — indeed,  the  patient  is  usually  convinced 
he  has  caught  cold. 

In  serious  cases  the  fatal  end  may  come  in  twenty-four  hours,  and  it 
is  rarely  postponed  beyond  three  to  four  days.  But  there  is  no  doubt  that 
many  persons  have  slight  attacks,  with  all  the  symptoms  usually  observed  in 
fatal  cases,  and  are  quite  well  in  a  lew  days. 

The  further  course  of  serious  cases  is  chiefly  marked  by  increasing 
prostration.  The  pulse  becomes  feebler  and  more  rapid,  the  breathing  slow 
and  shallow,  and  the  temperature  falls. 

The  following  are  the  precautionary  regulations  originally  drafted  by  the 
writer,  and  after  modification  agreed  upon,  as  necessary  for  the  prevention  of 
woolsorter's  disease,  by  the  Sanitary  Committee  of  the  Town  Council  of 
Bradford,  by  committees  of  the  manufacturers  and  woolsorters,  and  by  the 
coroner's  jury  upon  the  inquest  held  on  the  body  of  Isaac  Saville  in  1884  : — 

1.  All  bales  of  wool  or  hair  shall  be  opened  by  a  person  skilled  in  judging  the  con- 
dition of  the  material,  any  woolsorter  to  be  deemed  such  person  if  willing  to  perform  the' 
duty.  If  he  find  the  contents  unobjectionable  they  shall  be  sorted  in  the  ordinary  way. 
If,  on  opening  any  bale,  dead  or  fallen  fleeces  or  damaged  materials  are  found,  such  bale 
shall  be  at  once  taken  from  the  room  where  opened,  and  dealt  with  as  noxious.  All  Van, 
Persian,  damaged  wool,  fallen  fleeces,  and  foreign  skin,  wool,  or  hair,  shall  be  deemed 
noxious  and  shall  not  be  opened  in  the  sorting-room.  Noxious  wool  or  hair  shall,  before 
sorting,  be  thoroughly  saturated  with  water  and  then  washed  in  hot  suds,  rolled  and 
sorted  while  damp,  or  if  steeping  would  be  injurious  to  the  article,  or  would  render 
difficult  the  working  of  the  material,  then  it  shall  be  disinfected. 

2.  No  noxious  material  (alpaca,  pelitan,  or  East  Indian  Cashmere)  shall  be  opened 
in  the  sorting-room,  but  in  a  place  specially  set  apart  for  the  purpose,  separate  and 
distinct  from  the  sorting-room,  and  all  such  material  shall  be  opened  over  a  fan  by  a 
person  capable  of  judging  the  condition  of  the  material. 

3.  The  sorting-rooms  for  all  classes  of  mohair,  camel  hair,  Persian,  Cashmere,  and 
alpaca  shall  be  provided  with  extracting-fans  so  arranged  that  each  sorting-board  shall 
be  independently  connected  with  the  extracting-shaft,  in  order  that  the  dust  arising  fi'om 


OFFENSIVE  BUSINESSES  938 

■the  material  being  sorted  may  be  drawn  dowmoards,  and  thus  prevented  from  injuring 
ihe  sorter. 

4.  The  dust  collected  by  the  fan  must  not  be  discharged  into  the  open  air,  but  be 
received  into  properly  constructed  catch-boxes.  It  must  be  afterwards  burnt.  This  must 
be  attended  to  at  least  twice  a  week.  The  sweepings  from  fioors,  walls,  and  from  under 
the  hurdles  shall  be  similarly  treated.  AD  pieces  of  dead  skin,  scab,  and  clippings  or 
'  shearlings '  must  be  removed  weekly  from  the  sorting-room,  and  must  not  be  dealt  with 
•or  sold  until  they  have  been  disinfected. 

5.  All  bags  in  which  wool  or  hair  has  been  imported  shall  be  picked  clean  and  not 
brushed,  and  such  bags  shall  not  be  sold  or  used  for  any  other  purpose  until  they  have 
been  disinfected. 

6.  No  sorter  having  any  exposed  open  cut  or  sore  upon  his  person  shall  be  allowed 
to  sort. 

7.  A  place  shall  be  provided  in  which  the  sorters  can  leave  their  coats  outside  the 
■sorting-room,  or  in  some  suitable  place  covered  over,  during  working  hours. 

8.  Proper  provision  shall  be  made  for  the  keeping  of  the  sorters'  food  out  of  the 
:sorting-room,  or  in  a  closed  closet  therein,  during  working  hours.  No  meals  shall  be 
taken  in  the  sorting-room. 

9.  The  sorting-rooms  shall  be  well  ventilated,  by  fans  or  otherwise ;  but  as  this  cannot 
Ibe  effectually  accomplished  by  open  windows  only,  power  shall  be  employed  to  secure  down- 
ward ventilation,  so  arranged  as  to  protect  the  workmen  from  draught.  The  windows  shall 
•be  kept  open  during  meal  hours.    The  sorting-rooms  shall  be  warmed  during  cold  weather. 

10.  No  wool  or  hair  shall  be  stored  in  the  sorting-room,  unless  the  same  be  effectually 
^screened  off  from  such  room. 

11.  The  floor  of  the  sorting-room  shall  be  thoroughly  sprinkled  with  a  disinfectant, 
so  as  to  allay  dust,  and  swept  daily  after  work  is  over.  The  sorting-room  shall  be 
thoroughly  disinfected  and  the  walls  thereof  limewashed  at  least  once  a  year. 

12.  Kequisites  for  disinfecting  and  treating  scratches  and  slight  wounds  should  be  at 
hand  in  the  sorting-room,  as  thereby  fatal  consequences  may  be  avoided. 

13.  Proper  provision  shall  be  made  for  the  sorters  to  wash  in  or  near  to  the  sorting- 
jToom. 

14.  A  copy  of  these  precautionary  regulations  shall  be  hung  up  in  a  conspicuous  place 
in  every  sorting-room. 

Town  Hall,  Bkadford,  August  8,  1884. 

A  great  deal  of  benefit  has  been  derived  from  these  regulations,  imperfect 
.as  they  are.  The  necessity  of  compromise  in  getting  such  a  set  of  regulations 
agreed  to  by  persons  representing  very  diverse  interests  is  obvious,  and  such 
compromise  unavoidably  weakened  the  original  draft  proposals.  The  great 
boon  gained  was  the  recognition  of  certain  materials  as  being  dangerous,  and 
the  consequent  responsibility  attending  their  use. 

In  clause  1  it  is  obvious  that  '  any  woolsorter '  should  not  be  deemed  a 
person  skilled  in  judging  the  condition  of  wools,  &c.  The  object  of  selecting 
:a  skilled  person  is  that  he  may  be  able  to  give  notice  to  the  head  of  the  firm 
if  the  material  is  unfit  to  deliver  to  the  *  sorters  '  for  sorting.  Such  knowledge 
is  not  in  the  possession  of  '  any  sorter,'  but  only  of  skilled  and  experienced  men. 

Further,  it  would  be  much  better  if  it  had  been  left  optional  to  wash  or 
■disinfect  any  kind  of  wool,  instead  of  specifying  that  some  kinds  shall  be 
"washed,  &c.,  and  some  disinfected. 

3.  These  materials  are  specified  as  being  notoriously  dry  and  dusty.  A 
.general  regulation  applicable  to  all  dusty  material  would  be  preferable. 
There  is  no  reason  why  the  extraction  might  not  be  horizontal,  instead  of 
downwards,  if  the  circumstances  of  the  building  make  such  more  suitable. 
The  object  is  to  keep  the  objectionable  dust  from  rising. 

4.  The  general  regulation  to  burn  all  dust  is  unreasonable  and  unneces- 
rsary.  The  dust  from  such  material  might  readily  be  rendered  harmless  and 
valuable. 

5.  The  object  of  this  regulation  is  to  prevent  bags  possibly  infected  by 
ianthrax  being  sold  and  used  for  seating  chairs,  sofas,  and  other  purposes, 


934  HYGIENE 

and  to  prevent  the  creation  of  a  great  deal  of  dust  in  the  sweeping   of 
them. 

7.  The  alternative  of  keeping  the  clothes  '  in  some  suitable  place '  is 
objectionable.  It  is  understood  to  mean  inside  the  sorting-room,  and  the 
vague  phrase  '  suitable  place  '  Avill  often  mean  any  unsuitable  place.  The 
sorters'  coats,  &c.,  should  be  excluded  from  the  sorting-room. 

8.  Similarly  in  this  regulation  there  should  be  rigid  exclusion  of  food 
from  the  sorting-room. 

9.  The  warming  of  the  rooms  is  not  only  necessary  as  a  general  hygienic- 
regulation  in  the  sorting-rooms,  which  are  often  very  large  and  lofty,  but  it  is 
especially  necessary  for  sorters,  whose  fingers  may  become  numbed  with  cold, 
and  they  do  not  readily  notice  slight  cracks  and  scratches,  the  existence 
of  which  is  most  dangerous. 

10.  The  alternative  here  provided,  as  in  other  clauses,  renders  the  regula- 
tion practically  useless.     The  prohibition  was  needed — 

((()  To  prevent  danger  from  infected  wool  stored  in  the  room,  often  for 
months. 

(b)  To  prevent  sound  wool  thus  stored  from  being  infected  by  dust  from 
other  wool. 

(c)  To  prevent  the  cubic  space  required  by  the  sorters  being  unduly 
curtailed,  and  the  free  circulation  of  the  air  being  impeded. 

The  '  screening  off  from  the  room  '  may  be  effectual,  and  yet  all  the  real 
requirements  of  the  regulation  be  set  at  nought. 

THE   CUEING   OF  BACON 

There  is  one  part  of  this  business  which  is  liable  to  be  very  offensive,, 
apart  from  the  processes  with  which  it  is  often  associated,  and  which  may 
themselves  be  offensive.  This  is  the  singeing  of  the  hair  of  the  pigs  in  pre- 
paring the  flesh  for  bacon. 

After  the  pig  has  been  slaughtered,  it  is  '  scalded  '  and  Avashed,  and  then 
scraped  to  remove  the  hair,  without  singeing ;  but  sometimes  the  hair  is 
singed  before  the  scalding.  Sometimes  this  is  done,  on  a  small  scale,  with 
an  ordinary  instrument,  such  as  is  used  for  singeing  horses,  or  an  ordinary 
gas-flame  is  used.  At  other  times  the  carcase  is  placed  for  a  few  minutes 
on  a  straw  or  a  coal  fire,  or  it  may  be  suspended  in  the  chimney  so  as  tO' 
catch  the  heat  from  the  fire. 

The  most  complete  apparatus,  probably,  is  Denny's  patent  j)ig-singeing 
furnace ;  an  arrangement  by  which  with  a  revolving  apparatus  one  carcase 
after  another  is  introduced  into  the  singeing  place,  the  work  being  completed 
in  about  twenty-five  seconds,  and  the  greater  part  of  the  effluvium  passes  up' 
the  chimney. 

The  stench  from  the  burning  hair  is  very  offensive,  and  is  often  allowed 
unnecessarily  to  become  aggravated  by  the  carcase  being  left  still  smoking  on 
the  premises.  A  bucket  of  cold  water  thrown  over  it  stops  the  smell  at 
once. 

The  drying  of  bacon  is  ordinarily  effected  merely  by  hanging  it  in  a  dry 
airy  situation,  as  for  mstance  near  the  kitchen  ceiling.  On  a  large  scale 
it  is  accelerated  by  the  use  of  special  rooms  heated  to  about  95°  F.,  the  heat 
being  supplied  by  fires  of  coke,  or  smokeless  coal  in  a  fire-grate,  or  on  a  brick 
flooring  in  the  centre,  openings  being  provided  in  the  roof  or  Avails  for  the 
escape  of  smoke.  The '  smoking  '  of  the  bacon  and  hams  is  effected  by  expos- 
ing them  to  the  fumes  of  burning  wood,  above  which  they  hang,  and  the^ 


OFFENSIVE  BUSINESSES  935 

flavour  is  varied  according  to  the  wood  used.  Oak  or  elm  shavings,  or  sawdust, 
are  most  commonly  used. 

The  fumes  from  the  smoking  chambers  are  pungent,  unpleasant,  and 
may  become  a  nuisance  unless  discharged  into  a  chimney  high  enough  to 
secure  their  diffusion.  But  the  smell  of  the  singed  hair  is  the  chief  nuisance 
complained  of  in  connection  with  this  trade,  and  it  can  only  be  overcome  by 
the  process  being  conducted  in  a  closed  chamber,  and  so  that  the  fumes  shall 
be  burned,  or  condensed,  or  both,  and  then  discharged  through  a  high 
chimney. 

There  must  always  be  difficulty  in  carrying  on  this  business,  and  others 
in  which  offensive  effluvium  is  produced  in  crowded  districts,  and  it  is  just 
in  crowded  poor  places  that  such  businesses  are  most  commonly  found  in 
operation. 

Another  source  of  nuisance  connected  with  bacon-curing  is  the  brine, 
which  is  sometimes  used  too  long,  and  even  after  it  has  become  offensive  is 
often  allowed  to  stand  on  the  premises  until  it  is  quite  unendurable.  The 
mode  of  avoiding  this  nuisance  is  too  obvious  to  need  further  comment. 

The  preparation  of  American  pork  in  this  country  to  make  bacon  may  be 
a  source  of  annoyance  from  the  warm  liquor,  in  which  the  pork  is  steeped, 
undergoing  putrefaction,  and  being  discharged  into  the  drains.  This  annoy- 
ance could  be  easily  avoided.  The  process  of  preparing  bacon  from  American 
pork  consists  in  first  steeping  it  for  about  twelve  hours  in  water  to  extract 
excess  of  salt,  then  drying  it  in  a  hot,  closed  room,  warmed  by  a  charcoal 
fire,  and  subsequently  exposing  it  to  a  current  of  air. 

MANUFACTUEE    OP    HOESE-HAIR 

Horse-hair  is  chiefly  used  for  making  mattresses,  stuffing  chairs,  making 
cloth  for  covering  chairs,  sofas,  railway-carriage  seats,  brush-making,  &c. 

The  hair  used  is  by  no  means  exclusively  horse-hair,  though  generally 
known  under  that  name.  Cow-hair  is  used  for  the  same  purpose,  but  is 
generally  of  a  finer  quality  than  horse-hair.  Pig-hair  also  is  largely  used,  but 
not  for  weaving,  being  too  short.  As  the  treatment  of  all  these  hairs  is 
XDractically  the  same  from  the  sanitary  point  of  view,  they  will  be  all  mcluded 
generally  in  this  article. 

The  manes  and  tails  of  horses  are  the  parts  used,  and  the  tails  of  cows. 

Except  the  best  quality  of  horse-hair,  all  these  are  more  or  less  dusty 
and  filthy.  Sometimes  the  bales  smell  very  unpleasantly.  The  hair  has 
commonly  dung,  earth,  &c.,  attached  to  it,  and  sometimes  even  bits  of  skin 
and  even  bones  of  the  tail  will  be  found  attached. 

After  pieces  of  skin,  &c.,  have  been  detached,  the  manufacture  of  long 
hair  may  be  said  to  commence  with  the  sorting,  or  dividing  the  hair  into 
long  and  short,  coloured  and  white.  There  is  a  good  deal  of  offensive  dust 
stirred  up  during  this  process. 

The  hair  is  then  washed,  and  when  dry  is  combed,  which  straightens  it 
and  removes  short  hairs  (which  are  mixed  with  pig-hair  and  curled),  and  it 
is  then  further  divided  into  lengths,  the  longest  being  set  aside  for  weaving. 
The  coloured  hair  is  then  dyed,  the  almost  universal  colour  being  black, 
while  the  white  hair  is  bleached  by  exposure  to  the  fumes  of  burning  sulphur 
in  a  small  closed  chamber.  The  dyeing  is  usually  done  wdth  logwood  and 
protosulphate  of  iron. 

The  short  hair  is  sometimes  dyed  and  sometimes  is  not.  If  very  dirty  it 
is  teazed  and  dusted  in  a  '  willowing  '  machine,  similar  to  that  used  in  the 


986  HYGIENE 

wool  trade.  This  consists  of  a  closed  box,  within  which  revolve  one  large 
cy Under  and  usually  three  small  ones  all  being  provided  with  spikes  project- 
ing from  the  surface.  The  hair  being  fed  into  the  box,  when  the  cylinders 
revolve  it  is  tossed  about  and  opened  out,  the  lighter  dust  being  removed  by 
a  fan,  while  the  heavier  falls  to  a  false  bottom  placed  between  the  true 
bottom  and  the  cylinder.  The  tine  dust  is  commonly  discharged  into  the 
air — a  very  objectionable  custom.  The  heavier  dust  is  very  good  for  manure, 
for  which  it  is  generally  used. 

Short  hair  which  is  to  be  dyed  is  commonly  dyed  with  the  dirt  on.  Some- 
times it  is  '  ■vsdllowed  '  first.  It  is  dyed  by  being  boiled  with  logwood  in  a 
large  vat,  commonly  in  the  open,  but  (protected  from  the  rain)  by  means  of 
steam  discharged  into  the  water.  After  some  hours  sulphate  of  iron  (green 
copperas)  is  added,  the  whole  process  lasting  some  six  hours.  The  hair  is  then 
removed  to  another  vessel  and  washed,  and  if  necessary  that  which  has  not 
been  previously  '  willowed  '  is  passed  through  a  dusting  machine.  The 
liquor  was  formerly  discharged  direct  into  the  sewers  while  hot,  by  which  a 
very  offensive  smell  was  created  along  the  streets,  and  often  inside  houses, 
as  it  ran  through  the  drain-pipe.  Now  there  is  a  statutory  limit  of  80°  F., 
above  which  temperature  liquids  are  inadmissible  into  sewers. 

The  hair  is  curled  by  being  first  twisted  into  a  sort  of  rope  by  the  curling 
machine ;  by  two  subsequent  operations  it  is  further  twisted  till  it  assumes 
a  convoluted  form,  in  which  it  is  tied ;  it  is  then  steeped  in  cold  water  for 
some  hours,  and  on  removal  is  placed  in  ovens  at  a  very  high  temperature, 
after  which  the  curl  is  permanent. 

In  the  neighbourhood  of  such  works  there  is  often  great  annoyance 
created  by  the  stench  from  the  vapours  of  the  dye-vat,  and  from  the  hot 
liquor  discharged  into  the  drains.  The  former  could  be  entirely  obviated 
by  the  use  of  a  water-sealed  lid,  with  hood  and  a  flue  conducting  the 
vapours  into  a  cold-water  tank  or  scrubber.  The  discharge  of  the  vapours 
into  the  chimney  will  be  quite  ineffectual  unless  it  be  of  sufficient  height. 
The  only  efiect  of  discharging  into  a  chimney  insufficiently  high  is  that, 
instead  of  those  near  the  works  being  affected  by  the  stench,  it  will  be 
those  at  a  little  distance.  The  smell  may  extend  for  hundreds  of  yards, 
and  is  often  of  a  very  sickening  character,  causing  nausea  and  malaise, 
and  rendering  it  impossible  to  open  doors  or  windows. 

The  remedy  for  the  nuisance  arismg  from  the  liquor  discharged  into  the 
drams  is  not  to  discharge  the  liquor  into  the  drains  till  cold,  a  precaution  which 
should  be  taken  with  all  fluids  discharged  into  the  sewers  in  large  quantity. 

A  more  serious  evil  is  infection  with  anthrax  (knoA\'ii  as  woolsorters' 
disease,  charbon,  malignant  pustule),  which  undoubtedly  occurs  at  times,  and 
probably  more  frequently  than  is  suspected.  It  is  due  to  infection  by  means 
of  virus  attached  to  the  hair  from  animals  which  have  suffered  from  the 
disease.  There  seems  no  reason  why  all  dirty  hair  should  not  be  boiled 
and  dyed  before  sorting,  which  would  obviate  the  dangers  of  the  dusty  stage, 
and  probably  disinfect  thoroughly.  Little  is  to  be  expected  from  the  sug- 
gested use  of  a  respirator  during  sorting,  because  (Ij  the  disease  is  by  no 
means  always  taken  by  inhalation,  but  frequently  by  inoculation  through 
scratches,  and  (2)  workpeople  will  not  wear  respirators  of  any  form  so  far 
known,  findmg  them  too  unpleasant.  (Cf.  Precautions  agamst  Woolsorter's 
Disease,  p.  932.) 


OFFENSIVE  BUSINESSES  937 


B.    BUSINESSES    IN    WHICH   KNOWN     GASES    OB    VAPOURS    OF 
MINERAL   SUBSTANCES  ARE  EVOLVED 

MORBID    EFFECTS   ARISING   FROM   THE   INHALATION   OF   GAS 

Before  referring  to  the  notable  and  unmistakable  reactions  occurring  in 
the  body  in  consequence  of  the  inhalation  of  toxic  gases,  a  word  may  be  said 
in  reference  to  the  action  of  certain  gases,  usually  termed  indifferent — i.e. 
those  which,  when  mixed  in  certain  proportions  with  oxygen,  do  not  cause  any 
decided  morbid  symptoms,  provided  the  proportion  of  oxygen  be  not  too  small. 

Those  most  deserving  attention  in  this  group  are  nitrogen,  hydrogen, 
marsh  gas,  and  olefiant  gas  (respectively  termed  in  modern  nomenclature 
methyl  hydride,  and  ethylene). 

Although  the  continued  inhalation  of  a  mixture  of  such  gases  with 
oxygen  may  give  rise  to  abnormal  symptoms,  especially  if  the  proportion  of 
oxygen  be  low,  it  is  not  at  all  clear  that  the  deficiency  of  oxygen  is  not  the 
source  of  the  mischief,  rather  than  the  presence  of  the  other  gases. 

Methyl  hydride  may  certainly  be  regarded  as  a  truly  indifferent  gas.  It 
seems  that  olefiant  gas  (ethylene)  does  possess  certain  toxic  effects  ;  at  least 
certain  unpleasant  results  of  breathing  the  air  of  mines  (coal)  where  it  existed 
have  been  attributed  to  its  action,  though  by  no  means  with  certainty. 

A  rabbit  confined  in  an  atmosphere  containing  30  per  cent,  of  the  gas 
became  narcotised  in  thirty  minutes,  its  respiration  having  become  tranquil 
after  a  period  of  excitation.  The  animal  recovered  completely  after  one 
hour.  A  pigeon  exposed  to  a  similar  atmosphere  died.  It  exhibited  convul- 
sive movements  with  its  wings,  difficult  breathing,  and  lay  with  its  head  on 
one  side ;  the  pupils  were  dilated  and  the  temperature  diminished.  The 
autopsy  showed  the  heart  and  veins  filled  with  fluid  blood  ;  the  lung  surface 
bright  red,  with  some  brownish  marbling  ;  the  cut  surface  showed  black 
hffimorrhagic  spots. 

Ethylene  is  distinctly  an  anaesthetic  gas.  The  morbid  condition  known 
as  '  miner's  anaemia  '  has  been  supposed  to  be  due  to  the  continued  respiration 
of  air  containing  a  considerable  proportion  of  ethylene.  It  is  more  probable 
that  it  is  only  one  of  the  factors  which  leads  to  this  serious  and  mysterious 
morbid  condition.  When  one  considers  the  conditions  under  which  a  miner 
spends  his  working  hours,  in  almost  absolute  darkness,  in  an  atmosphere 
too  often  charged  with  moisture,  or  dust,  containing  many  abnormal  con- 
stituents besides  the  gas  in  question  ;  further,  when  one  takes  into  considera- 
tion the  nature  of  the  work,  the  position,  often  most  constrained,  lying  on 
the  back  or  side,  &c.,  it  will  not  seem  surprising  that  some  constitutions 
should  suffer.  Among  the  most  notable  pathological  phenomena  of  this 
disease  are  the  quantitative  diminution  of  the  blood-corpuscles,  and  their 
greater  or  less  disintegration,  as  well  as  the  diminished  secretion  of  sugar  in 
the  liver. 

MORBID   CONDITIONS   DUE   TO   THE   INHALATION   OF   IRRESPIRABLE 

GASES 

It  is  not  possible  to  draw  too  exactly  the  line  which  separates  irrespirable 
gas  from  those  which  are  directly  poisonous.  By  the  former  are  meant  gases 
which  produce  readily  or  immediately  great  irritation  of  the  respiratory 
passages,  generally  leading  in  small  quantity  to  cough,  and  in  greater  quantity 
to  spasmodic  closure  of  the  larynx.     This  salutary  closure  of  the  respiratory 


938  HYGIENE 

tract  prevents  the  further  entrance  of  the  noxious  agent.  Of  the  rapid  action 
of  sulphurous  acid  gas,  one  of  those  included  in  the  category,  the  writer  can 
speak  from  personal  experience. 

He  was  about  to  disinfect  the  operating-room  of  a  hospital  to  which  he 
was  surgeon,  and  had  procured  an  alcoholic  solution  of  sulphurous  acid  for 
the  purpose.  The  room  had  been  prepared  by  the  closure  of  all  orifices, 
except  the  door  by  which  exit  was  to  be  made  after  the  disinfectant  had 
been  poured  on  the  dishes  arranged  for  it.  At  the  last  moment  the  solution 
of  sulphurous  acid  was  poured  out  on  the  dishes,  and  the  writer  hastened  to 
the  door,  but  before  reaching  it  he  fell,  completely  overcome  by  the  fumes. 
Had  his  fall  not  alarmed  the  nurses,  who  hurried  to  his  help  and  dragged 
him  from  the  room,  the  result  would  probably  have  been  fatal. 

Sulphurous  acid  (sulphur  dioxide)  comes  into  consideration  in  a 
variety  of  industries,  in  a  greater  or  less  degree — e.g.  in  the  manufacture  of 
sulphuric  acid,  alum,  glass,  catgut ;  in  the  manufacture  of  '  tin  ' — that  is, 
really  the  tinning  of  thin  sheets  of  iron  ;  in  bleaching  of  certain  kinds, 
such  as  wool,  cotton,  silk,  straw,  &c. ;  in  the  preparation  of  certain  kinds  of 
*  preserved '  foods  (fruits,  vegetables,  meat,  &c.)  and  on  a  very  large  scale  in 
the  preparation  of  hops.  These  last  are  'sulphured'  to  make  them  keep 
Avhen  dried.  Wherever  coal  is  burned,  or  minerals  containing  sulphur  are 
roasted,  SO2  is  also  produced. 

No  very  specific  characters  can  be  attributed  to  the  effects  of  inspired 
sulphur  dioxide.  Animals  experimentally  exposed  to  its  action  exhibit  rest- 
lessness, followed  by  depression  and  convulsions,  which  terminate  fatally. 
The  heart  and  great  vessels  are  found  after  death  charged  with  blood,  and 
the  muscular  irritability  is  diminished  ;  the  blood  assumes  a  dirty  brownish- 
red  colour.  Accordmg  to  Hirt,  sulphur  dioxide  has  a  direct  paralysing  action 
on  the  vagus  nerve,  and  affects  the  respiratory  centre,  sometimes  as  a 
stimulant,  sometimes  as  a  paralyser,  death  resulting  from  paralysis  of  this 
centre. 

Weak  dilutions  of  the  gas  (5-15  per  cent.  SO^)  paralyse  the  vasomotor 
centre  rapidly,  while  strong  ones  (50-70  per  cent.  SO.,)  produce  this  as  a 
secondary  effect  after  a  preceding  stage  of  excitement. 

The  morbid  effects  produced  by  continued  inhalation  of  SOo  in  weaker 
dilution  (e.g.  4-6  per  cent.)  seem  at  first  to  show  themselves,  not,  as  might  be 
expected,  in  the  respiratory  organs,  although  acute  catarrh  of  the  respiratory 
organs  is  common  enough,  but  in  those  of  digestion.  Even  in  a  much  weaker 
dilution  than  that  named  the  depraved  air  causes  an  acid  taste  in  the  mouth, 
acid  eructations,  anorexia,  irregularity  of  the  bowels,  and,  as  might  be  expected, 
effects  on  the  general  health  corresponding  to  these  evidences  of  impaired 
digestion.  Hirt  states  that  sometimes  increased  activity  of  the  digestive 
organs  is  observed  where  there  is  only  a  weak  dilution  of  the  gas,  but  others, 
especially  Eulenberg,  deny  this. 

Hirt  lays  especial  stress  on  one  result  of  his  experience — \\z.  that  most 
commonly  the  continued  inhalation  of  a  weak  dilution  of  SO2  may  not  be 
directly  capable  of  con\'iction  of  causing  disease  of  the  respiratory  tract,  but 
that  it  is  eminently  calculated  to  produce  a  morbid  condition  of  that  portion 
of  the  body,  which  ultimately  leads  with  great  certainty  to  disease. 

In  the  bleaching  of  straw  hats,  these  are  loosely  packed  in  a  box  and 
exposed  to  the  fumes  of  SO2  for  some  hours. 

That  workmen  who  are  exposed  in  a  confined  space  to  exhalations  which, 
when  they  escape  into  the  open  air,  kill  the  plants  in  the  neighbourhood,  and 
cause  great  annoyance  to  those  li%dng  near  at  hand,  should  suffer  in  their 
health  is  what  must  be  expected.     Although  it  may  be  impossible  to  apply  a 


OFFENSIVE  BUSINESSES  939 

chemical  test,  and  show  by  a  chemical  reaction  that  the  SO^  is  the  cause, 
still  common-sense  and  humanity  alike  claim  for  the  workmen  in  such  a  case 
the  protection  of  the  law. 

It  is  an  obvious  suggestion  that  workshops  where  fumes  of  this  character 
are  produced  should  be  under  strict  sanitary  supervision,  and  that  they  should 
be  so  situated  as  not  to  prove  a  nuisance  or  injurious  to  neighbouring 
houses. 

Wherever  workmen  are  unavoidably  exposed  to  SO.^,  it  is  most  important 
to  employ  means  to  secure  its  being  prevented  accumulating  in  the  place  by 
proper  ventilation,  which  will  ensure  the  exit  of  the  gas  and  the  supply  of 
pure  air. 

Should  a  dangerous  amount  of  the  gas  be  present  in  any  place,  various 
means  may  be  employed  to  diminish  the  danger.  First,  of  course,  comes 
free  ventilation  ;  but  in  addition  it  will  be  useful  to  use — 

(1)  Absorbent  media,  such  as  water  sprinkled  about,  alkalies,  &c  :  milk 
of  lime  is  very  useful ;  metallic  oxides — e.g.  those  of  copper  or  iron  ;  organic 
substances — e.g.  sawdust  well  warmed  is  also  an  excellent  absorbent. 

(2)  Oxidising  media — e.g.  lead  dioxide,  manganese  dioxide.  Sulphuretted 
hydrogen  also  reacts  with  SO2,  with  production  of  sulphur. 

CHLORINE 

Chlorine  is  used  in  various  forms  in  enormous  quantities  in  the  arts.  As 
a  bleaching  agent  it  is  largely  used  for  the  rapid  bleaching  of  cotton  and 
linen  goods  (but  not  of  woollen,  silk,  or  straw '),  bones,  ivory,  glycerine,  also 
in  certain  kinds  of  printing  on  stuffs  (Turkish  red),  and  dyeing. 

Chlorine  is  usually  developed  from  manganese  dioxide,  sodium  chloride, 
and  sulphuric  acid,  the  sodium  combining  with  the  sulphuric  acid  and  liberat- 
ing the  chlorine.  The  prevention  of  the  escape  of  chlorine  from  the  vessel 
is  a  most  important  matter  for  the  workmen. 

Inhalation  of  chlorine  for  some  time  produces  effects  very  similar  to  the 
inhalation  of  ammonia.  But  large  quantities  in  the  air  (10-20  per  cent, 
chlorine)  quickly  leads  to  inflammatory  action  in  the  respiratory  tract,  and 
even  extensive  pneumonia.  Spasm  of  the  glottis  occurs,  but  soon  relaxes, 
and  is  certainly  not  the  cause  of  death,  which  seems  rather  due  to  paralysis 
of  the  heart.  A  rabbit  placed  in  an  atmosphere  of  chlorine  in  three  minutes 
became  dizzy  and  fell ;  and  death  ensued  in  five  minutes,  with  slight  convul- 
sive movements  of  the  extremities  and  deep  spasmodic  inspirations.  The 
brown-red,  black  spotting  of  the  lungs  is  characteristic  of  death  from  inhala- 
tion of  chlorine.  The  finer  bronchi  are  filled  with  a  froth,  and  the  mucous 
membrane  of  the  trachea  and  bronchi  are  discoloured  brown.  The  lungs 
may  be  in  part  condensed  and  firm  to  the  touch.  The  blood  is  of  a  thick  con- 
sistence, and  is  sometimes  granular. 

According  to  Hirt,  chlorine  workers  suffer  much  in  general  health,  from 
450  to  500  per  1,000  requiring  treatment  during  the  year  for  internal  ailments, 
not  from  actual  chlorine-poisoning,  which  cannot  be  said  to  exist,  but  from 
results  of  its  irritating  action.  The  respiratory  organs  are  the  first  to  suffer, 
the  irritating  gas  causing  cough,  sneezing,  hoarseness,  great  irritation, 
and  even  inflammation  of  the  larynx.  The  coughing  fits  may  be  so  violent 
as  to  lead  to  bleeding  of  the  nose,  and  even  fatal  haemorrhage  from  the  lungs. 
The  action  of  the  gas  on  the  mucous  membrane  of  the  nose  and  mouth  may 
lead  to  loss  of  both  smell  and  taste.     The  general  discomfort  may  increase 

'  See  abo^^ 


940  HYGIENE 

till  giddiness  occurs,  and  this  may  end  in  sudden  asphyxia,  which,  however, 
usually  terminates  on  exposure  to  a  plentiful  supply  of  fresh  air.  Death 
under  such  circumstances  is  not  common. 

Still  though  such  fatal  occurrences  are  rare,  general  bad  effects  result 
from  continual  exposure  to  an  atmosphere  laden  with  chlorine.  The  work- 
men lose  their  healthy  colour,  age  quickly,  and  look  pale  or  greenish. 

The  commonest  form  of  internal  disease  among  workmen  engaged  in 
this  trade  is  acute  catarrh,  which  may  end  in  acute  pneumonia.  Where 
other  diseases,  or  tendency  to  disease,  exists  (e.g.  phthisis)  it  is  tolerably 
certain  that  the  continued  irrritation  of  the  respiratory  tract  will  maintain  a 
condition  highly  favourable  to  the  progress  of  the  disease. 

As  a  protective,  the  inhalation  of  alcoholic  solution  of  ammonia  has  been 
recommended.  Eulenberg  recommends  in  preference  the  carrying  of  sponges 
moistened  with  alcohol  before  the  mouth  and  nose,  and  rightly  condemns 
the  inhalation  of  anihne  (recommended  by  Bailey).  The  use  of  the  latter  may 
prevent  the  pungent  smell,  and  irritation  of  the  throat,  but  by  the  formation 
of  cliloraniUne  may  do  serious  harm  to  the  workmen. 

The  frequent  occurrence  of  pyrosis  among  the  workmen  is  due,  no  doubt, 
to  the  actual  swallowing  of  abnormally  acidulated  saliva.  The  indigestion 
•due  to  this  excess  is  responsible  for  much  of  the  ill-effect  above  referred  to 
as  being  observed  among  workers  where  chlorine  is  produced.  Careful  atten- 
tion to  dietary  is  obviously  one  of  the  hygienic  regulations  most  needed. 

BRICK-MAKING 

Bricks,  tiles,  &c.,  are  formed  from  a  great  variety  of  clays,  differing 
greatly  in  physical  character.  The  clay  has  to  be  ground  and  mixed  with 
water,  after  which  it  is  allowed  to  dry  to  the  proper  consistence.  Sand, 
chalk,  ashes,  or  fine  coal,  are  added  sometimes,  and  even  the  miscellaneous 
cUhris  of  dustbins.  When  bricks  are  to  be  burned  in  a  kiln  combustible 
matter  is  usually  not  added  to  the  clay. 

Bricks  are  burned  either  in  '  clamps  '  or  '  kilns.'  The  former  method 
consists  in  building  the  bricks  into  a  pile  8  to  10  feet  high,  with  alternate 
layers  of  fine  breeze  (cinder),  air-passages  being  left  at  suitable  intervals. 
When  a  clamp  (or  pile)  of  sufficient  size  has  been  made,  which  may  mean 
half  a  miUion  to  a  million  and  a  half  bricks,  fires  are  lighted  around  it,  by 
which  the  breeze  is  ignited,  and  by  this  means  the  combustible  matter  in  the 
bricks  themselves  is  also  put  into  a  state  of  slow  combustion.  When  this 
has  been  all  consumed  the  combustion  ceases. 

When  the  bricks  are  burned  in  a  kiln,  fuel  is  used  in  much  larger  quanti- 
ties than  in  the  '  clamp '  process.  In  some  kilns  the  top  is  open,  and  the 
•effluvium  escapes  ;  in  others  it  is  closed,  and  the  smoke,  vapours,  and  gases 
escape  by  a  chimney.  In  the  former  the  bricks  are  built  up  pretty  much  as 
in  the  clamp  process,  but  a  considerable  space  is  left  at  intervals  between  the 
bricks  to  serve  as  receptacles  for  fuel,  some  of  the  orifices  being  closed  by 
plaster  to  retain  the  heat  at  a  certain  stage.  It  takes  about  12  to  14  days  to 
complete  the  making  of  bricks  by  this  process.  The  closed  kiln  consists  of 
a  low  brick  building,  with  openings  at  the  top  and  sides  for  filling,  stoking,  &c. 

Within  tbese  the  '  green  '  bricks  are  built  up,  and  they  are  so  arranged  that 
when  at  work  the  draft  ascends  inside  along  the  walls  and  descends  through 
the  bricks  to  the  flue  leading  to  the  cbimney,  the  flue  being  underground  ; 
in  other  forms  the  chimney  rises  from  the  centre  of  the  oven.  The  Hof- 
mann  circular  kiln  has  acquired  a  deservedly  wide  reputation  as  one  of 
the  best  for  large  work,  as  it  requires  little  fuel  and  burns  it  thoroughly. 


OFFENSIVE  BUSINESSES  941 

For  smaller  works  other  forms  of  close  kiln  are  in  use,  which  are  a  great 
improvement  on  the  clamp  process. 

There  is  no  town  which  is  growing  quickly  where  there  has  not  been 
trouble  from  the  effluvium  arising  from  brick-making.  That  given  off  by 
the  clamp  process  is  sometimes  very  offensive,  the  degree  depending  a  good 
deal  on  the  nature  of  the  material,  the  proportion  of  organic  matter,  and 
its  character.  The  continuous  issue  of  smoke  at  such  a  low  level  and  its 
smell,  which  is  sometimes  pungent  and  very  disagreeable,  are  the  chief  sources- 
of  complaint.  Sulphurous  acid  may  be  present  in  a  very  appreciable  degree. 
At  the  commencement  of  the  burning  the  emanations  are  charged  with 
watery  vapour,  and  often  with  sulphuretted  hydrogen,  carbonic  acid,  car- 
bonic oxide,  carburetted  hydrogen,  ammonia,  &c.  Offensive  empyreumatic 
gases  are  sometimes  largely  present  also,  arising  from  the  combustion  of 
organic  matter.  When  bricks  or  pottery  are  glazed,  the  nuisance  becomes 
much  more  serious  both  for  the  workmen  and  the  neighbours.  If  salt  is 
used,  chlorme  is  given  off  ;  if  sulphide  of  lead  be  employed,  the  danger  arising 
from  the  lead  and  the  sulphur  fumes  is  very  serious. 

This  last  source  of  nuisance  could  easily  be  removed  by  avoiding  the  use 
of  organic  debris  entirely,  and  using  only  small  coke.  The  smoke  nuisance 
is  largely  due  in  this  case,  as  in  ordinary  boiler  fires,  to  the  utter  recklessness 
with  which  the  stoking  is  neglected,  the  red-hot  and  smokeless  fires  being 
from  time  to  time  damped  down  with  coal  heaped  on,  instead  of  small  quanti- 
ties being  put  on  at  short  intervals.  The  watering  of  the  coal  before  it  is 
put  on  the  fire  has  a  very  advantageous  effect  in  diminishing  the  smoke 
nuisance. 

The  nuisance  is  sufficient  to  cause  actual  fainting,  oppression  of  breath- 
ing, and  other  serious  symptoms  in  persons  much  exposed  to  it. 

MANUFACTUEE    OP   POETLAND   CEMENT 

Portland  and  Eoman  cements  are  two  kinds  of  hydraulic  cements  manufac- 
tured in  this  country.  Genuine  Eoman  cement  is  made  from  pozzuolana,  a 
ferruginous  volcanic  ash  from  Vesuvius  and  other  Italian  volcanoes  mixed 
with  lime ;  or  from  a  combination  of  lime  and  trass,  a  kind  of  pumice  from 
the  Eifel  district  of  the  Ehine.  This  material  simply  reqmres  grinding.  In 
this  country  cement  is  made  from  the  septaria^  from  the  London  clay  and  the 
Lower  Lias  formations,  from  cement  stone  of  the  Upper  Lias,  and  from  shale 
beds  of  the  Kimmeridge  clay.  It  is  also  made  by  the  calcination  of  mixtures 
of  lime  and  ferruginous  clay.  The  septaria  are  calcined  in  open  kilns,  like 
limestone,  but  the  process  does  not  give  rise  to  much  nuisance. 

The  manufacture  of  Portland  cement,  however,  causes  a  serious  nuisance 
unless  conducted  with  special  precautions.  It  is  made  usually  from  a  mix- 
ture of  about  eighty  parts  of  chalk  or  rich  lime  and  twenty  of  clay  or 
alluvial  mud.  The  materials  are  mixed  wet,  then  dried,  calcined,  and  pul- 
verised. The  clay  used  often  contains  much  peaty  matter,  and  even  more 
offensive  materials,  which  give  rise  ultimately  to  the  great  nuisance  com- 
plained of. 

The  ingredients  having  been  well  mixed  and  brought  to  the  proper  con- 
sistency (in  which  state  it  is  known  as  '  slurry '),  are  dug  out  and  dried,  usually 
on  iron  plates,  heated  either  indirectly  by  flues  from  coke  fires,  or  directly  by 
the  fires  themselves.     When  dried  the  '  slurry  '  is  placed  in  an  ordinary  kihi, 

'  Nodules   of    clay,   ironstone,    &c.,  internally   divided   into  angular   compartments 
(septa)  by  fissures,  which  are  usually  filled  with  a  calcareous  spar. 


942  HYGIENE 

like  that  used  foi*  lime-burning,  and  calcined  ;  alternate  layers  of  '  slurry ' 
and  coke  being  deposited  in  the  kihi,  and  then  lighted,  the  '  charge  '  taking 
usually  (according  to  size)  some  three  to  five  days  to  burn  out. 

The  nuisance  complained  of  is  due  partly  to  smoke  and  vapour,  partly  to 
the  smell,  which  is  somewhat  like  that  caused  by  brick-burning,  but  has  also 
a  strong  similarity  to  the  odour  of  burning  bones  or  other  organic  matter, 
the  character  of  the  smell  varying  greatly,  from  very  slight  to  very  bad, 
according  to  the  nature  of  the  clay  used. 

People  exposed  to  these  effluvia  complain  of  a  nasty  taste  in  the  mouth, 
often  of  an  acid  character,  of  a  dryness  of  the  mouth  and  throat,  and  even  of 
vomiting  and  oppression  of  breathing. 

The  smell  arises  during  the  drying  of  the  '  slurry,'  but  then  it  is  very 
slight  compared  with  what  is  emitted  during  the  calcining.  It  has  been 
found  that  sulphuretted  hydrogen  and  compounds  of  cyanogen,  probably  a 
cyanide  of  ammonium  or  sodium,  a  sulphocyanide,  chloride  of  sodium,  and 
empyreumatic  compounds  are  given  off  during  this  process.  The  common 
salt  given  off  in  a  state  of  very  fine  division  increases  the  annoyance  from  the 
more  serious  gases  given  oft'.  The  effluvia  vary,  as  has  been  stated  above, 
considerably  in  different  places,  and  do  not  everywhere  contain  all  these 
dangerous  and  offensive  ingredients. 

The  best  mode  of  preventing  the  danger  is  to  pass  the  vapour  collected 
from  the  kiln  by  a  suitable  hood  and  flue,  assisted  by  a  fan  if  necessary, 
through  the  furnace,  and  thence  into  a  tall  chimney.  Attempts  have  been 
made  to  deal  with  the  nuisance  by  condensing  and  washing  the  fumes  in  a 
cold-water  scrubber,  but  not  ahvays  successfully^ 

LIME-BUENING 

Lime-burning  consists  in  heating  limestone  or  chalk  in  a  kiln,  which 
causes  it  to  decompose  and  form  lime  (quickhme)  and  carbon  dioxide. 
Lime  is  not  found  free  in  nature,  but  it  exists  in  enormous  quantities  in 
the  form  of  carbonate. 

The  ordinary  open  lime-kiln  is  practically  a  sort  of  chimney,  lined  with 
firebrick  or  reh'actory  stone,  and  narroAving  to  the  bottom,  where  the  lime 
is  discharged.  It  is  charged  from  the  top  with  alternate  layers  of  fuel  and 
limestone  or  chalk,  and  is  fired  from  below.  Such  a  kiln  may  be  worked 
contmuously,  more  layers  of  fuel  and  hmestone  being  charged  above  as  the 
lime  is  withdrawn  below. 

Closed  kilns  are  also  sometimes  used,  similar  to  the  Hoffmann  brick- 
kilns (q.v.) 

The  nuisance  from  lime-burning  is  due  partly  to  the  carbon  dioxide 
evolved  from  the  limestone  or  chalk  as  well  as  from  the  coal,  partly  to  the 
smoke,  and  also  to  the  offensive  fumes  evolved  from  the  fuel,  which  is  burned 
slowly,  and  not  briskly  as  in  an  open  fire.  Carboniferous  limestone  causes 
a  much  greater  nuisance  than  other  materials  used  for  lime  production. 

Death  may  arise  from  continued  exposure  to  the  fumes,  as  when  persons 
lie  down  to  warm  themselves,  fall  asleep,  and  die.  Continued  exposure  to 
the  fumes  leads  to  very  serious  symptoms — debility,  loss  of  appetite,  great 
drowsiness,  and  general  nervous  derangement.  The  results  are  probably 
due  10  the  carbonic  oxide. 

Much  of  the  nuisance  is  due  to  the  quality  of  the  fuel,  which  should  be 
good  coal  or  coke  (not  inferior  shaly  material).  Inferior  coal  causes  greater 
nuisance,  greater  waste,  and  makes  worse  lime.  Besides  the  use  of  better  fuel, 
a  tall  chimney  should  be  used  to  discharge  the  fumes  at  a  sufficient  height. 


OFFENSIVE  BUSINESSES  943 

Spencer's  patent  kiln  consists  of  two  egg-shaped  chambers,  one  above  the 
other  and  communicating  one  with  the  other.  The  hmestone  is  charged  in 
at  the  top,  and  the  fuel  by  openings  made  lower  down.  The  heat  from  the 
lower  chamber  warms  the  stove  in  the  upper  before  it  descends  into  the 
calcining  chamber. 

CAEBONIC    OXIDE     (Cai!i;on    Monoxide,    CO) 

This  gas  is  formed  when  carbon  burns  in  a  scanty  supply  of  air.  It  is 
a  colourless,  tasteless,  and  odourless  gas,  rather  lighter  than  air  (sp.  gr. 
=  0"97).  It  is  present  in  ordinary  coal  fires,  the  vapour  of  burning  charcoal 
(from  0-34  to  2*54  per  cent.),  in  ordinary  illuminating  coal  gas  and  '  water- 
gas,'  and  in  the  gases  resulting  from  explosions  of  gunpowder  ;  it  is  given 
out  in  large  quantities  in  the  smelting  of  iron  ores,  in  the  making  of  coke 
and  of  wood  charcoal.  It  is  a  deadly  poison  when  inhaled,  all  the  more 
dangerous  in  that  it  indicates  its  presence  in  no  way  to  the  sense  of  sight, 
taste,  or  smell,  is  not  irritating  to  the  respiratory  or  digestive  organs,  and 
that,  exercising  a  narcotic  and  paralysing  effect,  it  lulls  the  sensations  and 
causes  insensibility  without  arousing  any  desire  or  effort  to  escape  the  danger. 

It  is  not  often  that  accidents  arise  from  inhalation  of  pure  carbonic  oxide  ; 
its  fatal  effects  are  almost  always  observed  after  absorption  of  a  mixture  of 
CO  along  with  other  gases,  most  commonly  with  coal  gas  or  charcoal 
vapour  (which  is  largely  a  mixture  of  CO2  and  CO),  CgH^  (defiant  gas, 
heavy  carburetted  hydrogen),  aqueous  vapour,  partially  deoxidised  air,  &c. 
The  abstraction  of  the  CO2  from  this  mixture,  of  which  it  forms  a  large  part, 
does  not  in  the  least  deprive  it  of  its  poisonous  characters,  which  are  there- 
fore undoubtedly  due  to  carbonic  oxide.  It  is  present  in  the  vapours  from 
blast-furnaces,  along  with  CO2 ;  and  fatal  results  have  been  caused  by 
inhaling  it  in  the  vapours  from  smouldering  ashes.  In  the  case  of  ordinary 
illuminating  gas,  which  is  also  a  mixture  of  gases  in  variable  proportions, 
the  same  dangerous  element  predominates,  being  present  to  a  varying  pro- 
portion (4  to  6  per  cent.).  The  presence  of  the  other  constituents  of  coal  gas 
in  the  inspired  air  of  a  room  no  doubt  assists  in  rendering  the  action  of 
the  carbonic  oxide  more  marked,  and  the  presence  of  0*53  per  cent,  will  pro- 
duce symptoms  of  intoxication,  while  1*5  per  cent,  will  cause  the  death  of 
animals  experimented  on. 

The  so-called  '  water-gas,'  which  has  come  much  into  use  of  late  years, 
mainly  for  heating  purposes,  consists  mainly  of  carbonic  oxide  and  hydrogen, 
the  former  usually  forming  one-third  by  volume,  or  even  40  per  cent.  It 
is  developed  by  the  action  of  glowing  carbon  on  superheated  steam.  The 
great  danger  arising  from  the  nature  of  this  gas,  and  the  absence  of  odour 
to  indicate  its  escape,  have  led  to  some  strong- smelling  gas,  e.g.,  sul- 
phuretted hydrogen,  mercaptan,  ethyl  hydrosulphide,  or  pyridine,  being 
mixed  with  it  to  serve  as  an  indicator.  Two  deaths  were  caused  at  a 
manufactory  in  Leeds  in  1889,  owing  to  the  escape  of  this  gas,  which  was 
used  for  heating  purposes,  through  a  stopcock  not  bemg  properly  turned  off. 

When  gunpowder  is  exploded  the  relative  quantity  of  the  gases  found 
vary  according  to  the  proportion  of  the  various  constituents,  and  also 
according  to  the  pressure.  The  carbon  dioxide  increases  with  the  pressure, 
while  the  carbon  monoxide  diminishes.  According  to  Eoscoe  and  Schorlem- 
mer,  the  proportion  of  CO  and  CO2  present  in  different  kinds  per  100  was  as 
follows : — 

No.  1        No.  2        No.  3        No.  4 
Carbon  monoxide    .         .         .       0-94  1-18  1-47  2-64 

Carbon  dioxide        .        .        .     20-12        22-47        21-79         17-39 


944  HYGIENE 

Exposure  to  the  action  of  gunpowder-vapour  (mine  gas)  has  heen  linown 
to  have  fatal  effects. 

Carbon  monoxide  when  inhaled  may  cause  death  by  acute  poisoning  in  from 
a  few  minutes  to  forty-eight  hours,  or  it  may  induce  chronic  intoxication 
lasting  weeks  or  months,  when  it  is  inhaled  in  small  quantities  for  a  con- 
siderable time — e.g.  from  charcoal  fumes  or  coal  gas.  An  atmosphere  con- 
taining 5  to  6  per  cent,  of  CO  will  kill  animals,  and  10  per  cent,  is  very  fatal. 
Its  poisonous  effects  are  increased  by  the  presence  of  COj.  An  atmosphere 
containing  only  0*5  per  cent,  of  CO  proved  fatal  to  a  dog  when  5  per  cent. 
of  CO 2  was  present,  neither  gas  being  present  in  a  quantity  which  by  itself 
would  be  fatal. 

The  cause  of  death  is  a  true  poisoning,  and  is  not  merely  to  be  regarded 
as  due  to  a  deficiency  of  oxygon  in  the  air.  The  carbonic  oxide  combines 
with  the  Inemoglobiii  of  the  blood.  The  union,  however,  is  of  such  a 
character  that  the  carbonic  oxide  can  be  abstracted  by  pumping. 

The  appearance  of  the  blood  in  cases  of  poisoning  by  this  gas  is  very 
peculiar  and  characteristic  :  it  is  of  a  bright  cherry-red,  and  retains  this 
colour  sometimes  for  months.  AVhen  examined  by  the  spectroscope  it  shows 
also  a  characteristic  reaction.  Carbonic-oxide  hemoglobin  shows  two  absorp- 
tion bands  between  the  D  and  E  lines,  and  is  irreducible  by  ammonium  sul- 
phide. This  spectrum  is  entirely  different  from  that  of  blood  altered  by 
dyspnoea,  involving  insufficient  oxidation,  with  retention  of  carbon  dioxide. 
Even  in  the  most  acute  cases  of  dyspnoea,  the  two  characteristic  bands  of 
oxidised  h!T?moglobin  never  disappear. 

The  earhest  symptoms,  where  the  patient  is  not  acutely  and  suddenly 
poisoned,  are  nervous  headache,  giddiness,  specks  seen  before  the  eyes,  and 
sometimes  hypertesthesia  of  the  skin  ;  the  giddiness  may  terminate  in  complete 
unconsciousness  and  anaesthesia,  if  the  absorption  of  the  poison  be  continued. 
Later  there  is  nausea  and  vomiting.  The  pulse,  which  was  at  first  accele- 
rated, becomes  slower,  and  the  respiration  also.  Sometimes  convulsions 
occur.  Paralysis  of  the  sphincters  is  observed  with  more  serious  nervous 
symptoms,  as  well  as  the  appearance  of  sugar  in  the  urine.  The  prognosis  is 
doubtful ;  if  the  unconsciousness  continues  for  some  time  it  becomes  very 
grave. 

Difference  in  SymjJtoms  of  Poisoning  by  Carbonic  Oxide  and  Carbon 

Dioxide 
Carbonic  Oxide.  Carbon  Dioxide. 

Absence  of  dyspnoea.  Dyspnoea. 

Muscular  weakness  (paresis),  coma  Muscular  debility.     Deep  coma. 

slight  or  absent. 
Convulsions. 

Hyperiemia  of  heart  and  brain. 

Blood,  bright  cherry-red.  Heart   and   lungs  filled  with   dark 

blood. 

The  treatment  must  be  directed,  fii^st,  to  the  immediate  removal  of  the 
patient  from  the  dangerous  atmosphere,  and  secondly,  to  artificial  respiration, 
which  must  often  be  maintained  for  hours.  Friction  of  the  surface,  and 
massage  to  encourage  the  circulation,  and  the  electrical  stimulation  of  the 
phrenic  nerves,  are  rational  proceedings,  the  faradic  currents  being  applied. 
These  are  the  essential  means  to  be  adopted,  which  must  not  be  neglected 
for  efforts  to  administer  any  of  the  hundred  and  one  internal  remedies 
which  have  been  recommended.     In  grave  cases  it  is  also  advisable  to  remove 


OFFENSIVE  BUSINESSES  945 

the  poisoned  blood,  and  introduce  fresh,  blood,  or  better  still,  a  solution  of 
salt  by  transfusion  into  the  veins. 

CAEBON  DIOXIDE  (Caebonio  Acid,  CO,) 

is  a  colourless,  odourless  gas,  with  a  slightly  acid  taste,  and  is  rather  more 
than  one  and  a  half  times  heavier  than  atmospheric  air  (1 : 1-53).  It  exists 
in  air  to  the  extent  of  about  4  per  10,000  volumes.  It  is  also  produced  in 
fermentation,  in  the  burning  of  limestone,  in  deep  wells,  drains,  coal  mines, 
and  other  deep  excavations  (where  it  is  known  as  choke-damp) ;  even  in  grave- 
digging  serious  accidents  have  occurred  ;  and  it  is  evolved  in  great  quantities. 
in  the  artificial  cultivation  of  yeast.  The  gases  developed  in  the  explosion  of 
dynamite  also  contain  CO2  in  large  quantity.  Pure  CO2  is  irrespirable,  causing 
spasmodic  closure  of  the  glottis  ;  when  diluted  with  about  twice  its  volume  of 
air  it  is  respirable.  The  mixture  of  pure  CO2  with  air,  it  must  be  noted,  is 
a  very  different  matter  from  a  mixture  with  air  in  which  the  CO2  has  been 
developed  by  combustion  or  respiration,  which  implies  not  only  production 
of  CO2  but  abstraction  of  oxygen,  every  volume  of  CO2  produced  by  combus- 
tion implying  the  abstraction  of  an  equal  volume  of  oxygen.  In  an  atmo- 
sphere containing  10  per  cent,  of  CO2  developed  by  combustion,  there  will 
be  10  per  cent,  less  oxygen,  not  to  mention  other  modifications  of  the  normal 
constitution  atmosphere. 

The  exact  proportion  which  must  be  present  in  the  air  to  produce  fatal 
effects  is  not  known,  and  no  doubt  is  variable,  being  influenced  by  individual 
circumstances,  as  well  as — above  all  things — by  the  time  during  which  it  is 
inhaled,  and  the  presence  or  absence  of  other  noxious  gases.  No  doubt  a 
smaller  qua,ntity  would  produce  effects  culminating  in  death  if  carbon  dioxide 
were  present  with  other  injurious  gases,  than  if  it  was  mixed  with  pure  air. 
It  may  be  assumed  that  10  to  20  per  cent,  is  a  dangerous  amount. 

Carbon  dioxide  cannot  support  combustion,  and  respiration  and  life  are 
soon  extinguished  where  it  is  present  in  such  proportion  as  that  stated  above. 
That  CO2  is  in  itself  a  poison  and  does  not  produce  toxic  symptoms  merely 
indirectly  by  accumulating  in  the  blood  to  the  exclusion  of  oxygen,  seems 
probable,  though  the  question  is  still  undecided. 

The  more  prominent  symptoms  of  its  absorption  are  headache,  noise  in 
the  ears,  giddiness,  after  which  some  persons  exhibit  excitement,  others  de- 
pression, according  to  individuahty  apparently.  Loss  of  consciousness  and  loss 
of  power  of  movement  are  common  symptoms  in  serious  cases.  The  effects  may 
last  from  a  few  moments  to  two  to  three  days.  There  is  nothing  distinctly 
characteristic  to  be  observed  after  death.  The  diagnosis  can  only  be  esta- 
blished with  any  degree  of  certainty  from  the  history  of  the  case,  which, 
with  the  symptoms,  usually  gives  sufficient  indication  of  the  nature  of  the 
mischief.  The  prognosis  is  less  unfavourable  than  in  poisoning  with  carbonic 
oxide,  and  is  generally  favourable,  except  in  cases  of  acute  poisoning  continued 
for  some  time  ;  in  all  cases  the  individuahty,  duration  of  exposure,  propor- 
tion of  gas  present,  &c.,  form  essential  elements  in  the  prognosis. 

The  treatment  is  the  same  as  for  poisoning  vsdth  carbonic  oxide  except 
as  regards  transfusion.  It  is  very  important  that  any  collection  of  carbonic 
acid  suspected  at  the  bottom  of  wells,  excavations,  &c.,  should  be  thoroughly 
removed  before  men  are  allowed  to  venture  in.  To  effect  this  evacuation  is 
often  a  matter  of  great  difficulty.  Gunpowder  may  be  exploded  at  the 
bottom,  or  limewater  poured  in,  or  baskets  of  hme  suspended  at  the  bottom, 
or  water  in  the  form  of  a  spray  introduced,  or  the  gas  may  be  set  in  move- 
ment by  boughs,  &c.,  being  rapidly  drawn  up  and  down  by  means  of  a  cord. 

VOL.  I.  3  P 


D-IG  HYGIENE 

It  is  commonly  supposed  that  where  a  candle  ■udll  burn  there  cannot  be 
present  a  dangerous  proportion  of  CO^.  But  this  is  not  true.  A  candle  will 
bum  readily  in  air  contaunng  5  to  6  per  cent,  per  volume  of  CO.,,  and  will  still 
continue  to  burn  where  there  is  10  to  12  per  cent.  Even  the  smaller  amoimt 
would  soon  produce  serious  symptoms,  but  the  larger  would  ere  long  cause 
giddiness,  coma,  and  death. 

In  a  room,  &c.,  where  carbonic  oxide  has  been  present  in  a  dangerous 
quantity,  it  is  not  safe  to  trust  in  the  fact  that  a  candle  will  burn  as  an  in- 
dication that  the  danger  has  been  removed,  as  oxycombustion  may  continue 
where  life  will  be  extinguished.  Such  a  place  should  not  be  entered  imtil  it 
has  been  thoroughly  ventilated. 

COAL  GAS 

Coal  gas  is  a  mixture  chiefly  consisting  of  marsh  gas  (CII,!),  hydrogen, 
olefiant  gas  (CoH,,),  carbonic  oxide  (CO),  and  impurities. 

The  following  is  given  as  an  analysis  of  average  coal  gas  when  fairly 
purified : — 

Parkes       Boscoe 
Per  cent. 

Hydrogen— H 40-45-58     47-60 

Marsh  gas  (light  carburetted  hydrogen)  — CH^     .     35-40         41-53 
Olefiant  gas  (heavy  carburetted  hydrogen) — C^H^       3-4  8-05 

Carbon  monoxide— CO 3-6-6  7-82 

Carbon  dioxide— CO. 3-3-72 

Acetylene- CH, .     ' 2-3 

Sulphuretted  hydrogen— ILS       ....       0-29-1 

Nitrogen— N 2-2-5 

Sulphurous  acid— SO. 0-5-1-0 

Ammonia  or  ammonium  sulphide — NHaOr  (NH|)_,S 
Carbon  bisulphide — CS.       ... 

The  carbon  dioxide  may  run  to  double  or  treble  the  amount  here  given, 
or  even  higher,  and  the  marsh  gas  may  be  as  high  as  56  per  cent.,  in  which 
case  the  hydrogen  is  small.  The  statutory  maximum  of  sulphur  allowed 
is  20  grains  per  100  feet,  but  as  much  as  60  grains  has  been  found,  and 
it  is  required  that  there  shall  be  no  sulphuretted  hydrogen  present. 

The  principal  stages  of  the  manufacture  of  gas  are  as  follows.  The 
coal  is  first  distilled  in  large  cast-iron  or  fireclay  retorts,  set  in  brickwork, 
which  hold  2  to  3  cwt.  of  coal  each,  and  are  heated  by  coke  fires  from  with- 
out. The  charge  takes  from  four  to  six  hours  to  distil.  The  result  of  this 
process  is  the  production  of  coke,  which  remains  in  the  retorts,  and  various 
volatile  products,  including  various  gases,  tar,  and  an  ammoniacal  liquor 
termed  gas  liquor.  The  tar  and  liquor  are  condensed  in  tubes  six  to  nine 
inches  in  diameter,  and  are  collected  in  reservoirs  placed  beneath. 

At  this  stage  the  gas  is  very  impure.  Some  of  its  constituents,  ammonia 
and  carbon  dioxide,  are  not  combustible ;  sulphuretted  hydrogen  and  bi- 
sulphide of  carbon  have  a  most  unpleasant  smell  and  produce  irrespirable 
gases  when  burned.  To  effect  the  removal  of  other  impurities  the  gas  is 
passed  through  coke  scrubbers,  where  it  deposits  some  of  the  ammonia, 
with  some  of  the  carbonic  acid  and  sulphuretted  hydrogen  as  carbonate  and 
sulphide  of  ammonia. 

The  most  important  impurity  to  be  got  rid  of  subsequently  is  sulphur,  which 
is  present  in  all  coals,  but  especially  in  inferior  qualities.  The  combustion 
of  sulphur  evolves  SO.2,  the  presence  of  which  is  not  only  dangerous  in  large, 
but  is  unpleasant  even  in  very  small  quantities,  and  is  most  injurious  to  plants, 
and  bleaches  coloured  objects  of  various  kinds,  tarnishes  gilding,  and  almost 


OFFENSIVE  BUSINESSES  947 

all  metal.1.  The  sulphur  which  exists  in  the  gas  at  this  stage,  chiefly  in 
combination  with  hydrogen,  ammonia,  and  compounds  of  carbon  and 
hydrogen,  is  removed  by  treatment  with  lime,  which  also  removes  carbon 
dioxide  and  cyanogen,  which  last  is  generally  present  in  small  quantity. 
As  ammonia  does  not  combine  with  lime,  a  great  quantity  of  this  valuable 
material  may  thus  be  lost.  As  a  purifying  agent,  that  known  as  Laming' s 
was  long  in  great  repute,  but  is  now  not  much  used.  It  consists  of  one  equi- 
valent of  lime  and  one  of  ferrous  chloride,  to  which  chloride  of  calcium 
and  oxide  of  iron  are  subsequently  added.  When  impure  gas  is  brought 
in  contact  with  this,  the  ammonia  and  carbonic  acid  combine  with  the  chlo- 
ride of  calcium  to  form  carbonate  of  calcium  and  chloride  of  ammonium, 
whilst  the  sulphuretted  hydrogen  is  resolved  into  sulphide  of  iron  and 
sulphur  by  the  oxide  of  iron. 

The  process  of  manufacture  varies  somewhat  in  different  manufactories. 
For  instance,  instead  of  the  above,  the  following  stages  and  methods  are 
sometimes  employed  : — 

The  impure  gas  from  the  retorts,  after  condensation  in  upright  tubes, 
is  passed  through  scrubbers  consisting  of  coke,  and  next  through  a  water 
scrubber  in  constant  motion,  where  the  ammonia  is  absorbed  (and  where 
the  valuable  ammoniacal  liquor  originates) ;  the  gas  is  then  passed  through 
three  oxide  of  iron '  purifiers  '  in  succession,  in  order  to  get  rid  of  the  sulphur. 
After  this  it  is  passed  through  lime  to  purify  it  from  carbonic  acid,  being 
passed  thence  to  the  station  meter,  and  from  there  to  the  gasometer. 

The  oxide  of  iron,  after  being  subjected  to  the  action  of  the  impure  gas, 
turns  almost  black  in  colour,  which  occurs  when  it  has  absorbed  some  4  to  6 
per  cent,  of  sulphur.  The  time  required  for  this  will  vary,  of  course,  with 
the  relative  quantity  of  gas  and  oxide.  In  large  well-managed  works,  when 
in  full  activity,  the  quantities  are  so  balanced  that  the  oxide  is  changed 
about  every  three  to  five  days.  It  is  then  taken  out,  spread  on  the  ground, 
and  exposed  to  the  air  to  be  revivified,  being  turned  over  and  over  if  necessary. 
This  process  requires,  under  favourable  circumstances  (good  weather,  abun- 
dant space,  &c.),  some  two  to  four  days.  As  it  becomes  '  revived '  it  gets 
gradually  lighter  in  colour,  turning  to  brown.  It  is  then  returned  to  the 
purifier  for  further  use,  and  after  serving  its  purpose  there  is  again  'revived,' 
and  again  taken  out.  Ultimately,  when  it  has  taken  up  as  much  sulphur 
as  possible,  which  may  reach  50  to  70  per  cent.,  it  is  taken  to  chemical 
works,  and  the  sulphur  it  has  taken  up  is  utilised  for  the  manufacture  of 
sulphuric  acid,  if  that  process  of  utilisation  is  employed. 

The  gas-lime  has  a  strong  and  offensive  smell,  and  is  not  easy  to  dispose 
of.  It  is  unsuitable  as  manure  until  after  long  exposure  to  the  air  ;  and  it 
must  not  be  discharged  into  streams,  nor  buried  in  the  earth,  as  it  would 
soon  pollute  wells  and  streams,  and  its  vapours  may  be  carried  a  long 
way  subterraneously.  Salts  of  iron  are  the  best  means  of  rendermg  it 
harmless. 

Laming's  purifier  becomes  regenerated  by  exposure  to  the  air,  the  iron 
becoming  oxidised  and  the  sulphur  set  free  ;  but  large  airy  sheds  are  required 
for  the  purpose,  and  its  emanation  may  be  very  offensive. 

The  gas  is  conducted  from  the  purifiers  into  the  gasometers,  vast  recep- 
tacles which  are  placed  in  excavations  in  the  earth  reaching  to  a  great 
depth,  and  in  which  water  is  collected  to  seal  the  gasometers  and  prevent 
the  escape  of  gas. 

The  employment  of  gas  involves  important  sanitary  considerations,  which 
are  even  more  important  for  those  who  have  it  introduced  into  their  houses 
for  use  as  an  illuminating  and  heating  agent  than  for  the  makers  of  it ; 

3p2 


9i8  HYGIENE 

indeed,  the  ■workmen,  as  a  rule,  do  not  suffer  much  from  the  specific  product 
they  manufacture. 

Dui-ing  the  removal  of  the  gas-lime  from  the  tank  it  is  liable  to  cause 
considerable  irritation  to  the  nose  and  eyes,  through  the  dust  and  vapours  of 
cyanogen  compounds  and  ammonia  given  off.  The  care  required  to  be 
taken  in  disposing  of  the  gas-lime  has  already  been  referred  to. 

The  construction  of  the  underground  receptacles  of  the  gasometers  re- 
quires to  be  of  the  best  kind  to  prevent  leakage,  and  the  escape  of  the  water, 
charged  as  it  often  is  Avith  tar,  carbolic  acid,  &c.,  by  which  water-supplies, 
&c.,  may  be  rendered  unlit  for  use  entirely,  or  for  very  long  periods.  Some 
of  these  gasometers  are  of  immense  size,  many  holding  over  8,000,000  cubic 
feet  of  gas.  One  to  hold  12,000,000  is  now  beuig  built  at  North  Greenwich, 
and  the  depth  of  the  excavated  bed  may  reach  to  30  to  40  feet. 

It  is  a  matter  of  no  small  importance  that  effective  precautions  be  taken 
to  prevent  either  the  escape  of  gas  from  the  pipes,  as  they  pass  underground, 
or  the  entrance  of  air  into  them  ;  water  getting  into  smaller  pipes  causes 
inconvenience  by  the  flickering  ('bobbmg')  of  the  hght.  Gas  escapmg 
through  the  ground  may  travel  long  distances,  and  enter  dwelling-houses,, 
and  produce  serious  and  even  fatal  effects  ;  it  may  injure  water-supplies,  and 
it  is  very  mjurious  to  trees,  the  roots  of  which  are  exposed  to  its  action ;  they 
soon  shed  their  leaves  and  die. 

Coal  gas  when  mixed  with  air  in  the  proportion  of  1  volume  to  8  to  12  is 
highly  explosive,  but  even  1  volume  to  (3  to  7  is  dangerous. 

The  sanitary  considerations  with  regard  to  coal  gas  by  no  means  terminate 
with  the  completion  of  its  manufacture.  Owing  to  its  constant  presence  in 
the  gas  pipes  wMch  ramify  in  every  direction  through  our  houses,  and  often 
allow  of  escapes  of  gas,  the  most  careful  supervision  is  called  for.  The  escape 
of  a  large  quantity  of  gas  speedily  betrays  itself  by  the  smell,  but  small  quan- 
tities may  be  escaping  continually  without  producmg  any  characteristic 
odoiu',  and  yet  may  cause  very  serious  effects.  Gas  may  lose  its  smell  easily 
enough,  even  when  escaping  in  considerable  quantity,  if  it  has  to  filter  through 
even  a  small  thickness  of  wall,  or  through  the  floor  of  an  ordinary  house, 
where  the  pipe  hes  between  the  floor  of  an  upper  room  and  the  ceihng  of 
that  below.  Of  course  the  deodorisation  will  depend  on  the  quantity,  pres- 
sm-e,  &c.,  and  the  speed  with  which  it  passes  through  the  obstacles.  It  is 
generally  supposed  that  so  little  as  0*5  per  cent,  of  gas  in  the  air  of  a  room 
will  produce  a  readily  detectable  smell.  But  in  a  room  which  is  con- 
stantly occupied,  where  there  is  much  furniture  (which  always  gives  off' 
a  certain  amount  of  odour),  several  gas  lamps  (which  often  have  more  or 
less  smell,  and  a  very  decided  one  if  there  be  an  india-rubber  connection 
with  the  gas),  a  great  deal  more  than  that  proportion  will  not  attract  notice, 
especially  if  the  occupants  of  the  room  be  inured  to  the  presence  of  gas,  and 
are  thus  rendered  to  some  extent  abnormally  defective  in  sensitiveness  of 
smell. 

Among  the  worst  of  the  products  of  combustion  of  coal  gas  are  sulphuric 
acid,  which  may  sometimes  be  tasted  on  the  surface  of  objects  in  a  room  with 
bad  gas  ;  and  carbon  monoxide,  of  which  a  considerable  quantity  is  given  off' 
when  gas  is  only  partially  burned. 

But  it  is  in  bedrooms  that  the  effects  of  escapes  of  gas,  often  trivial  and 
not  noticed,  are  likely  to  be  most  harmful.  During  the  day  and  evening 
people  are  more  or  less  in  movement :  the  doors  are  frequently  opened  and  shut, 
the  room  is  more  or  less  ventilated  by  these  means,  and  perhaps  by  the  fire. 
But  a  person  remains  in  bed  usually  from  six  to  eight  hours,  hi  an  atmosphere 
which  is  scarcely  in  movement,  and  is  very  commonly  hardly  ever  renewed, 
owing  to  the  common  habit  of  keeping  the  bedroom  door  shut ;  the  bed  is 


OFFENSIVE  BUSINESSES  949 

often  intentionally  placed  with  the  head  close  to  the  gas  bracket,  and,  as 
one  goes  to  bed  with  the  intention  of  sleeping,  it  is  not  noticed  whether  some 
drowsiness  may  not  be  attributable  to  a  shght  escape  of  gas  instead  of  to 
natural  causes.  The  writer  knows  of  many  cases  of  chronic  illness  entirely 
due  to  absorption  of  gas  in  this  way,  the  patients  recovering  completely 
when  they  were  removed  to  another  bedroom  where  there  was  no  escape. 
He  was  himself  a  great  sufferer  for  several  weeks,  and  quite  incapacitated 
from  work,  owing  to  an  escape  of  gas  between  the  floor  of  his  bedroom 
and  the  ceiling  of  the  room  beneath.  The  gas  had  quite  lost  its  characteristic 
odour  in  passing  through  the  floor  and  carpet,  although  the  quantity  was  suffi- 
cient to  make  a  large  flame  when  a  light  was  applied  at  the  point  of  escape. 

As  an  illustration  of  the  remarkable  way  in  which  coal  gas  may  be  drawn 
into  a  house  from  an  escape  in  a  main  outside,  the  following  tragical 
history,  investigated  by  the  writer,  is  most  instructive.  It  occurred  in  1682 
in  the  town  of  Glossop.  In  front  of  a  couple  of  cottages  in  the  outskirts 
of  the  town  ran  an  iron  gas-pipe,  two  to  three  inches  in  diameter,  some  eight 
to  ten  inches  under  the  surface  of  the  ground.  This  pipe  had  supplied 
a  mill  beyond  the  cottages ;  but  the  mill  being  disused  at  the  time  of  this 
occurrence,  the  end  of  the  pipe  was  plugged,  but  the  pipe  continued  full 
of  gas.  The  cottages  were  not  supplied  with  gas.  The  pipe  was  about 
three  yards  from  the  front  wall  of  the  houses.  A  woman,  her  two  children, 
and  a  man  lived  in  the  cottage  nearest  the  town.  As  none  of  the  inmates 
of  this  cottage  were  seen  during  the  whole  of  one  day,  and  no  sound  was 
heard,  the  neighbours  (who,  as  the  day  wore  on,  noticed  the  smell  of  gas) 
forced  an  entrance.  On  getting  through  the  front  door  they  were  almost 
suffocated  by  the  smell  of  gas,  and  on  making  their  way  upstairs  they  found 
iilae  man  and  the  two  children  dead,  and  the  woman  in  her  last  moments. 
It  was  found  that  the  gas-pipe  was  broken  (probably  by  a  cart  which 
delivered  a  load  of  coal  at  the  house  on  the  previous  evening)  underground 
about  five  yards  from  the  dwelling-house.  An  outhouse  built  in  connection 
with  the  house  intervened  between  the  broken  pipe  and  the  house.  The  gas, 
therefore,  had  traversed  all  this  extent  of  earth,  had  passed  through  the 
foundation  wall,  and,  having  first  narcotised  the  mifortunate  victims,  ulti- 
mately killed  them. 

It  is  a  most  remarkable  fact  that,  the  pipe  being  laid  close  to  the 
surface,  the  gas  did  not  all  escape  above  ground  instead  of  travelling  so 
far  underground  into  the  house,  the  surface  being  only  ordinary  earth, 
hardened  by  traffic  of  feet  only.  There  was  only  one  fireplace  in  the  house, 
and  that  downstairs  ;  in  the  room  upstairs,  where  the  victims  lay,  there  was 
none.  This  aspiration  can  only  be  attributed  to  the  warmth  of  the  house. 
The  outside  air  and  earth  would  not  be  very  cold,  as  it  was  in  summer. 

It  is,  of  course,  possible  that  the  gas  may  first  have  entered  the  out- 
house and  penetrated  from  thence  into  the  dwellmg  house,  but  it  seems 
improbable,  as  there  was  no  accumulation  of  gas  noticed  in  it. 

Biefel  and  Poleck  give  the  following  analyses  of  coal  gas,  before  and  after 
passage  through  a  layer  of  sandy-humus  earth  two  metres  thick  (=  78-7  in.) : 

Before  After 
passing  through  the  2  metres  of  earth 

Carbonic  oxide— CO 10-52  13-93 

Carbon  dioxide— COj          ....       3-06  2-23 

Heavy  carburetted  hydrogen — C.^H^  .         .       4-66  0-69 

Light  carburetted  hydrogen — CH^     .        .     31-24  17-76 

Hydrogen— H 49-44  47-13 

Oxygen— 0 0-0  6-55 

Nitrogen— N 1-Q8  1171 

myoo  100^ 


050  HYGIENE 


IODINE 


Dried  sea-weed  is  collected  iu  piles  on  the  shore  and  hurned,  leaving  an 
impure  ash  known  as  kelp,  which  contains  iodine.  Suhsequently  the  iodine  is 
obtained  pure  by  heating  with  sulpliuric  acid  and  manganese  dioxide  and 
afterwards  subliming.  It  gives  off  a  perceptible  vapour  at  the  ordinary  tem- 
perature. Considerable  quantities  of  metallic  compounds  of  iodine  are  found 
in  the  preparation  of  nitrate  of  potassium  from  Chili  nitrate. 

In  Germany  iodine  is  chietiy  got  from  the  iodide  by  distillation  with 
concentrated  sulphuric  acid  and  nitrate  of  potassium. 

Iodine  acta  as  a  caustic  on  the  skin.  The  vapour  when  inhaled  in  any 
quantity  produces  irritation  of  the  respiratory  passages,  coryza,  sneezuig, 
frontal  headache,  and  even  temporary  unconsciousness.  Prolonged  exposure 
to  its  action  causes  a  characteristic  coryza,  with  exaggeration  and  persistence 
of  the  symptoms  which  are  observed  in  temporary  attacks. 

The  distillation  and  subsequent  sublimation  of  the  iodine  are  the  stages 
at  which  the  vapours  are  likely  to  be  most  dangerous,  and  the  essential  pre- 
cautions are  to  have  the  vessels  made  thoroughly  air-tight,  so  as  to  secure  the 
cooling  and  condensation  of  the  iodine  without  escape  of  the  vapour.  When 
the  iodine  is  being  removed  from  the  receptacles  it  is  also  liable  to  affect  the 
workpeople.  In  addition  to  other  precautions  it  is  then  necessary  to  be 
careful  about  the  local  action  of  iodine  on  the  skin,  especially  if  this  be  broken. 
"When  sulphuric  acid  is  added  to  the  kelp,  in  the  early  stage  of  the  manufac- 
ture, large  volumes  of  sulphuretted  hydrogen  are  set  free  which  should 
be  drawn  into  the  chimney,  if  the  process  is  carried  on  in  a  factory,  and 
not  in  the  open  air. 

BEOMINE 

Bromine  is  found  as  bromides  in  many  mineral  springs,  in  sea  water,  and 
in  the  ash  of  marine  animals  and  plants  (kelp).  The  mother  liquor  obtained 
by  evaporation,  or  by  treatment  of  kelp,  &c.,  is  distilled  in  stone  vessels  with 
manganese  dioxide  and  sulphuric  acid.  The  bromine  evolved  is  condensed 
in  a  leaden  or  earthenware  tube,  and  collected  in  bottles. 

The  impure  bromine  is  purified  by  fractional  distillation.  It  is  kept 
in  bottles  with  well-ground  stoppers,  fixed  with  varnish,  clay,  and  linen  or 
parchment  paper.  In  consequence  of  its  dangerous  properties,  and  the 
consequent  expense  of  transport,  bromide  of  iron  is  often  used  for  transport 
instead  of  bromine,  for  the  preparation  of  the  various  salts  in  use,  of  which 
enormous  quantities  are  now  used  in  medicine. 

Bromine  is  a  dark,  reddish  black,  heavy  liquid.  It  has  a  strong, 
pecuUar,  irritating  smeU,  and  acts  as  a  strong  poison  when  inhaled.  It 
affects  the  workpeople  very  much  like  iodine.  It  causes  irritation  of  the 
mucous  membrane,  increased  flow  of  saliva  and  tears,  cough,  malaise,  giddi- 
ness, spasm  of  the  glottis,  and  asphyxia.  Immediate  removal  from  the  place 
and  inhalation  of  aqueous  vapour  are  recommended  as  the  best  remedies. 
Free  ventilation  to  prevent  the  accumulation  of  the  poisonous  vapours  is  very 
important. 

The  most  dangerous  stages  of  the  manufacture  are  when  the  stone 
receptacles  are  bemg  emptied.  In  the  emptying  of  the  vessels  used  for 
rectifying  the  bromine,  also,  the  workmen  are  much  exposed  to  danger, 
and  must  protect  mouth  and  nose  with  cloths.  Again,  when  the  bromine  is 
being  filled  into  the  bottles  for  storage,  it  is  absolutely  necessary  for  the  men 
to  protect   their  respiratory  organs  by  the  use  of  cloths,  cotton   wool,  &c.- 


OFFENSIVE  BUSINESSES  951 

Sometimes  a  condition  much  resembling  bronchial  asthma  occurs  to  work- 
men, but  specific  chronic  intoxication  is  unknown. 

It  is  essential  that  only  healthy  workmen  should  be  employed  in  this  trade. 
Those  with  any  predisposition  to  pulmonary  disease  or  to  excess  in  drink  should 
be  rigidly  excluded.  If  this  be  done,  and  the  precautions  referred  to  observed, 
the  health  of  the  workpeople  seems  not  to  be  injuriously  affected. 

The  passage  of  water  containing  bromine  from  the  works  into  neighbour- 
ing streams  and  water-supplies  must  be  most  carefully  prevented  ;  the  vege- 
tation of  the  neighbourhood  will  certainly  be  destroyed  if  the  vapours  are 
allowed  to  escape  unchecked. 

CIILORINE 

The  effects  of  chlorine  and  hypochlorous  acid  are  somewhat  similar  to 
those  of  iodine  and  bromine,  and  are  frequently  seen  in  workers  where 
chlorinated  lime  ('  bleach  ')  is  used,  as  in  the  manufacture  of  this  compound, 
bleach  works,  &c. 

Chlorine  when  inhaled  in  a  concentrated  form  causes  spasm  of  the  glottis  ; 
when  more  dilute,  irritation  of  the  bronchial  passages,  eyes,  nose,  and  throat. 
Men,  however,  soon  became  habituated  to  the  inhalation  of  dilute  chlorine, 
though  they  suffer  from  dyspepsia  and  acidity  of  the  stomach,  and  lose  flesh 
and  become  anfemic.  Loss  of  smell  is  a  common  chlorine  symptom  among 
workers  in  chlorine. 

ARSENIC 

This  metal  sometimes  occurs  free  in  nature,  but  is  more  commonly  found 
in  combination  as  an  alloy,  especially  with  iron,  cobalt,  and  nickel.  It 
is  widely  distributed,  and  is  a  not  uncommon  constituent  of  mineral  springs. 

It  is  generally  recovered  from  its  ores  by  roasting,  or  by  being  exposed  to 
a  current  of  heated  air  in  a  reverberatory  furnace,  arsenious  acid  (AsjOg)  being 
formed.  This  is  carried  off  as  a  vapour  into  long  flues,  where  it  is  preci- 
pitated as  '  white  arsenic,'  or  arsenious  acid. 

Metallic  arsenic  is  little  used,  except  in  the  manufacture  of  shot  to 
impart  hardness.  It  also  exists  in  '  white  copper,'  or  '  new  silver,'  an  aUoy 
of  copper  and  zinc. 

The  emptying  of  the  flues  or  chambers  in  which  the  arsenious  acid  has 
condensed  is  a  very  dangerous  operation  for  the  workmen.  They  are  gene- 
rally cased  in  leather,  glazed  eye-holes  being  left  to  enable  them  to  see,  the 
mouth  and  nose  being  covered  with  damp  cloth. 

Combined  with  copper  it  constitutes  the  brilliant  Scheele's  green,  and 
another  much  used  pigment,  the  Schweinfurth  green,  is  a  double  salt  of 
arsenite  and  acetate  of  copper.  These  are  the  only  metallic  arsenites  used 
in  the  industries.  They  are  found  in  wall  papers,  green  water-colour  paints, 
oil  paints,  wafers,  &c.,  and  have  caused  fatal  effects  from  being  inadvertently 
used  to  colour  blanc-mange  and  confectionery.  The  makers  of  the  arsenical 
green  wall  paper,  printers  using  green  pigment,  and  occupants  of  rooms 
papered  with  this  deadly  substance  have  suffered  serious  illness  and  even 
died  from  its  effects.  It  is  also  used  in  preparing  anunal  skins  for  stuffing. 
Schweinfurth  green  is  used  for  colouring  carpets,  artificial  flowers,  light 
tarlatan  for  dresses,  green  paper  lamp-shades,  &c.  The  grinding  of  Schwein- 
furth green  is  a  most  dangerous  process,  and  yet  it  is  very  remarkable 
that  the  men  suffer  so  little,  seeing  that  they  are  covered  with  the  dust  from 
head  to  foot. 

In  the  preparation  of  artificial  flowers  (leaves,  buds,  twigs,  &c.)  the  greea 


952  HYGIENE 

colour  is  obtained  from  the  same  source.  The  leaves  are  cut  out  of  paper, 
cloth,  &c.,  which  is  usually  dyed  beforehand  with  a  colour  of  the  same  cha- 
racter, then  they  are  usually  varnished  and  the  powdered  Schweinfurth  green 
sprinkled  on.  This  is  a  most  dangerous  operation,  leading  to  inflammation 
of  the  eyes,  swelhng  of  the  face,  and  ulceration  of  the  hands.  The  use  of 
the  dry  powder  should  be  entirely  forbidden,  and  the  colour  should  be  used 
only  when  mixed  with  collodion,  turpentine,  &c. 

Arsenite  of  potassium  is  an  important  compound,  as  it  is  used  for  the 
manufacture  of  Scheele's  green,  which  is  an  arsenite  of  copper.  It  is  pro- 
duced by  acting  on  a  solution  of  sulphate  of  copper  with  arsenite  of  potassium, 
or  by  dissolving  in  water  arsenious  acid  or  adding  sulphate  of  copper,  and 
then  precipitatiiig  with  an  alkaline  carbonate. 

Ai'seniate  of  sodium  is  also  of  importance,  because  in  its  manufacture,  as 
in  that  of  arsenic  acid,  abundant  and  highly  dangerous  nitrous  vapours  are 
discharged. 

Arsenic  acid  is  largely  used  in  various  industries,  especially  in  the  manu- 
facture of  certain  aniline  colours  such  as  magenta  and  rosaniline.  Arseni- 
ous acid  has  been  found,  and  arsenic  acid  been  found  to  the  extent  of  7  per 
cent,  in  such  colours.  These  brilhant  colours  are  largely  used  to  render 
more  attractive  syrups,  sweetmeats,  Mqueurs,  &c.  It  has  been  supposed  that 
the  bad  efl'ects  sometimes  attributed  to  the  wearing  of  flannel,  socks,  &c., 
dyed  with  aniline  colours  may  really  have  been  due  to  arsenic  present  in 
some  form. 

Orpiment,  or  yellow  tersulphide  of  arsenic,  owes  its  dangerous  properties 
to  the  presence  of  arsenious  acid.  It  is  sometimes  found  native.  It  is  the 
chief  ingredient  in  King's  yellow,  which  is  a  mixture  of  orpiment  and 
arsenious  acid.  It  is  much  used  in  paper-staining,  painting,  dyeing,  and 
colouring  toys.  It  has  been  used  (instead  of  lead  chromate)  to  colour  Bath 
buns.  It  is  also  used  in  fellmongering,  mixed  with  lime,  in  the  removal  of 
wool  from  the  hides. 

Absorption  of  the  poison  may  take  place  through  a  raw  surface,  and 
even  through  the  unwounded  skin.  It  is  not  an  accumulative  poison,  but  is 
ehminated  by  the  urine,  sweat,  and  bile.  It  causes  paralysis  of  the  heart, 
but  whether  directly  or  indirectly  is  uncertain. 

The  conditions  of  chronic  poisoning  may  ensue  from  one  large  dose,  or 
from  repeated  small  doses.  Gastric  catarrh  is  the  prominent  symptom  at  first, 
accompanied  by  the  pecuhar  feeling  of  burning  in  the  fauces,  dry  tongue, 
thirst,  and  sometimes  superficial  ulceration  in  the  mouth.  There  is  irri- 
tation of  the  conjunctivae,  with  sufiusion  of  the  eyes,  and  more  or  less 
photophobia.  The  skin  often  exhibits  a  pecuhar  vesicular  eruption,  called 
eczema  arsenicale,  or  the  eruption  may  resemble  the  nettle-rash  form  of  scar- 
latinal rash.  There  may  be  well-marked  nervous  symptoms,  even  including 
paralysis. 

Notwithstanding  these  severe  symptoms  of  general  intoxication  patients 
have  been  known  to  recover  completely,  after  two  to  three  weeks,  if  placed 
Tinder  proper  treatment. 

It  is  absolutely  necessary  to  remove  from  the  influence  of  the  poison 
persons  who  show  symptoms  of  being  affected,  and  this  whether  they  are 
suffering  from  symptoms  of  general  intoxication,  or  merely  from  skin  or 
other  external  affection.  It  is  by  no  means  certain  that  the  skin  affections 
are  not  sometimes  indicative  of  antecedent  general  affection,  and  not  merely 
a  preliminary  and  localised  result  of  the  action  of  arsenic. 

The  personal  hygiene  of  the  workmen  should  be  directed  to  the  mainte- 
nance of  great  personal  cleanhness,  avoidance  of  exposure  of  any  wounded 


OFFENSIVE  BUSINESSES  953 

•surface  of  skin  to  the  action  of  dust  or  vapour  containing  arsenic,  avoidance 
of  taking  any  food  or  drink  in  the  workrooms,  regularly  changing  the  work- 
ing clothes  before  going  home,  shaving  the  face  clean  and  keeping  the  hair 
short  to  avoid  accumulation  of  dust,  &c. 

The  preventive  hygiene  consists  partly  in  the  provision  of  suitable  con- 
densing chambers,  and  especially  their  complete  closure,  and  partly  in  efficient 
ventilation. 

Public  hygiene  demands  the  absolute  prevention  of  any  water  containing 
arsenic  being  discharged  into  sewers  or  streams.  The  chimneys  should  also 
■be  of  considerable  height,  and  from  time  to  time  the  vapours  should  be 
■examined  to  see  that  no  arsenic  is  escaping.  The  insertion  of  numerous 
projecting  buttresses  in  the  condensing  flues  is  a  successful  method  of  in- 
creasing their  power  of  securing  the  maximum  of  condensation. 

One  of  the  most  important  of  the  measures  of  precaution  is  the  employ- 
ment of  arsenical  colours  as  little  as  possible,  and  it  is  greatly  to  be  desired 
that  chemists  would  direct  their  attention  to  enabling  this  to  be  done  suc- 
-cessfully.  There  can  be  little  doubt  that  all  the  advantages  of  the  highly 
dangerous  arsenical  greens  could  be  obtained  without  their  dangerous  pro- 
perties, if  the  question  were  seriously  taken  in  hand  and  an  effort  made  to 
;release  the  makers  and  men  from  the  danger  they  involve. 

CHKOMIUM 

Although  this  metal  is  scantily  distributed  in  nature,  its  compomids  are 
;  greatly  used  in  certain  industries,  and  have  a  great  sanitary  importance  from 
their  dangerous  action.    The  principal  ore  of  chromium  is  chrome  ironstone. 

Its  most  important  salts  for  iadustrial  purposes  are  the  bichromate 
(K2Cr207),  which  is  prepared  by  fusing  a  chromic  compound  with  potassium 
■carbonate,  when  it  becomes  oxidised  and  a  yellow  soluble  chromate  is 
formed.  By  the  addition  of  sulphuric  acid  the  bichromate  is  formed,  in  red 
crystals.  This  salt  is  the  great  source  of  the  valuable  chrome  pigments,  and 
is  used  by  both  the  calico  dyer  and  cahco  printer  to  produce  the  chromates  of 
lead  (chrome  yellow  and  orange  red).  It  is  also  used  in  mordanting  wool  and 
in  the  dyeing  of  silk  and  linen.  Chrome  colours  are  also  largely  used  in 
glass  and  porcelain  painting. 

It  is  equally  important  to  the  dyer  as  a  powerful  oxidising  agent,  this 
property  being  sometimes  utihsed  to  develop  colour,  and  sometimes,  on  the 
contrary,  to  destroy  it. 

Chromates  of  barium,  lead,  and  copper,  and  a  dichromate  of  sodium,  chrome 
alum,  chromium  sulphate  and  acetate,  and  several  other  compounds,  of 
which  the  nitrate,  sulphate  and  nitrate-acetate,  and  acetate  are  the  most 
important,  are  much  used  in  calico-printing  for  steam-colours — e.g.  browns, 
blacks,  olives,  &c. 

Poisoning  from  swallowing  of  bichromate  of  potash  has  occurred,  the 
principal  symptoms  resembling  those  of  Asiatic  cholera  very  closely  :  about 
half  a  grain  has  been  known  to  produce  poisonous  effects,  with  vomiting, 
and  profuse  diarrhoea.  The  symptoms  are  not  unlike  those  of  poisoning  with 
arsenic  or  mercury.  Sometimes,  however,  the  nervous  system  alone  seems 
affected,  and  not  the  digestive  tract.  Poisoning  has  been  caused  by  the 
use  of  chromate  of  lead  instead  of  turmeric  for  staining  the  skins  of  sausages. 

Chrome  yellow  is  frequently  used  to  colour  papers  for  wrapping  bonbons 
.  in  ;  it  is  more  likely  to  be  dangerous  in  the  form  of  paint  in  children's  paint- 
boxes, and  has  more  than  once  caused  death  when  employed  to  colour 
:  sweets  in  quantities  so  small  as  a  fifth  of  a  grain. 


054  HYGIENE 

The  action  of  the  chromates  and  bichromate  of  potash  on  the  skin  and 
nerves  causes  destructive  ulcerative  action  on  the  skin  and  mucous  membranes, 
unfortunately  too  well  known.  It  has  been  said  that  a,  man  who  worked 
at  bichromate  could  be  recognised  at  a  glance  by  the  deformity  of  his  nose. 

The  pulverising  of  the  chrome-u-on  ore  does  not  appear  to  produce  the 
almost  specific  injuries  of  chrome,  and  is  offensive  only  as  a  dust,  which,  like 
others,  is  injurious  when  constantly  inhaled. 

Danger  arises  when  the  chromates  are  being  ground.  The  fine  dust  falls 
on  the  skin  and  adheres  to  moist  parts,  which  it  irritates,  acting  with  greatest 
severity  on  the  delicate  mucous  membrane  of  the  nose,  where  the  carelessness 
of  the  workmen  often  leaves  the  dust  undisturbed.  There  is  often  a  quantity 
of  caustic  alkali  mixed  with  the  chromate,  which  increases  the  effect  of  the 
latter.  The  inhaled  dust  causes  sneezing,  and  a  thickish  \Yatery  or  bloody 
discharge  from  the  nose.  Ulcers  form  on  the  septum,  and  not  inh-equently 
end  in  perforation,  which  is  most  commonly  preceded  by  the  formation  of 
a  scab.  There  is  seldom  any  offensive  odour  from  the  ulcers.  On  the 
skin  also  the  vesicles  or  papules  caused  at  first  by  the  irritation  may  end 
in  ulcers  having  clean-cut  edges,  and  appearing  as  if  punched  out.  They 
may  extend  over  a  large  part  of  the  body,  and  destroy  the  tissues  to  the  bone 
if  neglected.  It  is  said  that  snuff"- takers  enjoy  immunity  from  these  effects. 
The  operation  of  pulverising  the  bichromate  and  other  dangerous  salts 
should  be  done  in  a  closed  chamber,  and  should  be  effected  by  rollers.  (Cf. 
Sanitary  Precautions,  art.  Lead,  p.  9C4). 

The  chimney  of  the  calcining  ovens  must  be  furnished  with  proper  means 
of  drawing  off"  the  dust  and  fumes  into  a  suitable  chamber,  to  prevent  destruc- 
tion of  the  vegetation  around,  and  injury  to  men  and  animals.  There  is  also 
danger  of  ponds  and  rain  water  being  poisoned.  It  is  most  important  that 
wash  water,  &c.,  which  may  contain  bichromate,  be  not  discharged  into 
streams  or  ponds  used  for  drinking.  So  dangerous  is  this  process  that  it 
should  not  be  tolerated  in  thickly  populated  neighbourhoods. 

MEECUEY 

This  important  article  of  commerce  is  found  native  in  but  small  quan- 
tities, and  is  chiefly  met  with  as  the  sulphide  or  cinnabar  (vermilion),  some- 
times calomel  or  subchloride.  It  is  the  only  metal  which  is  hquid  at  the  ordi- 
nary temperature,  and  is  so  volatile  that  it  gives  off  vapour  at  all  temperatures. 

The  metal  may  be  extracted  from  the  native  cinnabar  by  burning  off 
the  sulphur,  or  by  heating  the  ore  with  some  substance  which  will  combine 
with  the  sulphur,  and  form  a  fixed  compound  with  it,  thus  aUowuig  the  mer- 
cury to  be  separated  by  heat.  The  former  method  is  practised  at  Almeida,  but 
owing  to  defective  condensation  is  extravagant.  The  latter  method  is  effected 
by  mixing  the  cinnabar  with  iron  fihngs  or  slacked  lime,  and  distilhng  in  re- 
torts. The  sulphur  of  the  cinnabar  combines  with  the  iron  or  hme,  and  the 
mercury  is  vaporised  and  condensed  in  receivers  filled  with  water. 

Mercury  is  used  in  great  quantities  in  extracting  gold  and  silver  from 
their  ores  by  amalgamation,  and  these  amalgams  are  largely  used  in  silvering 
and  gilding.  It  is  also  used  largely  for  silvering  mirrors,  for  the  preparation 
of  vermihon  (ciimabarj,  a  most  important  and  durable  pigment;  as  well  as 
in  the  construction  of  philosophical  instruments,  and  as  a  medicine.  Cinnabar 
is  very  largely  used  as  a  pigment. 

The  perchloride  (corrosive  sublimate,  mercuric  chloride,  HgCl2)  has  come 
into  great  use  of  recent  years  as  a  disinfectant.  It  exercises  a  most  destructive 
action  on  micro-organisms.     A  solution  of  1  per  1,000  is  sufficiently  strong 


OFFENSIVE  BUSINESSES  955 

for  almost  any  purpose  of  this  kind.     Mercurial  poisoning  has  followed  the 
use  of  such  solutions  as  this. 

Mercurous  chloride  (calomel)  is  usually  prepared  by  heating  finely  divided 
metalhc  mercury  with  corrosive  sublimate. 

Among  the  trades  in  which  mercury  or  its  preparations  are  used,  and  in 
which  danger  arises  to  the  workpeople,  may  be  mentioned  the  following  : — 

Bronzing  :  not  infrequently  plaster  objects  are  given  a  metallic  appearance 
by  rubbing  them  with  an  amalgam  consisting  of  equal  parts  of  mercury,  tin, 
and  bismuth,  and  subsequently  varnishing  them.  Persons  engaged  at  this 
work  not  infrequently  exhibit  the  symptoms  of  mercurial  poisoning  in  a  very 
intense  degree. 

Hat-maldng  is  a  trade  of  a  still  more  dangerous  character.  In  the  pre- 
paration of  the  skins  it  is  a  common  practice  to  rub  them  with  a  coarse  brush, 
wet  with  a  10  to  11  per  cent,  solution  of  acid  nitrate  of  mercury  in  nitric  acid. 

In  the  subsequent  operations  of  depilation  and  shaking  the  skins,  clouds 
of  mercurial  dust,  as  well  as  that  of  arsenic,  are  spread  about,  to  the  great 
danger  of  the  workpeople,  among  whom  poisoning  with  both  these  metals  is 
common. 

Gilding  by  the  aid  of  mercurial  gold  amalgam  is  also  a  dangerous  occupa- 
tion, the  workpeople  being  liable  to  intoxication  at  various  stages,  chiefly  in 
the  preparation  of  the  amalgam,  and  in  its  application  to  the  objects  to  be  gilded. 
Mercurial  vapours  are  developed  in  the  bath,  and  also  when  the  mercury  is 
volatilised  at  the  moment  of  applying  the  gilding ;  further,  the  continued 
handling  of  the  mercurial  amalgam  itself  leads  to  cutaneous  absorption  and 
intoxication. 

The  emaciated,  unhealthy  appearance  of  the  workmen  too  commonly 
indicates  the  nature  of  their  occupation.  Closer  examination  shows  their 
irritated  gums,  often  toothless,  and  the  existence  of  skin  irritation,  dyspnoea, 
and  other  disorders  arising  from  exposure,  not  only  to  the  dangerous  action 
of  mercury,  but  also  to  the  nitrous  fumes,  which  are  so  disastrous  to  those 
engaged  in  this  trade. 

Artificial  flower-makers  are  exposed  not  only  to  dangers  from  the  use  of 
poisonous  arsenical  and  lead  colours,  but  are  obliged  also  to  use  the  no  less 
dangerous  mercurial  pigments,  chiefly  the  sulphide,  chromate,  and  biniodide 
(brilliant  scarlet). 

The  operations  of  preserving  and  stuffing  the  skins  of  animals  is  dangerous 
to  those  employed,  from  the  fact  that  arsenic  (generally  in  the  form  of 
soap)  and  corrosive  sublimate  are  largely  employed  by  them.  It  is  not  merely 
at  the  times  when  the  preservative  materials  are  employed  that  the  danger 
exists,  but  long  afterwards  ;  when  these  materials  have  become  desiccated 
they  are  converted  into  dust,  which  permeates  the  atmosphere  of  the  rooms 
where  the  stuffed  animals  are  kept,  and  may  cause  aU  the  symptoms  of 
arsenical  or  mercurial  poisoning. 

Photographers,  who  employ  the  bichloride,  are  also  Kable  to  absorption  of 
the  poison,  especially  if  there  should  be  any  fissures  or  wounds  on  the  hands. 
The  large  amount  of  mercury  employed  in  telegraph  offices,  where  the  wire 
connections  are  often  made  by  means  of  cups  filled  with  mercury  ;  the  enor- 
mous area  of  zinc  plates  which  have  to  be  kept  amalgamated  with  mercury 
at  large  telegraph  stations  ;  the  risks  connected  with  the  preparation  of 
barometers  and  thermometers,  from  which  the  boiling  mercury  sometimes 
escapes,  suggest  important  points  for  sanitary  supervision. 

The  liability  to  mercurial  poisoning  is  all  the  greater,  as  it  is  a  metal  which 
can  undoubtedly  be  absorbed  through  the  unbroken  sMn.  This  fact  is  fami- 
liar from  the  readiness  with  which  toxic  effects  are  produced  by  inunction  of 


956  HYGIENE 

mercurial  ointment  in  medical  practice.  It  may  also  be  absorbed  through 
the  lungs,  whether  it  enter  in  the  form  of  vapour  or  dust,  as  well  as  fi-om 
the  digestive  tract. 

The  absorbed  mercury  probably  exists  chemically  combined  chiefly  with 
albumen  ;  but,  as  it  may  be  excreted  with  urine  free  from  albumen,  it  is 
manifest  that  the  albuminous  compounds  may  again  undergo  decomposition. 
Mercury  is  excreted  not  only  by  the  Iddneys,  but  also  in  the  bile,  milk,  fsces, 
and  probably  in  the  sweat. 

It  is  remarkable  that  mercury  may  exist  in  a  latent  form  in  the  body,  and 
under  favourable  conditions  become  active  and  produce  serious  symptoms  in 
persons  who  had  for  years  been  apparently  free  from  its  influence. 

The  predisposition  to  mercurialism  varies  greatly  in  diflerent  persons,  of 
which  Alfinger  observed  an  illustration  in  the  case  of  the  sister  of  a  woman 
engaged  in  '  silvering  '  mirrors,  who,  although  she  had  never  been  in  the 
factory,  became  afi'ected  with  mercurial  stomatitis  through  contact  with  her 
sister,  who  was  engaged  in  the  mercurial  work,  but  who  was  not  herself  in 
any  way  troubled.  The  injurious  eflects  are  usually  observed  withm  a  few 
weeks  or  months  after  exposure,  while  some  persons  will  escape  for  months, 
or  even  years. 

The  earliest  symptoms  are  nearly  always  increased  secretion  of  saliva 
and  irritation  of  the  mucous  membrane  of  the  mouth,  accompanied  soon  by 
a  peculiar  metalhc  taste.  Inflammation  of  the  gums  soon  follows :  they 
become,  swollen,  tender  and  disposed  to  bleed,  and  the  breath  becomes  most 
offensive.  The  morbid  condition  soon  spreads  over  the  cheeks,  lips,  and 
tongue,  and  they  become  covered  with  a  greyish,  croup-like  membrane.  At 
points  where  the  teeth  press,  ulcers  are  commonly  observed,  which  may  extend 
in  depth  and  area,  and  lead  to  extensive  destruction  of  tissue.  The  general 
nealth  is  always  involved  at  this  stage,  and  there  are  fever  and  restlessness, 
with  gastric  and  intestinal  derangement.  In  some  cases  the  nervous  phe- 
nomena precede  and  are  much  more  serious  than  the  local.  The  patient 
suffers  from  great  anxiety,  the  least  thing  unnerves  him,  and  he  may  have 
hallucinations.  He  cannot  eat,  suffers  from  considerable  salivation,  and 
loses  flesh  rapidly. 

The  gravity  of  these  cases  often  leads  to  long  iUness,  lasting  four  to  six 
weeks,  and  may  even  lead  to  chronic  mercurialism  lasting  for  years ;  but 
they  seldom  end  fatally.  The  inflammation  of  the  mouth,  where  the  general 
health  has  not  suffered  much,  is  usually  subdued  in  a  few  days. 

If  these  symptoms  be  disregarded,  and  the  patient  be  not  at  once  removed 
from  exposm-e  and  put  under  proper  treatment,  there  are  superadded  other 
more  serious  troubles.  There  comes  on  gradually  a  trembling  of  the  muscles, 
commonly  known  as  '  the  trembles  '  (mercurial  tremor),  affecting  gradually  a 
larger  and  larger  area  of  the  voluntary  muscles,  until  finally  the  patient 
may  be  deprived,  not  only  of  the  power  of  locomotion,  but  his  speech  becomes 
stammering  and  hesitating  (psellismus  mercurialis),  and  he  may  be  quite 
unable  to  feed  himself.  The  '  trembles  '  commence  usually  in  the  face  and 
tongue,  and  gradually  extend  to  the  arms  and  legs.  At  first  the  muscles 
are  only  affected  temporarily,  mostly  during  movement  or  under  emotion,  and 
the  tremor  may  cease  entirely  during  sleep.  Eeflex  action  and  power  over  the 
sphincters  and  electrical  irritabihty  continue  unimpaired.  These  symptoms 
may  progress  and  be  rendered  more  serious  by  the  occurrence  of  mental  de- 
rangement, which  sometimes  takes  the  form  of  maniacal  excitement,  but 
more  usually  of  hypochondria. 

The  prognosis  is  in  general  favourable,  but  sometimes  the  tremor  is  never 
lost. 


OFFENSIVE  BUSINESSES  957 

Complete  removal  from  risk  of  further  absorption,  good  food  and  air  com- 
bined with  ferruginous  tonics,  are  the  best  treament.  Chlorate  of  potash  is 
very  useful  for  the  stomatitis.  Small  doses  of  iodide  of  potash  no  doubt  in- 
crease elimination.  Large  doses  have  been  known  to  increase  the  severity  of 
the  symptoms,  apparently  by  setting  free  mercury  fixed  in  the  tissues,  and 
thus  leading  to  its  entrance  into  the  blood  and  nervous  tissues. 

Sanitary  Precautions. — In  this  as  in  other  dangerous  trades  it  is  above 
all  things  important  to  instruct  the  workmen  thoroughly  in  the  nature  of 
the  risks  they  have  to  incur,  and  the  means  of  avoiding  them.  The  protec- 
tion of  the  workman  from  the  local  and  general  affections  arising  from  the 
absorption  of  mercury  into  the  body,  or  from  its  local  action,  requires  a 
combination  of  precautions  on  the  part  of  the  manufacturer  in  the  construction 
and  maintenance  of  his  works,  and  on  the  part  of  the  workman  in  seeing 
that  the  various  means  provided  for  protecting  him  are  kept  in  good  working 
order,  as  well  as  in  taking  great  care  to  supplement  these  precautions  by 
attention  to  personal  hygiene. 

In  the  removal  of  the  contents  of  the  condensing  chambers  and  flues  the 
greatest  care  is  required,  and  these  must  be  constructed  so  as  to  prevent  the 
escape  of  fumes  or  gases.  The  men  should  be  provided  with  long  overalls 
accurately  fitting  at  the  neck  and  wrists,  so  as  to  keep  the  skin  as  well  pro- 
tected as  possible,  and  the  hair  of  the  head  and  face  should  be  kept  close  cut, 
and  a  cap  of  paper  or  other  smooth  material  always  worn,  to  prevent  deposi- 
tion of  dust  in  them,  A  good  mask  would  be  a  great  boon,  but  is  still  a  deside- 
ratum. The  clothes  used  in  the  works  should  not  be  worn  at  home,  but  left 
at  the  workshop.  Great  cleanliness  should  be  maintained  by  frequent  wash- 
ing, especially  of  the  hands,  face,  and  mouth  ;  and.  means  for  this  should  be 
conveniently  placed  for  the  workmen,  as  well  as  warm  baths,  in  which  their 
whole  body  can  be  thoroughly  freed  from  the  noxious  materials.  The 
chambers  where  mirrors  are  '  silvered  '  require  to  be  well  ventilated,  and 
the  ventilation  should  be  downwards,  as  the  vapours  are  heavy  and  rise  but 
slowly  from  the  m.ercury  bath,  and  all  the  workrooms  must  be  freed  from 
deposits  of  dust  at  very  short  intervals.  In  spreading  the  mercury  on  the 
glass  it  is  most  important  that  the  hand  be  not  directly  placed  in  the  metal ; 
the  flannel  with  which  the  spreading  is  usually  done  should  be  held  by  a 
rod,  so  as  to  keep  the  workman  as  far  as  possible  from  the  fumes.  The 
mercury  should  be  kept  in  covered  vessels  as  much  as  possible,  to  prevent 
the  diffusion  of  the  vapour  which  it  gives  off  at  all  ordinary  temperatures, 
and  still  more  in  hot  workshops.  All  cloths,  &c.,  after  use  should  be  re- 
moved as  rapidly  as  possible  from  the  workshop,  to  avoid  exhalation  from 
them. 

There  is  one  other  means  of  general  and  great  importance  for  purifying 
the  air  of  the  rooms,  viz.  the  diffusion  of  the  vapours  of  ammonia  throughout 
them.  This  cannot  be  properly  done  while  the  men  are  in  the  workshops,  but 
at  night  when  they  have  left  it  should  be  done  freely.  The  very  best  results 
are  said  to  have  been  obtained  from  this  practice,  which  has  long  been  in 
operation  ;  but  the  rationale  of  it  is  not  apparent,  as  metalUc  mercury  does 
not  combine  with  ammonia.  In  the  works  at  Chauny  this  process  has  been 
employed  for  over  twenty  years  with  the  best  effects,  as  is  alleged. 

As  there  is  always  danger  from  the  mercury  which  gets  spilled  on  the  floor 
during  the  various  processes  in  which  it  is  used,  the  floors  should  be  made  of 
good  asphalte  to  prevent  its  absorption ;  and  by  keeping  the  floor  wet  the 
mercury  is  rendered  more  easily  visible.  By  giving  the  floor  an  incline,  and 
having  gutters  constructed,  the  collection  of  the  mercury  is  greatly  facilitated. 
It  will  also  be  found  a  great  advantage  to  have  in  the  workshops,  on  the  floors 


958  HYGIENE 

and  elsewhere,  quantities  of  tinfoil,  or  other  metal  which  readily  forms  an 
amalgam  with  mercury,  as  then  the  danger  will  he  mitigated,  and  pecimiary 
loss  by  waste  of  the  metal  greatly  diminished. 

LEAD 

This  metal  is  a  most  important  article  of  commerce,  and  is  used  in  a 
great  variety  of  industries.  The  specific  and  peculiar  character  of  the 
symptoms  produced  by  intoxication  with  lead,  and  the  fatal  results  which 
sometimes  follow,  combined  with  the  epidemic  occurrences  of  lead-poison- 
ing from  drinking  water,  have  attracted  a  great  deal  of  attention  to  the  sub- 
ject, and  still  there  is  much  which  is  mysterious  and  quite  unknown  in  con- 
nection with  the  familiar  diseased  condition  arising  from  absorption  of  lead. 

It  may  be  introduced  into  the  system  either  by  direct  absorption  through 
the  skin  or  mucous  membranes,  or  by  the  inhalation  of  the  vapoiu*  or  powder 
of  lead  or  its  compounds,  which,  produced  in  certain  stages  of  its  manufacture, 
or  by  the  extraordinary  variety  of  uses  to  which  compounds  of  lead  are 
put,  account  for  the  frequently  surprising  and  apparently  unaccountable 
occurrences  of  symptoms  of  plumbism  under  circumstances  which  at  first 
sight  would  seem  to  exclude  the  possibility  of  such. 

Among  the  workmen  who  are  most  exposed  to  the  danger  of  lead-poisoning 
may  be  mentioned,  besides  the  lead  workers  proper,  the  following  :  painters, 
gilders,  file-cutters,  type  and  note  founders,  calico  printers,  colour  grinders, 
glass  grmders,  bronzers,  enamellers,  &c. 

The  industries  in  which  lead  is  used  are  too  numerous  to  mention. 
Architects  and  builders  use  it  for  gutters,  roofs,  windows,  &c.  ;  it  is  used 
for  gas  and  water  pipes  ;  in  chemical  works  for  linings  for  sulphuric  acid 
chambers,  pans,  and  cisterns ;  tea-chests  are  lined  with  it ;  in  combination 
with  tin,  bismuth,  and  antimony,  it  forms  soft  solder  ;  while  white  metal  and 
brass  both  contain  it ;  printer's  type,  stereotype  metal,  organ  pipes,  and  a  host 
of  other  articles  are  formed  of  material  containing  lead. 

Chemical  compounds  of  the  metal  are  used  as  colouring  agents,  white, 
red,  and  yellow  lead  being  enormously  used ;  white  paint  and  white  papers 
most  commonly  have  lead  for  the  foundation  of  the  colour. 

Carbonate  of  lead,  or  white  lead,  is  very  extensively  used  as  a  paint,  and 
is  manufactured  on  an  immense  scale.  It  is  prepared  by  various  processes  : 
(1)  By  the  Dutch  method  it  is  obtained  through  the  action  of  a  weak  solution 
of  vinegar  on  coils  of  thin  sheet-lead.  The  grinding  of  this  carbonate, 
even  when  done  under  water,  is  very  dangerous  to  the  workmen.  (2)  By 
Thenard's  method  it  is  developed  directly  by  the  action  of  a  current  of  CO2 
on  the  lead.  (3)  The  CO2  given  off  in  the  combustion  of  coke  has  been 
employed  at  Birmingham  for  the  same  purpose.  The  carbonate  should  always 
be  sent  out  as  a  moist  substance. 

White  lead,  or  carbonate  of  lead,  PbCOg,  so  largely  used  as  a  pigment,  is 
still  mostly  made  by  the  old  and  dangerous  Dutch  process,  which  may  be 
thus  briefly  described.  On  the  tops  of  small  earthenware  pots,  containing 
acetic  acid,  thin  sheet-lead  is  placed,  and  the  pots  are  ranged  in  layers  of  tan, 
which  by  its  oxidation  maintains  sufficient  heat  to  keep  the  pots  at  a  mode- 
rately warm  temperature.  A  layer  of  wooden  planks  is  placed  over  the 
whole ;  then  another  layer  of  pots,  and  so  on  in  successive  layers  till  a 
'stack'  of  'blue  beds'  is  formed.  No  special  danger  is  incurred  in  the 
stacking  of  a  blue  bed.  The  acetic  acid  is  slowly  volatilised  by  the  heat 
evolved  by  the  oxidising  tan  ;  the  lead  is  oxidised,  combining  with  the  acid 
to  form  subacetate  of  lead,  which  is  again  decomposed  by  the  carbon  dioxide 


OFFENSIVE  BUSINESSES  959 

■evolved  from  the  tfin,  subcarbonate  of  lead  (carbonate  of  lead  or  white 
lead)  being  formed  ;  and  in  this  way  the  whole  of  the  lead  is  gradually 
converted  into  a  crust  of  white  lead.  The  stack  is  then,  after  the  lapse  of 
about  three  months,  converted  into  a  stack  of  '  white  beds ' — i.e.  of  white 
lead.  When  the  conversion  is  complete,  girls  enter  the  stack,  place  the 
white  lead  in  trays,  and  carry  those  chiefly  on  their  heads,  first  to  rolling  mills, 
where  the  crust  is  removed  from  any  undecomposed  lead,  and  subsequently 
to  heated  drying  stoves,  kept  at  a  temperature  of  about  200°  F.  After  being 
dried,  the  white  lead  is  ground,  washed,  and  then  dried  as  a  fine  powder. 
The  commercial  value  of  the  product  greatly  depends  upon  its  minute  state 
of  division,  white  lead  being  one  of  the  most  minutely  divided  of  known 
mineral  substances.  This  minuteness  of  its  particles  greatly  favours  the  dis- 
semination of  white  lead  as  dust  through  the  atmospliere,  and  aids  its  absorp- 
tion when  it  comes  in  contact  with  any  absorbing  surface  of  the  body.  It  is 
the  women  engaged  in  removing  the  white  beds,  and  in  the  stovhig,  grinding, 
and  packing  operations  who  are  the  greatest,  though  by  no  means  the  only, 
sufferers  from  plumbism. 

The  effects  of  working  in  white-lead  factories  are  insidious,  though  in  the 
■end  severe,  and  not  infrequently  fatal.  They  are  collectively  the  now  well- 
recognised  symptoms  of  plumbism  or  saturnine  poisoning  :  colic,  constipa- 
tion, irregular  and  profuse  menstruation,  wrist-drop,  and  other  forms  of 
paralysis  ;  pains  in  the  joints,  often  termed  'rheumatics,'  cachexia  ;  degene- 
ration of  the  liver  and  kidneys  ;  and  by  no  means  unfrequently  epileptiform 
convulsions,  ending  in  coma,  precede  a  fatal  termination  of  the  disease. 
Throughout  there  usually  is  the  well-known  and  characteristic  blue  line  of 
lead-poisoning  along  the  free  margin  of  the  gums,  due  to  a  deposit  of  sulphide 
of  lead. 

The  varnishing  of  leather  is  commonly  effected  by  the  use  of  red  and 
white  lead ;  what  is  termed  '  glace  '  leather  for  gloves  and  the  beautiful  glaze 
•of  visiting  and  playing  cards  contain  the  same  deadly  ingredient. 

The  beautiful  lustrous  leaves  and  flowers  which  represent  the  sparkling 
■dew  are  poisoned  with  lead,  and  some  of  the  most  lovely  artificial  flowers  are 
dyed  with  it  (the  white  with  carbonate  of  lead,  the  red  with  red  lead,  the 
yellow  with  chromate  of  lead). 

Artificial  jewels  mostly  contain  the  same  ingredient  and  are  pre- 
pared with  great  danger  to  the  workpeople  ;  and  the  glaze  of  the  commoner 
saucepans  also  contains  it.  A  poisonous  varnish  containing  litharge  is  used 
by  gilders  of  wood. 

Dressmakers  have  been  poisoned  by  using  silk  weighted  with  acetate 
of  lead  (sugar  of  lead),  through  moistening  the  ends  to  facilitate  threading 
their  needles  ;  and  tailors  have  had  the  same  fate  from  the  lead  employed  in 
dyeing  the  alpaca  they  were  working  on.  Even  the  preparations  of  lace 
and  straw  hats  are  commonly  associated  with  this  agent.  Painters  are 
notorious  sufferers,  several  of  their  colours  containing  lead,  and  white  paint 
containing  little  else  than  the  carbonate. 

Acetate  of  lead,  or  sugar  of  lead,  sometimes  particularised  as  'white,'  is 
prepared  by  dissolving  litharge  in  acetic  acid,  and  evaporating  to  crystallisa- 
tion. The  name  sugar  of  lead  is  no  doubt  due  to  its  appearance  and  sweet 
taste.  There  is  a  '  brown  sugar  of  lead,'  also  prepared  in  a  similar  way  by 
the  substitution  of  crude  acetic  or  pyroligneous  acid  for  the  purer  acetic 
acid.  This  salt  is  used  in  dyeing  and  printing,  and  formerly  (not  so  much 
now)  for  weighting  silk.  In  dyeing  it  is  largely  used  for  producing  chrome 
yellow  and  chrome  orange,  and  also  in  the  manufacture  of  the  acetates  of 
aluminium,  iron,  and  chromium.     It  is  also  used  in  making  hair-dyes. 


960  HYGIENE 

Nitrate  of  lead  is  prepared  by  dissohdng  litharge  in  hot  dilute  nitric^ 
acid.  Both  the  acetate  and  the  nitrate  are  used  in  cahco-printing  and 
cotton-dyeing  for  the  production  of  orange  and  yellow  colours.  In  the  latter 
operation,  after  the  cotton  has  been  printed  or  impregnated  with  a  solution 
of  the  lead  salt,  it  is  passed  through  a  solution  of  bichromate  of  potash. 
In  calico-printing  the  lead  may  be  fixed  as  sulphate  by  means  of  sulphate  of 
soda,  Li  these  cases  the  lead  acts  as  a  mordant,  the  colouring  matter  being 
the  chromic  acid  or  bichromate  of  potash. 

Sulphide  of  lead,  or  galena,  occurs  in  nature,  and  is  used  mainly  for 
glazing  pottery,  bricks,  &c.  Not  only  the  producers  of  these  articles,  but 
the  users  of  them,  may  be  infected  by  the  presence  of  lead  in  the  glaze. 

Lead  is  readily  acted  on  by  air,  the  brilliant  metallic  lustre  left  on  section 
becommg  tarnished  by  formation  of  a  thin  fihu  of  oxide  on  the  surface.  Air 
contained  in  water  also  acts  powerfully  on  lead,  while  Avater  deprived  of  air 
will  not  tarnish  lead  placed  in  it,  for  an  immensely  long  time.  When  lead 
is  placed  in  well-aerated  water,  the  film  of  oxide  formed  on  its  surface  is 
quicldy  dissolved  by  the  water. 

Shot  is  made  from  molten  lead,  which  is  allowed  to  fall  a  considerable 
height  (in  so-called  shot-towers)  mto  water.  It  is,  however,  not  pure  lead 
which  hardens  it,  but  an  alloy  of  lead  and  arsenic,  the  proportion  of  arsenic 
being  about  three  to  seven  per  1,000. 

Notwithstanding  the  numerous  opportunities  presented  of  seeing  lead- 
poisoning,  the  exact  nature  of  the  disease  is  still  far  from  being  thoroughly 
understood.  That  a  general  cachectic  condition  exists  in  persons  long  sub- 
jected to  the  action  of  the  poison  is  clear  ;  but  there  is  a  great  difference  of 
opinion  as  to  whether  the  blood,  or  some  special  organ,  is  chiefly  affected. 
Henle  considers  that  absorbed  lead  acts  mainly  on  unstriped  muscular  fibre, 
while  the  more  common  view  perhaps  is  that  the  nervous  system  is  the 
special  seat  of  attack. 

The  danger  of  mfection  among  workmen  much  exposed  to  the  inhalation 
of  the  fumes  of  the  metal,  or  to  dust  which  contains  it,  or  to  absorption 
through  the  skin  or  digestive  tract,  is  very  great.  When  the  symptoms 
appear  they  are  found  to  be,  although  multiform,  still  distinctly  uniform,  so 
iax  as  each  group  is  concerned,  and  characteristic.  Even  before  decided  symp- 
toms show  themselves,  the  patient,  by  his  '  facies  '  and  general  condition, 
betrays  the  approachuig  outbreak  of  disease.  This  prehminary  condition  may 
last  a  considerable  time.  There  is  usually  loss  of  flesh  and  loss  of  strength 
and  weight ;  the  face,  and  even  the  whole  skin,  assumes  a  peculiar  yellowish- 
grey  colour  (not  unlike  that  of  long-term  prisoners),  the  breath  becomes  un- 
pleasant to  smell,  there  is  a  pecuhar  dry  sweetish  flavour  in  the  mouth,  and 
the  very  characteristic  blueish-grey  line  appears  on  the  gums. 

The  blue  lead-line  on  the  gums  may  exist,  the  whole  gums  being  even 
black  for  years,  without  any  symptom  of  lead-poisoning,  and  it  may  be- 
absent  when  the  symptoms  are  well  marked.  It  is  probably  much  more  fre- 
quently a  local  deposit  than  a  result  of  elimination  of  lead  from  the  system. 
Microscopic  examination  of  the  parts  shows  black  granules,  situated  some 
inside  and  some  outside  the  capillaries,  and  probably  consisting  of  insoluble 
sulphide  of  lead.  The  sulphur  is  supplied  probably  from  decaying  organic 
remains  of  the  food  deposited  between  the  teeth,  &c. 

It  is  most  commonly  the  abdominal  organs  which  first  exhibit  decided 
symptoms  of  the  disease.  After  a  gradually  increasing  condition  of  constipa- 
tion, the  patient  begms  to  complain  of  more  malaise  than  is  usually  attributed  to 
that  cause,  with  a  feehng  of  tightness  in  the  belly,  which  is  hard  and  retracted. 
This  sensation  becomes  usually  a  more  or  less  severe  colicky  pain  situated 


OFFENSIVE  BUSINESSES  961 

about  the  umbilictis,  and  radiating  chiefly  downwards,  and  having  the  pecu- 
liarity of  being  reheved  by  pressure.  The  stomach  is  disordered,  and  vomiting 
frequently  occurs.  The  pains  extend  to  the  joints  and  muscles,  and  the  latter 
may  exhibit  already  at  this  stage  symptoms  of  paralysis,  and  the  urine  and 
salivary  secretions  are  both  scanty. 

The  remarkably  slow  pulse,  with  proportionately  increased  frequency  of 
the  respiration,  have  been  dwelt  on  as  almost  pathognomonic ;  thirty  con- 
tractions of  the  heart  per  minute  with  forty  and  more  inspirations  being  com- 
mon enough. 

Where  the  patient  is  obliged  to  continue  exposed  to  the  accumulative- 
action  of  the  poison,  convulsions  and  paralysis,  the  latter  as  a  common  occur- 
rence, ensue.  The  muscles  attacked  are  usually  those  of  the  upper  extremi- 
ties, and  more  particularly  the  extensors  of  one  or  both  arms.  The  supinator 
longus  and  the  deltoid  are  apparently  very  rarely  attacked.  The  sensibility 
of  the  affected  parts  is  generally  left  unimpaired.  Along  with  power  of 
contractility  the  muscles  are  found  to  have  lost  their  electrical  irritabihty, 
and  gradually  become  wasted  and  atrophied.  As  a  rule,  the  paralysis  is 
limited  to  the  muscles  supplied  by  the  musculospiral  nerve,  especially  those 
supplied  by  its  posterior  interosseous  branch. 

The  legs  are  sometimes  attacked,  and,  curiously  enough,  it  is  the  homo- 
logous muscles  to  those  in  the  arm,  the  extensors  of  the  leg  and  foot,  which 
are  mostly  affected. 

The  appearance  of  the  hands  in  paralysis  is  peculiar  and  characteristic,. 
and  is  well  expressed  by  the  popular  term  '  drop -wrist ' — '  main  en  griff e.' 

Secondary  misshapements  and  even  dislocations  may  occur,  and  mask 
the  simple  and  characteristic  appearances  usually  seen. 

More  serious  consequences  still  may  arise  in  the  shape  of  pronounced 
brain  symptoms  (encephalopathia  saturnina),  causing  usually  considerable 
loss  of  sensation  ;  there  may  be  even  complete  hemianesthesia,  without  much 
loss  of  motor  power.  Delirium,  convulsions,  and  coma  may  also  occur. 
Abortion  is  sometimes  produced  in  severe  cases.  Dr.  Eayner  reports  that 
the  proportion  of  painters,  plumbers,  and  glaziers  among  his  insane  patients 
w^as  nearly  one-third  more  than  among  the  general  population.^ 

It  will  be  seen  that  the  severity  of  the  disease  is  sufficient  to  demand  the- 
most  careful  means  for  its  prevention.  The  attacks  may  be  fatal,  or  may, 
while  yielding  to  treatment,  leave  permanent  ill-health,  and  more  or  less- 
deformity  and  paralysis  behind. 

From  the  great  variety  of  uses  to  which  lead  in  one  form  or  another  is 
put,  it  will  not  be  surprising  that  lead-poisoning  is  found  occurrmg  under 
most  various  conditions  and  where  least  suspected.  At  one  time  it  was  so 
prevalent  in  Poitou,  owing  to  its  addition  to  inferior  wines,  that  it  was  termed 
the  Mai  de  Poitou ;  it  was  very  common  once  in  Devonshire,  owing  to  the 
■use  of  lead  in  the  vessels  used  for  cider-making  ;  and  the  leaden  '  worms  ' 
used  in  the  distillation  of  rum  in  the  West  Indies  caused  it  to  be  prevalent 
there. 

It  occurs  among  cabinet-makers  from  the  use  of  glass-paper,  the  lead  in. 
the  fine  glass  dust  becoming  dissolved  in  the  sweat  of  the  hand  and  absorbed^ 
and  the  dust  being  also  inhaled.  A  liquid  containing  as  much  as  45  per  cent. 
of  lead  is  also  used  for  colouring  wood,  and  has  been  known  to  cause 
poisoning. 

The  glaze  of  tiles,  bricks,  and  pots  has  also  produced  poisoning,  generally 
consisting  as  it  does  of  a  large  proportion  of  sulphate  of  lead,  as  much  as 
equal  parts  of  this  salt  and  ground  sand  being  sometimes  used.     In  this  case, 
'  Journal  of  Mental  Science,  No.  CXIV.,  New  Series,  No.  78,  p.  223. 

VOL.  I.  3  Q 


962  HYGIENE 

too,  there  is  danger  from  the  inhalation  of  the  dust  arising  in  the  grinding 
process  as  well  as  fi-om  the  fumes  produced  during  the  baking. 

The  makers  of  pottery  and  faience  are  exposed  to  great  dangers  through 
the  poisonous  enamels  they  use.  One  brown  enamel  contains  52  per  cent,  of 
red  lead,  and  a  white  one  2  parts  of  red  lead,  with  4-4  parts  of  calcine  (which 
itself  contains  77  per  cent,  of  lead). 

The  dangers  chiefly  arise  during  (1)  the  powdering  of  these  ingredients 
(inhalation  and  cuticular  ab>;orption),  (2)  while  the  workmen  are  dipping  the 
vessels  in  the  water  to  which  the  powders  have  been  added  (cuticular  absorp- 
tion), (3)  when  they  are  being  burned  (inhalation  of  fumes,  and  absorption 
through  skin),  (-1)  during  a  process  sometimes  employed  of  dusting  the 
vessels  with  powdered  red  lead. 

Every  form  of  enamel  contains  lead,  chiefly  as  oxide,  combined  with  more 
or  less  ground  flint ;  a  white  enamel  contains  50  per  cent,  white  lead. 

In  jewellers'  workshops,  in  order  to  recover  every  particle  of  the  precious 
metals,  the  sweepings  are  collected,  and  after  the  formation  of  an  amalgam 
with  the  ash,  an  alloy  of  lead  is  made,  the  mercury  being  driven  off.  In  this 
process  lead-poisoning  may  occur. 

Among  the  other  more  important  trades  in  which  danger  from  lead- 
poisoning  is  liable  to  arise,  omitting  the  manufacture  of  the  various  lead 
compounds  already  named,  the  following  deserve  attention: 

1,  File- cutting.  The  plain  bar  of  soft  iron  which  is  to  be  made  into  a 
file  is  placed  on  a  flat  piece  of  lead,  as  a  substance  to  which  it  will  adhere 
slightly  without  slipping,  and  which  from  its  softness  does  not  cause  much  jar- 
ring when  struck.  The  teeth  of  the  file  are  cut  by  a  sort  of  blunt  chisel,  held 
in  one  hand,  which  is  struck  with  a  hammer  held  in  the  other.  Some  fifty  ox- 
sixty  such  strokes  or  more  will  be  given  in  a  minute,  and  each  stroke  cuts  a 
tooth  in  the  file.  It  is  evident  that  the  hands  of  the  file-cutter  are  almost 
constantly  in  contact  with  the  leadeii  bed  of  the  file ;  and  more  important, 
perhaps,  when  one  side  has  been  cut,  and  this  rough  side  is  turned  down  on 
the  lead,  there  is  a  good  deal  of  rubbing  away  of  the  lead  by  the  teeth  of 
the  file. 

All  the  larger  files  are  cut  by  men,  while  of  the  small  ones  a  large  num- 
ber are  cut  by  women. 

The  cutters'  hands  are  invariably  covered  with  dirt,  and  under  the  nails 
there  is  a  considerable  quantity  collected,  in  which  metallic  particles,  both  of 
iron  and  lead,  can  readily  be  detected  by  a  magnifying  glass  or  even  by  the 
unaided  eye.  The  rough  benches  or  tables  at  which  they  work  also  show 
dust  in  considerable  quantities,  of  which  a  large  part  is  lead. 

The  sweat  of  the  hands,  &c.,  undoubtedly  oxidises  and  dissolves  the  lead, 
and  absorption  then  readily  takes  place. 

2.  The  glass-cutter,  who  executes  his  often  highly  artistic  work  with  the 
simplest  apparatus,  sits  or  stands  in  front  of  a  revolving  grindstone,  usually 
some  8  to  10  inches  in  diameter,  and  of  various  thiclmesses  (from  about  1  inch 
to  2-3  inches  usually).  The  lower  part  of  the  stone  is  within  a  trough,  into 
which  the  water  constantly  supplied  from  above  falls,  as  well  as  the  fine 
particles  ground  off  the  glass.  The  article  to  be  '  cut '  is  held  against  the 
stone,  which  does  not  revolve  very  rapidly,  until  the  glass  is  sufficiently '  cut ' 
(really  rubbed  away),  when  its  position  is  altered,  and  the  '  cutting  '  is  con- 
tinued on  another  part. 

The  source  of  lead-poisoning  here  is  the  large  quantity  of  fine  glass 
powder  with  which  the  wet  hands  are  continually  in  contact,  the  glass  con- 
taining lead.  In  connection  with  this,  reference  may  be  made  to  the  occur- 
rence of  lead-poisoning  among  wood-polishers,  due  to  the  action  of  the 
■'  sand  '  paper,  really  made  with  ground  glass,  already  mentioned. 


OFFENSIVE  BUSINESSES  9G3 

3.  Type-founders  and  type-setters,  with  whom  may  be  classed  the  setters 
'Of  musical  type.     Type-metal  is  an  alloy  of  lead,  tin,  and  antimony. 

Type-setters  are  exposed  to  absorption  of  lead  from  constantly  handling 
this  compound,  and  also  from  a  common  habit  of  holding  type  in  the  mouth 
while  at  work.  Further,  there  is  often  a  good  deal  of  dust  about  in  the 
type  boxes  and  elsewhere  derived  from  the  type  itself.  Slight  scratches  on 
the  hands  favour  the  impregnation  of  the  system  with  the  metal  so  abun- 
dantly present. 

4.  The  connection  of  weaving  with  lead-poisoning  will  appear  very  remote 
at  first  sight.  But  a  knowledge  of  the  construction  of  the  Jacquard  loom 
will  show  that  with  certain  arrangements,  which  are  common  in  some  parts 
of  the  country,  there  is  considerable  risk.  The  long  cords,  known  as  '  harness 
cords,'  in  that  form  of  the  loom  are  kept  taut  by  weights  suspended  at  the 
end  termed  '  lingoes.'  A  small  loom  will  have  as  many  as  1,200  to  1,-500  such 
lingoes  and  cords,  a  large  one  5,000  to  6,000.  The  lingoes  are  rod-shaped 
weights  about  six  to  seven  inches  long  when  made  of  lead,  and  twelve  to 
fourteen  inches  long  when  made  of  iron.  About  twenty  of  them  make  one 
pound  in  weight.  As  they  hang  from  the  harness  cords  they  are  almost  all 
in  contact,  and  in  the  process  of  weaving  some  of  them  are  rising  and  falling 
almost  continually.  But  there  is  also  a  good  deal  of  oscillatory  motion  im- 
parted to  them  through  the  shaking  of  the  loom,  especially  in  hand-looms. 
The  waste  caused  by  this  friction  and  clashing  is  very  considerable,  and  in 
four  to  five  years,  with  hard  work,  a  whole  set  of  lingoes  may  be  so  worn  away 
as  to  be  too  light  for  use.  They  are  not  rubbed  away  uniformly  by  attrition, 
but  are  worn  in  little  notches,  evidently  due  to  striking  against  each  other 
rather  than  to  uniform  friction.  They  will  lose  in  this  way  some  30  to  40  per 
cent,  in  weight  in  four  to  five  years.  Taking  the  average  weight  of  twenty 
lingoes  to  one  pound,  this  would  give  300  lbs.  of  lead  to  6,000  lingoes,  the 
loss  of  which,  at  33  per  cent.,  would  give  100  lbs.  of  lead  rubbed  off  in  fine 
particles  on  an  average  during  four  to  five  years,  or,  say,  over  20  lbs.  per 
annum,  and  this  from  one  loom  only  in  a  room.  The  amount  of  such 
dangerous  material  given  off  from  some  scores  of  looms  in  a  weaving  shed 
would  therefore  be  a  very  serious  matter,  and  cause  grave  danger  of  lead- 
poisoning  to  the  workpeople. 

It  is  not  only  unnecessary  to  use  lead  for  lingoes,  but  it  is  much  more 
expensive,  and  iron  ones  are  also  to  be  preferred,  as  they  keep  their  shape  and 
position  better.  The  motion  of  the  lingoes  can  also  be  considerably  diminished 
by  placing  them  all  in  a  light  framework.  The  use  of  leaden  lingoes  is 
happily  going  much  out  of  use  in  some  parts  of  the  country,  and  iron  ones 
are  deservedly  growing  in  favour. 

In  the  manufacture  of  coloured  wall-papers  there  are  certain  processes 
fraught  with  grave  danger  to  the  workmen  from  the  nature  of  the  materials 
employed,  greatly  increased  by  the  mode  of  their  employment  in  the  produc- 
tion of  certain  effects. 

"Where  a  fine  white  ground  is  required,  this  is  often  produced  by  laying 
■on  white  lead ;  minium  is  employed  to  produce  red,  and  yellow  is  often  pro- 
duced by  using  other  compounds  of  lead — viz.  litharge,  chromate,  iodide,  or 
the  chloride  which,  combined  with  the  oxide,  is  known  as  Cassel  yellow. 

The  '  satining  '  of  white  paper  consists  in  producing  a  fine  lustrous  coat, 
chiefly  effected  by  friction  of  the  coating  of  white  lead.  In  this  operation  a 
great  quantity  of  fine  dust  is  produced,  which  is  inhaled,  swallowed,  or 
becomes  deposited  on  the  skin.  The  danger  of  lead-poisoning  is  therefore 
Tery  great. 

'  Velvet '  paper,  which  has  a  diill  rough  surface,  is  produced  by  covering 

3q2 


964  HYGIENE 

tlie  surface  of  tlie  paper  with  an  adhesive  coating  (starch,  &c.),  which  is 
powdered  with  cloth,  reduced  to  fine  dust,  and  coloured  vnth.  red  lead,  arsenical 
green,  &c.  It  is  easy  to  see  what  injurious  effects  may  be  produced  during 
the  production  of  this  material. 

Eulenberg  mentions  the  polishing  of  garnets,  as  carried  out  in  Hungary 
by  means  of  revolving  leaden  discs,  as  resulting  frequently  in  lead-poisoning. 

Lead  intoxicatioi  has  also  been  traced  to  the  use  of  leaden  pipes,  &c.,  in 
beer  macliines  ;  to  the  use  of  syphons  having  leaden  or  badly-made  white- 
metal  fixtures,  &c. 

The ,  extensive  spread  of  lead-poisoning  by  means  of  drinking  water 
affected  by  the  leaden  connecting  pipes  is  familiar  to  all  mechcal  men. 

Sanitary  Precautions. — The  mining  operations  are  not,  as  a  rule,  calcu- 
lated to  induce  any  special  danger  of  lead-poisoning,  but  there  may  be  great 
harm  done  by  allowmg  the  water  which  is  used  in  great  quantities  for  wash- 
ing the  finer,  broken  ore,  &c.,  to  make  its  way  into  streams,  ponds,  &c. 

During  the  smelting  there  is  always  more  or  less  vaporised  lead  given  off 
along  with  sulphur  dioxide,  &c.,  and  with  these  vapours  there  is  invariably 
present  PbS,  PbS04,  PbCOg,  &c.  Therefore,  smelting  always  necessitates  the 
employment  of  condensing  chambers  or  other  methods  for  preventing  the 
escape  of  these  vapours  into  the  atmosphere,  which  can  only  occur  with  great 
detriment  to  neighbouring  inhabitants  and  vegetation.  In  some  lead  works  in 
this  country,  long  flues,  sometimes  having  accessory  catch-chambers,  &c.,  are 
constructed  rising  up  the  sides  of  hills,  reaching  to  several  miles  in  length, 
Avhich  act  as  condensers,  and  as  much  as  five  to  six  hundred  tons  of  metal  have 
been  recovered  by  this  simple  means  in  a  year  at  one  manufactory.  The 
collection  and  removal  of  this  valuable  harvest,  won  by  very  simple  means  for 
the  owner,  requires  great  precautions  on  the  part  of  the  workmen,  and  should 
above  all  things  never  be  attempted  until  the  whole  of  the  parts  are  perfectly 
cooled.  Besides  lea.d,  the  flues  may  contain  other  products  directly  derived 
from  the  ore,  or  compounds  produced  during  the  smelting  ;  e.g.,  arsenic,  zinc, 
carbonate  and  sulphate  of  lead,  thallium,  tellurium,  molybdate  of  lead,  &c. 

The  condensation  can  be  greatly  facilitated,  and  danger  avoided,  by  the 
assistance  of  water,  which  may  be  applied  cold  in  the  form  of  a  rain  or  shower- 
bath,  or  as  steam.  By  this  means  the  fumes  are  thoroughly  mixed  with  the 
watery  vapour  and  the  most  satisfactory  results  are  obtained. 

In  the  manufacture  of  red  lead  there  is  a  large  amount  of  dust  produced, 
of  which  only  too  palpable  evidence  can  generally  be  obtained  on  entering 
the  premises.  The  escape  of  dust  or  vapour  from  the  furnaces  should  be 
most  carefully  avoided,  as  not  only  is  there  direct  danger  from  the  metallic 
dust,  but  it  gradually  becomes  oxidised,  and  soluble  salts  are  formed,  with 
greatly  increased  danger  to  animal  and  vegetable  life. 

The  grinding  of  the  minium  is  also  attended  with  danger,  and  should  be 
carried  out  in  a  closed  chamber,  provided  with  well-fitting  glass  windows  to 
allow  of  observation  of  the  progress  of  the  work.  Subsequently  the  powdered 
minium  has  to  be  filled  into  boxes  or  barrels,  an  unavoidably  dusty  operation, 
during  which  the  workmen  should  be  protected  by  sponges  or  cotton-wool  tied 
before  the  mouth  and  nose.  The  joints  of  the  cases  should  be  carefully  closed 
by  pasting  with  paper,  &c. 

The  manufacture  of  white  lead  is  much  more  dangerous  when  carried 
out  by  some  processes  than  by  others.  The  '  Dutch  method,'  already  de- 
scribed, leads  to  the  worst  results — mainly  from  the  destructive  action  of  the 
acetate,  which  causes  the  skin  to  crack  and  leaves  raw  surfaces  for  the 
direct  absorption  of  the  poison.  The  wearing  of  gloves  would  afford  protection 
in  this  process  ;    and  hberal  inunction  of  the  skin  of  the  hands  and  face 


OFFENSIVE  BUSINESSES  965 

is  of  great  service.  The  conveyance  of  the  salts,  after  collection  from  the 
surface  of  the  lead  spirals,  should  be  effected  with  care,  and  if  possible  by  the 
aid  of  shoots,  well  covered.  But  the  grinding  is  the  most  dangerous  part  of 
the  work.  This  should  never  be  done,  as  is  only  too  often  allowed,  with  an 
ordinary  hammer  or  pounder.  The  least  dangerous  method  is  pulverising  by 
rollers,  which  can  be  so  adapted  as  to  discharge  the  broken-up  material  of  any 
desired  degree  of  fineness.  The  whole  apparatus  should  be  covered  in  com- 
pletely, so  as  to  prevent,  as  far  as  possible,  the  escape  of  the  deadly  dust ; 
and  an  exhauster  should  be  applied  to  supply  fresh  air,  and  draw  off  the  dust 
into  a  special  chamber,  water  bath,  or  other  receptacle.  For  the  great 
majority  of  purposes  for  which  white  lead  is  required,  it  would  be  quite  as 
serviceable  in  the  paste  form,  made  up  with  oil,  and  prepared  in  this  form 
it  would  be  deprived  of  most  of  its  dangers.  In  order  to  grind  it  up  with  oil, 
it  is  not  necessary  to  dry  the  wet  powder,  as  the  water  is  forced  thoroughly 
out  of  the  powder.    Thus  several  dangerous  operations  are  completely  avoided. 

With  regard  to  the  personal  hygiene  of  the  workmen,  there  is  a  great 
deal  to  be  effected  by  means  which  are  simple  and  involve  no  hardships 
or  difficulties  whatever. 

Above  all,  personal  cleanliness  is  important,  nay  essential.  If  a  workman 
who  is  all  day  in  the  midst  of  a  very  dangerous  dust,  which  attaches  itself  to 
his  hair,  beard,  skin,  and  clothes,  enters  his  mouth  and  nose  and  ears,  gets 
beneath  his  clothes  and  adheres  to  his  skin,  will  not  keep  his  body  and  clothes 
clean,  then  it  is  hopeless  to  try  to  afford  him  protection  by  any  means  to  be 
devised.  His  hands  and  mouth  are  sure,  after  a  few  hours,  to  be  fouled  with 
lead  dust ;  he  should  therefore  rinse  his  mouth  thoroughly  from  time  to  time, 
and  wash  his  hands,  and  be  most  careful  never  to  take  any  food,  solid  or  liquid, 
until  this  has  been  done,  and  his  teeth  well  brushed.  The  nails  should  be 
always  kept  cut  short,  as  well  as  the  hair  and  beard,  as  otherwise  the 
poisonous  dust  will  get  deposited  in  them ;  the  clothes  should  be  made  as 
tight-fitting  at  the  neck  and  wrists  as  possible,  and  what  is  worn  in  the  work- 
shop should  be  left  there,  and  another  suit  worn  home.  Warm  baths  should 
be  provided  for  the  workpeople  in  all  such  works,  a  thing  which  can  be  done 
at  a  very  moderate  cost,  as  if  there  is  not  actually  hot  water  at  hand,  there  is 
always  steam,  by  which  a  bath  of  cold  water  can  be  quickly  warmed.  Every 
encouragement  should  be  given  to  the  workpeople  to  use  these  baths. 

If  circumstances  prevent  any  of  the  men  from  leaving  the  works  at  meal 
times,  it  is  essential  that  a  room  be  provided  for  meals  completely  detached 
from  the  dust-producing  works.  Workmen  who  have  already  shown  a  pre- 
disposition to  plumbism  should  not  be  allowed  to  continue  the  work  ;  and  all 
persons  having  an  open  cut  or  sore  should  be  excluded  until  it  is  quite  healed. 

As  already  mentioned,  there  are  stages  of  the  work  when  some  form  of 
respirator  is  essential  for  the  time,  and  fatty  inunction  is  very  useful  to  prevent 
the  hands  being  cracked. 

The  constant  use  of  acidulated  drinks,  e.g.  lemonade  made  with  sulphmic 
acid,  or  the  administration  of  iodide  of  potassium  for  any  length  of  time,  is 
quite  inadmissible.  Small  doses  of  sulphur,  or  of  sulphide  of  sodium,  are 
much  less  likely  to  undermine  the  health,  and  indeed  can  be  continued  for  a 
long  time  without  inconvenience,  and  even  advantageously.  They  favour  the 
formation  of  an  insoluble  sulphide  of  lead. 

The  drinking  freely  of  milk,  as  is  often  recommended,  can  do  no  harm,  if 
it  be  not  done  with  the  mouth  still  foul  with  lead  dust ;  and  if  the  milk  be 
not  kept  stored  in  the  workroom,  where  it  may  become  a  vehicle  of  poison 
to  the  drinker,  if  he  escape  other  means  of  intoxication. 

As  a  general  measure  of  precaution  it  is  highly  desirable  that  the  work- 


966  HYGIENE 

men  shoukl  be  carefully  examined  by  a  medical  man  at  short  intervals, 
especial  attention  being  shown  to  the  '  gum-line,'  the  complexion,  and  the 
state  of  the  nervous  system. 

JS^o  less  cleanliness  is  to  be  constantly  observed  in  the  case  of  the  work- 
shops than  in  the  person  of  the  workman.  They  must  be  kept  free  from  dust 
by  constant  sweeping  of  walls,  floor,  and  ceiling,  and  washing  when  needful. 
The  floors  should  be  cemented,  or  well  flagged,  so  that  they  can  be  thoroughly 
cleaned,  and  also  kept  moist,  to  allay  dust ;  for  which  purpose  a  little  chloride 
of  calcium  may  with  advantage  be  apphed  in  solution  to  the  floors. 

Men  inclined  to  excess  in  drinking  are  certainly  more  likely  to  be  reckless 
and  regardless  of  their  own  and  others'  welfare,  hence  they  are  a  danger  in 
lead  works  ;  whether  they  are  actually  more  susceptible  to  the  action  of  lead 
is  not  certain.  Strict  employers,  careful  of  their  men,  may  efiect  a  great  deal 
in  encouraging  them  to  attention  to  the  rules  of  the  shop,  which  should  be 
printed  in  large  form  and  hung  up  in  every  room.  Such  care  generally 
bears  good  fruit  in  the  health  of  the  men,  and  the  economical  success  of 
the  works. 

PHOSPHOEUS 

Phosphorus  does  not  occur  free  in  nature,  but,  owing  to  its  great  tendency 
to  combine  with  oxygen,  it  is  usually  found  united  with  that  element  and 
with  metals.  The  glowing  of  phosphorus  in  the  dark  is  due  to  slow  oxida- 
tion. Phosphate  of  calcium  is  the  most  important  of  the  natural  phosphates. 
Dry  bones  contain  some  88  per  cent,  of  neutral  phosphate  of  calcium. 
The  fossilised  excrement  of  extinct  carnivora,  iiiuler  the  name  of  coprolites, 
forms  a  large  depot  of  phosphate  of  calcium,  of  which  guano  also  largely 
consists. 

But  for  industrial  purposes  phosphorus  is  prepared  from  bone-ash,  the 
best  form  of  apparatus  being  that  known  as  Flecks'.  The  bones  are  calcined  to 
whiteness  for  some  hours,  then  broken  up  or  ground  and  treated  with  two- 
thirds  of  their  weight  of  sulphuric  acid  and  fifteen  to  twenty  parts  of  water. 
The  bone-ash  is  decomposed  by  the  sulphuric  acid,  sulphate  of  calcium  being 
formed.  Most  of  the  phosphorus  is  found  in  the  liquid  as  superphosphate  of 
calcium.  The  liquid  is  evaporated  to  the  consistence  of  syrup,  then  mixed 
with  one-fourth  its  weight  of  charcoal,  and  dried  by  heating  in  an  iron 
vessel.  The  dried  mass  is  heated  to  redness,  and  half  the  phosphorus 
distils  over  into  the  water,  beneath  the  surface  of  which  the  neck  of  the 
retort  opens,  the  other  half  remaining  combined  with  calcium  in  the  retort 
as  pyrophosphate.  The  phosphorus  thus  obtained  is  impure,  containing 
compounds  of  sulphur,  silicon,  carbon,  also  arsenic,  charcoal,  red  amor- 
phous phosphorus,  &c.  It  is  purified  by  pressing,  when  heated  under  hot 
water ;  or  chemically  by  treatment  with  bichromate  of  potassium  and  sulphuric 
acid,  or  with  nitric  acid.  It  is  usually  sold  in  the  form  of  sticks,  the  melted 
phosphorus  being  sucked  into  glass  tubes  by  the  use  of  india-rubber  balls ; 
or  Seulert's  apparatus  is  used — a  tinned-copper  vessel,  from  which  the 
liquefied  phosphorus  flows  through  a  horizontal  tube  with  a  tap,  connected 
with  which  are  suitable  glass  tubes  into  which  the  mass  falls.  When  the 
tubes  are  filled  the  tap  is  closed  and  the  phosphorus  allowed  to  solidify. 

During  the  burning  of  the  bones  most  offensive  vapours  are  given  off, 
which  also  include  offensive  dangerous  gases.  The  nuisance  is  perhaps  more 
annoying,  like  many  similar  ones,  to  those  living  around  the  works  than  to 
those  inside,  but  the  danger  is  considerable  to  the  workmen  during  various 
parts  of  the  manufacture.  Works  for  the  production  of  phosphorus  should 
not  be  allowed  to  be  carried  on  in  the  immediate  neighbourhood  of  towns. 


OFFENSIVE  BUSINESSES  007 

Besides  this  ordinary  yellowish  phosphorus,  there  exist  other  forms  due 
to  molecular  changes,  without  any  recognisable  change  of  chemical  composi- 
tion, A  red  or  amorphous  phosphorus  is  formed  by  heating  phosphorus 
in  a  closed  vessel.  It  consists  of  red  scales,  which  do  not  become  ignited 
on  coming  in  contact  with  the  air  until  it  reaches  a  temperature  above 
SGC  C.  (=  500°  F.),  when  it  becomes  reconverted  into  the  ordinary  form. 
This  red  or  amorphous  phosphorus  is  prepared  in  a  large  way  for  the 
manufacture  of  *  safety '  matches,  as  follows :  Phosphorus  is  heated  in  a 
porcelain  or  enamelled  iron  digester,  placed  in  a  double  bath,  the  one  next 
the  digester  being  filled  with  sand  or  paraffin,  the  outer  one  with  an  amal- 
gam of  tin  and  lead,  melting  at  250°  C.  (=482°  F.).  A  tube,  furnished  with 
a  stop-cock,  leads  from  the  digester,  which  is  closed  with  a  lid  (which  is 
again  covered  with  a  lid  enclosing  the  bath),  and  dips  into  a  vessel  of  stone- 
ware or  copper,  made  on  the  model  of  a  Woulfe's  bottle. 

The  vapours  from  the  digester  pass  through  this  tube,  and  are  condensed 
in  this  vessel.  Any  which  are  not  condensed  are  carried  off  by  a  double- 
bent  tube,  and  discharged  under  mercury  in  another  receptacle,  a  layer  of 
water  being  placed  above  the  mercury. 

Fumes  resulting  from  the  oxidation  of  the  phosphorus,  and  of  the  arsenic 
and  sulphur  which  exist  as  impurities  in  it,  are  given  off  during  this  pro- 
cess, including  arseniuretted  (AsHg)  and  sulphuretted  hydrogen  (H2S), 
phosphuretted  hydrogen  (PHg),  and  phosphoric  anhydride  (PgOg).  Hence 
great  precautions  have  to  be  taken  by  the  workmen  to  avoid  the  risks  involved 
from  inhaling  these  fumes. 

Phosphorus  is  used  on  an  enormous  scale  in  manufacture,  both  as  white 
phosphorus,  and  in  its  amorphous  (red)  form. 

The  manufacture  of  matches  is  so  important  as  to  deserve  more  than  passing 
reference.  In  Sweden  and  Germany  it  is  carried  on  on  an  enormous  scale, 
and  there  are  in  Neustadt  alone  some  seventy  factories.  So  early  as  1816, 
Derosne  in  Paris  produced  matches  which  were  made  with  finely-divided  white 
phosphorus  and  sulphur.  Some  twenty  years  later  an  improved  method  was 
introduced  at  a  large  manufactory  estabhshed  for  the  purpose  at  Frankfort-on- 
the-Main,  by  Trevany,  Eomer,  and  Bottger.  Instead  of  chlorate  of  potassium, 
an  expensive  and  explosive  material,  liable  to  cause  injury  to  the  user,  and 
spoil  the  matches,  they  employed  as  the  oxidiser  peroxide  of  manganese, 
nitrate  of  potassium,  litharge,  brown  lead  (Pb02,  superoxide),  nitrate  of 
lead,  &c.,  and  other  substances  whose  combustion  is  less  violent  than  is 
the  case  of  chlorate  of  potassium.  Instead  of  gum  arable  they  employed  glue 
to  fix  the  mass  to  the  wooden  chips,  a  material  which  dries  much  quicker 
than  gum.  The  wood  is  cut  by  machinery  into  thin  plates,  the  thickness  of 
a  match,  and  these  are  subsequently  cut  into  sticks  of  the  required  size. 
Bound  wooden  matches  are  made  by  cylindrical  knives,  of  which  a  number 
of  the  requisite  bore  are  fixed  in  a  frame.  In  smaller  factories  the  machine 
labour  is  replaced  by  hand  labour.  The  wooden  stems  are  fixed  in  a  frame,  so 
that  the  ends  shall  all  stand  at  one  level,  3,000  to  6,000  in  each,  and  dipped 
in  the  materials  which  make  the  'head,'  and  fix  it  properly.  As  the 
phosphorus  is  so  highly  inflammable,  it  is  necessary  to  interpose  some  slower 
medium  between  it  and  the  wood,  otherwise  the  phosphorus  would  be  burned 
out  without  the  wood  ever  becoming  ignited.  Sulphur  is  very  commonly  used 
for  this  purpose,  when  resinous  wood  is  employed  ;  in  the  case  of  non- 
resinous  woods,  such  as  elm,  birch,  poplar,  aspen,  &c.,  wax,  paraffin,  &c.,  are 
used  instead  of  sulphur.  The  sulphur  is  melted  in  a  shallow  iron  pan,  at  as 
low  a  temperature  as  possible,  to  avoid  ignition,  or  the  passage  of  the  sulphur 
into  a  thick  unworkable  condition.     The  most  suitable  temperature  is  about 


908  HYGIENE 

235°  F.  In  some  works  double-walled  receptacles  are  used,  with  steam  at  tins 
temperature  circulating  between.  The  wooden  stems,  fixed  in  their  frame, 
haA-ing  been  warmed  on  a  sort  of  hot-hearth  close  at  hand,  to  ensure  more 
even  distribution  of  the  molten  sulphur,  are  dipped  into  it  to  the  required 
depth  and  raised,  superfluous  sulphur  being  removed  by  giving  the  frame 
a  shake.  Li  smaller  factories  considerable  danger  arises  fi'om  all  the  opera- 
tions being  carried  on  in  the  same  place,  and  the  same  fire  often  being 
employed  for  the  sulphuring  and  the  subsequent  application  of  the  igniting 
material.  Owing  to  this  the  workmen  are  exposed  to  the  vapours  of  phos- 
phorus, as  well  as  to  others  arising  during  the  sulphuring,  which  is  often 
c;ii-i-ied  on  at  such  a  temperature  as  to  cause  danger  not  only  of  its  ignition 
but  also  the  development  of  sulphur  vapour  to  a  most  distressing  degree. 

The  igniting  mass  is  formed  of  white  phosphorus,  which  should  not 
amoiuit  to  more  than  G  to  8  per  cent,  of  the  mass  '  melted  under  hot  water, 
and  mixed  with  some  of  the  oxidising  materials  already  mentioned,  and 
some  kind  of  material  to  fix  it  on  the  match  (usually  glue,  dextrin,  gum,  &c.), 
and  some  colouring  material  (such  as  umber,  ultramarine,  lampblack,  and 
various  aniline  colours,  &c.)  ;  this  is  used  either  hot  or  cold.  The  fixing 
medium  is  first  dissolved  in  water,  then  heated  in  an  enamelled  iron  pot, 
with  a  very  exactly  fitting  lid ;  the  phosphorus  is  then  added,  and  the  lid,  to 
which  a  stirring  apparatus  is  fixed,  carefully  closed.  When  the  phosphorus 
is  thoroughly  distributed,  the  colouring  matter  and  oxidiser  are  added, 
and  after  careful  stirring  the  operation  is  complete. 

The  likelihood  of  phosphorus  fumes  escaping  during  these  processes,  to  the 
detriment  of  the  workmen,  is  very  great,  and  to  ob\date  tbe  risks  it  requires 
careful  management  and  good  appliances.  Subsequently  the  matches  are  left 
in  the  frames  in  warm  air  (not  much  above  85°  F.),  until  they  are  quite  dried, 
when  they  are  taken  out  of  the  frames,  and  made  up  in  bundles,  or  put  direct 
into  boxes.  The  drying  should  never  be  done  by  the  direct  heat  of  a  fire, 
but  should  always  be  effected  by  a  current  of  warm  air.  In  some  works — ■ 
and  it  is  most  desirable  that  the  method  should  be  universally  adopted — a 
good  deal  of  this  work  is  done  by  machinery.  The  workmen  are  exposed  to 
great  risk  here  from  vapour  arising  from  the  matches,  from  fire,  and  from  the 
action  of  the  match  heads  on  the  skin,  especially  if  it  should  be  raw  or  sore. 

'  Safety  '  matches  are  made  with  red  or  amorphous  phosphorus,  which, 
as  stated,  does  not  take  fire  in  the  air  until  heated  above  2G0°  C.  (=■  500°  F.), 
when  it  is  converted  into  the  ordinary  form  of  phosphorus,  and  burns  with 
formation  of  phosphoric  anhydride.  The  phosphorus  is  contained  in  the 
rough  rubbing  surface  on  the  box,  and  not  in  the  match-heads.  This  ignit- 
ing material  is  fixed  by  glue,  or  other  suitable  medium,  to  the  surface,  and 
is  composed  of  chlorate  of  potash,  from  10  to  40  per  cent,  iron  pyrites, 
peroxide  of  manganese,  powdered  glass,  sulphide  of  antimony,  and  a  suitable 
•cidhesive — e.g.  of  glue. 

These  materials  are  ground  and  mixed  to  a  fine  paste.  Great  care  is 
requisite  to  prevent  the  chlorate  of  potash  exploding,  and  with  this  object 
it  is  ground  in  a  wooden  vessel,  provided  with  a  special  cover  for  allowing 
immediate  escape  to  the  gases  should  an  explosion  occur.  The  adhesive 
is  first  dissolved  in  boiling  water,  next  the  lead  compounds  are  added,  and  the 
other  constituents  afterwards ;  the  chlorate  of  potash  being  added  last.  The 
rubbing  surface  is  prepared  in  a  similar  way,  the  amorphous  phosphorus 
being  added  last. 

'  In  England  the  proportion  is  commonly  much  larger,  but  this  only  renders  the  match 
more  dangerous  as  an  explosive,  and  as  affecting  the  health  of  the  maker ;  a  smaller  pro  - 
portion  is  quite  as  efficient  for  ignition. 


OFFENSIVE  BUSINESSES  969 

The  match-sticks  are  dipped  in  a  mixture  consisting  of  chlorate  of  potash, 
peroxide  of  manganese,  bichromate  of  potash,  red  lead,  subsulphide  of  lead, 
and  sometimes  picric  acid,  with  a  suitable  adhesive,  such  as  starch,  glue, 
&c.  As  in  the  case  of  ordinary  matches,  some  material  is  added  to  diminish 
the  violence  of  the  ignition,  such  as  sulphur,  oxide  of  iron,  umber,  powdered 
glass,  &c.^ 

The  people  engaged  in  the  manufacture  of  phosphorus  and  its  compounds, 
and  in  their  utilisation  for  commercial  purposes,  are  exposed  to  grave  danger 
at  various  stages  of  the  work,  and  at  certain  stages  great  nuisance  is  caused 
to  those  living  around  the  works.  Those  engaged  in  the  earlier  stages 
of  bone-burning,  and  such  preparations,  may  live  fairly  healthy  lives,  if  even 
moderate  care  be  taken,  but  the  manufacture  of  matches  is  often  carried  on 
so  as  to  imperil  the  health  and  lives  of  the  workpeople  grievously.  There  is 
one  disease,  unfortunately  too  well  known,  which  is  specific  to  those  engaged 
in  this  trade,  that  is,  the  disease  of  the  bones  (phosphorus-necrosis),  which  is 
mostly  limited  to  the  jaws,  and  more  particularly  to  the  lower  jaw. 

There  is  no  reason  why  the  bone-burning  should  not  be  carried  on  sub- 
ject to  the  action  of  a  fan  which  would  conduct  the  offensive  fumes  either 
directly  into  a  furnace,  where  the  offensive  odour  would  be  destroyed,  or  still 
better,  into  a  reservoir  containing  water,  where  they  would  be  condensed,  and 
the  accompanying  fumes  would  either  be  absorbed  or  conducted  further,  after 
passing  through  the  bath,  into  a  high  chimney.  Dust  from  the  burned 
bones  is  very  liable  to  cause  irritation  of  the  eyes  and  mucous  membranes, 
wliich  is  often  very  troublesome. 

During  the  subsequent  distillation  of  the  bones,  very  offensive  vapours 
are  produced,  which  can  be  best  treated  as  suggested  above.  When  the 
bones  are  treated  with  sulphuric  acid,  sulphuretted  hydrogen  and  carbon 
dioxide  are  freely  developed,  as  well  as  smaller  quantities  of  compounds  of 
hydrogen  with  chlorine,  fluorine,  and  arsenic,  also  hydrocyanic  acid.  Sub- 
sequently, when  the  mass  becomes  heated,  sulphuric  and  sulphurous  acids 
are  evolved  in  large  quantities,  and,  as  the  sulphuric  acid  is  impure,  arsenic 
and  arsenious  acid  are  always  present.  Active  ventilation  is  absolutely 
essential  to  prevent  danger  from  these  gases.  It  has  been  suggested  to 
conduct  them  into  a  receptacle  filled  with  burned  bones — which  would 
facilitate  their  disintegration. 

During  the  distillation  of  the  impure  phosphorus,  dangerous  gases  of  a 
similar  character  are  evolved,  and  the  fire  must  be  gradually  lowered  to  avoid 
ignition  of  the  phosphorus  which  has  condensed  on  the  sides  of  the  recep- 
tacles. The  workmen  who  fill  and  empty  the  retorts  should  always  be  care- 
fully dressed,  so  as  to  protect  as  much  of  the  surface  of  the  body  as  possible, 
and  wear  masks  provided  with  glass  protectors  for  the  eyes,  while  the 
respiratory  organs  should  be  protected  by  cotton-wool  or  cloths.  In  this  stage 
of  the  work,  free  ventilation  to  dilute  and  expel  the  gases  is  essential.  When 
the  retorts  have  been  heated,  they  must  never  be  opened  more  than  is  abso- 
lutely necessary,  and  they  must  be  slowly  cooled  to  prevent  the  risk  of  fracture, 
and  the  escape  of  phosphoric  vapours  in  great  quantities.  In  the  rectifica- 
tion of  phosphorus  with  nitric  acid,  extreme  care  must  be  taken  to  make  all 
parts  of  the  apparatus  which  conducts  away  the  nitrous  fumes  (vapour  of 

'  Efforts,  which  it  is  to  be  hoped  may  be  crowned  with  success,  are  continually  being 
made  to  produce  a  match  without  the  use  of  phosphorus.  As  oxidisers  the  following 
have  been  tried:  nitrate  of  lead,  picrate,  chlorate,  bichromate  and  permanganate  of 
potash,  &c. ;  as  the  igniting  substance,  iron  pyrites,  sulphur,  carbon,  (fee, ;  and  as  sub- 
stances to  diminish  the  force  of  explosion,  sand,  powdered  glass,  umber,  with  the  same 
adhesives  as  are  used  in  the  case  of  other  matches. 


970  HYGIENE 

phosphorus,  &c.),  air  tight.  The  admixture  of  a  stream  of  COg  would  be 
advantageous  as  diminishing  the  risk  of  explosion. 

As  the  vapour  of  phosphorus,  owing  to  its  weight,  sinks  to  the  ground,  it 
is  of  the  greatest  importance  to  employ  aspii'ators  to  enforce  an  upward 
current  of  air  in  the  workshops. 

The  storing  of  phosphorus  is  a  matter  wliich  should  be  done  with  the 
greatest  foresight  and  care.  It  should  always  be  kept  in  glass  or  earthen- 
ware vessels  in  water,  and  still  better  in  such  vessels  which  are  placed  inside 
another  of  the  same  kind  for  greater  safety.  These  should  be  kept  in  a  cool 
place  away  from  all  risk  of  breakage. 

During  carriage,  these  should  be  enclosed  in  met:»llic  (tin)  vessels  filled 
with  water,  and  made  to  hold  only  a  certain  maximum  quantity,  and  not  to 
exceed  a  certain  maximum  weight.  They  should  be  provided  with  proper 
means  for  bemg  lifted,  to  avoid  danger,  and  invariably  be  labelled  to  show 
which  is  the  upper  side. 

The  manufacture  of  red  or  amorphous  phosphorus  may  lead  to  the 
development  of  similar  gases  to  those  evolved  in  the  distillation  of  white 
phosphorus,  owing  to  the  impurities  in  the  phosphorus  which  is  used  for 
conversion  into  the  red  form  ;  but  though  cases  of  intoxication  do  occur 
from  this  substance,  they  are  rare  as  compared  with  those  caused  by  white 
phosphorus.  The  operations  can,  however,  be  conducted  in  a  less  dangerous 
manner,  but  if  care  be  not  taken,  in  the  closing  of  the  digester,  to  make  it  air 
tight,  and  in  the  opening  of  it  to  avoid  the  escape  of  the  noxious  fumes,  the 
workmen  will  unavoidably  be  exposed  to  most  offensive  and  dangerous  fumes. 

That  water  which  has  been  used  during  the  process  of  manufacture,  and 
contains  any  phosphorus  or  other  dangerous  ingredient,  should  not  be 
allowed  to  leave  the  works  untreated,  and  more  particularly  to  enter  any  well 
or  stream,  is  a  matter  of  primary  importance.  It  has  been  found  profitable 
and  otherwise  advantageous  to  evaporate  such  water  in  shallow  pans  placed 
mside  the  machmery.  A  considerable  quantity  of  phosphorus  may  be  re- 
covered in  this  way. 

The  greatest  of  aU  the  industries  in  which  phosphorus  is  engaged  is 
match-making.  From  the  description  given  of  the  process,  the  nature  of  the 
dangers  incurred  will  already  be  understood. 

As  might  be  expected,  all  the  eAdls  connected  with  the  trade  are  found  in 
their  worst  form  in  small  factories,  and  where  the  work  is  carried  on  in  the 
workmen's  houses.  Here  it  is  impossible  to  provide  the  large  airy  rooms, 
the  artificial  ventilation,  the  air-tight  receptacles,  and  other  things  which  are 
essential  to  the  carrymgon  the  work  without  serious  danger  to  the  workpeople. 

At  the  very  commencement  of  the  operation  of  match-making,  the  work- 
people are  exposed  to  great,  and  even  serious  inconvenience  from  a  cause 
which  is  quite  preventable.  When  the  cut  chips  are  brought  for  dipping,  the 
bundles  contain  a  great  quantity  of  the  finest  wood  dust,  which  is  liable  to 
cause  irritation  of  the  respiratory  passages.  This  could  be  easily  prevented 
by  exposing  the  chips  to  the  action  of  a  fan  for  a  short  time. 

The  more  serious  affections,  however,  from  which  the  match-makers  suffer 
are  those  arising  from  the  presence  of  phosphorus  in  the  match-heads,  and 
from  the  sulphur  employed  in  the  manner  described.  If  the  sulphur  be 
heated  too  much  there  is  danger  of  ignition,  and  of  the  development  of  large 
quantities  of  noxious  fumes.  At  the  best  it  requires  more  attention  than  is 
usually  devoted  to  the  matter  to  prevent  the  temperature  of  the  sulphur 
being  unnecessarily  raised,  and  the  consequent  production  of  SO2  in  consider- 
able quantities  ;  there  is  always  some  given  off  during  this  process. 


OFFENSIVE  BUSINESSES  971 

The  pans  in  which  this  sulphuring  is  done  should  be  covered  with  a 
proper  lid,  provided  with  a  pipe  to  conduct  away  the  fumes  into  a  tall 
chimney,  if  they  cannot  be  utilised,  as  such  things  usually  can  be.  In  small 
factories  the  sulphuring  and  the  dipping  in  the  explosive,  which  contains 
the  phosphorus,  are  often  done  at  the  same  fire,  and  with  no  arrangements 
for  protecting  the  workmen  from  the  combined  action  of  sulphur  and  phos- 
phorus fumes. 

The  preparation  of  the  explotsive  material  is  the  most  dangerous  part  of 
the  whole  manufacture. 

This  should  be  absolutely  prohibited  in  cases  where  it  can  only  be  done 
in  open  vessels  ;  and  the  provision  of  proper  vessels  heated  by  steam  or 
water,  with  air-tight  covers,  means  of  carrying  off  offensive  vapours,  and 
safety-valves  to  prevent  danger  from  explosion  (by  permitting  the  ready 
escape  of  gases  suddenly  evolved)  should  be  made  a  sme  qud  non. 

The  employment  of  a  warm  adhesive  (glue,  &c.)  has  such  disadvantages 
that  the  use  of  cold  starch  and  dextrin  has  been  suggested  as  an  advanta- 
geous substitute.  But  this  does  not  quite  meet  the  difficulties,  as  it  is  necessary 
to  dry  the  cold  adhesive  at  an  increased  temperature,  which  in  turn  leads  to 
the  evolution  of  phosphorus  vapours.  When  gum  has  been  used  as  a  fixer, 
the  'head'  is  very  liable  to  soften,  come  off,  and  adhere  to  the  hands  if 
they  are  at  all  moist  from  sweat,  &c.,  and  it  is  on  the  whole  better  to  use 
glue  as  a  fixer,  as  it  dries  so  much  quicker  (30  to  40  minutes),  and  its  dis- 
advantages are  so  much  more  quickly  got  over. 

The  removal  of  the  finished  matches  from  the  frames,  and  the  putting 
them  up  in  bundles  for  boxing,  or  in  larger  packets,  involves  considerable 
danger  of  ignition  ;  and  some  part  of  the  '  heads  '  is  liable  to  get  rubbed  off 
in  the  form  of  dust,  and  to  adhere  to  the  skin  and  cause  absorption  or 
irritation  of  any  existing  raw  places.  Great  caution  is  required  in  the 
operation,  and  vessels  of  water  should  always  be  close  at  hand. 

The  importance  of  large  roomy  workshops  with  good  ventilation,  assisted 
by  fans  or  flues  set  in  action  by  heat  (connection  with  the  chimney,  &c.), 
cannot  be  over-rated,  the  ventilation  being  directed  upwards,  to  counteract 
the  tendency  of  the  heavy  vapour  to  sink ;  extreme  personal  cleanliness, 
maintained  by  frequent  baths  and  washing  of  the  mouth  and  hands,  espe- 
cially before  partaking  of  food,  should  also  be  constantly  observed. 

No  food  or  drink  should  be  taken  in  the  workshop,  and  the  working 
clothes  should  not  be  worn  at  home. 

A  very  important  condition  of  preservation  of  the  health  of  these  workers 
is  the  diminution  of  the  work  to  the  shortest  possible  time,  and,  where  it  is 
possible,  to  allow  those  engaged  in  the  more  dangerous  part  of  the  work  (e.g. 
the  preparation  of  the  material  for  ignition)  to  take  on  at  intervals  some 
other  work  for  a  time.  The  benefits  to  be  derived  from  the  presence  of  the 
vapour  of  turpentine,  as  described  first  by  Letheby,  have  been  generally 
recognised,  and  in  many  works  little  vessels  of  tin  containing  turpentine  are 
placed  in  the  workshops,  and  the  workpeople  carry  flasks  or  sponges  attached 
by  a  string  at  their  chests,  so  that  they  may  have  the  advantage  of  breathing 
air  impregnated  with  the  vapour.  Its  administration  internally  in  case  of 
phosphorus  intoxication  is  recommended.  Advantage  is  also  to  be  derived 
from  washing  the  mouth  with  a  weak  alkaline  solution — e.g.  carbonate  of 
sodium.  Washing  the  teeth  with  this,  or  with  lime-water  and  charcoal,  is 
also  to  be  recommended.  The  use  of  masks  filled  with  charcoal  has  also 
been  recommended. 

Where  the  benefits  of  the  oxidation  derived  from  turpentine  vapours 
cannot  be  utilised,  owing  to  mdividual  inability  to  endure  the  turpentine 


972  HYGIENE 

fumes,  it  has  been  recommended  to  use  watery  solution  of  sulphate  of  copper, 
as  it  leads  to  precipitation  of  phosphorus  as  phosphate,  along  with  metalhc 
copper.  The  addition  of  charcoal,  a  powerful  absorbent  of  phosphorus,  to 
the  solution  would  also  be  beneficial. 

The  effects  of  poisoning  with  phosphorus  may  be  either  acute  or  chronic. 
The  symptoms  appear  much  more  rapidly  after  swallomng  phosphorus  when 
finely  divided  than  when  m  a  solid  piece. 

Cln-onic  intoxication  is  generally  slow  and  insidious,  and  seldom  shows  itself 
for  tliree  to  four  years  after  the  commencement  of  work  in  a  factory.  It  is  much 
more  common  in  match-factories  than  in  any  other  works  connected  with  the 
use  of  phosphorus.  Before  any  very  marked  symptoms  are  noted,  there  are 
observable  loss  of  flesli  and  a  gradual  change  of  colour  to  a  yellowish  tinge. 
The  appetite  fails,  and  gastric  and  intestinal  disorders  are  common  ;  indeed, 
gastric  catarrh  might  be  commonly  supposed  to  be  tlie  chief  ailment.  Head- 
ache and  dulness  of  the  mental  faculties  become  marked,  and  dyspnoea  and 
bronchitis  are  common.  Toothache  and  pains  in  the  jaws  become  almost 
constant ;  later  on  the  gums  swell,  become  tender,  and  ulcers  form,  discharg- 
ing large  quantities  of  stinking  matter,  and  the  ulceration  tends  to  extend 
and  become  very  destructive.  At  the  same  time  the  breath  becomes  very 
offensive. 

Then  the  bone  can  generally  be  found  to  be  diseased  by  the  use  of  the  sound. 
In  a  more  advanced  stage  the  gums  as  well  as  the  periosteum  become  quite 
detached  from  the  bone,  and  the  alveolar  processes  are  exposed  to  view. 
The  course  of  events  is  usually  more  rapid  and  serious  when  the  lower  jaw 
is  attacked  than  when  the  upper  one  is,  disease  of  the  latter  being  much  the 
less  frequent,  in  the  proportion  of  about  three  to  five,  possibly  because  the 
lower  jaw  is  more  in  contact  with  the  saliva,  which  always  contains  phos- 
phorus— the  cause  of  all  the  evil.  Sometimes  the  necrotic  action  proceeds 
stealthily,  and  not  in  the  somewhat  stormy  manner  which  is  usual,  and  the 
patient  will  lose  many  teeth  before  any  other  serious  symptoms  appear  ;  or  a 
long  sequestrum  may  be  discharged  before  he  has  realised  the  true  state  of 
affairs.  The  existence  of  carious  teeth  is  commonly  assumed  to  be  the  chief 
agency  in  the  commencement  of  the  disease,  by  giving  an  entry  to  the  phos- 
phorus into  the  interior.  General  breakdown  of  the  health  is  a  natural 
result  of  such  a  condition,  the  intoxication,  pain,  and  malnutrition  combining 
to  reduce  the  patient  to  the  most  miserable  state.  The  frequency  of  this 
frightful  disease,  according  to  Hirt,  was  formerly  not  less  than  11  to  12 
patients  yearly  to  every  100  matchmakers,  without  regard  to  age  or  sex  ; 
its  gravity  may  be  judged  from  the  statement  that  one  in  two  attacked  are 
said  to  die,  the  condition  of  many  who  recover  from  a  severe  attack  being 
most  wretched.     It  is  now  not  common  in  this  country. 

The  complete  suppression  of  the  use  of  white  phosphorus  is  the  great 
preventive.  Failing  that,  suitable  large  rooms  ;  good  ventilation  artificially 
conducted  upwards  ;  suitable  apparatus  to  carry  off  vapours  and  dust ;  and 
personal  care  on  the  part  of  the  workpeople — are  what  must  be  rehed  on  to 
avert  or  minimise  the  evils. 

ZINC 

Zinc  is  never  found  native,  but  its  ores  occur  in  abundance.  The  chief 
are  calamine,  or  carbonate  of  zinc,  blende,  or  sulphide  of  zinc,  and  a  red  oxide, 
the  colour  of  which  is  due  to  the  presence  of  the  oxides  of  iron  and  manganese. 

The  extraction  of  zinc  from  its  ores  commences  with  the  crushing  of  the 
■ore,  which  is  subsequently  roasted,  dming  which  process,  when  blende  is  used, 
the  sulphur  passes  into  sulphur  dioxide,  the  zinc  becomin     oxidised.     The 


OFFENSIVE  BUSINESSES  973 

roasted  ore  is  mixed  with  half  its  weight  of  powdered  coke  or  anthracite  and 
subsequently  reduced  (deoxidised)  by  one  of  two  processes,  known  as  the 
English  and  the  Belgian.  The  English  method  is  one  of  distillation  down- 
wards {per  descensum).  The  above  mixture  is  put  into  crucibles  having 
an  opening  in  the  bottom  with  a  short  iron  pipe,  and  a  lid  which  is  carefully 
luted  over.  A  number  of  these  crucibles  are  placed  on  the  fire-bars  within 
a  circular  furnace.  After  a  time  carbonic  oxide  escapes  through  the  pipe 
in  the  bottom,  and  burns  with  a  blue  flame,  which  becomes  white  and 
deposits  white  fumes  of  oxide  of  zinc.  This  flame  is  then  extinguished, 
and  a  longer  tube  attached,  through  which  the  metal  falls  into  vessels 
provided  to  receive  it  below.  As  the  zinc  is  volatile  at  high  temperatures, 
and  boils  at  a  bright  red-heat,  it  distils  downwards  in  this  way.  The  metal 
thus  obtained  is  impure  and  contains  a  good  deal  of  oxide  and  requires  re- 
melting  and  skimming,  after  which  it  is  cast  into  ingots  ;  but  the  commercial 
zinc  usually  contains  some  lead  and  iron  as  impurities. 

Zinc  is  very  little  acted  on  by  the  atmosphere.  It  loses  its  brilliancy 
when  exposed  to  moist  air,  owing  to  the  formation  of  a  thin  pellicle  of  oxide, 
which  protects  it  from  further  change.  This  property  and  the  facility  with 
which  it  can  be  rolled  into  sheets  when  hot  make  it  available  for  many  uses. 
It  is  largely  used  in  the  form  of  '  galvanised '  iron-sheets  for  roofing,  &c. 
The  sheets  of  iron  are  covered  with  a  coating  of  zinc  either  by  being  dipped 
in  molten  zinc,  covered  with  a  layer  of  sal-ammoniac,  which  dissolves  the  oxide 
which  forms  on  the  zinc ;  or  by  first  coating  the  zinc  with  tin,  by  galvanic 
action,  and  then  dipping  in  the  molten  zinc. 

Galvanised  iron  wire  is  also  very  largely  in  use  for  various  purposes,  of 
which  the  most  important  are  for  telegraph  wires  and  for  wiring  down  cham- 
pagne, mineral  waters,  and  other  effervescing  drinks.  Brass  and  copper  are  also 
sometimes  zinced.  Gralvanic  zincing  is  done  by  placing  the  metal  to  be 
galvanised  in  a  zinc  bath  filled  with  a  saturated  solution  of  sulphate  of  zinc. 

Zinc  is  also  used  to  form  important  alloys  ;  brass  consists  of  one  part  of 
zinc  and  one  of  copper,  and  german  silver  is  brass  to  which  some  nickel  has 
been  added.  Zinc  plates  are  extensively  used  as  the  oxidisable  plate  in  a 
great  many  forms  of  galvanic  batteries,  owing  to  its  solubility  in  dilute  acids, 
with  evolution  of  hydrogen. 

Zinc  is  not  absorbed  by  the  skin,  and  its  effects  on  the  organism  are 
limited  to  absorption  of  its  vapour,  through  inhalation,  or  inhalation  of 
the  dust.  Dust  is  created  in  large  quantities  in  the  grirding  of  the  oxide, 
and  precaution  should  be  taken  to  have  this  done  in  suitable  closed  chambei  s 
and  to  protect  the  workmen  by  respirators  when  they  are  obliged  to  enter 
the  grinding  chamber. 

Exposure  to  the  action  of  the  vapour  of  zinc  for  some  time  may  produce 
serious  symptoms  of  intoxication  :  cough  and  difficulty  of  breathing,  headache, 
giddiness,  stiffness  in  the  limbs,  sickness,  and  vomiting.  Copious  sweating 
sometimes  occurs. 

The  severe  colic  and  irritation  of  the  skin  which  is  sometimes  observed  in 
persons  exposed  to  the  action  of  zinc  dust,  &c.,  is  most  hkely  due  to  the  action 
of  impurities,  e.g.  lead  or  arsenic,  and  not  to  zinc.  But  the  powder,  acting 
merely  as  a  mechanical  irritant,  may  cause  considerable  cutaneous  irritation. 

Some  writers  consider  that  the  nervous  system  is  injuriously  affected  by 
exposure  to  the  action  of  zinc,  but  only  after  many  years,  the  reflex  and 
motor  systems  being  chiefly  affected.  It  has  undoubtedly  been  noticed  that 
farmyard  poultry  (especially  ducks)  have  been  affected  with  spasms  of  the 
legs  and  even  paralysis  when  ashes  from  a  zinc  furnace  had  been  left  in  their 
feeding  ground. 


■974  HYGIENE 

The  proper  condensation  of  the  vapour  is  the  great  desideratum,  and 
vigorous  ventilation  to  free  the  worlirooms  from  it. 

Those  engaged  in  the  wiring  of  champagne  bottles  with  '  galvanised '  wire 
have  been  observed  to  sufl'er  from  stomatitis,  inflammation  of  the  gums, 
sahvation,  fcetid  breath,  ulcers  of  the  gums  and  tonsils,  and  similar  symptoms 
have  been  noticed  among  coopers  using  zinced  iron  hoops.  It  appears  not  im- 
probable that  these  dangerous  symptoms  were  due  to  arsenic,  so  commonly 
present  in  commercial  zinc. 

It  is  important  that  the  vapour  and  dust  be  not  allowed  to  escape  from 
the  works  so  as  to  injure  the  vegetation  or  water-courses  in  the  neigh- 
bourhood, and  wash-water,  &c.,  from  the  works  should  not  be  admitted  into 
streams,  wells,  &c. 


SLAUGHTER-HOUSES 

AND 

THEIK     ADMINISTEATION 


BY 


E.  W.  HOPE,  M.D.,  D.Sc. 

ASSISTANT  MEDICAL  OFFICER  OF  HEALTH  FOR  THE  CITT  AND   PORT  OF  LIVERPOOL 
LECTURER   OX   PtTELIC    HEALTH   AT   UNIVERSITY   COLLEGE,   LIVERPOOL 


SLAUGHTER-HOUSES   AND    THEIR  ADMINISTRATION 

Among  the  many  industries  which  exercise  a  direct  or  indirect  effect  upon 
the  pubhc  health,  there  are  probably  none  of  greater  importance  than  those 
which  centre  in  the  meat  supply.  Little  need  be  said  in  support  of  the  need 
for  measures  to  ensure  that  meat  intended  for  consumption  as  food  shall  be 
good  and  wholesome  in  quality.  Apart,  however,  from  the  actual  quality  of 
the  meat,  and  the  processes  by  which  it  is  prepared  for  sale  and  consumption, 
we  have  also  to  deal  (a)  with  the  transport  and  storage  of  live-stock,  as  also 
with  the  preservation  of  imported  carcases,  (b)  with  the  keeping  of  animals, 
(c)  with  the  slaughtering  of  animals,  and  (d)  to  a  certain  extent  with  several 
important  branches  of  industry  in  which  animal  matters  or  substances  of 
animal  origin  are  dealt  with.  The  manner  in  which  this  variety  of  associated 
businesses  is  conducted  in  different  towns  and  districts  is  very  diverse  :  the 
general  principles  may  be  the  same,  but  local  custom,  expediency,  profit, 
or  convenience,  or  extent  of  supervision  lead  to  variations  in  detail  which 
exercise  a  great  influence  upon  the  general  aspect  of  the  business  and  its 
effects  upon  health. 

It  is  well  known  that  among  the  commonest  causes  of  '  nuisances,  or 
conditions  prejudicial  to  health,'  is  pollution  of  the  atmosphere,  which  not 
only  produces  bodily  discomfort,  but  tends  by  continuance  to  induce  an 
appreciable  impairment  of  health  and  strength.  A  large  abattoir,  or  even  a 
small  slaughter-house,  may  be  an  important  element  of  atmospheric  im- 
purity, and  the  more  dense  the  population  in  its  vicinity,  the  more  necessary 
it  becomes  to  mitigate  its  evils  by  careful  management ;  for  under  appropriate 
conditions  of  site,  structure,  and  management  the  business  may  be  so  carried 
on  as  to  cause  neither  offence  nor  injury  of  any  kind.  There  is  no  difficulty 
whatever  in  laying  down  the  general  principles  upon  which  appropriate  means 
of  preventing  or  minimising  nuisances  must  be  based,  but  in  dealing  with  any 
particular  establishment  it  is  often  a  matter  of  difficulty  'to  apply  these 
principles  to  the  best  advantage,  since  their  application  depends  upon  a  variety 
of  considerations,  an  important  one  frequently  being  original  defects  of  site 
and  structure,  arising  from  attempts  to  adapt  old  buildings,  not  originally  in- 
tended for  the  purpose,  to  the  requirements  of  slaughter-house,  lairage, 
or  other  offices  ;  this  often  implies  an  absence  of  conveniences  which  are 
necessary  not  only  to  facilitate  cleansing  but  to  prevent  defilement.  Or  the 
nuisance  may  be  dependent  upon  (1)  accumulation  of  filth  on  or  about  the 
premises,  or  on  its  removal  from  the  premises  in  an  offensive  condition  ;  (2)  on 
a  generally  filthy  condition  of  the  interior  of  the  buildings  and  the  premises 
and  utensils  generally  ;  (3)  on  an  improper  mode  of  disposing  of  offensive 
refuse,  liquid  or  otherwise,  and  carelessness  in  the  reception  of  offensive 
materials.  For  these  the  obvious  remedy  is  a  supervision  that  will  ensure 
cleanliness  in  the  broadest  sense  of  the  term,  and  a  close  observance  of  care- 
fully drawn  bye-laws  which  bear  upon  the  subject. 

The  importation  and  transport  of  cattle  are  regulated  by  orders  of  the  Privy 
Council  under  the  Contagious  Diseases  (Animals)  Acts.     An  order  under  this 

VOL.  I,  3  R 


978  HYGIENE 

Act  provides  for  landing-places  for  such  foreign  animals  as  are  subject  to 
slaughter  ;  it  also  defines  quarantine  stations  for  animals  not  subject  to 
immediate  slaughter,  and  also  specifies  landing-places  for  foreign  animals 
which  are  permitted  to  travel, being  subject  neither  to  quarantine  nor  slaughter. 
Most  of  the  livestock  imported  from  or  through  the  United  States  is  landed 
at  Liverpool  (Woodside),  and  as  these  cattle  are  not  permitted  to  travel,  they 
are  slaughtered  on  landing,  the  carcases  being  forwarded  to  their  destination. 
Canadian  cattle  are  subject  to  a  short  detention  or  '  quarantine,'  and  to  an 
examination  by  an  inspector  appointed  by  the  Privy  Council,  upon  whose  re- 
sponsibihty  they  are  passed  on.  No  restrictions  of  these  lands  are  placed 
upon  the  moving  of  animals  within  the  United  Kingdom,  but  the  Contagious 
Diseases  (Animals)  Acts  contain  pro%isions  restricting  the  movement  of 
cattle  within  infected  areas  and  under  certain  conditions,  and  these  Acts 
require  all  railway  trucks,  lairages,  pens,  &c.,  used  in  the  transport  or  tem- 
porary accommodation  of  cattle  to  be  lime-washed  and  purified,  before  twelve 
o'clock  on  the  day  following  their  use,  or  before  they  are  again  used  for  any 
purpose. 

As  evidence  of  the  large  import  trade  it  may  be  mentioned  that  close  on 
400,000  cattle,  383,000  sheep,  and  156,000  swine  are  landed  annually  at  the 
port  of  Liverpool  alone,  besides  163,000  tons  of  fresh  and  preserved  meat. 

The  following  extracts  from  the  Animals  Order  regulating  disinfection 
of  vessels  and  transit  by  water  are  important : — 

Vessels 

100.—  (1)  A  vessel  usee!  for  carrying  animals  by  sea,  or  on  a  canal,  river,  or  inland 
navigation,  shall,  after  the  landing  of  animals  therefrom,  and  before  the  taking  on  board 
of  any  other  animal  or  other  cargo,  be  cleansed  and  disinfected  as  follows  : 

(i)  All  parts  of  the  vessel  with  which  animals  or  their  droppings  have  come  in  contact 
shall  be  scraped  and  swept :  then 

(ii)  The  same  parts  of  the  vessel  shall  be  thoroughly  washed  or  scrubbed  or  scoured 
with  water :  then 

(iii)  The  same  parts  of  the  vessel  shall  have  applied  to  them  a  coating  of  lime-wash  : 
except  that 

(iv)  The  application  of  lime-wash  shall  not  be  compulsory  as  regards  such  parts  of  the 
vessel  as  are  used  for  passengers  or  crew. 

(2)  The  scrapings  and  sweepings  of  the  vessel  shall  not  be  landed  unless  and  until 
they  have  been  well  mixed  with  quicklime. 

(3)  Except  that  in  the  case  of  a  ferry-boat  or  other  vessel  which  makes  short  and 
frequent  passages  across  a  river  or  an  arm  of  the  sea  or  other  water,  it  shall  be  sufficient 
if  the  ferry-boat  or  vessel  be  cleansed  and  disinfected  once  in  every  period  of  twelve  hours 
within  which  it  is  so  used. 

Fodder  and  Litter 

101. — (1)  All  partly  consumed  or  broken  fodder  that  has  been  supplied  to,  and  all 
litter  that  has  been  used  for  or  about,  animals  carried  by  sea,  or  on  a  canal,  river,  or 
inland  navigation,  shall,  when  landed  from  the  vessel,  be  forthwith  well  mixed  with  quick- 
lime and  be  effectually  removed  from  contact  with  animals. 

(2)  Nothing  in  this  Article  shall  apply  to  fodder  or  litter  supplied  to  or  used  for  or 
about  foreign  animals. 

Movable  Gangways  and  other  Apparatus 

102.— (1)  A  movable  gangway  or  passage-way,  cage,  or  other  apparatus,  used  or 
intended  for  the  loading  or  unloading  of  animals  on  or  from  a  vessel,  or  otherwise  used  in 
connection  with  the  transit  of  animals  by  sea,  or  on  a  canal,  river,  or  inland  navigation, 
shall,  as  soon  as  practicable  after  being  so  used,  be  cleansed  as  follows : 

(i)  The  gangway  or  apparatus  shall  be  scraped  and  swept,  and  all  dung,  litter,  and  other 
matter  shall  be  effectually  removed  therefrom  :  then 

(ii)  The  gangway  or  apparatus  shall  be  thoroughly  washed  or  scrubbed  or  scoured  with 
water. 

(2)  The  scrapings  and  sweepings  of  the  gangway  or  apparatus,  and  all  dung,  litter,  and 


SLAUGHTER-HOUSES  AND   THEIR  ADMINISTRATION    979 

■other  matter  removed  therefrom  shall  forthwith  be  well  mixed  with  quicklime,  and  be 
leifectually  removed  from  contact  with  animals. 

Landing  Places 

110. — (1)  Where  an  animal  at  a  place  of  landing  or  place  adjacent  thereto  is  affected 
•with  disease,  that  place  and  every  other  place  where  the  animal  is  or  since  landing  has 
lieen  shall  not  be  used  for  any  animals  other  than  animals  brought  thereto  with  that 
animal  (in  the  same  vessel  or  otherwise)  unless  and  until  the  place  has  been,  as  far  as 
■practicable,  cleansed  and  disinfected. 

(2)  Nothing  in  this  chapter  shall  apply  to  a  Foreign  Animals  Wharf,  nor  to  a  Foreign 
.Animals  Quarantine  Station,  nor  to  a  landing-place  for  foreign  animals. 

Offences 

172. — (1)  If  the  slaughter  of  animals  is  not  commenced  at  the  time  directed  by  the 
Privy  Council  under  this  part,  or  completed  in  accordance  with  the  provisions  of  this  part, 
the  person  failing  to  cause  such  slaughter  to  be  so  commenced  or  completed  shall  be 
■deemed  guilty  of  an  offence  against  the  Act  of  1878. 

(2)  If  any  dung  of  animals,  or  any  fodder,  litter,  utensils,  pens,  hurdles,  fittings,  or 
■  other  thing  is  landed  or  removed  in  contravention  of  this  part,  the  owner  thereof,  and  the 
owner  and  the  lessee  and  the  occupier  of  the  place  of  landing  or  other  place  where  or  from 
which  such  dung  or  other  thing  is  landed  or  removed,  and  also  in  the  case  of  the  landing 
^thereof,  the  owner  and  the  character  and  the  master  of  the  vessel  from  which  the  same  is 
landed,  shall,  each  according  to  and  in  respect  of  his  own  acts  or  defaults,  be  deemed 
guilty  of  an  offence  against  the  Act  of  1878. 

Fittings  of  Vessels 
116. — (1)  Every  place  used  for  animals  on  board  a  vessel  shall  be  divided  into  pens  by 
substantial  divisions. 

(2)  Each  pen  shall  not  exceed  nine  feet  in  breadth  or  fifteen  feet  in  length. 

(3)  The  floor  of  each  pen  shall,  in  order  to  prevent  slipping,  be  strewn  with  a  proper 
^quantity  of  litter  or  sand  or  other  proper  substance,  or  be  fitted  with  battens  or  other 
proper  footholds. 

(4)  Every  such  place,  if  enclosed,  shall  be  ventilated  by  means  of  separate  inlet  and 
-outlet  openings,  of  such  size  and  position  as  will  secure  a  proper  supply  of  air  to  the  place 
in  all  states  of  weather. 

Overcrowding 
117. — A  vessel  bringing  animals  to  any  port  or  place  in  England  or  Wales  or  Scotland 
from  any  port  or  place  in  the  United  Kingdom  shall  not  be  overcrowded  so  as  to  cause 
.unnecessary  suffering  to  the  animals  on  board. 

Shorn  Sheep 
118. — Between  each  1st  day  of  November  and  the  next  following  30th  day  of  April 
.(both  days  inclusive)  shorn  sheep  shall  not  be  carried  on  the  deck  of  a  vessel,  except 
where  they  were  last  shorn  more  than  sixty  days  before  being  so  carried. 

Gangivays  for  Sheep-Pens 
119. — Where  sheep  are  carried  on  the  deck  of  a  vessel,  proper  gangways  shall  be  pro- 
-yided  either  between  or  above  the  pens  in  which  they  are  carried. 

Detention 
120. — Animals  landed  from  a  vessel  shall,  on  a  certificate  of  an  Inspector  of  the  Privy 
Council,  certifying  to  the  effect  that  the  provisions  of  this  chapter,  or  some  or  one  of 
them,  have  not  or  has  not  been  observed  in  the  vessel,  be  detained,  at  the  plaoe  of  land- 
ing, or  in  lairs  adjacent  thereto,  until  the  Privy  Council  otherwise  direct. 

Shipping  and  Unshipping  Places 

Water 

121. — At  every  place  where  animals  are  put  on  board  of  or  landed  from  vessels,  pro- 

■vision  shall  be  made,  to  the  satisfaction  of  the  Privy  Council,  for  a  supply  of  water  for 

animals ;  and  water  shall  be  supplied  there,  gratuitously,  on  request  of  any  person  having 

charge  of  any  animal. 

Food 
122. — At  every  place  where  animals  are  landed  from  vessels,  provision  shall  be  made, 
to  the  satisfaction  of  the  Privy  Council,  for  the  speedy  and  convenient  unshipment  of 

3b2 


980  HYGIENE 

animals  and  for  a  supply  of  food  for  them  ;  and  food  shall  be  supplied  there,  on  request, 
of  any  person  having  charge  of  any  animal,  at  such  price  as  the  Privy  Council  from  time- 
to  time  approve. 

Landing  and  Treatment  of  Dung,  Fodder,  d;c.,  of  Animals  winch  are  intended  to  be 
landed  at  a  Foreign  Animals  ^V^Mrf 

164. — (1)  No  dung  of  foreign  animals  that  have  been  or  are  intended  to  be  landed  at  a 
Foreign  Animals  Wharf,  and  no  partly  consumed  or  broken  fodder  that  has  been  supplied 
to  such  animals,  and  no  litter  that  has  been  used  for  or  about  such  animals,  shall  be 
landed  without  the  previous  consent  in  writing  of  the  Local  Authority  of  the  place  where 
it  is  intended  to  land  such  dung  or  other  thing. 

(2)  All  such  dung  and  all  such  partly  consumed  or  broken  fodder  and  all  such  litter 
shall,  when  so  landed,  be  forthwith  well  mixed  with  quicklime  and  be  effectually  removed 
fi'om  contact  wrth  animals. 

Offences 

126. — If  anything  is  done  or  omitted  to  be  done  in  contravention  of  any  of  the  fore- 
going provisions  of  this  part,  the  owner  and  the  charterer  and  the  master  of  the  vessel  in 
which — and  the  owner  and  the  lessee  and  the  occupier  of  the  place  where  animals  are  put 
on  board  of  or  landed  from  vessels  at  which — and  the  railway  company  carrying  animals 
on  or  owning  or  working  the  railway  on  which — and  also,  in  case  of  the  overcrowding  of 
a  vessel,  or  of  a  railway  truck,  horse-box,  or  other  vehicle  on  a  railway,  or  of  the  carrying: 
on  a  railway  of  sheep  shorn  and  unclothed,  the  consignor  of  the  animals  in  respect  of 
which  (as  the  case  may  be) — the  same  is  done  or  omitted,  shall  each,  according  to  and 
in  respect  of  his  or  their  own  acts  or  omissions,  be  deemed  guilty  of  an  offence 
against  the  Act  of  1878. 

In  regard  to  the  storage  of  livestock,  it  is  evident  that  animals  sent  to- 
a  slaughter-house  are  not,  under  ordinary  circumstances,  detained  there  for 
any  lengthened  period ;  nevertheless,  as  soon  as  one  batch  is  slaughtered 
another  set  replaces  the  first,  and  the  result,  so  far  as  the  keeping  of  animals, 
is  concerned,  is  precisely  the  same  as  would  be  the  case  were  a  number  kept 
permanently  upon  the  premises.  The  Public  Health  Act,  the  Nuisances 
Kemoval  Act,  and  local  Acts  generally  recognise  the  fact  that  animals  may 
be  so  kept  as  to  be  a  nuisance  injurious  to  health,  and  the  necessity  for  the 
regulation  and  control  of  the  keeping  of  livestock — more  especially  where 
human  population  is  aggregated— is  sufficiently  obvious. 

The  nuisances  arise  from  defects  in  structure  of  the  lairages,  from  in- 
sufficient space,  from  defective  drainage  and  water  supply,  and  accumulations 
of  filth  and  the  like.  Soakage  of  putrefying  animal  matters  through  badly 
paved  floors  is  one  of  the  means  of  pollution  of  soil  and  contamination  of 
wells,  streams,  &c.  Defective  ventilation  is  perhaps  the  evil  most  commonly 
met  with  in  places  where  animals — more  especially  dairy  cows — are  kept  in 
towns,  and  the  results  are  very  serious.  Stall-fed  dairy  cows  are  exceedingly 
prone  to  tubercle,  and  it  is  not  improbable  that  30  or  40  per  cent,  of  all  dairy 
cows  kept  in  towns  are  affected  by  it.  Confinement,  bad  air,  and  the  drain 
of  constant  milking  are  doubtless  the  predisposing  causes. 

The  remedies  for  the  harmful  conditions  arishig  from  the  keeping  of 
animals  are  to  be  sought  in  the  proper  construction  of  the  sheds,  cleanly 
management,  and  proper  storage  of  food,  &c.  These  points  will  be  referred 
to  in  connection  with  the  lairages  of  pubHc  abattoirs.  We  turn  meantime  to 
the  slaughtering  of  animals. 

Slaughter-houses,  be  they  public  or  private,  large  or  small,  require  to  be 
specially  constructed  to  meet  the  necessities  of  the  trade  carried  on  within 
them.  Of  equal  importance  is  it  that  their  site  in  regard  to  inhabited 
dwelhngs  should  be  carefully  chosen.  It  is  instructive  to  read  the  accounts 
of  medical  officers  of  health,  both  metropolitan  and  provincial,  of  conditions 
which  existed  some  few  years  back  in  some  of  the  slaughter-houses  of  their 


SLAUGHTEB-HOUSES  AND   THE  IB  ADMINISTBATION    981 

respective  districts.     It  appears  that  in  one  important  and  populous  metro- 
politan locality  there  were  twenty-four  slaughter-houses,  which,  with  one 
■or  two  exceptions,  were  situated  side  by  side.     *  All  of  them,'  we  read,  '  have 
a  direct  communication  with  a  shop  facing  the  street,  and  six  of  them  have 
no  other  means  for  the  entrance  of  cattle  than  by  their  passing  across  the 
public  footways  and  through  the  shops,  which  are  low  and  narrow.'     They 
appear  to  have  been  separated  from  one  another  mostly  by  dwarf  partitions  ; 
and  from  the  lairs,  which  are  often  employed  as  hanging  sheds  for  the  meat,  by 
like  partitions  of  wood.     When  reported  on  they  were  described  as  being  '  in 
a  state  of  general  disrepair ;  the  roofs  dilapidated,  the  flooring  uneven  and 
broken,  the  side  walls  filthy  and  blood-stained,  the  drainage  defective  and 
•sluggish,  the  water  supply  inadequate  and  badly  placed.     Accumulations  of 
dung,  offal,  and  blood  were  general,  and  liquid  manure  was  allowed  to  run 
freely  into  the  sewers.'     Clearly  such  premises  as  these  cannot  be  other 
than  prejudicial  to  health,  and  the  question  is  whether  entire  reconstruction 
or  removal  altogether  from  the  district  would  be  the  more  efficient  remedy. 
Again,  we  learn  from  a  report  upon  another  urban  district  that  slaughtering 
is  (or  was)  'carried  on  in  shops,  lairs,  stables,  cellars,  inhabited  dwelling 
rooms  and  passages,  as  well  as  in   open  yards   and   on   door   steps  ;  the 
slaughtering  places,  moreover,  being  in  a  majority  of  instances  closely  con- 
tiguous to  the  residence  of  the  butchers,  and  generally  approached  through 
the  shop.     Most  of  the  slaughter-houses  are  not  open  to  the  roof,  living  or 
bed  rooms  being  situated  over  them,  there  being,  moreover,  in  a  large  pro- 
portion of  them,  direct  communication  with  the  inhabited  portions  of  the 
premises.     Many  of  the  slaughter-houses  are  absurdly  small ;  the  ventilation 
is  generally  described  as  deficient,  bad,  very  bad,  or  "  none,"  while  m  a  con- 
;siderable  number  there  is  no  water  supply  within  the  slaughter-house.'     It 
need  hardly  be  added  to  complete  this  astonishing  picture  that  lairage  is, 
as  a  rule,  conspicuous  by  its  absence,  and  that,  where  provided,  it  is  of  the 
most  inadequate  description,  whether  regard  be  had  to  the  dimensions  or 
position,  or  to  the  relations   of  the   lairs  to  other  parts  of  the  premises. 
Another  account  is  given,  '  where  sheep  and  oxen  are  slaughtered   in  the 
shop  forming  part  of  the  dwelling-house,  it  is  customary  to  see  a  blood-hole, 
about  two  feet  square  and  eighteen  to  twenty-four  inches  deep,  in  the  middle 
of  the  shop  fioor.     In  this  at  the  time  of  slaughtering  the  blood  is  collected, 
and  the  practice  is  to  throw  in  sawdust,  with  the  object  of  sopping  up  the 
"blood,  so  as  to  permit  of  the  blood  being  readily  removed  the  following 
morning  by  the  public  scavenger.     Most  of  the  blood-holes,  however,  when 
inspected,  had  not  been  thoroughly  emptied  and  cleansed,  enough  blood 
having  been  left  at  the  bottom  and  corners  to  give  rise  to  putrid  emanations, 
whilst  the  effluvia  from  animals  pounded  within  the  house  difi"used  them- 
selves throughout  it.'     These  of  course  are  accounts  of  conditions  existing  in 
vslaughter-houses  a  few  years  back,  and  it  may  be  said  that  they  do  not  apply 
exactly  to  existing  conditions  ;  however,  an  approximation  to  the  state  of 
;affairs  described  is  by  no  means  a  rarity,  while  there  can  be  no  question 
that  plenty  of  examples  of  slaughter-houses,  private,  semi-private,  or  even 
public,  are  to  be  met  with,  which  in  site,  structure,  and  in  every  particular, 
are  unsuited  to  their  purpose,  and  in  no  respect  are  conducted  as  they  should 
be.     Furthermore,  it  is  important  to  note  that  it  has  been  due  to  pressure 
-from  without  that  these  revolting  details  have  been  modified,  rather  than  to 
:any  effort  on  the  part  of  those  engaged  in  the  trade  to  improve  its  conduct, 
accommodation  of  the  most  meagre  description  with  a  minimum  of  atten- 
tion satisfying  the  very  modest  requirements  of  many  butchers.     We  learu 
:an  important  lesson  here. 


982  HYGIENE 

It  will  be  observed  that  the  least  satisfactory  conditions  have  been,  and 
still  are,  associated  with  jjr/raic  slaughter-houses,  for  such  an  aggregation  as 
has  been  previously  described  is  not  to  be  regarded  as  a  public  abattoir.  We 
shall  presently  refer  to  public  abattoirs  and  to  the  advantages  which  they 
present,  and  in  the  meantime  deal  with  private  slaughter-houses. 

In  most  towns  the  proprietors  of  small  slaughter-houses  are  licensed  for 
a  retail  business  only ;  i.e.  the  licensee  is  permitted  to  slaughter  only  those 
animals  of  which  he  disposes  in  the  course  of  his  ordinary  business.  A 
wholesale  licence  enables  him  to  slaughter  for  other  butchers,  and  to  permit 
otber  butchers  to  slaugbter  on  his  premises.  In  both  of  these  instances  the 
places  of  business  are  private.  At  the  present  time  almost  every  sanitary 
authority  has  adopted  bye-laws  for  the  control  and  management  of  these 
places.  The  bye-laws  of  various  districts  have  a  more  or  less  close  resem- 
blance to  one  another,  particulars  and  details  being  modified  by  local  customs. 
Among  the  oldest  and  best  are  those  of  Liverpool,  made  in  1849,  and  acted 
upon  since  that  time.  They  are  almost  identical  with  the  Model  Bye-laws 
of  the  Local  Government  Board,  and  may  be  taken  as  the  type  in  common 
use.  They  embrace  regulations  for  registering  and  inspection  of  slaughter- 
houses, and  for  keeping  the  same  in  a  cleanly  and  proper  state,  and  for  re- 
moving filth  therefrom  at  least  once  in  every  twenty-four  hours,  and  for 
requiring  that  they  should  be  provided  by  the  occupier  with  a  sufficient 
supply  of  water. 

FIRST 

The  Occupier  of  any  Slaughter-house,  who  shall  at  any  time  after  the  date  of  the 
cex-tificate  at  the  foot  of  his  licence,  and  without  the  assent  in  wi'iting  of  the  Borough 
Engineer,  Medical  Officer  of  Health,  or  Building  Surveyor  for  the  time  being,  make  any 
change  or  alteration  whatsoever,  or  permit  or  suffer  any  change  or  alteration  whatsoever 
to  be  made  in  the  Slaughter-house  or  Building  to  which  such  hcence  applies  in  respect  ol 
the  drainage  of  the  same  ; 

Or 

In  respect  of  the  flagging  or  paving  of  the  same  ; 

Or 

In  respect  of  the  ventilation  of  the  same ; 

Or 

In  respect  of  the  supply  of  water  to  the  same  ; 
Shall,  for  each  and  every  such  offence,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and 
the  sum  of  Five  Shillings  for  each  and  every  day,  after  the  first,  during  which  such  change 
or  alteration  shall  be  continued  and  unremedied. 

SECOND 

The  Occupier  of  any  Slaughter-house  who  shall  neglect  or  omit  to  cause  the  same  to  be 
thoroughly  whitewashed  with  quicklinae  to  the  satisfaction  of  the  Medical  Officer  of  Health 
for  the  time  being,  at  least  once  during  the  first  ten  days  of  each  and  every  month,  shall, 
for  such  neglect  or  omission,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and  the  sum  of 
Five  Shillings  for  each  and  every  day,  after  the  first,  during  which  such  neglect  and 
omission  shall  continue. 

THIRD 

The  Occupier  of  any  Slaughter-house  who  shall  erect,  build,  or  construct,  or  who  shall 
permit  or  suffer  to  be  erected,  built,  or  constructed,  or  who  shall  permit  or  suffer  to  be, 
remain,  or  continue,  within  any  Slaughter-house,  any  privy,  middenstead,  or  cesspool,  or 
any  opening,  access,  or  communication  from  such  Slaughter-house  to  any  such  privy, 
middenstead,  or  cesspool,  shall,  for  each  and  every  such  offence,  forfeit  and  pay  the  sum 
of  Forty  Shillings,  and  the  sum  of  Five  Shillings  for  each  and  every  day,  after  the  first, 
during  which  such  privy,  middenstead,  or  cesspool  shall  be,  remain,  or  continue,  within 
such  Slaughter-house,  or  during  which  any  such  opening,  access,  or  communication  shall 
be,  remain,  or  continue,  from  such  Slaughter-house  to  such  privy,  middenstead,  or  cesspool. 

rOUETH 

The  Occupier  of  any  Slaughter-house  who  shall  keep,  or  feed,  or  permit  or  suffer  to  be- 
kept  or  fed,  within  such  Slaughter-house,  any  swine,  fowls,  or  other  animals  whatsoever,. 


SLAUGHTEB-HOUSES  AND   THEIR  ADMINISTBATION    983 

used  for  human  food,  save  and  except  such  cattle  as  shall  from  time  to  time  be  brought 
to  such  Slaughter-house  for  the  purpose  of  being  there  slaughtered,  shall,  for  every  such 
offence,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and  the  sum  of  Fwe  Shillings  for 
each  and  every  day,  after  the  first,  during  v/hich  such  sv/ine,  fowl,  or  other  animal  shall 
remain  and  continue  in  such  Slaughter-house. 


The  Occupier  of  any  Slaughter-house  who  shall  keep  or  retain,  or  permit  or  suffer  to  be 
kept  or  retained  therein,  any  cattle  for  a  longer  period  of  time  than  seventy-two  hours 
previous  to  the  slaughtering  of  the  same,  shall,  for  each  and  every  such  offence,  forfeit 
and  pay  the  sum  of  Forty  Shilli/ngs. 

SIXTH 

The  Occupier  of  any  Slaughter-house  who  shall  neglect  or  omit  to  cause  the  same  to  be 
thoroughly  washed  and  cleansed  within  three  hours  after  the  completion  of  the  slaughter- 
ing and  dressing  of  any  cattle  therein,  on  any  day  during  which  any  such  slaughtering  or 
dressing  shall  take  place,  shall,  for  each  and  every  such  offence,  forfeit  and  pay  the  sum 
of  Forty  Shillings. 

SEVENTH 

Every  Occupier  of  a  Slaughter-house  shall  provide,  keep,  and  from  time  to  time  main- 
tain a  sufficient  number  of  tubs,  boxes,  or  vessels,  with  tight  or  close-fitting  covers  thereto, 
constructed  to  the  satisfaction  of  the  engineer  for  the  time  being,  for  the  purpose  of  re- 
ceiving and  conveying  away  from  such  Slaughter-house  all  manure,  garbage,  offal,  and 
filth ;  and  shall,  immediately  after  the  killing  and  dressing  of  any  cattle  in  such  Slaughter- 
house, cause  all  such  manure,  garbage,  offal,  and  filth  to  be  placed  in  such  tubs,  boxes,  or 
vessels,  and  to  be  removed  beyond  the  limits  of  the  Borough  of  Liverpool,  at  least  once 
during  every  day,  to  the  satisfaction  of  the  Medical  Officer  of  Health  for  the  time  being ; 
and  any  Occupier  of  a  Slaughter-house  who  shall  neglect  or  omit  to  provide,  keep,  or 
from  time  to  time  to  maintain  such  number  of  such  tubs,  boxes,  or  vessels  ; 
Or 
Who  shall  neglect  or  omit  to  cause  such  manure,  garbage,  offal,  and  filth  to  be 
placed  therein  and  removed  in  the  manner,  at  the  times,  and  beyond  the  limits 
aforesaid ; 
Or 
Who  shall  neglect  or  omit  to  cause  such  tubs,  boxes,  or  vessels,  after  being  used  for 
the  purpose  of  such  removal,  to  be  thoroughly  cleansed  and  purified  before  the 
same  are  again  brought  within  the  limits  of  the  said  Borough, 
Shall,  for  each  and  every  such  offence,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and 
the  sum  of  Five  Shillings  for  each  and  every  day,  after  the  first,  during  which  such  neglect 
or  omission  shall  continue. 

EIGHTH 

The  occupier  of  any  Slaughter-house  who  shall  slaughter,  or  permit  or  suffer  to  be 
slaughtered  therein,  any  diseased  or  unsound  cattle,  shall,  for  each  and  every  such  offence, 
forfeit  and  pay  the  sum  of  Forty  Shillings. 


The  occupier  of  any  Slaughter-house  who  shall,  in  case  of  any  diseased  or  unsound 
cattle  being  brought  to  his  or  her  Slaughter-house,  neglect  or  omit  forthwith  to  give  infor- 
mation to  the  Inspector  of  Nuisances,  at  his  Office,  in  the  Public  Offices,  Cornwallis  Street, 
in  the  said  Borough  of  Liverpool,  of  such  diseased  or  unsound  cattle  having  been  so 
brought  to  such  Slaughter-house,  shall,  for  every  such  neglect  or  omission,  forfeit  and  pay 
the  sum  of  Forty  Shillings. 

TENTH 

The  Occupier  of  any  Slaughter-house  who  shall  neglect  or  omit  to  remove,  or  cause  to 
be  removed  from  such  Slaughter-house,  the  blood,  hides,  and  skins  of  any  cattle  that 
shall  be  slaughtered  in  such  Slaughter-house,  within  two  days  next  after  such  cattle  shall 
have  been  slaughtered,  shall,  for  every  such  neglect  or  omission,  forfeit  and  pay  the  sum 
of  Forty  Shillings,  and  the  sum  of  Five  Shillings  for  each  and  every  day,  after  the  first, 
during  which  such  neglect  or  omission  shall  continue. 

ELEVENTH 

The  Occupier  of  every  Slaughter-house  shall  keep,  or  cause  to  be  kept  therein,  a  book, 
in  which  shall  be  entered  the  number  and  description  of  all  cattle  slaughtered  therein, 
together  with  the  name  and  address  of  the  owner  of  such  cattle,  or  of  the  person  bringing 


984  HYGIENE 

such  cattle  to  the  said  Slaughter-house ;  and  shall,  on  Monday  in  each  and  every  week, 
deliver  or  transmit  to  the  Inspector  of  Nuisances  for  the  time  being,  at  his  said  office,  a 
correct  transcript  copy  or  duplicate,  signed  by  him,  of  all  entries  made  in  such  book  during 
the  preceding  week,  and  shall,  at  any  and  all  times,  on  being  requested  so  to  do  by  the 
said  Inspector  of  Nuisances,  or  any  other  officer  of  the  said  Council  thereto  authorised  by 
the  said  Council,  produce  and  show  to  the  said  Inspector,  or  other  officer,  the  said  book ; 
and  any  occupier  of  a  Slaughter-house  who  shall  neglect  or  omit- 
To  keep,  or  cause  to  be  kept,  such  book ; 
Or 

To  enter,  or  cause  to  be  entered  therein,  the  number  and  description  of  any  cattle 
slaughtered  in  such  Slaughter-house,  or  the  name  or  address  of  the  owner  of  such 
cattle,  or  of  the  person  bringing  such  cattle  to  the  said  Slaughter-house ; 
Or 

To  deliver  or  transmit  such  transcript  copy  or  duplicate  in  manner  and  at  the  times 
aforesaid, 
Or 

To  produce  and  show  such  book  to  the  persons,  at  the  times  and  in  manner  afore- 
said, 
Shall,  for  every  such  neglect  or  omission,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and 
the  sum  of  Five  Shillings  for  each  and  every  day,  after  the  first,  during  which  such 
neglect  or  omission  shall  continue.  And  any  person  who  shall  make,  or  cause,  or  procure, 
or  permit  to  be  made  any  false  entry  in  such  book,  or  in  such  transcript  copy  or  duplicate, 
concerning  any  of  the  matters  or  things  hereby  required  to  be  entered  or  stated  in  such 
book  or  in  such  transcript  copy  or  duplicate,  shall,  for  each  and  every  such  offence, 
forfeit  and  pay  the  sum  of  Forty  Shillings. 

TWELFTH 

Every  Occupier  of  a  Slaughter-house  shall,  on  request  by  the  Borough  Engineer, 
Medical  Officer  of  Health,  or  other  authorised  Officer  of  the  said  Council  for  the  time 
being,  forthwith  cause  all  repairs  in  or  concerning  such  Slaughter-house  which  he  shall 
be  required,  by  such  request  as  aforesaid,  to  perform,  to  be  done  and  executed  to  the 
satisfaction  of  the  Borough  Engineer,  Medical  Officer  of  Health,  or  other  authorised 
Officer  of  the  said  Council  for  the  time  being ;  and  any  Occupier  of  a  Slaughter-house 
who  shall,  for  the  space  of  one  week  after  such  request  as  aforesaid,  refuse  or  neglect  to 
cause  such  repairs  to  be  so  done  and  executed  as  aforesaid,  shall,  for  such  refusal  or 
neglect,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and  the  sum  of  Five  Shillings  for 
each  and  every  day,  after  the  first,  during  which  such  refusal  or  neglect  shall  continue. 

THIETEENTH 

Any  Occupier  of  a  Slaughter-house  who  shall  keep,  or  permit,  or  suffer  to  be  kept, 
within  such  Slaughter-house,  any  dog,'  without  the  same  being  well  and  sufficiently 
chained,  fastened,  and  secured,  shall,  for  every  such  offence,  forfeit  and  pay  the  sum  of 
Forty  Shillings,  and  the  sum  of  Five  Shillings  for  each  and  every  day,  after  the  first,  during 
which  such  dog  shall  be  so  kept. 

FOURTEENTH 

The  Occupier  of  every  licensed  or  registered  Slaughter-house  shall  cause  the  word 
'  Slaughter-house,' together  with  the  number  corresponding  with  the  number  of  his  licence 
or  register,  as  the  occupier  of  such  Slaughter-house,  as  the  same  shall  from  time  to  time 
appear  on  the  register  of  such  licences,  kept  under  the  directions  of  the  said  Council,  to 
be  painted  or  otherwise  inscribed,  to  the  satisfaction  of  the  Inspector  of  Nuisances  for  the 
time  being,  on,  over,  or  adjoining  to  the  outside  of  the  door  or  entrances  to  such  Slaughter- 
house, and  kept  and  continued  there  not  obliterated  or  defaced ;  and  any  Occupier  of  a 


'  '  A  dog  harbours  a  tsenia,  and  this  parts  with  its  last  joint  (proglottis)  containing  ripe 
eggs,  or  departs  in  person  from  the  intestine.  The  proglottis  or  tffinia  may  fall  to  the 
ground  entire,  \vith  all  the  eggs  in  it,  or  the  eggs  may  be  laid  by  the  proglottis  already  in 
the  intestinal  canal,  and  leave  it  in  separate  clusters  mixed  with  faces.  These  are  now 
eaten  by  cattle  or  man  wth  their  respective  raw  or  uncooked  food.  Arrived  in  the  intestine, 
they  are  developed  into  embryos,  which  penetrate  into  the  organs  of  the  abdominal  cavity 
and  the  chest,  and  are  there  developed  into  the  cystic  forms  of  echinococci.'  '  The  echino- 
cocci  of  cattle,  particularly  of  sheep,  are  set  free  in  the  process  of  slaughtering  ;  these  are 
thrown  on  the  ground  and  devoured  by  dogs,  in  them  again  to  grow  into  ripe  tienia.' 
(Dr.  Thudichum  on  '  Parasitic  Diseases  of  Quadrupeds  used  for  Food  by  Man,'  in  the 
Seventh  Report  of  the  Medical  Officer  of  the  Frivy  Council.) 


SLAUGHTEB-HOUSES  AND    THEIR  ADMINISTBATION   98/> 

Slaughter-house  who  shall  neglect  or  omit  so  to  do  shall,  for  each  neglect  or  omission, 
forfeit  and  pay  the  sum  of  Forty  Shillings,  and  the  further  sum  of  Five  Shillings  for 
each  and  every  day,  after  the  first,  during  which  such  neglect  or  omission  shall  continue. 

FIFTEENTH 

The  Occupier  of  every  Slaughter-houae  shall  cause  a  copy  of  these  Bye-Laws,  written 
•or  printed  in  large  characters,  to  be  affixed  in  some  conspicuous  place  in  such  Slaughter- 
house, to  the  satisfaction  of  the  Inspector  of  Nuisances  for  the  time  being,  and  to  be  at  all 
times  kept  and  continued  there  not  obliterated  or  defaced.  And  any  occupier  of  a 
Slaughter-house  who  shall  neglect  or  omit  to  cause  such  copy  to  be  so  affixed,  kept,  and 
continued,  shall,  for  such  offence,  forfeit  and  pay  the  sum  of  Forty  Shillings,  and  the 
sum  of  Five  Shillings  for  each  and  every  day,  after  the  first,  during  which  such  neglect  or 
•omission  shall  continue. 

The  following  is  the  form  of  licence  held  by  the  proprietors  of  the  few 
private  slaughter-houses  allowed  within  the  city  of  Liverpool,  and  it  may  be 
taken  as  the  standard  form  employed  throughout  the  country.  No  licence 
has  been  granted  in  Liverpool  since  1877 : — 

City  of  Liverpool,  to  wit. 

Wheeeas,  by  an  Act  passed  in  the  Session  of  Parliament  held  in  the  ninth  and  tenth 
years  of  the  reign  of  her  Majesty  Queen  Victoria,  intituled  'An  Act  for  the  Improvement 
•of  the  Sewerage  and  Drainage  of  the  Borough  of  Liverpool,  and  for  making  further  Pro- 
visions for  the  Sanitary  Eegulation  of  the  said  Borough,'  it  was,  amongst  other  things, 
enacted,  that  any  person  who  should,  within  the  Parish  of  Liverpool,  kill  or  dress,  for  the 
purpose  of  trade,  or  cause  or  permit  to  be  killed  or  dressed  for  such  purpose,  any  Cattle, 
elsewhere  than  in  certain  Slaughter-houses  erected  as  therein  mentioned  under  the 
powers  and  authorities  of  a  certain  Act  passed  in  the  twenty-sixth  year  of  the  reign  of  his 
late  Majesty  King  George  the  Third,  or  in  a  place  erected  or  used  for  a  Slaughter-house, 
under  a  licence  for  that  purpose,  granted  by  the  Council  of  the  said  City,  under  the 
authority  of  a  certain  Act  therein  recited,  for  the  Improvement,  good  Government,  and 
Police  Eegulation  of  the  City  of  Liverpool,  and  in  force  at  the  time  of  the  killing  or  dress- 
ing of  such  Cattle,  should,  for  every  such  offence,  forfeit  and  pay  a  sum  not  exceeding 
Five  Pounds,  and  the  like  penalty  for  every  day  after  the  first  upon  which  such  offence 
should  be  continued. 

And  whekeas  application  hath  been  made  to  the  Council,  by  of 

Eetail  Butcher,  for  a  Licence  for  the  killing  and  dressing  of  Cattle,  in 
situate  at  within  the  Parish  of  Liverpool. 

Now,  the  Council  of  the  said  City  of  Liverpool  do,  by  these  presents,  grant  a  Licence 
to  the  said  for  the  killing  of  Cattle,  within  the  Parish  of  Liverpool,  that 

is  to  say,  within  such  part  of  the  City  of  Liverpool  as  is  comprised  within  the  City,  as  the 
same  was  limited  prior  to  the  passing  of  an  Act  passed  in  the  Session  of  Parliament  held 
in  the  fifth  and  sixth  years  of  the  reign  of  his  late  Majesty  King  William  the  Fourth,  and 
intituled  'An  Act  to  provide  for  the  Eegulation  of  Municipal  Corporations  in  England  and 
Wales,'  under  the  conditions,  restrictions,  and  regulations  following,  that  is  to  say, 

1st.  The  said  shall  not  kill  or  dress,  or  permit  or  suffer  to  be 

killed  or  dressed,  any  Cattle  elsewhere,  within  the  said  Parish  of  Liverpool,  than  in  the 
said 

2nd.  The  said  shall  not  kill  or  dress,  or  permit  or  suffer  to  be  killed 

or  dressed  at,  or  in  the  said  Slaughter-house,  any  Cattle,  except  for  sale  in  his  shop  to  his 
ordinary  customers,  or  to  shipping,  or  for  some  other  similar  retail  Butcher,  who  shall  be 
Licensed  by  or  under  the  direction  of  the  Council. 

3rd.  If  the  said  shall  commit  any  breach  of  the  said  two  herein- 

before mentioned  conditions,  or  of  either  of  them,  this  Licence  shall  thereupon  forthwith 
become  and  be  void,  and  of  no  effect. 

4th.  If  the  said  shall  be  convicted  of  any  offence  within  the  City  of 

Liverpool,  against  any  of  the  provisions  of  any  Act  of  Parliament,  or  of  any  Bye-law  in 
relation  to  Slaughter-houses,  or  to  the  killing  or  dressing  of  Cattle  within  the  said  City, 
then,  and  in  such  case,  this  Licence  shall,  by  any  resolution  of  the  Council  to  determine 
and  make  void  the  same,  be  and  become  void,  on  the  expiration  of  one  calendar  month 
after  service  on  the  said  of  a  notice  in  wi'iting,  of  such  resolution. 

5th.  This  Licence  shall,  by  any  resolution  of  the  Council  to  determine  and  make  void 
the  same,  be  and  become  determined  and  absolutely  void,  on  the  expiration  of  three 


986  HYGIENE 

calenilar  months  after  service  on  the  said  of  a  notice,  in  >vriting,  or  of 

such  resolution,  as  last  aforesaid. 

6th.  The  service  of  such  notice,  as  is  mentioned  in  the  said  4th  and  oth  conditions 
respectively,  shall  be,  either  by  the  delivery  of  a  Copy  thereof  to  the  said 
personally,  or  by  leaving  a  Copy  thei'eof  at  his  Dwelling-house,  or  last  known  place  of 
abode,  within  the  City,  or  by  affixing  the  same  on  the  outside  of  the  said 

7th.  This  Licence  shall  not  be  of  any  effect  until  the  Certificate  at  the  foot  thereof 
shall  have  been  signed  by  the  Medical  Officer  of  Health  of  the  said  City  for  the  time 
being.  ,  Town  Clekk. 

I  licrchy  Certify  tlmt  the  in  tJiis  Licence  meiitioned 

is  in  a  fit  and  proper  state  aiul  condition  for  the  killing  and  dressing  of  Cattle  tlierein. 

Liverpool,  the  day  of  18     . 

Eegistered  No.       .  ,  Medical  Officer  of  Health. 

In  London  at  the  present  time  the  requirements  for  private  slaughter- 
houses are  much  greater  under  the  London  County  Council  than  formerly. 
Overcrowding  is  prevented  by  insisting  on  2-i  square  feet  of  floor  space 
in  every  pound  for  cattle,  8  square  feet  for  calves,  and  G  square  feet  for 
sheep,  lambs,  and  pigs ;  and  every  animal  must  be  '  provided  with  a  suf- 
ficient quantity  of  wholesome  water  and  food.'  The  bye-laws  of  the 
Council  also  contain  provisions  prohibiting  the  slaughtering  of  cattle  in  the 
public  view,  or  in  view  of  any  other  animal,  and  requiring  the  taking  of 
precautions  to  prevent  unnecessary  suffering  to  the  animal  slaughtered.  The 
usual  pro^dsions  relating  to  the  use  of  receptacles  for  the  refuse  products,  the 
removal  from  the  premises  of  these  products,  of  the  hides,  tripes,  and  offal, 
and  the  cleansing  of  the  premises  and  receptacles,  are  embodied  in  the  bye- 
laws.  Some  of  the  more  important  requirements  relate  to  the  structure  of 
the  premises.  The  entrance  or  approach  to  every  slaughter-house  must 
be  not  less  than  3  feet  6  inches  wide,  and  the  approach  must  not  be  up  or 
down  steps,  nor  over  a  steeper  gradient  than  one  in  four.  The  entrance  or 
approach  to  slaughter-houses  for  sheep,  lambs,  and  pigs  only,  need  not  have 
a  greater  width  than  2  feet  9  inches.  The  bye-laws  also  require  the  proper 
lighting,  ventilation,  paving,  and  drainage  of  every  slaughter-house,  pound, 
pen,  and  lair,  and  the  provision  of  water  supply,  water  fittings,  and  wall 
coverings  ;  no  room  over  a  slaughter-house  may  be  used  for  human  habitation, 
nor  may  any  water-closet,  pri\7,  urinal,  or  stable  be  in  direct  communica- 
tion with,  or  ventilate  into,  a  slaughter-house.  The  requirements  for  new 
slaughter-houses  are  still  greater.  The  slaughter-house  and  its  poundage 
must  be  at  least  20  feet  from  any  inhabited  building,  and  must  not  have  any 
entrance  opening  directly  on  a  public  highway.  Every  slaughter-house  must 
have  an  adequate  place  for  the  accommodation  or  poundage  of  the  cattle 
about  to  be  slaughtered,  with  an  entrance  way  for  the  cattle  otherwise  than 
through  the  slaughter-house  ;  and  the  slaughter-house  and  its  poundage  must 
have  an  entrance  apart  from,  and  independent  of,  any  shop  and  dwelling- 
house,  and  be  properly  lighted  by  lantern,  sky,  or  side  lights.  The  floor 
of  the  premises  must  not  be  below  the  level  of  the  outside  road  or  footway. 

However  excellent  the  construction  of  bye-laws  may  be,  no  profound  ex- 
perience or  knowledge  of  the  world  is  needed  to  show  that  the  amount  of 
attention  paid  to  their  requirements,  and  consequently  the  amount  of  good 
they  are,  will  depend  upon  the  stringency  with  which  their  provisions  are  en- 
forced. Without  active  supervision,  the  slaughtering  places  of  a  town  possessed 
of  unimpeachable  bye-laws  will  become  centres  of  offence  and  a  menace  to 
the  health  of  the  locality  ;  not  only  so,  but  they  may  furnish  a  ready  means 
for  the  disposal  of  meat  which  is  unfit  for  human  food  ;  but  before  referring 
to  the  question  of  inspection,  the  important  subject  of  pubhc  abattoirs  may- 
be considered. 


V 

a, 
o 
X 


30NV81N3 


—I 


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1-- 


SLAUGHTER-HOUSES  AND   THEIR  ADMINISTRATION    987 

Many  towns,  such,  for  example,  as  Huddersfiold,  Edinburgh,  Manchester, 
Liverpool,  Swansea,  and  other  places,  are  possessed  of  public  abattoirs,  some 
of  them  being  of  recent  construction,  and  others  erected  some  twenty  or 
thirty  years  back.  Generally  speaking,  these  places  have  been  estabhshed 
in  order  to  remove  the  evil  which  resulted  from  the  number,  and  the  then 
condition,  of  the  private  slaughter-houses  in  those  towns.  It  was  no  doubt 
fully  recognised  that  whatever  steps  may  be  taken  to  improve  the  health  of  a 
town  by  cleansing,  scavenging,  sewering  and  the  like,  they  will  be  rendered 
ineffectual  if  slaughter-houses  and  the  attendant  and  collateral  trades  are 
allowed  to  continue  in  densely  populated  quarters,  and,  as  is  commonly 
the  case,  in  the  narrowest  and  most  ill- ventilated  streets  of  those  quarters. 
Consequently  the  aim  appears  to  have  been  to  limit  the  number  of  these 
places  to  the  actual  requirements  of  the  people,  and,  as  circumstances 
permitted,  to  effect  their  removal,  and  the  transference  of  the  business  to 
more  suitable  surroundings. 

The  importance  of  an  open  site,  where  the  various  offensive  emanations 
may  be  freely  diluted  with  abundance  of  fresh  air,  cannot  be  too  strongly 
insisted  upon  ;  and,  when  such  a  site  is  available,  care  must  be  taken  to 
prevent,  or  at  least  control,  the  erection  of  dwellings  adjacent  to  the  slaughter- 
ing places ;  for  we  find  that  the  abattoirs  of  several  towns,  those  more  es- 
pecially which  were  established  some  twenty  or  thirty  years  ago,  have  been 
surrounded  by  dwellings,  which  in  course  of  years  have  encroached  upon 
what  were  originally  open  sites.  As  a  consequence  of  this,  the  removal  of 
public  abattoirs  sometimes  becomes  a  matter  for  serious  consideration,  and, 
needless  to  say,  it  is  a  question  less  easy  of  solution  than  is  the  dealing  with 
the  smaller  interests  of  a  private  slaughter-house.  It  may  be  remarked  that 
the  argument  has  been  put  forward  against  the  removal  of  these  places, 
that  the  transfer  of  carcases  to  any  considerable  distance,  e.g.  by  rail,  has  a 
prejudicial  effect  upon  the  meat ;  but  this  is  incorrect :  indeed,  the  condition 
in  which  meat  arrives  from  the  United  States  or  distant  colonies,  after 
thousands  of  miles  of  travel,  provided  due  care  is  taken  in  packing  and 
unpacking,  sufficiently  disposes  of  the  objection. 

The  selection  of  a  site  would  be  further  influenced  by  the  facilities  afforded 
for  bringing  cattle  to  it,  and  again  by  the  means  available  for  the  removal  and 
distribution  of  the  meat.  Consideration  would  also  be  given  to  the  conveniences 
for  dealing  with  hides,  blood,  intestines,  and  the  like,  and  for  such  treatment 
of  these  and  other  products  as  it  may  be  desirable  to  adopt. 

The  site  to  be  preferred,  then,  would  be  one  sufficiently  removed  fi-om  dwel- 
lings to  ensure  that  all  offensive  vapours,  whether  from  the  animals  themselves^ 
or  from  blood,  garbage,  or  the  decompositions  of  washings  and  the  like,  should 
have  abundance  of  fresh  air  for  their  dilution  ;  it  should  include  a  sufficient 
number  of  acres,  not  only  to  meet  present  requirements,  but  to  admit  of  ex- 
tension of  the  premises  as  the  population  of  the  district  increases  and  the 
trade  expands  ;  it  should  be  ready  of  access,  and,  if  the  meat  is  intended  for 
consumption  in  distant  parts  of  the  country,  within  easy  reach  of  a  railway. 

The  general  plan  of  the  arrangement  of  the  various  components  of  the 
business  is  simple.  (See  diagram,  Plate  VIII.)  The  cattle  market,  including 
lairages  and  pens  for  cattle,  sheep,  and  pigs,  would  occupy  about  one-half  the 
area ;  the  remaining  half  will  be  occupied  by  the  abattoirs  proper,  comprising 
slaughter-houses,  parallel  to  and  in  the  rear  of  which  will  be  lairages  which 
are  duly  separated  therefrom,  while  in  front  of  the  slaughtermg-places,  and 
separated  from  them  by  a  roadway  some  12  feet  wide,  will  be  the  meat  market. 
The  meat  market  may  be  connected  with  the  slaughtering-booths  by  overhead 
meat-beams,  the  object  of  the  roadway  being  to  facilitate  the  removal  of  blood 


088  HYGIENE 

and  other  materials,  the  meat  itself  heing  most  conveniently  removed  from 
the  opposite  side  of  the  meat  market.  This  sketch  is  of  course  liable  to  many 
modifications.  At  Swansea,  the  abattoirs  (see  Plate  IX.)  are  of  stone  with  local 
*  polled  stone  '  facing,  lined  intenially  with  white  glazed  bricks  to  a  height  of 
G  feet ;  above  this  the  rubble-faced  wall  is  white-limed.  The  floors  of  the 
killing  houses  and  cooling  rooms  are  of  Wilkinson's  patent  granite  concrete ; 
but  this  being  found  to  be  sUppery,'  in  a  recent  addition  ordinary  flags  have 
been  used  with  satisfactory  results.  The  floors  of  the  lairs  are  of  blue  stable 
bricks  (Doulton's).  Provision  for  artificial  lighting  is  made  by  gas  brackets, 
so  placed  as  not  to  interfere  with  the  hoisting  and  hanging  machinery. 

The  site  is  bounded  on  three  sides  by  streets  about  80  yards  wide,  with  no 
houses  or  buildings  on  the  sides  of  the  streets  next  the  slaughter-houses. 
The  lairs  are  only  separated  from  the  killing-houses  by  a  passage  6  feet  wide, 
this  arrangement  being  made  with  a  view  to  get  the  animals  easily  from  the 
lairs  to  the  slaughter-houses.  The  cooling  rooms  are  to  a  certain  extent  used 
as  a  dead-meat  market,  the  carcases  being  here  sold  wholesale  and  then  con- 
veyed to  the  retail  market  about  half  a  mile  away. 

The  cattle-market  adjoins  the  slaughter-house  buildings,  and  contains 
lairs  for  beasts  and  sheep,  and  also  pig  pens,  all  covered  and  protected  from 
the  weather  ;  there  being  no  open  pens  in  the  market. 

At  Huddersfield  there  is  a  similar  proximity  of  the  abattoir  to  the  cattle 
market.  Both  are  well  situated  in  an  open  locality  removed  from  dwellings. 
The  premises  are  enclosed  and  are  provided  with  an  attractive  approach.  As 
in  the  preceding  case,  the  lairages  are  appropriately  separated  from  the 
slaughtering-place,  the  animals  being  driven  in  as  required  ;  the  slaughtering- 
places  are  merely  recessed  off  from  the  meat  market.  The  floor  is  of  concrete  ; 
the  walls  have  white  glazed  bricks  to  a  height  of  8  or  9  feet,  and  there  is  a 
good  north  top  light.  The  piggery,  which  is  separate,  is  of  similar  construc- 
tion, and  is  provided  with  steaming  apparatus. 

The  total  area  covered  by  the  slaughter-houses,  yards,  &c.,  is  7,198  square 
yards,  of  which  1,598  square  yards  are  available  for  future  extension.  The 
cattle  market  covers  an  area  of  1  acre  1  rood  12  perches  ;  the  animals 
passmg  through  it  last  year  were  8,438  beasts,  2,263  pigs.  At  the  slaughter- 
houses during  the  same  period,  the  number  of  animals  killed  was  5,255 
beasts,  2,524  calves,  13,000  sheep,  5,985  pigs. 

The  planning,  structure,  and  administration  of  these  premises  are  all 
good. 

At  Liverpool,  although  the  management  is  good,  the  structure  of  the 
older  parts  of  the  abattoirs  is  defective,  and  the  site,  though  excellent  for  a 
meat  market,  is  not  all  that  could  be  desired  for  an  abattoir.  The  regulations 
of  the  Liverpool  Abattoir  Company  are  as  follows  : — 

1.  That  the  Lairs  of  the  Abattoir  Company  are  only  intended  for  the  acconmiodation 
of  animals  brought  on  to  the  Company's  premises  for  the  purpose  of  being  slaughtered 
there  ;  therefore,  and  for  the  purpose  of  preventing  the  spread  of  Cattle  Disease,  and  the 
Abattoir  being  closed  by  orders  of  the  Privy  Council  or  otherwise,  which  would  cause  great 
loss  and  inconvenience  to  the  Company  and  persons  using  the  Abattoir,  no  Ox,  Cow,  Bull, 
Calf,  Pig,  Sheep,  Lamb,  or  Goat,  brought  on  to  the  Company's  premises,  shall  be  removed 
therefrom  until  after  it  is  slaughtered. 

2.  That  for  the  more  conveniently  carrying  on  the  business  of  the  Company,  the 
Directors  reserve  power  of  appointing  from  time  to  time  the  most  convenient  hours  for  re- 
ceiving animals,  slaughtering,  selling  dead  meat,  and  doing  any  other  act,  matter,  or  thing, 

3.  That  during  the  time  from  7  o'clock  to  10  o'clock  in  the  mornings  of  Tuesdays, 
Wednesdays,  and  Thursdays,  and  during  the  time  from  4  o'clock  to  6  o'clock  in  the  after- 

'  Generally  speaking,  slipperiness  can  be  overcome  by  a  judicious  sprinkling  with  saw- 
dust. 


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SLAUGIITEB-HOUSES  AND   THEIR  ADMINISTBATION    OSO 

noons  of  Mondays,  Wednesdays,  and  Thursdays,  no  Cattle,  Calves,  or  Sheep  shall  be 
brought  on  to  the  Company's  premises  except  by  either  of  the  entrances  Nos.  15,  in  Trow- 
bridge Street,  16,  in  Copperas  Hill,  19,  20,  &  22,  in  St.  Andrew  Street,  or  into  the  Chapel 
and  the  Piggery ;  and  no  cattle  shall  during  the  same  times  be  taken  out  of  either  of  the 
North-end  Lairs  in  Trowbridge  Street  or  St.  Andrew  Street. 

4.  That  the  number  of  animals  which  may  be  brought  into  the  Lairs,  and  from  the 
Lairs  or  the  Street  or  otherwise,  into  the  slauglitcring-place  at  one  time  by  any  owner, 
shall  be  regulated  from  time  to  time  by  the  Directors  or  their  Servant  or  Servants,  in  such 
manner  as  they  may  deem  proper,  for  preventing  overcrowding  or  inconvenience  in  the 
slaughtering-place. 

5.  That,  except  during  such  times  as,  in  consequence  of  any  Regulation  or  Order  in 
relation  to  the  prevention  of  Cattle  Disease,  the  Directors  shall  otherwise  direct,  no  animal 
shall  be  allowed  to  remain  on  the  Company's  premises  unslaughtered  for  more  than  forty- 
eight  hours. 

6.  If  any  animal  is  left  on  the  Company's  premises  for  more  than  forty-eight  hours, 
excejDt  when  the  Directors  shall  otherwise  direct  as  above-mentioned,  and  then  for  more 
than  the  time  directed,  without  being  slaughtered,  the  Directors  or  their  servant  or  servants 
may  cause  such  animal  to  be  slaughtered,  and  charge  the  owner,  or  person  who  brought 
or  caused  to  be  brought  such  animal  on  to  the  Company's  premises,  with  all  costs,  charges, 
and  expenses  incurred,  in  addition  to  any  tolls  or  other  charges  ;  and  may  sell  all  or  any 
part  of  the  carcass,  hide,  skin,  fat,  offal,  or  other  part  of  such  animal,  and,  out  of  the 
moneys  received  therefor,  retain  and  reimburse  themselves  the  costs,  charges,  and  ex- 
penses of  carrying  the  powers  and  provisions  hereof  into  effect,  and  all  tolls,  charges,  and 
payments  owing  or  payable  to  the  Company  by  the  owner  of  such  animal,  or  the  person 
or  persons  who  brought  or  caused  to  be  brought  such  animal  on  to  the  Company's  premises 
or  any  other  person  in  respect  of  such  animal. 

7.  That  all  Cattle  brought  on  to  the  Company's  premises  shall  be  tied  up,  and  all 
animals  shall  be  placed  in  such  Lairs,  and  the  slaughtering  shall  take  place,  and  all 
carcasses  and  dead  meat  shall  be  hung,  and  all  other  parts  of  the  animals  shall  be  deposited, 
where  and  as  the  Directors  or  their  servant  or  servants  shall  from  time  to  time  direct,  as 
most  conducive  to  the  carrying  on  of  the  business  of  the  Company  and  the  convenience 
of  the  persons  resorting  to  their  premises. 

8.  That  what  are  known  as  smothered  animals  shall  (if  fit  for  human  food)  be  dressed 
as  soon  as  possible  after  arriving  at  the  Company's  premises  ;  and  the  several  Bye-Laws, 
Eules,  and  Eegulations  shall  (as  far  as  applicable)  be  applied  to  such  animals  and  their 
products,  as  if  they  had  been  slaughtered  on  the  Company's  premises. 

9.  Complaints  have  been  made  to  the  Directors  of  Cattle  and  other  animals  being 
kept  on  their  premises  an  unreasonable  time,  without  food  and  water ;  therefore, 
no  animal  shall  be  kept  on  their  premises  more  than  twenty-four  hours  without  being 
fed  and  watered. 

10.  There  shall  be  paid  to  the  Company,  in  respect  of  animals  slaughtered  on  the 
Company's  premises,  the  following  tolls  or  payments,  viz. : — 

for  each  Ox,  Cow,  or  Bull Is.  6^. 

for  each  Sheep,  Lamb,  or  Goat l\d. 

and  for  each  Calf  or  Pig Qd. 

and  there  shall  be  paid  to  the  Company,  in  respect  of  every  carcass  brought  on  to  the 
Company's  premises  but  not  slaughtered  thereon,  the  following  tolls  or  payments,  viz. : — 

of  an  Ox,  Cow,  or  Bull Is.  &d. 

of  a  Sheep,  Lamb,  or  Goat l^d. 

of  a  Calf  or  Pig Qd. 

and  for  all  dead  meat  in  pieces  less  than  a  carcass,  such  sum  as  the  Directors  or  their 
servants  shall  decide  is  a  fair  and  just  payment,  in  proportion  to  what  is  payable  in 
respect  of  a  carcass. 

11.  There  shall  be  paid  to  the  Company,  in  such  cases  as  the  Directors  or  their 
servants  shall  think  fit  to  enforce  the  same,  in  respect  of 

each  Ox,  Cow,  or  Bull 3d. 

each  20  Sheep,  Lambs,  or  Goats Is. 

and  a  proportionate  amount  for  any  smaller  number  ; 

each  Calf 3d. 

and  each  Pig l\d. 


990  HYGIENE 

for  every  twentj'-four  hours,  or  less  time  than  twenty-four  hours,  beyond  the  first  forty- 
eight  hours,  during  which  such  animal  shall  remain  on  the  Company's  premises  un- 
slaughtered. 

12.  That  if  any  animal  shall  be  sold  while  alive  and  on  the  Company's  premises,  there 
shall  be  paid  to  the  Company,  in  addition  to  all  other  tolls,  rates,  and  charges,  the  sum 

of 

for  each  head  of  Cattle <>"• 

for  each  20  Sheep,  Lambs,  or  Goats   .         .         .         .Is. 

and  a  proportionate  amount  for  any  smaller  quantity ; 

for  each  Calf 3d. 

for  each  Tig la^- 

so  sold. 

13.  Every  person  who  shall  slaughter,  or  cause  to  be  slaughtered,  any  animal  in  or 
upon  the  premises  of  the  Company,  shall  carefully  collect  or  cause  to  be  collected  the 
blood  flowing  therefrom,  in  the  utensil  provided  for  that  purpose  by  the  Directors. 

14.  That  every  person  so  slaughtering,  or  causing  to  be  slaughtered,  as  aforesaid, 
shall  deposit  and  leave  in  such  place  or  places  on  the  premises  as  the  Directors  or  their 
servant  or  servants  shall  from  time  to  time  direct,  the  Garbage,  Gall,  Blood,  Intestines, 
Manifolds,  Slinks,  Pig's  Hair,  Eops,  Sheep's  Bellies,  Bladders,  and  Manure  produced 
from  each  animal  slaughtered,  excepting  the  Blood  and  Eops  of  Pigs. 

15.  That  the  Blood,  Garbage,  and  other  matters  mentioned  in  the  14th  Bye-Law, 
Regulation,  or  Eule  shall  be  the  property  of  the  Company,  and  the  same  shall  absolutely 
pass  to  and  vest  in  the  Company. 

16.  All  former  Bye-Laws,  Eules  and  Eegulations,  made  and  issued  by  the  Directors 
are  withdrawn,  and  have  ceased  to  take  effect,  except  in  respect  to  any  act,  matters, 
rights,  duties,  and  liabilities  before  the  making  of  these  Bye-Laws,  Eules  and  Eegulations, 

17.  That  each  slaughterer  shall,  immediately  after  any  slaughtering  takes  place,  well 
and  effectually  sweep,  wash,  and  cleanse  the  place  used. 

18.  The  Company  will  not  be  liable  for  the  safe  custody  of  any  animal,  dead  meat,  or 
other  part  of  any  animal,  or  any  damage  or  injury  to  any  animal,  or  dead  meat,  or  other 
part  of  any  animal,  whilst  on  the  Company's  premises ;  and,  for  the  purpose  of  this  rule, 
the  respective  owners  of  animals,  and  dead  meat,  or  parts  of  any  animal,  shall  be  deemed 
and  considered  to  have  the  sole  custody,  care,  and  preservation  of  the  same. 

19.  Any  person  making  a  false  return  to  any  of  the  Company's  servants,  of  their 
weekly  or  other  slaughter,  will  not  be  allowed  to  slaughter  any  more  on  any  part  of  the 
Company's  premises,  or  to  bring  thereon  any  animal,  carcass,  or  part  of  any  animal. 

20.  That  the  Company  shall  have  a  general  lien  on  all  live  and  dead  animals,  dead 
meat  and  parts  of  animals,  for  all  moneys  owing  or  payable  to  the  Company  in  respect 
thereof  by  any  person  or  persons  whomsoever,  and  shall  be  entitled  to  enforce  such  lien  by 
seizure  and  sale,  without  any  further  authority. 

21.  AU  persons  while  upon  the  Company's  premises  shall  obey  the  orders  of  the 
Directors  and  their  servant  or  servants,  and  shall  behave  in  an  orderly  and  proper  manner, 
and  shall  attend  to  and  conduct  their  business  therein  in  such  a  way  as  not  to  cause 
annoyance  or  obstruction  to  any  other  person. 

22.  No  person  who  has  not  proper  and  sufficient  business  to  be  on — or  who  shall  not, 
on  request,  satisfy  the  Directors  or  their  servant  or  servants  that  he  has  proper  and 
sufficient  business  to  be  on— the  premises,  shall  be  or  remain  on  the  premises  of  the 
Company ;  and  the  Directors  or  their  servant  or  servants  shaU  be  at  liberty  to  forcibly 
eject  from  their  premises  all  persons  who  do  not,  on  request,  satisfy  them  that  they  have 
proper  and  sufficient  business  to  be  on  the  premises. 

23.  The  Directors,  their  servant  or  servants,  shall  be  at  liberty  to  forcibly  eject  from, 
and  prevent  from  again  coming  on  to  the  premises,  any  person  who  shall  not  observe, 
comply  with,  and  conform  to  these  Bye-Laws  and  Eules. 

24.  All  dogs  on  the  Company's  premises  during  the  time  from  7  o'clock  to  10  o'clock 
in  the  mornings  of  Tuesdays,  Wednesdays,  and  Thursdays,  and  during  the  time  from  4 
o'clock  to  6  o'clock  in  the  afternoons  of  Mondays,  Wednesdays,  and  Thursdays,  and  on 
Fridays,  from  7  a.m.  to  5  p.m.,  belonging  to  any  person  having  animals,  carcasses,  or  other 
dead  meat,  or  to  the  servants  of  such  persons,  shall  be  securely  chained,  tied  up,  or  other- 
^vlse  confined,  so  that  they  may  not  cause  annoyance  or  inconvenience  to  persons  having 
business  on  the  Company's  premises. 

Something  more  than  a  general  impression  with  regard  to  the  relative 
advantages  of  public  and  private  slaughter-houses  will  have  been  derived  from 


SLAUGHTEB-HOUSES  AND   TEE  IB  ADMINISTBATION    991 

the  foregoing  pages.  If  slaughtering  and  its  attendant  industries  are  offensive 
or  hable  to  become  so,  or  are  of  such  a  nature  as  to  require  jealous  watching 
and  careful  administration  to  prevent  them  becoming  injurious  to  health,  it 
is  clearly  desirable  to  minimise  the  numbers  of  such  establishments  to  the 
necessities  of  the  trade.  Furthermore,  practical  experience  confirms  the  view 
that  more  economy  and  greater  efficiency  are  found  by  centralising  the  trade 
in  one  well-conducted  establishment,  than  can  be  looked  for  when  every  butcher 
slaughters  in  his  own  more  or  less  ill-adapted  back  premises  at  irregular 
intervals  to  meet  the  requirements  of  a  small  retail  trade.  Again,  the  diffi- 
culties in  the  way  of  inspection,  and  the  prevention  of  the  sale  of  unsound 
meat,  are  greatly  increased  when  supervision  has  to  be  extended  to  a  multitude 
of  small  out-of-the  way  places,  numbering  as  they  do  in  one  important  town 
as  many  as  40,  in  another  as  many  as  GO,  and  in  a  third  upwards  of  200. 
Such  conditions  afford  facilities  for  the  disposal  of  unsound  meat  which  are 
practically  beyond  the  control  of  inspectors  ;  and  indeed  the  position  in  these 
cases  is  frequently  still  further  complicated  by  the  practice  of  licensing 
several  retail  butchers  to  kill  on  the  same  premises,  thus  putting  still  further 
obstacles  in  the  way  of  fixing  responsibility  and  preventing  improper  conduct. 
With  the  prompt  and  multiplied  means  of  transit  now  available,  there  no 
longer  exists  any  necessity  for  private  slaughter-houses  in  towns,  and  it  may 
be  hoped  that  the  establishment  in  their  place  of  public  abattoirs  upon 
salubrious  sites  is  merely  a  question  of  time. 

We  come  now  to  the  work  of  inspection,  the  objects  of  which  are  twofold, 
viz.  (1)  to  insure  that  meat  intended  for  the  food  of  man  shall  be  in  good  and 
wholesome  condition,  and  (2)  to  provide  for  the  observance  of  the  bye-laws 
and  the  proper  conduct  of  the  business.  The  powers  exercised  by  sanitary 
authorities  are  derived  from  several  sources — viz.  various  local  Acts,  and  bye- 
laws  based  upon  them  ;  the  Contagious  Diseases  (Animals)  Acts,  and  Orders 
of  Council  made  thereunder ;  and  the  Public  Health  Act. 

Public  abattoirs  will  require  the  presence  of  the  inspector,  at  least  several 
hours  a  day  if  an  extensive  business  is  carried  on.  Visits  should,  of  course, 
■also  be  paid  at  irregular  intervals.  All  private  slaughter-houses  should  be 
visited  at  least  once  a  day,  oftener  if  the  business  is  a  large  one.  The  twenty- 
eight  private  slaughter-houses  in  Liverpool  are  visited,  some  daily,  others  two 
or  three  times  a  day.  As  an  index  to  the  extent  of  business  needing  this 
supervision,  it  may  be  stated  that  the  number  of  animals  killed  in  these  private 
slaughter-houses  during  the  year  amounted  to  10,500  cattle,  45,000  sheep, 
3,000  calves,  and  48,000  pigs.  At  the  public  abattoirs  the  numbers  killed 
in  the  same  period  were,  29,841  cattle,  192,000  sheep,  17,096  calves,  and 
22,000  pigs  ;  large  quantities  of  imported  dead  meat  were  also  sold  at  these 
premises.  In  regard  to  the  method  of  meat  inspection  pursued  in  Liverpool, 
the  services  of  the  Medical  Officer  of  Health,  his  deputy,  and  the  veterinary 
superintendent  are  all  available  when  required,  and  in  addition  there  are  six 
meat  inspectors,  each  of  whom  has  a  separate  district  and  specific  duties 
allotted  to  him,  and  is  invested  with  authority,  in  conformity  with  the  require- 
ments of  the  several  Acts  already  referred  to.  These  inspectors  are  selected 
with  great  care  from  men  physically  fit,  of  unquestionable  character,  and  with 
practical  experience  as  butchers  acquired  in  the  public  abattoirs,  and  are 
required  to  give  proof  of  a  thorough  acquaintance  with  all  classes  of  meat 
before  undertaking  the  duties  of  inspector.  Their  salaries  range  from  120Z. 
to  225L  per  annum. 

The  officers  of  the  Corporation  exercise  no  control  over  meat  in  transit ; 
and  their  responsibihty  is  limited  to  animals  slaughtered,  or  meat  brought  for 
sale  within  the  city,  whether  intended  for  consumption  within  the  mimicipal 


992  HYGIENE 

boundary  or  not.  It  is  almost  unnecessary  to  remark  that  the  mere  presence 
of  diseased  meat  upon  licensed  premises  does  not  necessarily  constitute  a 
ground  for  prosecution  ;  for,  on  the  one  hand,  diseased  animals  are  not 
infrequently  sent  to  these  places  for  convenience  of  slaughter  and  removal 
of  the  hides,  &c.  ;  and  on  the  other  hand,  disease,  such  as  cysticcrcus,  which 
renders  an  animal  unfit  for  food,  may  be  incapable  of  detection  during  life, 
and  be  only  ascertainable  when  the  animal  undergoes  the  process  of  dressing. 
In  cases  such  as  these,  it  is  the  duty  of  the  person  who  is  in  possession  of  the 
carcase  to  remove  it  to  some  specified  part  of  his  premises,  away  from  the 
place  where  meat  is  usually  sold  or  deposited  for  the  purpose  of  sale  ;  the 
inspector  then  calls  a  jury  of  three  members  of  the  trade,  who,  with  the 
owner,  agreeing  as  to  the  condition  of  the  meat,  sign  a  certificate  to  that 
effect,  and  the  meat  is  destroyed  ;  no  magistrate's  order  being  necessary  in 
these  cases.     A  small  fee  is  paid  to  the  jurors  who  view  the  meat. 

For  reasons  which  are  sufficiently  obvious,  it  is  preferable  that  suspected 
animals  should  be  sent  to  the  public  abattoirs  rather  than  to  private  slaughter- 
houses ;  disease  existing  in  animals  killed  at  the  former  place  probably  never 
escapes  detection,  and  the  chances  of  unwholesome  meat  being  removed 
therefrom  for  consumption  are  practically  nil. 

With  regard  to  the  very  different  class  of  cases  in  which  attempts  are 
knowingly  and  intentionally  made  to  dispose  of  unsound  meat  for  human 
food,  it  is  well  to  emphasise  the  provisions  of  sections  IIG,  117,  118,  119  of 
the  Public  Health  Act,  which  enable  the  Medical  Officer  of  Health  or  Inspec- 
tor to  examine  any  meat  exposed  for  sale  and  intended  for  the  food  of  man, 
the  onus  of  proof  that  it  loas  not  so  intended  lying  tvith  the  party  charged  ; 
and  the  Act  provides  that,  if  such  meat  appear  unfit  for  the  food  of  man,  the 
officer  may  seize  the  same  in  order  to  have  it  dealt  with  by  a  justice.  It  will 
be  noted  that  the  Act  does  not  convert  the  Medical  Officer  or  Inspector  into 
an  arbitrator  whose  function  it  shall  be  to  advise  dealers  in  meat  what  is 
sound  and  what  is  unsound,  what  may  be  exposed  for  sale  and  what  may 
not,  but  it  assumes  that  the  dealer  has  a  competent  knowledge  of  his  trade 
and  merely  directs  the  officer  to  seize  what  in  his  opinion  is  unsound,  and 
have  the  matter  decided  by  the  magistrate. 


INDEX 


ABA 

Abattoibs,  public,  arrangements  for,  987 

inspection  of,  991 

ABC  process  for  precipitation  of  sewage, 

866 
Acids,  vegetable,  as  foods,  396 
Acre,  density  of  population  to,  as  affecting 

health,  656 
Acts,   dealing    with    housing    of    working 

classes,  674 
Adults,  relative  heights  of,  under  varying 

conditions,  546 

—  selection  of  exercises  for,  613 
Affusion,  cold,  as  an  antipyretic,  632 
Age  as  influencing  choice  of  diet,  407 
Agricultural  labourers,  dwellings  for,  676 
Air,  amount  of  carbon  dioxide  in,  3,  9,  23, 

44 

— oxygen  in,  3 

required   for   ventilation,   13,   18, 

116 

in  hospitals,  20 

schools,  21 

—  bacteria  in,  5,  28 

—  carbon  dioxide  as  a  standard  of  impurity 
of,  17 

estimation  of,  in,  23 

—  chemical  analysis  of,  23 

—  composition  of,  3 

—  condition  of,  as  influencing  evaporation, 
47 

—  diseases  associated  with  impurities  in,  9 
produced  by  impurities  in,  6 

—  distribution  of  heat  by,  131 

—  dust  and  smoke  in,  48 

in,  essential  to  formation  of  fogs,  47 

—  dynamical  cooling  of,  42 

—  effect  of  current  of,  in  producing  evapo- 
ration, 47 

—  estimation  of  free  and  albuminoid  am- 
monia in,  27 

hygrometric  condition  of,  28 

■ —  oxidisable  substances  in,  26 

—  examination  of,  22 
micro-organisms  in,  28 

—  excessive  humidity  of,  in  factories,  10 

—  filtration  of ,  51 

—  flow  of,  through  room  with  open  fire,  98 

—  gaseous  matters  in,  9 

—  hydrogen  sulphide  in,  10 

—  impurities  in,  4,  13,  49 

derived  from  walls  and  floors,  16 

—  detection  of,  16 

VOL.   I. 


ALC 

Air,  impurity  of,  in  connection  with  plague 
and  pestilence,  651 

—  law  of  continuity  of  flow  of,  53 

—  local  circulation  of,  85 

—  metallic  dust  and  fumes  in,  as  causes  of 
disease,  7 

—  motion  of,  through  tubes  and  apertures, 
52,55 

—  of  brickfields,  12 
graveyards,  12 

—  —  marshes,  13 

sewers,  composition  of,  840 

—  organic  effluvia  in,  10 
suspended  matters  in,  5 

—  organised  bodies  in,  8 

—  ozone  in,  4 

—  physical  properties  of,  41 

—  purity  of,  a  condition  of  healthfulness 
of  dwellings,  651 

—  quality  of,  for  efficient  respiration,  117 

—  respired,  aqueous  vapour  in,  14 

carbon  dioxide  in,  14 

organic  matter  in,  15 

—  saturation  of,  by  moisture,  45 

—  space,  cubic  measurement  of,  21 

—  suspended  matters  in,  4,  6,  44 

—  vitiated  by  combustion,  15 

exhalations  from  the  sick,  11 

gas  combustion,  11 

heating  apparatus,  118 

perspiration,  15 

respiration,  10,  13 

sewage  emanations,  11 

—  watery  vapour  in,  4,  44 

—  weight  of  cubic  foot  of,  41 

Airy,    Dr.,    on    circumstances    favouring 

prevalence  of  diphtheria,  337 
AiTEEN,  Mr.,  on  dust  and  smoke  in  air,  47 

effect  of  electricity  on  dusty  air,  51 

Albuminoid  ammonia  in  water,  286 
Albuminoids  as  food,  398 

—  change  of,  in  body,  396 
Albuminuria  as  a  result  of  sudden  change 

of  climate,  220 
Albumoses  as  food,  394 
Alcohol,    action    of,    on    central    nervous 

system,  485 

digestive  system,  477,  484 

heart,  484 

temperature,  484 

—  dietetic  use  of,  487 

—  physiological  action  of,  483 

3  s 


994 


HYGIENE 


ALC 

Alcohol,  symptoms  and  changes  produced 

by  excess  of,  485 
Alcoholic  beverages,  480 

classification  and  composition  of,  481 

physiological  action  of,  486 

—  preparations,  poisonous  action  of  various 
kinds  of,  486 

Algeria  and  Morocco,  climates  of,  212 
Alkaloids,  beverages  containing,  488 
Alum,  use  of,  to  adulterate  bread,  464 

precipitate  sewage,  858 

Amines,  process  for  dealing  with  sewage, 

868 
Ammoniacal  vapours  in  air,  10 
Amputations,  statistics  of,  before  and  after 

Listerism,  798 
Analyses  of  water,  standard  solutions  for, 

295 
Anemometers,  forms  of,  175 

—  use  of,  in  testing  ventilation,  104 
Aneurysm,  exercise  as  a  factor  in  produc- 
ing, 569 

Animals,  nuisances  connected  with  slaugh- 
tering, 899 

—  rules  for  conveyance  of,  by  water,  978 
Anstey,   Dr.,   on    innocuous    amounts    of 

alcohol,  484 
Anthrax,  bacillus  of,  376 

—  meat  of  animals   suffering   from,  447, 
502 

• —  methods  of  propagation  of,  930 

—  relation  of,  to  soil,  375 
Anti-scorbutics,  474 

Anti-septicism,  results  of,  in  lying-in  hos- 
pitals, 800 

—  use  of,  in   General   Lying-in  Hospital, 
803 

Antwerp,  plan  of  Civil  Hospital  at,  737 
Apparatus,  combinations  of,   for  warming 
and  ventilating,  141 

—  gymnastic,  599 

Aquatic   animals,   purification   of   streams 

by,  265 
Areas,  insanitary,  growth  of,  in  towns,  653 
Arro\^TOot,  starch  grains  of,  452 
Arsenic  in  wall  papers,  mischief  caused  by, 

8 

—  nuisance  and  danger  connected  with  use 
of,  in  industries,  952 

—  precautions  to  be  observed  by  workers 
in,  953 

Artesian  wells,  water  from,  240 

Artificial  lighting,  effects  of,  on  ventilation, 

114 
Artisans,  dwellings  for,  677 
Ash  closets,  816 
Asthma,  treatment  of,  by  compressed  air, 

644 
Asylums  for  the  insane,  754 
Atmospheric  burners,   for    use   in   stoves, 

129 

—  pressure,  measurement  of,  151 
Attendants,  hospital,  dresses  of,  783 
Automatic  siphon   flush  tank   for   subsoil 

irrigation,  888 

Bacillus  anthracis,  376,  931 

—  tuberculosis,  360 

Bacon,  nuisances  connected  with  curing  of, 
934 


BAT 

Bacteria  in  air,  5 

—  influence  of,  on  soil,  313 

—  recognition  of,  in  water,  296 
Ballahd,  Dr.,  on  causation  of  annual  mor- 
tality from  diarrhoea,  657 

—  -   on  connection  between  temperature 
and  diarrhcea,  303 

fatal  results  from  animal  food, 

505 

micro-organisms  in  diarrhoea,  366 

typhoid    from    contamination   of 

milk,  334 
Baltimore  Hospital,  ventilation  of,  762 
Bar,  horizontal,  use  of,  in  gj-mnastics,  602 
Baraques  in  German  hospitals,  732 
Bar-bells,  use  of,  in  gjTunastics,  601 
Barley  as  a  food,  464 

Baenham's  cowl  and  Boyle's  ventilator,  77 
Barometers,  aneroid,  155 

—  daily  range  of,  158 

—  Fortin's  and  Kew  patterns  of,  152 
: —  measurements  of  heights  by,  156 

—  positions  for,  153 

—  reading  of,  154 

—  recording,  156 

■ —  reduction  of,  to  sea-level,  157 

—  transport  of,  153 

—  various  kinds  of,  152 

Barometric  pressure  as  influencing  climate, 
192 

ventilation,  73 

effects  of  diminished,  193 

—  increased,  194 

Barracks,  English,  in  last  century,  697 

—  modern  arrangements  of,  698 

—  old  French  plans  of,  696 

—  plan  of  rooms  in,  699 

Barky,  Dr.,  on  flow  required  for  self-purifi- 
cation of  water,  266 
Bars,  parallel,  use  of,  in  gymnastics,  601 
Basement  buildings,  dangers  to  health  in, 

331 
Basins  for  w.cs.,  forms  of,  664 
Bassano  on  telluric  origin  of  tetanus,  373 
Bastille,  description  of  the  (1774),  G92 
Batem.^',   Mr.,   on   rainfall    available    for 

water  supply,  232 
Bath  and  bathroom,  construction  of,  645 
Baths,  absorption  of  substances  dissolved 
in,  628 

—  and  closets,  amounts  of  water  required 
for,  244 

—  bibliography  of,  647 

—  brine,  643 

—  cold,  620 

—  —  anti-pyi'etic  uses  of,  631 

efl'ects  of,  in  fever,  620 

on  body,  621 

—  respiration  and  circulation, 

622 

cutaneous  sensibility,  623 

tissue- waste  increased  by,  621 

used  locally,  624 

—  —  uses  of,  630 

—  electric,  645 

—  electrical  operations  of,  629 

—  for   school  children,  arrangements   for, 
711 

—  forms  of,  618 

—  history  of,  617 


i 


INDEX 


995 


BAT 

Baths,  hot  vapour,  or  Russian,  640  \ 
effects  and  uses  of,  641 

—  indifferent,  619  ; 
uses  of,  630 

—  local  hot-air,  640 

—  materials  for  construction  of,  646 

—  moor,  peat,  mud,  and  slime,  643 

—  mustard,  643 

— ■  of  compressed  air,  643 

— diseases  treated  by,  644 

—  outlet  pipes  for,  647 

—  physiological  action  of,  according  to 
constituents,  627 

according  to  temperature,  619 

—  pine  leaf,  643 

—  Russian  (see  Baths,  hot  vapour),  640 

—  sand,  643 

—  sea,  636 

—  Turkish,  contra-indications  for,  640 

—  —  description  of,  637 
effects  of,  638 

form  of,  for  home  use,  640 

uses  of,  639 

—  uses  of,  according  to  constituents,  636 
temperature,  630 

—  various  forms  of  artificial,  642 

—  warm,  effects  of,  625 
local,  627 

—  —  uses  of,  634 

Beans  and  peas,  digestibility  of,  470 

starch-grains  of,  452 

Beakd  and  Rockwell  on  electric  baths,  645 

Beaumont  on  digestibility  of  articles  in 
stomach,  419 

Becheb,  Dr.,  on  increase  of  bodily  tempera- 
ture with  that  of  air,  189 

Bedding,  hospital,  cleaning  of,  782 

Beef,  sound,  characteristics  of,  496 

Beef-tea,  449 

Beer,  action  of,  486 

—  composition  of,  481 

—  effect  of,  on  digestion,  478 
Beggiatoa  alba  (sewage  fungus),  growth  of, 

884 
Bennett,   Mr.,   on   causation   of    varicose 

veins,  570 
Berlier  system  of  sewage,  850 
Berlin,  Moabit  Hospital,  plan  of,  739 
Beverages  containing  alcohol,  480 

alkaloids,  488 

Bichromate  of  potassium,  poisoning  by,  953 

Bicycles,  forms  of,  586 

Biefel  and  Poleck,  analysis  of  coal-gas,  949 

Biscuits,  composition  of,  460 

Blackimn's  air-propeller,  80 

Blandfoed,  Mr.,  on  land  and  sea  breezes, 

198 
Blood,  preparation  of,  for  Turkey  red,  906 

—  utilisation  of,  904 

albumen,  manufacture  of,  904 

boiling  and  drying,  906 

manure,  905 

Bltth,  Mr.  W.,  on  composition  of  black  tea, 

489 
Boating,  adaptability  of,  584 

—  as  an  exercise,  580 

Boats,  mechanical  value  of  sliding-seats  in, 

581 
Body,  development  of  the,  543 

—  method  of  measuring  parts  of,  551 


BUT 

Body,  normal  proportions  of,  549 

—  rate  of  growth  of,  544 
Bone,  proportion  of,  to  meat,  443 

—  -boiling,  nuisance  caused  by,  913 
Bones    and    muscles,   injuries    of,   during 

exercise,  570 

—  distillation  of,  dangers  connected  with, 
969 

—  storage  of,  causing  a  nuisance,  923 
Boots,  points  to  be  attended  to  in,  527 
BouHiN,  M.,  on    lesions  after   death   from 

lightning,  200 
Bourges,  plan  of  artillery  barracks  at,  700 
BowiJiTCH,  Dr.,  on  dampness  of  soil  as  a 

cause  of  phthisis,  358 
BoxALL,  Dr.,  on  management  of  the  General 

Lying-in  Hospital,  HOI 
Boxing  as  an  exercise,  579 
Boyle's    ventilator   and    Baknham's  cowl, 

77 
Boys,  rate  of  growth  and  development  of, 

545 

—  relative  height  of,  under  varying  condi- 
tions, 546 

Bradford,  back-to-back  houses  at,  683 

—  fume-cremator  in  use  at,  810 

—  regulations  for  prevention  of  wool- 
sorters'  disease  at,  932 

—  sewage  treated  by  electrolysis  at,  868 
Brain-symptoms  in  lead-poisoning,  961 
Braxy,   meat   of    animals   suffering   from, 

503 
Bread,  adulterations  of,  464 

—  advantages  of,  as  a  food,  459 

—  aerated  (non-fermented),  459 

—  alum  in,  464 

—  chemical  composition  of,  459 

—  examination  of,  463 

—  manufacture  of,  458 

—  preservation  of,  460 

—  whole  meal,  457 

—  yeast  in  the  manufacture  of,  458 
Breath,  impurities  in  air,  due  to,  13 
Breathlessness,  as  a  result  of  exercise,  560 

—  due  to  excess  of  COj  in  blood,  561 

—  stages  of,  562 

Brickfields,  effects  of  air  from,  12 

Brick-making,  nuisances  arising  from,  940 

Bricks,  porosity  of,  661 

Briegeb  on  symptoms  caused  by  decom- 
posing meat,  445 

Brighton,  water-supply  at,  239 

Bbistowe  and  Holmes,  report  on  hospital 
construction,  722 

Bromine,  nuisances  connected  with  manu- 
facture of,  950 

Brunton,  Dr.  L.,  on  reduction  of  tempera- 
ture by  alcohol,  484 

Buchanan,  Sir  G.,  on  epidemic  typhus  at 
Greenock  (1865),  653 

—  on  moisture  of  soil  in  connection  with 
phthisis,  356,  660 

results  of  sanitary  work,  891 

ventilation  of  pipe-sewers,  846 

Buckwheat  as  a  food,  468 

Bucquoy,  M.,  on  the  circulation  in  workers 

in  compressed  air,  195 
Buda-Pesth,  epidemics  of  typhoid  at,  835 
Businesses,  offensive  and  noxious,  899 
Butter,  adulterations  of,  437 

3s2 


996 


HYGIENE 


BUT 

Butter,  artificial,  439 

—  composition  of,  437 

—  examination  of,  437 

—  foreign  fats  in,  438 

BuTTERFncLD,  Mr.,  on  cottage  privies  and 
summer  diarvhanx,  (iSl 


Cadge,  Mr.,  on  prevalence  of  calculus,  379 
Caffein,  physiological  action  of,  488 
Calcium  and  magnesium,  value  of,  in  food, 
400 

—  salt^  of,  in  water,  259 
Calculus,  causes  of,  380 

—  deaths  from,  in  England,  379 

—  geographical  distribution  of,  378 

—  immunity  of  Ireland  from,  379 
Calisthenic  exercises,  5!)4 

'  Calorie,'  meaning  of  term,  35 
Cancer  as  related  to  conditions  of  soil,  377 
Canoeing  as  an  exercise,  585 
Carbo-hydrates  as  food,  395,  399 
Carbon,  amount  of,  in  diets,  405 

—  dioxide,  conditions  modifying  excretion 
of,  14 

morbid  effects  of  inhalation  of,  945 

treatment  of  poisoning  by,  945 

—  disulphide,  vapour  of,  in  air,  10 

—  — ground  air,  318 

—  elimination  of,  increased  by  exercise,  555 
Carbonates  in  the  body,  sources  of,  401 
Carbonic  oxide  and  carbon  dioxide,  differ- 
ences in  symptoms  of  poisoning  by,  944 

morbid  effects  of  inhalation  of,  939 

treatment  of  poisoning  by,  944 

Carcases  of  animals,  modes  of  dressing,  497 
Caenelley   and   Mackie  on  estimation  of 

oxidisable  substances  in  air,  26 
Caenelley,    Haldane,    and   Andeeson  on 

carbon  dioxide  in  air,  4 
micro-organisms    in   air   of 

rooms,  16 
organic   matter   in   expired 

air,  15 
standard  of  purity  of  air,  18, 

21 

—  on  cost  and   efficiency  of   heating  and 
ventilating  schools,  142 

—  determination    of    amount    of    iron   in 
water,  293 

Carpentek,  Dr.  A.,  on  absence  of  risk  from 

sewage-farms,  12 
crop  of  rye  grass  from  sewage- 
farms,  878 
Carpet-cleaning,  nuisance  caused  by,  925 
Caere's  apparatus  for  cooling,  139 
Cabsten,  Dr.,  on  prevention  of  trichinosis, 

499 
Caetee,  Dr.  v.,  on  prevalence  of  calculus, 

381 
Catch-water  system  at  sewage-farms,  876 
Catgut-making,  nuisance  caused  by,  904 
Catheters,  methods  of  disinfection  of,  792 
Cattle,  importation  and  transport  of,  977 

—  vessels  carrying,  978 
Cellar  dwellings,  rules  for,  688 
Cell:  on  plasvioclnmi  malarics,  352 
Cereals  as  food,  455 

Cesspools,  construction  and  dangers  of,  823 

—  Continental  systems  of,  824 


CLI 

Cesspools,  history  of,  and  laws  regarding,  822'. 

—  pollution  of  wells  by,  823 

—  radical  objections  to,  824 
Chamrerlain-Pasteur  filter,  advantages  of,. 

254 
Charcoal  closets,  817 

—  use  of,  in  filters,  254 
Cheese,  adulterations  of,  440 

—  as  an  article  of  diet,  439 

—  bad  effects  of,  440 

—  composition  of,  439 

Chenopodium  cjiiiiioa  as  an  article  of  food,. 

469 
Chest-girth,  average,  in  males,  546 

—  exercises  tending  to  develoj),  611 

—  importance  of  full  development  of,  548 

—  increase  of,  caused  by  exercise,  548 
Chestnuts  as  food,  469 

Childhood,  diet  requisite  for,  407 
Children,  hospitals  for,  744 

—  management  of,  in  gymnasia,  600 

—  rules  for  physical  education  of,  606 

—  selection  of  exercises  for,  611 
Chimney  flues,  size  of,  for  different  rooms, 

126 
Chimneys,  points  in  construction  of,  97 
Chlorine,  morbid  effects  of  inhalation  of,. 

939,  951 

—  in  water,  estimation  of,  278,  304 
Cholera,  Asiatic,  in  warm  climates,  207 

—  bacillus  of,  344 

—  from  contamiiration  of  soil,  339 

—  infantum,  conditions  influencing  preva- 
lence of,  364 

—  outbreak  of,  in  Soho,  268 

—  practical  extinction  of,  in  England,  894 

—  propagation  of,  through  water,  267 
Chromium,  dangers  to  workers  in,  953 

—  detection  of,  in  water,  294 
Chezonsczewsky     on     absorption    by    the- 

skin,  628 
Churches,    heating    surface    required    for- 
warming,  137 

—  used  as  hospitals,  mortality  in,  720 
Circulation  and  respiration,  effects  of  cold' 

baths  upon,  622 
Cirro-cumulus  and  cirro-stratus,  178 
Cirrus,  177 
Cisterns,  construction  of  and  materials  for,. 

247 

—  for  storage  of  water  in  dwellings,  666 

—  necessity  for  regular  cleansing  of,  667 

—  to  supply  closets,  667 

Civilisation,    drawbacks     connected    with,, 

539 
Clark,  Dr.,  on  testing  hardness  of  water,, 

258 
process  for  estimating  hardness 

of  water,  290 
Climate,    as    influenced    by     atmospheric 

electricity,  199 

barometric  pressure,  192,  202 

humidity,  189 

rainfall,  191 

temperature,  188 

winds,  196 

influencing  diet,  407 

prevalence  of  calculus,  380 

—  British,  216 

—  factors  constituting,  188 


INDEX 


997 


CLI 

•Climate,  influence  of,  on  health,  187 
■Climates,  classification  of,  200,  208 

—  cold,  215 

—  effects  of  latitude  u^Don,  201 
■ —  marine,  216 

—  mountain,  220 

—  of  deserts,  210 

—  temperate,  213 

diseases  prevailing  in,  214 

—  warm,  203 

diseases  prevailing  in,  204 

Climbing,  apparatus  for,  in  gymnasia,  604 
Closet  accommodation  in  schools,  712 
Closets,  ashes  for  use  in,  816 

—  charcoal,  817 

—  construction  of,  815 

—  earth,  818 

Clothing,  absorbent  power  of,  519 

—  ffisthetic  aspects  of,  533 

—  articles  of,  for  the  feet,  526 

—  boots  as  articles  of,  527 

—  coats  and  waistcoats  as  articles  of,  523 

—  cotton  as  a  maierial  for,  513 

—  flannel  as  a  material  for,  522 

—  flax  as  a  material  for,  514 

—  for  the  head,  kinds  of,  520 

—  forms  of,  for  exercise,  525 

—  fur  as  a  material  for,  511 

—  india-rubber  as  a  material  for,  515 

—  kind  and  colour  of,  for  resisting  heat, 
519 

—  kinds  of,  for  resisting  wind  and  cold, 
518 

—  leather  as  a  material  for,  513 

—  materials  used  for,  509 

—  methods  of  fire-proofing,  535 

testing  quality  of,  516 

water-proofing  and  cleansing,  534 

—  of  hospital  patients,  care  of,  786 

—  principles  of,  for  women,  525 

—  shoes  as  articles  of,  529 

—  silk  as  a  material  for,  510 

—  thermal    conductivities    of    articles  of, 
518 

—  trousers   and  knee-breeches  as  articles 
of,  524 

—  uses  of,  509,  621 

—  weight  of,  532 

—  wool  as  a  material  for,  509,  517 
Cloud,  amount  and  forms  of,  177 
Clouston,  Dr.,  on  dysentery  caused  by  sew- 
age, 368 

Coal-gas,  composition  of,  946 

—  effects  of  escape  and  inhalation  of,  948 

—  nuisances  connected  with  manufacture 
of,  946 

Coats  and  waistcoats,  points  desirable  in, 

523 
CoBBOLD,  Dr.,  on  effects  of  sewage  irrigation 

on  health  of  cattle,  886 
Coca,  effects  of,  399 
Cocoa,  composition  and  action  of,  491 
Ccenurus  cerebralis  in  meat,  498 
Coffee,  composition  of,  490 

—  physiological  action  of,  488 
Cold,  effects  of  exposure  to,  188 

local  application  of,  624 

Colostrum,  composition  of,  428 
Combustion,  impurities  in  air,  due  to,  15 
Comeliness,  effect  of  exercise  upon,  556 


DEV 

Comfort,  bodily,  as  caused  by  exercise,  558 
Comma  bacillus  and  Asiatic  cholera,  344 
Concrete,  sites  of  dwellings  to  be  covered 

with,  660 
Condiments  as  food-accessories,  479 
Conservancy,   comparison   of    systems   of, 

826 

—  systems  of,  812 
Consumption  hospitals,  744 
Convalescent  hospitals,  744 
Cooling,  artificial,  139 

Copper,  detection  of,  in  water,  290 
CoitFiELD,  I'rof.,  siplion  trap  devised  by,  769 
Corrosive  sublimate,  spray  containing,  for 

treatment  of  wounds,  789 
Cotton,  as  a  material  for  clothing,  513 
CouLiEK  and  Hammonb  on  conducting  powers 

of  different  materials,  517 
Cow,  composition  of  milk  of,  428 

—  disease  of,  as  affecting  milk,  431 

—  quantity  of  milk  supplied  by,  434 
Cream,  composition  of,  43G 

—  estimation  of,  in  milk,  435 
Ceookshank,  Dr.,  on  cultivation  of  micro- 
organisms in  water,  297 

Crops  best  suited  for  sewage  farms,  878 
Croydon  sewage  farm,  system  at,  876 
Cubic  space  per  head,  amount  of,  required 

in  rooms,  20 

measurement  of,  21 

CuLLiNGWORTH,  Dr.,  on  results  of  antisepti- 

cism  in  lying-in  hospital,  800 
Cumberland  asylum,  epidemic  of  dysentery 

in,  368 
Cumulus  and  cumulo-stratus,  178 
Cunningham's  blowing  machine,  81 
CuRKiE,   Dr.,   on  effects  of   cold  baths  in 

fevers,  618,  631 
Cycles,  forms  of,  586 
Cycling,  as  an  exercise,  588 

—  for  girls  and  ladies,  drawbacks  to,  593 

—  objections  urged  against,  589 

—  precautions  regarding,  591 

—  troubles  alleged  to  be  caused  by,  590 
Cysticercus  cellulosce  in  meat,  446 
of  beef,  447 


Damp-pkoof  courses  in  buildings,  661 
Dabwin,    H.,    instrument    for    measuring 

differences  of  pressure,  107 
Davaine  on  anthrax  bacillus,  376 
Davies,  Dr.  A.  M.,  on  naked-eye  characters 

of  colonies  of  bacteria,  29 
De  Chaumont,  Prof.,  on   CO.^  in  air  as  a 

standard  of  impurity,  17 
position  of  inlets  for  hospital 

wards,  120 
relation  between   ah  required 

and  initial  cubic  space,  116 

standard  of  purity  of  air,  23 

suspended  matters  in  au%  5 

wells   affected  by  nearness  to 

sea,  238 
De  Laune,  on  plague  in  London  (1665),  651 
Dengue,  in  warm  climates,  207 
Deserts,  climates  of,  210 
Dessau,  lead-poisoning  from  water  at,  257 
Development,    bodily,  effects    of    exercise 

upon,  542 


998 


HYGIENE 


DIA 

Diaphoresis,  means  of  producing,  639 
Diarrhoea,  as  related  to  soil,  362 
^  attacks  of,  due  to  effluvia,  12 

—  conclusions  as  to  causes  of,  366 

—  due  to  drinking  water,  271 

—  mortality  from,  in  Buffalo,  U.S.,  364 
London  (table),  365 

—  prevalence  of,  as  affected  by  density  of 
population,  657 

DiBDiN,   Mr.,   on    composition    of    sewage 

sludge,  862 
Diet  and  dietaries,  404 

—  conditions  affecting,  404 

—  effects  of,  on  character  of  fteces,  412 

—  influence  of  age  and  climate  on,  407 
constitution  and  work  on,  407 

—  nitrogenous  and  non-nitrogenous  food- 
stuffs in,  408 

—  proportion  of  fat  to  carbo-hydrates  in, 
409 

foodstuff's  in  articles  of,  411 

Diets,  adapted  for  rest,  404 
for  work,  405 

—  amount  of  carbon  and  hydrogen  in,  405 
foodstuff's  in  417 

—  construction  of,  410 

—  for  soldiers  and  sailors,  414 

—  in  prisons  and  workhouses,  416 
■ —  of  the  working  classes,  415 

—  salts  and  water  of,  406 

—  special,  413 

—  standard,  estimation  of,  404 
Digestion,  as  aft'ected  by  alcoholic  stimu- 
lants, 477 

Dines'  hygrometer,  166 

Dip-candle  making,  nuisance  due  to,  910 

Diphtheria,  bacillus  of,  339 

—  from  air  vitiated  by  sewage  emanations, 
12 

contamination  of  soil,  337 

—  increasing   prevalence   of,  in   England, 
895 

Diseases  attributed   to   conditions  of  soil, 
331 

—  caused  by  food,  424 
meat,  444 

Disinfection,  aerial,  in  isolation  wards,  795 
Distoma  heimticwn  in  meat,  498 
Divers,  eft'ects  of  occupation  upon,  195 
Dormitories  in    schools,  arrangements  of, 
709 

cubicle  system  in,  710 

Drains,  best  forms  of,  765 
■ —  defects  of,  764 

—  examination  and  testing  of,  776 

—  fall  or  inclination  of,  766 

—  flushing  of,  772 

—  foundation  of,  765 

—  functions  of,  764 

—  gulley-traps  for,  770 

—  man-hole  for,  768 

—  methods  of  connecting  pipes  of,  765 

—  plans  of  laying,  767 

—  size  of  pipes  in,  766 

—  tests  for,  768 

—  traps  for,  769 

—  waste-pipes  cut  off  from,  771 
Dress,  ffisthetic  aspects  of,  533 
Dressings,  boxes  and  tables  for,  in  hospitals, 

788 


DWE 

Drilling  as  a  part  of  gymnastics,  596 
Drinking-water,  good,  characters  of,  298 
Drugs,  dissolved,  question  as  to  cutaneous 

absorption  of,  628 
Dujabdin-Beadmetz  on  impurities  in  alco- 
holic drinks,  486 
Dukes,  Dr.  C,  on  school  dormitories,  709 
Dumb-bells,  use  of,  in  gymnastics,  601 
Dung-heaps,  nuisances  arising  from,  923 
DuPRK,  Dr.,  on  action  of  water  on  lead,  257 

—  and  Haice,  detection  of  organic  matter 
in  water,  284 

modification  of  Frankland's  me- 
thod of  estimating  organic  matter  in 
water,  283 

Dust  and  smoke  in  air,  48 

—  conditions  checking  or  favouring  accu- 
mulation of,  50 

—  estimation  of  number  of  particles  of,  in 
air,  49 

—  in  mines  and  factories  as  a  cause  of 
lung-disease,  7 

Dwellings,  back-to-back,  faults  of,  682 
tubercular  disease  in,  684 

—  blocks  of,  defects  in,  679 

—  cellar,  rules  for,  688 

—  cisterns,  use  of,  in,  666 

—  classification  of,  in  United  Kingdom, 
657 

—  combined  with  shops,  &c.,  671 

—  common  lodging-houses  as,  685 

—  concrete  for  covering  sites  of,  660 

—  conditions  necessary  for  healthfulness 
of,  651 

—  construction  of  roofs  of,  662 

• —  cottage,  defective  closet-accommodation 

in,  681 
faulty  sites  for,  682 

—  dampness  of,  as  related  to  diphtheria, 
338 

—  damp-proof  courses  in,  661 

—  defective  drainage  in  large,  668 

—  defects  in  ordinary,  670 

—  designed  for  wage-earning  classes,  673 

—  drainage  of,  764 
plans  for,  767 

—  drain-pipes  for,  position  of,  767 

—  evils  of  crowding,  on  confined  areas,  653 

—  external  walls  of,  661 

—  for  agricultural  labourers,  676 
— •  —  artisans,  677 

in  metropolis,  656 

working  classes  in  France,  675 

—  height  of,  as  influencing  health,  657 

—  hygiene  of,  connected  with  density  of 
population,  656 

—  increase  of,  in  recent  years,  658 

—  light  and  ventilation  of,  663 

—  model,  death-rate  in,  680 

—  necessary  conditions  in  construction  of, 
659 

—  protection  of,  from  ground-exhalations, 
659 

—  removal  of  solid  and  liquid  refuse  from, 
663 

—  rooms  in,  heating  surface  required  for 
warming,  138 

—  storage  and  distribution  of  water  in, 
666 

—  used  as  institutions,  689 


V 

I 


INDEX 


999 


DWE 


Dwellings,  water-closets  suitable  for,  664 
Dysentery,  diarrhoea,  and  tropical  abscess 
of  liver,  208 

—  due  to  drinking-water,  272 

—  prevalence  of,  as  affected  by  soil,  367 


Ealing,  refuse-destructor  and  fume-cre- 
mator in  use  at,  810 

Earth  closets,  818 

arrangements  for,  in  schools,  713 

soil  from,  as  manure,  819 

Easton,  Mr.,  on  utilisation  of  water  passing 
through  chalk,  239 

Education  Department,  rules  of,  for  space, 
&c.,  in  schools,  707 

Eggs  as  articles  of  diet,  440 

—  composition  of,  441 

—  digestibility  of,  441 

—  storage  of,  causing  a  nuisance,  924 
Egypt,  climate  of,  210 

Eheenbeeg  on  microscopical  examination 
of  dust-showers,  5 

EisELBEKG  on  relation  of  tetanus  to  soil, 
375 

Electricity  as  a  method  of  depositing  dust- 
particles,  51 

—  atmospheric,  as  influencing  climate,  199 
Electrolysis,  sewage  precipitated  by,  868 
Emphysema,  treatment  of,  by  compressed 

air,  644 
Endurance,  exercises  involving,  610 
Energy,  expended  by  body,  estimation  of, 

401 
England,  deaths  from  urinary  calculus  in, 

379 
Epidemics  in  towns,  lessons  to  be  gathered 

from,  652 
Ergot  of  rye,  symptoms  due  to,  467 
Ekichsen,  Prof.  J.  E.,  on  the  '  big-house  ' 

plan  of  hospitals,  722 
Erysipelas,  effects  of  Listerism  in  diminish- 
ing, 799 
Examination  of  drains,  methods  of,  766 
Excreta,  human,  quantity  and  composition 

of,  810 

—  the  pail  system  for  removal  of,  814 

—  water-carriage  system  for  removal  of, 
827 

Exercise,  boating  as  a  form  of,  580 

—  boxing  as  a  form  of,  579 

—  cycling  as  a  form  of,  586 

—  effects  of,  on  accumulation  of  fat,  554 

—  blood-current,  561 

—  development,  542 

elimination  of  carbon,  555 

kidneys,  556 

muscular  and  nervous  systems, 

552 

personal  comeliness  and  com- 
fort, 556 

tissues   and   organs  generally, 

553 

—  excessive~or  unsuitable,  effects  of,  567 

—  fencing  as  a  form  of,  578 

—  forms  of,  610 

for  children,  611 

girls  and  women,  612 

males  at  various  ages,  613 


FLO 

Exercise,  gymnastics   and   calisthenics   as 
forms  of,  59.3 

—  jumping  as  a  form  of,  595 

—  mental  and  moral  effects  of,  558 

—  outdoor  games  as  forms  of,  605 

—  riding  as  a  form  of,  577 

—  rules  for  conducting  forms  of,  600 

—  running  as  a  form  of,  574 

—  skating  as  a  form  of,  576 

—  specific  forms  of,  .^72 

—  systematised,  effects   of,  on   circumfer- 
ence of  chest,  548 

development    and   growth, 

547 

—  walking  as  a  form  of,  573 

Exertion,  physical,  natural  craving  for,  541 
Exhalations  from  the  sick,  effects  of,  11 


Fabbics  for  clothing,  modes  of  testing,  516 
Fffices,  character  of,  as  influenced  by  diet, 

412 
Fans,  for  the  production  of  ventilation,  77 
Fat,  removal  of,  by  exercise,  554 
Fat-melting,  nuisance  due  to,  910 

—  bye-laws  regulating,  911 

Fatigue,  breathlessness  as  a  sign  of,  500 

—  general,  566 

—  muscular,  explanation  of,  564 

—  phenomena  of,  560 

Fats,  amount  of,  in  meat,  443 

—  as  food,  395,  399 

Faybee,  Sir  J.,  on  cause  of  monsoons,  197 

malaria,  209 

subsoil  water  as  a  condition  of 

malaria,  209 

•  sunstroke,  205 

Feet,  articles  of  clothing  for,  525 
Fellmongering,  nuisance  caused  by,  915 
Fencing,  as  an  exercise,  578 
Fever,  as  a  symptom  of  over-exertion,  566 

—  effects  of  cold  baths  upon,  620,  631 
Field,  Mr.  Eogers,  flushing  siphon  devised 

by,  772 

siphon  trap  devised  by,  769 

File-cutters,     danger     of      lead-poisoning 

among,  962 
Filter-beds,  construction  of,  252 
Filters,  materials  used  for,  251 

—  household,  materials  suitable  for,  254 
Filtration,  on  large  scale,  251 
Fire-grates,  for  increasing  radiation,  124 
Fire-proofing,  recipes  for,  535 

Fish,  as  an  article  of  food,  444 

—  frying,  nuisance  due  to,  907 

—  injury  to,  by  effluent  sewage,  865 

• —  part  played  by,  in  purifying  water,  851 

—  storage  of,  causing  nuisance,  923 
Flannel,  as  a  material  for  clothing,  522 
Flats,  residential,  sanitary  condition  of,  670 
Flax,  as  material  for  clothing,  514 
Flesh,  as  an  article  of  food,  441 

—  boiling,  nuisance  caused  by,  902 
Floating  hospitals,  for  infectious  diseases, 

752 

small-pox  cases,  753 

Floors    of    hospitals,    materials    for,   and 

cleaning,  779 
Flour,  wheaten,  456 
adulterations  of,  462 


1000 


HYGIENE 


Flour,  wheaten,  amount  of  gluten  in,  461 

examination  of,  461 

parasites  in,  462 

preparations  of,  458 

Flues,  position  of,  for  ventilation,  118 
Flugge  on  micro-organisms  in  soil,  314 
Flukes,  in  sheep's  liver,  447 
Fodder,  peculiarities  of,  as  affecting  meat, 

445 

milk,  444 

FoDOR,  on  action  of  micro-organisms  in  soil, 

315 

amount  of  moisture  in  soil,  325 

moisture   in   soil    and   diffusion   of 

cholera,  343 

nitrification  of  soil,  313 

temperature  of  soil,  327 

typhoid  at  Buda-Pesth,  335 

Fogs,  method  of  recording  density  of,  179 
Food-accessories,  474 

aromatic  principles  as,  475 

as  stimulating  digestion,  476 

secretions,  476 

classes  of,  475 

nervine  stimulants  and  sedatives  as, 

475 

retarding  effect  of,  on  digestion,  479 

taken  as  liquids,  480 

variations  in  action  of,  477 

Food,  animal,  427 

effects  of  cooking  upon,  422 

large  quantities  of,  399,  424 

—  articles  of,  426 

—  bulk,  and  reaction  of,  as  affecting  diges- 
tion, 420 

—  daily  arrangement  of,  in  meals,  417 

—  definition  and  uses  of,  393 

—  digestibility  of,  418 

—  diseases  caused  by,  424 

—  eft'ects  of  diminution  of,  425 
excess  of,  424 

—  inorganic  constituents  of,  400 

—  perfect,  milk  as  a  type  of,  410 

—  preparation  of,  421 

—  proximate  principles  of,  393 

—  variety  of,  desirable,  479 

—  vegetable,  449 

classification  of,  455 

composition  of,  450 

—  ■ —  effects  of  cooking  upon,  422 

—  • —  preparation  of,  450 

proteids  in,  450 

uses  of,  449 

Foodstuffs,  carbo-hydrates  as,  395 

—  change  of,  in  the  body,  396 

—  classification  of,  393 

—  construction  of  diets  with,  410 

—  differences  in  nutritive  value  of,  403 

—  fats  as,  396 

—  inorganic,  396 

—  isodynamic,  402 

—  nitrogenous,  393 

and  non-nitrogenous  in  diet,  408 

composition  of,  394 

—  non-nitrogenous,  organic,  395 

—  nutritive  value  of,  401 

—  potential  energy  of,  402 

—  proportions  of,  in  articles  of  diet,  411 

—  proteid-sparing,  398 

—  vegetable  acids  as,  396 


GOL, 

Foot-and-mouth  disease  affecting  meat,  501 

milk,  432 

Football,  value  of  game  of,  606 
Form,  female,  proportions  of,  550 
FoEsTER    on   proportion  of  fat   to   carbo- 
hydrates in  diet,  409 
water  in  food  before  and  after  cook- 
ing, 423 
Fox.  Dr.,  on  ozone,  179 
Fi;axkl.^d,  Dr.,  on  classification  of  waters 
according  to  organic  purity,  300,  302 

estimation  of  nitrates  in  water,  282 

organic  matter  in  water,  283 

spontaneous  purification  of  rivers, 

242,  264 

—  Dr.  P.,  on  examination  of  micro-organisms 
in  air,  28 

water,  296 

Fr.tDraicQ   and   Quinquand   on   effects   of 

application  of  cold,  620 
French  schools,  rules  for   dormitories   in, 

709 
Frey    and    Heiligenthal    on    effects    of 

Piussian  baths,  640 

Turkish  baths,  638 

Friction  of  air  in  tubes,  losses  by,  64,  66 
Friends,  visits  of,  to  patients  in  hospitals, 

785 
Fruit    and   vegetables,    nuisances    arising 

from,  924 
Fruits,  composition  of,  472 
Fuel,  heat  developed  by  various  kinds  of,  122 

—  waste  of,  in  open  fireplaces,  123 
Fur,  as  a  material  for  clothing,  511 


Games,  outdoor,  value  of,  605 

Gas  fires  and  stoves  for  warming,  128 

Gases,  diffusion  of,  in  air,  45 

—  in  water,  question  as  to  cutaneous  ab- 
sorption of,  618 

—  irrespirable,  morbid  effects  from,  937 
Gateshead   Union,   plan  of  workhouse  of, 

718 
Gelatine  as  an  article  of  food,  398 
Girls  and  women,  selection  of  exercises  for, 

612 

—  rate  of  growth  and  development  of,  545 
Gladstone   and    Tribe    on     detection    of 

nitrates  in  water,  281 
Gl-usher    and    Coswell,    experiences     of 

balloon  ascent,  193 
Glaisher's  thermometer  stand,  169 
Glasgow  University,  heating  and  ventilation 

of,  146 

—  water  supply  of,  232 

Glass-cutters,     danger     of    lead-poisoning 

among,  962 
Globulins  as  articles  of  food,  394 
Glossop,  fatal  cases  at,  due  to  inhalation  of 

coal  gas,  949 
Glue,  nuisance  arising  from  manufacture 

of,  908 
Gluten,  amount  of,  in  flour,  461 
Goitre  and  cretinism,  as  related  to  nature 

of  soil,  381 
associated  with  use  of  hard  water, 

259,  273,  383 
Golf  as  an  exercise,  advantages  of,  574 
GoLGi  on  micro-organisms  of  malaria,  353 


INDEX 


1001 


GOU 

Goux  system  for  removal  of  excreta,  815 
Graham,   Dr.   C,   on   chemistry  of   bread- 
making,  458 

—  Prof.,  on  effects  of  hardness  of  water, 
258 

Gbange  on  magnesian  limestone  soil  and 

goitre,  384 
Granite  as  an  element  of  soils,  310 
Geantham,  Mr.  R.  F.,  on  separate  system  of 

sewage,  836 
Grates,  ventilating,  dimensions  for,  126 
Graveyards,  air  of,  effects  from,  12 
Grease  from   sinks,    methods    of    dealing 

with,  775 

—  nuisance  due  to  recovery  of,  from  soap- 
suds, 909 

Great  Northern  Central  Hospital,  plan  of, 

726 
Gbeenhow,   Dr.,    on    causes    of    epidemic 

diarrhoea,  362 
diphtheria  associated  with  nasal 

diseases  of  cattle,  337 
prevention  of  pulmonary  phthisis, 

355 
Ground  air,  carbon-dioxide  in,  318 

carburetted  hydrogen  in,  320 

composition  of,  318 

currents  of,  322 

— estimation  of  carbon  dioxide  in,  323 

nitrogen  in,  319 

variations  of  carbon  dioxide  in,  321 

—  exhalations,   protection    of    interior   of 
dwellings  from,  659 

—  or  subsoil  water,  325 

—  cholera  connected  with  move- 
ments of,  341 

— malarious     fevers     connected 

with  movements  of,  348 

movements  of,  326 

typhoid  connected  with  move- 
ments of,  336 
Gulf  Stream,  influence  of,  201 
GuUey  traps,  for  surface  water,  770 
Gums,  blue  line  on,  in  lead-poisoning,  960 
Gut-cleaning,  nuisances  due  to,  903 
Gutta-percha,  as  material  for  clothing,  516 
Gymnasia  and  gymnastic  apparatus,  599 

—  home,  605 

—  rules  for  management  of,  600 
Gymnastics  and  calisthenics,  593 

—  cautions  with  regard  to,  600 

—  English  system  of,  594 

—  German  system  of,  595 

—  Swedish  or  Ling's  system  of,  597 


Haglee,   Dr.,  on  outbreak   of  typhoid  at 

Lausen,  270 
Hail,  varieties  of  forms  of,  178 
Hair-   and  flock-picking,  nuisance  caused 

by,  925 
Halifax,  back-to-back  houses  in,  683 
Halle,  University  Hospital,  plan  of,  735 
Hand-rings,  use  of,  in  gymnastics,  602 
Hardness  of  water,  258 

alleged  effects  of,  259 

—  as  a  cause  of  calculus,  380 

estimation  of,  290 

Hats,  forms  of,  520 


HOS 

Havilanb  on  cancer  as  related  to  condi- 
tions of  soil,  378 

Hawksley,  Mr.  T.,  on  effects  of  hardness  of 
water,  259 

on  rainfall  available  for  water- 
supply,  232 

Head,  clothing  suitable  for,  520 

'  Head '  in  ventilation,  meaning  of  term,  56 

Head,  proportions  of,  during  growth,  550 

Health,  influence  of  soil  upon,  309 

—  physical,  importance  of,  540 

Heart  and  blood-vessels,  lesions   of,   from 

excessive  exertion,  569 
Heat,  application  of,  for  cleansing  surgical 

instruments,  791 

—  as  a  form  of  energy,  34 

—  clothing  suitable  for  resisting,  519 

—  conduction  of,  36 

—  convection  of,  39 

—  distribution  of,  36,  131 

- —  effects  of  exposure  to,  ISO 

—  formed  in  body,  estimation  of,  401 

—  gain  and  loss  of,  by  soils,  329 

—  latent,  35 

—  loss  of,  conditions  checking  or  favour- 
ing, 40 

—  predisposing  to  tetanus,  374 

—  production  and  measurement  of,  33 
of,  by  friction,  34 

—  quantities  of,  produced  by  combustion 
of  various  fuels,  35 

—  radiation  of,  37 

—  relation  of,  to  bodily  work,  553 

—  specific,  36 

Hehnek  on  determination  of  fatty  acids  in 

butter,  438 
Height,  relative,  of  adults  and  boys  under 

varying  conditions,  546 
Heights,  measurements   of,  by  barometer, 

156 
Hernia,  production  of,  by  violent  exercise, 

571 
Hesse  on  micro-organisms  in  air,  28 
Hetmann  and  Keebs,  on  electrical  oi^erations 

of  baths,  629 
Hides  as  a  source  of  anthrax,  930 

—  nuisances  caused  by  preparation  of,  916 
HiLGEB,  on  melting  points  of  various  fats, 

438 

HiRscH  on  geographical  distribution  of 
calculus,  380 

HiET  on  health  of  workers  in  chlorine, 
939 

Honey,  composition  of,  454 

Horse-slaughtering,  nuisance  due  to,  900 

Horsehair,  nuisance  connected  with  pre- 
paration of,  935 

Hospital  at  Antwerp,  plan  of,  737 

—  - —  Halle,  plan  of,  735 

—  —  Lincoln,  plan  of,  740 

—  for  infectious  diseases  at  Leamington, 
760 

—  ■ Newcastle,  750 

—  Great  Northern,  plan  of,  726 

—  Guy's,  results  of  Listerism  on  erysipelas 
in,  799 

—  Moabit,  Berhn,  plan  of,  739 

—  St.  Denis,  Paris,  plan  of,  740 

—  St.  George's,  statistics  of  amputations 
in,  798 


1002 


HYGIENE 


HOS 

Hospital,  workhouse,  plans  of,  742 
Hospitals,  amount  of  water  necessary  for, 
245 

—  at  York  and  Manchester,  defects  in,  721 

—  classification  of,  722 

—  cleaning  of  floors  of,  779 

—  contamination  of  air  of,  719 

—  cottage,  743 

—  cubic  space  per  head  required  in,  20 

—  dangers  to  patients  in,  719 

—  defects  in  construction  of,  719 

—  fissures  in  floors  of,  780 

—  hygiene  of,  779 

—  improper  arrangements  of  buildings  of, 
722 

—  materials  for  floors  of,  779 

—  necessity  for  speedy  removal  of  excreta, 
&c.,  from,  721 

—  position  of  inlets  for  wards  in,  120 

—  purity  of  air,  a  necessity  in,  720 

—  purposes  for  which  constructed,  718 
results  of  improved  hygiene  in,  796 

—  ventilation  and  warming  of,  761 
artificial  in,  762 

of  small-pox,  763 

various  systems  of,  762 

—  general,  administration  oflices  of,  725 

—  —  arrangements  of  essential  parts  of, 
724 

balconies  in,  732 

bath-rooms  in,  732 

care  and  cleansing  of  instruments  in, 

790 

care  of  patients'  clothing  in,  786 

circular  wards  in,  728 

cleaning  of  bedding  in,  782 

cooking  arrangements  in,  794 

dresses  of  attendants  in,  783 

dresses  of  surgeons  performing  opera- 
tions in,  784 

examples  of  plans  of,  735 

floor  and  cubic  space  in,  727 

form  of  wards  in,  728 

isolation  wards  in,  794 

lockers  for  patients'  necessaries  in, 

786 

materials  for  floors  of,  731,  779 

walls  of,  730 

raovtnarj  a.n6.  post-mortem  rooms  in, 

738 

nurses'  rooms  in,  731 

open  space  around,  723 

operation  rooms  in,  732 

ornaments  for  walls  of,  781 

out-patient  department  of,  733 

rectangular  pavilion  wards  in,  729 

site  area  of,  per  bed,  723 

sites  for,  723 

size  of  wards  of,  727 

statistics  of   amputations  in,   before 

and  after  Listerism,  798 

tables  and  boxes  for  dressings  in,  788 

ventilation  of,  727,  761 

—  -—  visits  of  friends  to  patients  in,  785 
walls  of,  781 

ward  offices  in,  731 

water-closets  for  patients  in,  731 

windows  in  wards  of,  730 

—  special,  744 
children's,  744 


JOH 

Hospitals,  special,  consumption,  744 

convalescent,  744 

floating,  for  infectious  diseases,  752 

for  infectious  diseases,  745 

isolation  blocks  in,  747 

open  space  around,  749 

■ plans  and  types  of,  746 

small-pox,  dangers  of,  753 

i-ecommendations  for,  753 

the  insane,  754 

lying-in,  745 

details  of  management  of,  801 

results  of  antisepticism  in,  800 

ophthalmic,  744 

Hotel-Dieu,    Paris,    condition   of,    in   last 

century,  719 
Hotels,  inns,  etc.,  sanitary  conditions  and 

defects  in,  673 
House  drains,  pipes  for,  834 
Houses,  back-to-back,  defects  of,  683 

—  of  ParUament,  ventilation  of,  145 

—  overcrowding  of,  as  a  cause  of  disease, 
652 

Housing  of  working  classes,  Acts  relating  to, 

674 
Howard,  John,  on  condition  of  prisons  in 

last  century,  690 
Humidity  as  influencing  climate,  189 
Hydatid  disease,  production  of,  447 
Hydrochloric    acid   vapours,  efl'ects   of,  in 

air,  10 
Hydrogen-sulphide,  effects  of,  in  air,  10 
Hygrometer,  Dines',  166 

—  Saussuee's,  166 
Hygrometi'y,  164 


Ice,  machines  for  artificial  production  of, 

139 
Immisch's  thermometers,  163 
India,  effects  of  climate  of,  on  Europeans, 

187 
India-rubber  as   a  material   for   clothing, 

515 

—  nuisance  connected  with  manufacture  of, 
930 

Indian  clubs,  use  of,  in  gj'mnastics,  601 

Infectious  diseases,  hospitals  for,  746 

Infirmaries  for  schools,  755 

Inlets  and  outlets,  position  of,  for  ventila- 
tion, 118 

Insane,  asylums  for,  754 

Instruments,  care  and  cleansing  of,  in  hos- 
pitals, 790 

Iodine,  nuisances  connected  with  manufac- 
ture of,  950 

Ireland,  immunity  of,  from  calculus,  379 

Iron,  estimation  of,  in  water,  293 

—  sulphate,  use  of,  to  precipitate  sewage, 
859 

—  uses  of,  in  food,  401 
Irrigation  of  sewage,  873 
into  subsoil,  886 

—  practice  of,  in  surgical  operations,  789 


Jaws,  necrosis  of,  caused  by  phosphorus, 

969 
Johnson's    filter    press    for    dealing   with 

sewage,  861 


INDEX 


1003 


JON 

Jones,  Mr.,  Destructor  and  fume  cremator 

furnace  for  refuse,  etc.,  810 
Joule,  J.  P.,  on  dynamical  cooling  of  air, 

43 
Jumping  and  skipping  as  forms  of  exercise, 

575 


Kelly,  Dr.,  on  connection  between  drainage 

and  phthisis,  359 
Khamseen,  the,  a  kind  of  wind  in  Egypt, 

211 
KiTiSATO  on  the  bacillus  of  tetanus,  372 
Kjbldahl  on  estimation  of  organic  matters 

in  water,  285 
Klebs    and   Tommasi-Crudeli  on   bacillus 

malarise,  209,  351 

of  diphtheria,  339 

Klein,  Dr.,  on  comma  bacillus,  345 

—  detection  of  micro-organisms  in 

water,  297 
Knackeries,  nuisances  due  to,  900 
Knapsacks,  forms  of,  533 
Knotx  on  fever  of  over-exertion,  566 
Koch  on  bacillus  tuberculosis,  36C 
examination  of  micro-organisms  in 

air,  28 

significance  of  comma  bacillus,  344 

spores  of  anthrax,  931 

Kohl  on  Eussian  baths,  640 

Kola,  effects  of,  399 

KoNiG  on  composition  of  various  kinds  of 

meat,  442 

daily  diet  for  children,  408 

proportion  of  foodstuffs  in  articles  of 

diet,  411 
Koumiss  and  Kiphir,  433 
Keause  on  cutaneous  absorption  of  water, 

627 

Ladders,  various  forms  of,  used  in  gym- 
nastics, 603 

Lads,  selection  of  exercises  for,  613 

Lagrange,  Dr.,  on  effect  of  exercise  on 
tissues,  553 

exercises  which  develop  the  chest, 

611 

—  • —  phenomena  of  fatigue,  560 

Lakes,  characteristics  of  water  stored  in, 
234 

Landois,  Prof.,  on  cause  of  local  muscular 
fatigue,  565 

Lariboisi^re  Hospital.  Paris,  ventilation  of, 
762 

Latham,  Mr.  B.,  on  construction  of  sewers, 
831 

effect  of  pumping  out  ground- 
water, 288 

Laundries  for  residential  schools,  714 

Lausen,  Switzerland,  outbreak  of  typhoid 
at,  270 

Lavatories  in  schools,  710 

Lawes  and  Gilbert,  on  percentage  compo- 
sition of  wheat-grain  ash,  457 

Lead,  action  of  water  on,  256,  668 

on,  by  various  matters  in  water,  256 

—  dangers  to  workers  in,  958 

—  detection  of,  in  water,  290 

—  determination  of  action  of  water  upon, 
295 


LUN 

Lead  in  water,  256 

—  prevention  of  water  from  dissolving,  248, 
258 

—  symptoms  of  poisoning  by,  959 

—  trades  in  which  danger  of  poisoning  by, 
962 

—  poisoning,  prevention  of,  as  related  to 
condition  of  soil,  369 

sanitary  precautions  against,  965 

Leamington,  hospital  for  infectious  diseases 

at,  750 
Leather-making,  nuisance  caused  by,  915 
Leeds,  back-to-back  bouses  in,  683 
Leek  Workhouse,  diarrhoea  at,  due  to  water, 

271 
Leguminosse,  seeds  of,  as  articles  of  food, 

469 

digestibility  of,  469 

Leichtenstein,  on  effects  of  salts  and  gases 

in  water,  629 

— warm  baths-,  635 

loss  of  heat  caused  by  cold  baths, 

621 
Lemon    and    lime-juice,    composition    of, 

473 

value  of,  472 

Lewis  and  Cunningham  on  carbon-dioxide 

in  ground  air,  318,  323 
—  ground-water  and   spread  of 

cholera,  341 

— temperature  of  soil,  328,  330 

Liebenbeeg  on  gain  and  loss  of  heat  by 

soils,  329 
Liebeemeister  on  effects  of  cold  baths,  621 
Lieenur's  system  of  sewage,  849 
Lighting  and  ventilation  of  dwellings,  663 
Lightning,  effects  of,  200 
Limbs,  proportions  of,  during  growth,  550 
Lime,  use  of,  to  precipitate  sewage,  858 
Lime-burning,  nuisances  arising  from,  942 
Lincoln  County  Hospital,  plan  of,  740 
Ling,  system   of  gymnastics   founded   by, 

598 
Linoleum,  nuisance  and  dangers  connected 

with  manufacture  of,  926 
Lister,    Sir  J.,  improvements  in  hospital 

hygiene  due  to,  797,  800 
Liverpool,  arrangements  for   abattoirs  at, 

988 

—  licences  for  private  slaughter-houses  in, 
985 

Lockers  for  hospital  use,  786 

LocKWOOD,  Mr.,  on  tetanus  produced  by  in 

oculation,  373 
Lodge,  Dr.  0.  J.,  on  dust-particles  in  aii', 

48 
Lodging-houses,    common,   provisions  for 

control  of,  685 

definition  of,  by  law,  686 

Local   Government    Board    rules 

for,  686 
Lodgings,  houses  let  in,  rules  for,  688 
Lolium  tevudentum  (darnel),  effects  of,  in 

bread,  463 
London,  amount  of  water  supplied  to,  244 

—  mortality  in  1600-1800,  890 

—  regulations  for  private  slaughter-houses 
in,  986 

Lungs,    affections    of,   caused    by  violent 
exercise,  570 


1004 


HYGIENE 


LUN 

Lungs,    deaths   from   diseases   of,    among 

miners,  6 
Lying-in  hospitals,  745 


Macalistek,    Dr.,   on    effect    of     cold    on 

muscles,  620 
Macaroni,  composition  of,  460 
Macdoxald,  Dr.   J.   D.,    on   microscopical 

examination  of  drinking-water,  276 
Machines  for  production  of  cooling,  139 
M.\CL.\KEN  on  growth  of  hoys,  545 
increased   development  as  result  of 

exercise,  548 

system  of  measurements,  551 

Maclean,  Dr.,  on  development  of  malaria 

at  Hong  Kong,  350 
MACLEOD    and    Miller     on     the     cholera 

bacillus,  344 
MacLintock,  Dr.,  on  treatment  of  sewage 

by  electrolysis  at  Bradford,  868 
Macnamaba,  Dr.,  on  connection  between  rain 

and  diffusion  of  cholera,  343 
Magnesian    limestone    in    soil   as   causing 

goitre,  384 
Maize  as  a  food,  467 

—  diseased,  effects  of,  468 

—  starch-grains  of,  454 
Malaria  as  related  to  soil,  347 

—  bacillus  of,  209,  351 

—  conditions  of  soil  favourable  to,  209,  348 

—  connected  with  rickets,  382 

—  effects  of,  210 

—  from  drinking-water,  272 

—  influence  of  temperature  upon,  348 

—  organisms  associated  with,  351 

—  preventive  measures  for,  353 

—  question  as  to  causation  of,  by  diinking- 
water,  354 

Malarious  soils,  characteristics  of,  349 
Manchester,  cremation  of  refuse  in,  821 

—  Infirmary,  condition  of,  due  to  bad 
drainage,  721 

—  water-supi)ly  of,  232 
Manganese,  estimation  of,  in  water,  293 
Mansions,  chief  sanitary  defects  in,  669 

—  points  connected  with  construction  of, 
668 

Manures,  artificial,  nuisance  due  to,  919 

—  manufacture  of,  from  excreta,  820 

—  storage  of,  causing  nuisance,  922 
Margarine,  439 

Marlborough  House,  former  defective 
drainage  of,  669 

Maeshall,  Mr.  J.,  on  circular  hospital 
wards,  728 

Marshes,  effects  of  air  from,  13 

Matches,  dangers  connected  with  manufac- 
ture of,  967,  972 

McClelland,  Dr.,  on  causation  of  goitre  in 
Himalayas,  383 

Meals,  arrangement  of  daily  food  in,  417 

Measurements,  bodily,  methods  of  taking, 
551 

Meat,  Acts  referring  to,  495 

—  affected  by  disease  of  animal,  445 

—  ■ peculiarities  of  fodder,  445 

—  amount  of  fat  in,  443 

—  composition  of,  441 

—  cysticercus  cellulosse  in,  446 


MIL 

Meat,  decomposed,  symptoms  caused  by,  445 

—  diseased,  appearances  of,  497 

—  diseases  caused  by,  444 

—  extract  of,  449 

—  hydatid  disease  due  to,  447 

—  inspection  of,  495 

in  slaughter-houses,  991 

—  modes  of  dressing,  497 

—  of  animals  dead  by  accident,  504 

suffering  from  anthrax,  502 

'  braxy,'  502 

foot-and-mouth  disease,  501 

pleuro-pneumonia,  501 

swine  fever,  503 

diseased  animals,  447 

parturient  animals,  504 

—  parasites  in,  446 

—  parasitic  diseases  of,  498 

—  percentage  composition  of  kinds  of,  442 
of  bone  with,  443 

—  preparations  of,  448 

—  preservation  of,  448 

—  putrefactive  changes  in,  444 

—  refrigerated,  497 

—  saline  constituents  of,  442 

—  sound,  characteristics  of,  496 

—  training  for  inspection  of,  505 

—  trichiniasis  due  to,  446 

—  tubercles  in,  499 

—  unsound,  consequences  of  eating,  504 

—  variations  in  composition  of,  443 
Meinert  on  best  food  for   working  men, 

416 
Memphis,  system  of  sewers  at,  838 
Mercury,  dangers  to  workers  in,  954 
— -  sanitary  precautions  for  workers  in,  957 

—  symptoms  of  poisoning  by,  956 
Metals,  fumes  of,  as  a  cause  of  disease,  8 
Meteorology,  books  and  periodicals  referring 

to,  181 

—  instruments  and  methods  employed  in, 
151 

—  observation  hours  for,  180 

—  relation  of,  to  public  health,  151 
Metropolis,  back-to-back  houses  in,  683 
Mews,  nuisance  arising  from,  923 
Microbes  in   air,  and  contents   of   sewers, 

840 
Micro-organisms  in  air,  examination  of,  28 

water,  examination  of,  296 

Middens  as  receptacles  of  excreta,  812 

—  rules  for  construction  of,  813 
Middle-aged  and  elderly  persons,  exercises 

for,  613 
Milk,  acidity  of,  430 

—  adulterations,  435 

—  affected  by  disease  in  cow,  432 

—  and  milk  products,  427 

—  as  a  type  of  perfect  food,  410 

—  as  an  article  of  diet,  428 

—  bacilli  causing  changes  in,  431 

—  blue  colour  of,  430 

—  condensed,  433 

—  contamination  of,  as  a  cause  of   diph- 
theria, 338 

of  typhoid,  334 

—  cow's,  treatment  of,  for  infants,  429 
variations  in  composition  of,  428 

—  diseased,  abnormal  constituents  of,  434 
bacteria  in,  434 


INDEX 


1005 


MID 

Milk,  diseases  caused  by,  430 

—  estimation  of  cream  in,  435 

—  examination  of,  434 

—  fodder  as  affecting  character  of,  434 

—  infection  of,  by  disease-poisons,  433 

—  preservation  of,  433 

—  quantity  of,  supplied  by  one  cow,  434 

—  reaction  of,  435 

—  skimmed,  436 

—  specific  gravity  of,  435 

—  substances  affecting,  431 

—  tuberculosis  transmitted  by,  432 
Milks,  composition  of  different,  410,  427 
Millbank  prison,  outbreak  of  dysentery  at, 

368 

of  typhoid  at,  269 

Millet,  as  a  food,  468 
Miners,  liability  of,  to  lung  diseases,  6 
MiQUEL,  on  microbes  in  air,  6 
MoLESCHOTT,  on  diet  for  men  during  work, 

405 

—  on  foodstuffs  in  quantities  of  food,  412 
Monsoons,  influence  of,  upon  climate,  197 
Montsouris,  thermometer-stand,  170 
MoBGAN,  Dr.  J.  E.,  on   effects   of  violent 

exercise,  568 
MoBiN,  Gen.,  on  dimensions    of   chimney 

flues,  126 
on  heat,  produced  by  combustion  of 

fuel,  122 

—  —  on  position  of  inlets  for  hospital 
wards,  120 

on  proper  temperature  of  buildings, 

117 

on  velocity  of  draught  in  chimneys, 

97 

on  vitiation  of   air  by  heated   iron, 

118 

Mortality,  as  affected  by  density  of  popula- 
tion, 656 

Mortuaries,  hospital,  733 

MouAT,  Dr.,  on  sites  for  hospitals,  723 

MotJLE,  Eev.  H.,  on  dry-earth  system  for 
closets,  818 

Mountains,  climate  of,  220 

Movement,  necessity  of,  for  health  of  body, 
541 

Munich,  results  of  improved  sewerage  in, 
894 

MuECHisoN,  Dr.,  on  origin  of  typhoid,  333 

McEGUE,  M.,  on  centrifugal  ventilating 
machines,  55,  60,  78 

Muscles,  effects  of  exercise  upon,  541,  543, 
552 

Mustard,  as  a  condiment,  480 

MuYBEiDGE,  Mr.  E.,  on  mechanics  of  walk- 
ing, 574 


Nantebee,  plan  of  prison  at,  694 
Necrosis,  acute,  from  mud  and  dirt  getting 

into  wounds,  796 
Negbetti  and  Zambba's  maximum  thermo- 
meter, 163 
Negroes,  predisposition  of,  to  tetanus,  374 
Nervous  system,  effects  of  exercise  upon, 

552 
Nesslee's  re-agent,  preparation  of,  286 
Nkttleship,  Mr.,  on  ophthalmia  in  poor 
law  schools,  704 


PAI 

Neva  river,  clarification  of  water  of,  251 
New  River  water,  filtration  of,  252 
Newcastle-on-Tyne,  hospital  for  infectioua 

diseases  at,  750 
NicoLAiEK  on  micro-parasites  as  a  cause  of 

tetanus,  371 
Nimbus,  178 

Nitrates  in  water,  estimation  of,  279 
Nitrification  of  soils  by  organisms,  314 
Nitrites  in  water,  estimation  of,  282 
Nitrogen,  amount  of,  in  diets,  405 

—  elimination   of,   increased   by   exercise, 
556 

Nitrogenous  matters,  changes  in,  in  passage 
through  soil,  264 

—  tissues,  nutrition  of,  )397 
Norfolk,  prevalence  of  calculus  in,  379 
NoBTH,  on  conveyance  of  malaria  by  water, 

354 
Nuisances  due  to  trades  and  manufactures- 
899 


Oatmeal  as  a  food,  465 

Oats,  starch  grains  of,  454 

Oeetel,  on  means  of  producing  diaphoresis, 

639 
Offal,  nuisances  due  to  disposal  of,  899 
Ogle,   Dr.,  on   mortality  of  miners   from. 

phthisis,  6 
Oil-boiling,  nuisances  connected  with,  928 
Oilcloth,  nuisance  and  dangers  connected 

with  manufacture  of,  927 
Open  Spaces  Act  (1887),  provisions  of,  655 
Operations  in  hospitals,  antiseptic  methods- 
in,  789 

dresses    of   surgeons  performing, 

784 
Ophthalmia,    prevalence    of,   in    poor-law 

schools,  704,  760 
Ophthalmic  hospitals,  744 
Oppenheim  on  connection  between  rickets- 

and  malaria,  382 
Organic  matter  in  water,  estimation  of,  283 
Frankland's   method   of    esti- 
mating, 283 

Kjeldahl's  method,  285 

Tidy's  method,  288 

Wanklyn's  method,  285 

Organic  matters,  pollution  of  water  by,  262 
Organisms,   parasitic,   found   in    drinking- 
water,  274 
Orifices,  estimation  of  volume  of  air  pass- 
ing through,  and  work  spent  in  passage, 
56,58 
Osier-beds,  use  of,  in  sewage  farms,  876 
OsLEB,  Dr.  W.,  on  dilatation  of  heart  from 

excessive  exercise,  569 
Out-patient  department  in  hospitals,  733 
Oxygen,  action  of,  in  purifying  streams,  264 
—  dissolved,  estimation  of,  in  water,  294 
Ozone,  method  of  registering,  179 


Pack,  cold,  as  an  antipyretic,  632 

Paget,   Mr.  C.  E.,  on   space  per  child  in 

schools,  708 
—  Sir  J.,   effects  of   lightning   on  human. 

body,  200 
Pail  system  for  removal  of  excreta,  814 


1006 


HYGIENE 


Pane  and  gutter  system  for  sewage-farms, 

876 
Paper-making,    nuisance    connected   with, 

7-29 
Paraguay  tea,  composition  of,  491 
Paralysis,  caused  by  lead,  961 
Paris,  manufacture  of  manure  from  excreta 

in,  825 

—  St.  Denis  Hospital,  plan  of,  740 
Pakkes,  Dr.,  on  CO^j  given  off  in  respira- 
tion, 14 

composition  of  soldiers'  rations,  414 

conditions    necessary    for    healthful 

dwellings,  651    • 

—  on  effects  of  time  on  organic  refuse  in 
soil,  660 

innocuous  amounts  of  alcohol,  484 

malaria,  209 

from  drinking-water,  272 

quantity  of  water  for  domestic  use, 

244 
results  of  exercise,  556 

—  —  tests  of  quality  of  potatoes,  471 
Pasteur,  on  bacillus  anthracis,  376 
Paton  on  silk  fibres,  510 

starch  in  cotton,  513 

Peclet,  M.,  on  flow  of  air  through  ducts,  64 

Pepper  as  a  condiment.  480 

Peppermint,  oil  of,  for  testing  drains,  776 

Permanganate    method    for     determining 
organic  matter  in  water,  288 

Persons,  number  of,  per  acre  of  open  space 
in  towns,  655 
erspiration,  air  vitiated  by,  15 

Petkie,   Dr.,    on    examination    of    micro- 
organisms in  air,  29 

Pettekkofer,   Dr.,  on   aqueous  vapour  in 
expired  air,  15 

CO2  excreted  by  lungs,  14 

in  ground  air,  318 

—  —  —  determining   height  of   ground- 
water, 327 

effect  of  subsoil  drainage  on  fever 

of  horses,  349 

— . estimation  of  air  in  soils,  323 

CO,  in  air,  23 

hourly  excretion  of  CO,,  14 

. increased   elimination    of   carbon 

during  exercise,  555 
soil-water  and  dift'usion  of  cholera, 

341 
Phillips'  maximum  thermometer,  162 
Phipson,  W.  W.,  on  heating  and  ventilating 

apparatus  of  Glasgow  University,  146 
Phosphates,  value  of,  in  food,  400 
Phosphorus,  dangers  to  workers  in,  967 

—  diseases  produced  by  fumes  of,  8 

—  matches,  manufacture  of,  967 

—  necrosis  of  jaws  caused  by,  969,  972 

—  nuisance  connected  with  manufacture  of, 
966 

—  sanitary  precautions  to  prevent  poison- 
ing by,  971 

—  storage  of,  970 

—  symptoms  of  poisoning  by,  972 
Phthisis,  as  related  to  dampness  of   soil, 

355,  660 

—  from  vitiated  air,  11 

—  mortality  from,  reduced  by  construction 
of  sewers,  829 


FBI 

Phthisis,  mortality  from,  reduced  by  various 
sanitary  improvements,  895 

—  prevalence  of,  among  negroes,  187 

—  treatment  of,  by  compressed  air,  644 
Physical  education,  539 

advantages  of,  540 

• —  —  bodily  development  caused  by,  543 

constituent  parts  of,  541 

efi'ects  of,  on  muscular  and  nervous 

systems,  552 

on  comeliness  and  comfort,  556 

—  — tissues  and  organs,  553 

elements  of,  606 

exercise  as  a  part  of,  542 

importance  of,  in  elementary  schools, 

608 

mental  and  moral  effects  of,  558 

rules  for  conducting,  607 

training  and  specific  exercises  as  parts 

of,  572 
Pig-keeping,  nuisance  due  to,  919 
Pipes  tor  drains,  765 

rain-water,  773 

soil,  773 

—  leaden,  for  distribution  of  water,  448 
Plague  and  pestilence  connected  with  im- 
purity of  air,  651 

• ■  mortality  from,  in  London  (1665), 

651 

Plants,  green,  influence  of,  in  purification 
of  river-water,  265,  851 

Plasmodium  malaricB,  352 

Plethysmograph,  use  of,  to  detect  effects  of 
cold  applications,  634 

Pleuro-pneumonia,  flesh  of  animals  suffer- 
ing from,  447,  501 

Plosz  and  Maly  on  nutritive  value  of 
albumoses  and  peptones,  397 

Pneumonia,  use  of  cold  baths  in,  634 

Pole,  Dr.,  on  daily  quantity  of  water  neces- 
sary for  domestic  use,  244 

PooRE,  Dr.  Gr.  v.,  on  disease-causing  organ- 
isms in  soil,  316 

Population,  aggregation  of,  as  causing 
disease,  653 

—  —  —  —  connected  with  hygiene  of 
dwellings,  656 

—  increase  of,  in  recent  years,  658 

Pork,  mischievous  results  from  eating,  505 

Porter-Clark,  process  for  removing  ex- 
cessive hardness  of  water,  253 

Portland  cement,  nuisance  arising  from 
manufacture  of,  941 

Potatoes  as  a  food,  471 
-  examination  of,  471 

—  specific  gravity  of,  mode  of  taking,  472 
Potter's  lung,  7 

'  Poudrette  '  manure,  921 

Poultry-keeping,  nuisance  arising  from, 
899 

Power,  Mr.  W.  H.,  on  acidity  of  water  as 
influencing  action  on  lead,  257 

diphtheria  due  to  contami- 
nated milk,  338 

lead-poisoning  and  bacteria 

in  water,  370 

spread  of  disease  from  small- 
pox hospitals,  753 

Priessnitz  on  treatment  of  disease  by  cold 
water,  618 


INDEX 


1007 


PKI 

Prison  at  Nanterre,  plan  of,  694 

at  Wormwood  Scrubs,  description  of, 

693 
Prisons,  diet  for,  416 

—  condition  of,  in  last  century,  690 
Privies  and  middens,  rules  for  construction 

of,  813 
Proteids  as  food,  393 

—  composition  of,  394 

Public    health,    improvement    of,    due   to 
sanitary  works,  890 


QuETELET   on  diumal  variations   of   elec- 
tricity, 199 


Badiation,   solar,    means   of   determining, 
172 

—  terrestrial,  means  of  determining,  173 
Kags,  storage  of,  causing  a  nuisance,  924 
Eain,  effects  of,  upon  soil,  312 
Eainfall  and  rain-gauges,  167 

—  as  influencing  amount  of  CO2  in   soil, 
321 

climate,  191 

—  relation  between,  and  cholera,  343 

—  rules  for  observing,  168 
Bain-water  as  a  source  of  supply,  228 

—  collection  and  storage  of,  229 

—  impurities  in,  228 

—  purification  of,  231 

—  rules  as  to  yield  of,  231 

—  separator  for  obtaining  pure,  229 

—  variations  in  amount  of,  231 
Eatteay  on  diminution  of  respiration  as  a 

result  of  heat,  189 

—  on  sea  voyages  in  relation  to  health,  218 
Eefuse,  conservancy  systems   for    dealing 

with,  812 

—  conversion  of,  into  manure,  820 

—  cremation  of,  821 

—  definition  of,  807 

—  disposal   and  methods   of   removal  of, 
807 

—  household,  cremator  furnace  for,  810 

Destructor  furnace  for,  809 

dustbins  for,  808 

iron  pails  for,  808 

matters  contained  in,  808 

to  be  excluded  from,  809 

temporary  storage  of,  808 

ultimate  disposal  of,  809 

—  manufacturing,  disposal  of,  889 

—  middens,  as  receptacles  for,  812 

—  waste  waters  in,  811 
Eespiration,  effects  of,  upon  air,  15 
Eheumatic  fever,  use  of  cold  baths  in,  634 
Eheumatism,  prevalence  of,  due  to  soil,  355 
Eice  as  a  food,  466 

Eice-starch,  grains  of,  454 
EicHAED    Febkes,    MM.,    recording    baro- 
meter, 156 

thermometer,  164 

Bickets,  causes  of,  381 

—  geographical  distribution  of,  382 

—  of  malarious  origin,  382 
Eiding  as  an  exercise,  577 

Elvers  as  a  source  of  water-supply,  242 

—  pollution  of,  by  effluent  sewage,  864 


SCH 

Bivers,  pollution  of,  by  sewage,  851 
Eoadway  ventilators  for  sewers,  844 
EoiiEiiTS,  Mr.  C,  on  development  of  body, 
543 

—  Mr.  C.  G.,  separator  for  obtaining  pure 
rain-water,  229 

—  Sir  W.,  on  digestion  as  retarded  by  food- 
accessories,  478 

influence  of  alcohol  on  diges- 
tion, 476 
Bobinson's  anemometers,  175 
Eol)urite,  effecta  of  fumes  of,  9 
liochdale  pail  for  removal  of  excreta,  814 
Bocks  and  soil,  relation  between,  309 

—  action  of  waters  and  gases  upon,  312 

—  classification  and  composition  of,  310 

—  stratified,  311 

Eomford,  statistics  of  sewage-farm  at,  881 

Boofs,  construction  of,  662 

Eooms,  local  circulation  of  air  in,  85 

—  ventilation  of,  91 
Boots'  blowing-machine,  81 
BosENBACH   on   micro-parasite   of   tetanus, 

371 

Boux  and  Yeesin  on  the  bacillus  of  diph- 
theria, 339 

Bowing  and  sculling  as  forms  of  exercise, 
582 

muscles  involved  in,  583 

Eugby  School,  sanatorium  at,  756 

Eunning  as  an  exercise,  575 

Eutgees,  Dr.,  on  nutritive  value  of  pro- 
teids, 408 

Butheefokd's  minimum  thermometer,  161 

Eye  as  a  food,  466 

—  ergot  of,  467 


Sakhaeofe  on  organisms  in  blood  of  mala- 
rious cases,  352 
'Salisbuet,  Dr.,  on  production  of  measles 
from  fungi,  8 

Salts  in  vegetable  foods,  454 

—  taken  in  as  food,  406 
Sanatoria  for  schools,  755 

accommodation  necessary  in,  757 

Sand,  effect  of,  in  filtration,  251 

Sandeeson,  Dr.  B.,  on  effect  of  time  on  or- 
ganic impurities  in  soil,  660 

ventilation  of  small-pox  hos- 
pitals, 763 

Sanitary  works,  influence  of,  upon  public 
health,  890 

Saundees,  Dr.  Sedgwick,  on  cremation  of 
refuse,  821 

Saussuee  hygrometer,  166 

—  on  connection  between  goitre  and  soil- 
dampness,  383 

Scarlatina,  epidemic  of,  caused  by  disturb- 
ing churchyard  soil,  12 

—  question  as  to  transmission  of,  by  milk, 
432 

ScHLEicH   on  increase   of   urea   after   hot 

baths,  626 
ScHLosiNG  and  Muntz  on  nitrification  of 

soil,  314 
and    Waeington    on    action    of 

nitrifying  organisms  on  sewage,  871 
Schmidt  Mulheiji,  on  anthrax  bacilH,  376 


1008 


HYGIENE 


SCH 

Schools,  absence  of  system  in  construction 

of,  702 

—  arrangements  for  physical  exercises  in, 
703 

washing  in,  711 

windows  in,  708 

—  baths  in,  711 

—  best  forms  of  ventilation  for,  707 

—  closet  accommodation  in,  712 
best  forms  of,  for,  713 

—  cost  of  warming  and  ventilating,  142 

—  cottage-home  system  for,  702 

—  day-rooms  in,  708 

—  dissemination  of  disease  by,  701 

—  dormitories  in,  709 
flooring  of,  710 

with  cubicle  system  in,  710 

—  hygiene  of,  700 

—  infimiaries  and  sanatoria  for,  755 

—  lavatories  in,  710 

—  poor-law,  703 

block-plans  for,  705 

cottage-home  systems  for,  705 

history  of,  704 

ophthalmia  in,  704,  760 

rate  of  sickness  in,  703 

—  residential,   chief    hygienic   defects   in, 
706 

lamidries  for,  714 

—  space  for  each  child  in,  707 

—  swimming-baths  in,  712 

ScHULZE  on  determination  of  nitric  acid  in 

air,  97 
Scoresbt-Jackson   on   effects  of   low  tem- 
perature during  winter,  217 
Scott  on  causes  determining  precipitation 

of  rain,  191 

estimating  force  of  wind,  177 

frequency  of  winds  in  various  regions, 

197 
Scurvy  in  connection  with  food,  474 
ea,  discharge  of  sewage  into,  853 
ea-voyages,  effects  of,  218,  220 
Seeds,  oily,  percentage  composition  of,  470 
ell.\e's  patent  (A  B  C)  process  for  dealing 

with  sewage,  866 
Senator  on  reduction   of   temperature  by 

exposure  to  cool  air,  625 
Septicaemia  from  mud  and  dirt  getting  into 

wounds,  797 
Sewage,  ABC  process  of  precipitation  of, 

866 

—  alum  used  to  precipitate,  858 

—  Amines  process  for  dealing  with,  867 

—  applied  to  soil,  nuisance  caused  by,  873 

—  chemical  composition  of,  855 

—  clarification  of,  860 

—  clarified,  applied  to  land,  872 

—  crude,  discharge  of,  into  sea,  853 

—  deodorants  combined  mth  precipitation 
of,  867 

—  disposal  of,  850 

—  distribution  of,  over  large  areas,  873 

—  drains  and  tanks  for  sub-irrigation  by, 
887 

—  effects  of,  on  fresh  running  water,  851 
health,  885 

—  effluent,  injuries  to  fish  by,  865 
nuisance  from,  864 

pollution  of  rivers  by,  865 


SEW 

Sewage  emanations  in  air,  eiJects  of,  11 

—  filter  press  for  dealing  with,  861 

—  filtration  of  clarified  effluent  from,  866 
through  soil,  870 

—  formation  of  sludge  from,  859 

—  influence  of,  on  fish  in  rivers,  853 
organisms  in  soil  upon,  871 

—  intermittent  downward  filtration  of,  872 

—  iron  protosulphate  to  precipitate,  859 

—  irrigation  of  land  by,  873 

—  lime  used  to  precipitate,  858 

—  nitrification  of,  in  soil,  262 

—  nitrogen  in,  taken  up  by  crops,  881 

—  pollution  of  tidal  waters  by,  852 
—  water  by,  262 

—  precipitation  of,  by  electrolysis,  868 
lime,  alum  and  iron,  858 

—  preparation  of  land  for  reception  of,  871 

—  purification  and  utilisation  of,  854 

—  question  whether  wasted  if  discharged 
into  sea,  853 

—  siphon  arrangements  for  sub-irrigation 
by,  888 

—  soils  best  suited  for  reception  of,  871 

—  straining,  subsidence  and  precipitation 
of,  857 

—  subsoil  irrigation  by,  886 

—  tanks  for  dealing  with,  861 

—  value  of,  856 

to  different  soils,  881 

Sewage-farms,  absence  of   nuisance  from, 
885 

—  capital  required  for,  879 

—  catch-water  system  for,  876 

—  character  of  effluent  water  from,  882 

—  crops  best  suited  for,  878 

—  difficulties  of,  due  to  excess  of  water, 
876 

frost,  877 

—  evaporation  of  water  from,  882 

—  extent  of,  875 

~  filter-beds  for,  877 

—  health  of  cattle  not  injured  by,  885 
men  employed  on,  885 

—  management  of,  874,  878 

—  nitrogen  recovered  by  crops  of,  881 

—  outbreak  of  dysentery  near,  885 

—  pane  and  gutter  system  for,  876 

—  results  of,  upon  sewage,  883 

—  ridge  and  furrow  system  for,  875 

—  rye-grass  gl•o^vn  on,  878 

—  sewage-fungus  in  channels  of,  884 

—  soils  best  suited  for,  874 

—  statistics  of,  at  Romford,  881 
Wimbledon,  884 

- —  success  attained  by,  880 
■ —  under-drainage  of,  875 

—  use  of  osier  beds  in,  876 
Sewage-zone,  formation  of,  in  rivers,  852 
Sewerage,  Berlier  system  of,  850 

—  combined  system  of,  830 

—  improved  and  diminished  mortality  from 
phthisis,  356 

—  Liernur  system  of,  849 
— ■  separate  system  of,  833 

advantages  and  disadvantages 

of,  886 

—  Shone  system  of,  847 

Sewers,  causes  producing  movements  of  air 
in,  842 


INDEX 


1009 


SEW 

Sewers,  composition  of  air  of,  840 

—  contamination  of  houses   by   air  from, 
842 

—  deoclorisation  of  air  escaping  from,  845 

—  effects  of  inhalation  of  air  of,  841 

—  flushing  and  inspection  of,  8;-J7 

—  forms  of,  831 

—  formulte  to  calculate  discharge  from,  833 

—  laying  of  house-drains  to,  834 

—  manhole  and  ventilator  for,  835 

—  materials  used  in  construction  of,  831 

—  means  of  access  to,  838 

—  microbes  in  air  and  contents  of,  840 

—  original  function  of,  828 

—  outfall,  847 

—  passage  of  infectious  matters  into  and 
from,  839 

—  pipe,  ventilation  of,  846 

—  principles  of  construction  of,  830 

—  reduced  mortality  from    phthisis   since 
construction  of,  829 

—  rush  of  storm-water  into,  832 

—  self-cleansing  of,  831 

—  shafts  for  ventilating,  844 

—  sizes  and  dimensions  of,  832 

—  subsoil  drainage,  effected  by,  829,  833 

—  surface  roadway,  ventilators  for,  844 

—  ventilation  of,  839,  844 

by  rain-water  and  soil  pipes,  843 

.  Sheaeman,  Mr.,  on  football  as  an  exercise, 

606 
Sherborne  School,  sanatorium  of,  758 
Ships  '  Castalia  '  and  '  Atlas  '  as  small-pox 

hospitals,  754 
Shoddy,  dust  from  manufacture  of,  causing 

disease,  7 

—  manufacture  of,  510 
Shoes,  points  desirable  in,  529 
Shone  system  of  sewerage,  847 

Shops,  sanitary  conditions  and  defects  in, 

672 
Shot,  manufacture  of,  960 
Silica,  estimation  of,  in  water,  293 
• —  in  water,  influencing  action  on  lead,  257 
Silk  as  material  for  clothing,  510 
Simon,  Sir  J.,  on  filth-diseases   and  their 

prevention,  663 
on  frequency  of  lung-affections  in 

England,  355 
Sinks,   grease   from,   methods   of    dealing 

with,  775 

—  materials  and-  arrangements  for,  775 
Six's  registering  thermometer,  160 
Skating  as  an  exercise,  576 

Skeleton,  time   of   completion   of  various 

parts  of,  544 
Skill,  exercises  involving,  610 
Skin,  effects  of  exercise  upon,  557 

—  question  as  to  absorption  of  fluids  and 
salts  by,  627 

Skipping  as  an  exercise,  576 

Slates  as  materials  for  roofs,  662 

Slaughter-house  used  as  a  hospital,  salubrity 
of,  720 

Slaughter-houses  and  their  administra- 
tion, 977 

—  construction  of,  and  defects  in,  981 

—  inspection  of,  991 

—  nuisances  arising  from,  997 

—  public,  arrangements  for,  987 

VOL.  I. 


SOI 

Slaughter-houses,   rules    for    control    and 

management  of,  982 
Sludge,  formation  of  cake  from,  861 
from  sewage,  850 

—  methods  of  dealing  with,  864 

—  value  of,  863 

Small-pox  hospitals,  spread  of  disease  from, 
753 

ventilation  of,  763 

Smell,  sense  of,  as  a  guide  to  impurity  of 
air,  23 

Smiiike,  Mr.  S.,  on  buildings  for  artisans,  678 

Smith,  Dr.  A.,  on  detection  of  micro-organ- 
isms in  water,  296 

on  effects  of  CO,^  in  air,  9 

on  estimation  of  C0._,  in  air,  25 

—  Dr.  W.  R.,  on  influence  of  microphytes 
on  lead,  370 

on  micro-organisms  in  London 

water,  298 
Smoke-test  for  drains,  776 
Snow,  crystals  of,  178 
Snow,  Dr.,  on  cholera  in   Soho  traced  to 

polluted  water,  268 
on   diarrhcea   as   cause    of    infantile 

mortality,  364 
Soap  test  for  hardness  of  water,  290 

—  waste  of,  from  use  of  hard  water,  260 
Soaps,  nuisance  due  to  manufacture  of,  912 
Socks   and  stockings,  points   desirable  in, 

526 
Sodium  chloride,  as  a  constituent  of  food, 

400,  406 
Soho,  cholera  in,  due  to  polluted  water,  268 
Soil,  air  in,  317 

—  alluvial  and  drift,  312 

—  analysis  of,  388 

-^  and  rock,  relation  between,  809 

—  animal  and  vegetable  matter  in,  311 

—  as  a  cause  of  diarrhcea,  362 

—  as  a  cause  of  rheumatism,  355 

—  as  a  filter  for  bacteria,  314 

—  as  distinguished  from  subsoil,  399 

—  as  modified  by  work  of  animals,  313 

—  bacteriological  examination  of,  388 

—  best  suited  for  reception  of  sewage,  871 

—  carbon-dioxide  in  air  of,  318 

—  chemical  examination  of,  385 

—  cholera  from  contamination  of,  339 

—  decomposition  in,  316 

—  definition  and  composition  of,  309 

—  diphtheria  from  contamination  of,  337 

—  disease-causing  organisms  in,  317 

—  diseases   connected  with   conditions  of, 
331 

—  dry,  sandy,  and  attacks  of  ague,  350 

—  effects  of  rain  upon,  312 

—  estimation  of  amount  of  air  in,  323 

^ organic  matter  in,  386 

soluble  matter  in,  386 

— temperature  of,  330 

—  filtration  of  sewage  through,  870 

—  formation  of,  from  stratified  rocks,  311 

—  gain  of  heat  by,  329 

—  geological  characters  of,  and  diarrhoea, 
366 

—  influence  of  bacteria  upon,  313 
on  health,  309 

—  lead-poisoning,  related  to  conditions  of, 
369 

3T 


1010 


HYGIENE 


SOI 

Soil,  loss  of  heat  by,  329 

—  moisture  in,  and  prevalence  of  diarrhoea, 
3G4 

—  nitrification  of,  due  to  organisms,  314 

—  nitrogen  present  in,  320 

—  oxidation  of  organic  substances  in,  315 

—  phj'sical  examination  of,  385 

—  putrefactive  changes  in,  319 

—  relation   of   dampness   of,   to   phthisis, 
355,  C60 

— to  anthrax,  375 

calculous  disease,  378 

-■  cancer,  377 

dysentery,  307 

—  goitre  and  cretinism,  381 

—  —  malaria,  347 

rickets,  381 

—  temperature  of,  327 

—  ■ as  influencing  changes  in,  316 

—  tetanus  due  to  micro-ijarasites  in,  371 

—  typhoid  from  contamination  of,  333 

—  ventilation  of,  310 

—  water  in,  324 
Soil-pipes,  construction  of,  773 

—  position  of,  774 
Soldiers,  daily  diet  of,  414 

Soups  and  broths,  constituents  of,  423 
Spaces,  open,  necessity  for,  in  towns,  654 
Speed,  exercises  involving,  610 
Spiegelberg  on  dilution  of  cows'  milk  for 

children,  429 
Spirits,  composition  of,  483 

—  manufacture  of,  482 

Sponges,  preparation  and  cleansing  of,  for 

surgical  purposes,  793 
Sports   and   games,   outdoor,   mental   and 

moral  effects  of,  559 
Spray,  carbolic,  use  of,  in  treating  wounds, 

788 
Spring-waters,  classification  of,  235 

—  intermittent  supply  of,  230 
Springs,  cold,  places  celebrated  for,  630 

—  warm,  places  celebrated  for,  035 

St.  Saviour's  Union  Infirmary,  Champion 

Hill,  plan  of,  743 
Stanford's  sea-weed  charcoal  for  closets, 

817 
Starches,  commercial,  composition  of,  451 

—  identification  of,  by  microscope,  451 

—  structure  of  grains  of,  452 
Starvation,  phenomena  of,  425 
Stature,  average,  at  all  ages,  544 
Steel-grinders,  liability  of,  to  lung-disease, 

7 
Steele,  Dr.,   on   results   of  Listerism   at 

Guy's  Hospital,  799 
Stevenson's  thermometer-screen,  170 
Stiffness,  muscular,  due  to  exercise,  505 
Stomach,  digestion  of  articles  of  diet  in, 

419 
Storage  of  water,   Pole   and   Hawkslet's 

calculations  for,  240 
Storm-water,  rush  of,  into  sewers,  832 
Stoves  for  warming,  120 
Stratus,  178 
Streams,   purification   of,   by   animal   and 

vegetable  life,  205 
Street-sweeping  and  cleaning,  importance 

of,  925 
Strength,  bodily,  advantages  of,  540 


THE 

Strength,  exercises  involving,  010 

Subsoil,  drainage  of,  effected  by  sewers 
829,  833 

Sugar,  composition  of,  454 

Sulphurous  acid,  morbid  efi'ects  of  inhala- 
tion of,  938 

Sunshine,  methods  of  recording,  171 

Sunstroke,  204 

Superphosphate  manure,  nuisance  due  to, 
920 

Surface-water  passing  into  drains,  traps  for, 
770 

Suspended  matters  in  air,  4,  6 

Swimming  as  an  exercise,  577 

Swimming-baths,  arrangements  for,  in 
schools,  712 

Swine-fever,  flesh  of  animals  suffering  from, 
503 

Symons,  Mr.  J.  G.,  on  mean  rainfall,  233 


TcBniad(2  in  meat,  498 
Talard,  M.,  on  method  of  emptying  cess- 
pools, 824 
Tanks  for  dealing  with  sewage,  801 
Tanneries,  nuisance  arising  from,  917 
Tanning  and  tawing,  processes  of,  512 
Tatham,  Dr.  J.,  on  prevalence  of  tubercular 

disease  in  back-to-back  houses,  684 
Tea,  adulterations  and  examination  of,  489 

—  composition  of,  489 

—  effect  of,  on  digestion,  470,  478 

—  physiological  action  of,  488 
Temperature  as  influenced  by  warm  ocean 

currents,  200 
— ■  —  influencing  prevalence  of  diarrhoea, 
302 

—  correction  of  barometer  for,  155 

—  of  earth,  general  features  and  measure- 
ment of,  173 

—  suitable  in  various  buildings,  117 

—  variations  of  climate  due  to,  188 
Terling,  outbreak  of  typhoid  fever  at,  209 
Terron,  M.,  on  condition  of  Hotel-Dieu  in 

last  century,  720 
Testing  drains,  methods  of,  770 
Tetanus,  bacilli  of,  372 

—  due  to  micro-parasites  in  soil,  371 

—  influence  of  predisposition  to,  374 

—  theory  of  equine  origin  of,  373 
Thames  as  a  source  of  water  supply,  242 
Thatch  as  a  material  for  roofs,  662 
Theine,  physiological  action  of,  488 
Theobromine,  physiological  action  of,  488 
'  Therm,'  meaning  of  term,  35 
Thermometers,  conditions  influencing  ac- 
curacy of,  159 

—  dry  and  wet  bulb,  165 

—  Glaisher's  stand  for,  169 

—  Immisch's,  163 

—  Montsouris  stand  for,  170 

—  Negretti  and  Zambba's  maximum,  163 

—  ordinary,  158 

—  Phillips'  maximum,  102 

—  registering,  forms  of,  159 

—  Kichard's  recording,  104 

—  Eutherfokd's  minimum,  161 

—  Six's,  160 

—  Stevenson's  screen  for,  170 


INDEX 


1011 


THO 

Thoene,  Dr.,  on  checks  to  spread  of  cholera, 
340 

connection  between  phthisis  and 

drainage,  359 
—  outbreak  of  typhoid  at  Terming, 

269 

typhoid  propagated  by  water,  209 

Thobpe,  John,   design    for   dwelHng-house 

(Sir  J.  Soane's  Museum),  069 
Thbesh,  Dr.,  on   detection   of   nitrites   in 

water,  283 
on  estimation  of  dissolved  oxygen 

in  water,  294 
Thunderstorms,  instructions  for  observing, 

179 
Thobsfikld,   Dr.,   on   connection   between 

diphtheria  and  dampness  of  houses,  338 
TicHBORNE,    Mr.,    on    organic    matter    in 

street-dust,  5 
Tidy,  Dr.,   on  action  of  water  containing 

silica  on  lead,  257 
—   detection   of   organic   matter   in 

water,  288,  301 

■ —  potability  of  river-water,  265 

self-puriiication  of  flowing  water, 

243,  264,  266 
Tiles  as  materials  for  roofs,  662 
Time,   local,   calculated    from    Greenwich 

time,  174 
TissANDiER,  M,,  on  experiences  of  balloon 

ascent,  193 
Tissues    and    organs,   effects    of    exercise 

upon,  553 
Tobin's  tubes,  90 
ToLLET,  M.,  on  barracks  in  France,  696 

plan  of  St.  Denis  Hospital,  Paris,  740 

ToMKiNS,     Dr.,     on     connection     between 

temperature  and  diarrhoea,  364 
Towns,  amount  of  water  necessary  for,  245 

—  conditions  necessary  for   healthfulness 
of,  652 

—  English,  reduction  in  death-rate  of,  892 

—  necessity  for  open  spaces  in,  654 
Training,    physical,    effects    of,    on    non- 
commissioned officers,  548 

—  systematic,  principles  of,  572 
Trapeze,  use  of,  in  gymnastics,  602 
Traps,  for  drains,  768 

Trees,  as  barriers  to  progress  of  malaria, 

354 
Trichina  spiralis  in  meat,  499 
Trichiniasis  from  diseased  pork,  446 
Tricycle,  description  of,  587 
Tricycling,  advantages  of,  592 
Tripe,  ox-feet,  &c.,  nuisance  due  to  boiling 

of,  901 
Trough-closets,  for  institutions,  774 
Trousers,  points  desirable  in,  524 
Trunk,  proportions  of,  during  growth,  550 
Tubercular  disease,  prevention  of,  in  back- 
to-back  houses,  684 
Tuberculosis,  bacillus  of,  366 

—  in  cows,  affecting  milk,  432 

—  meat  of  animals  suffering  from,  448,  499 

—  prevention  of,  361 

Tubes,  ventilating,  loss  due  to  air-friction 

in,  66 
Turkey-red,  preparation  of  blood  for,  906 
ToENEE,  Mr.  Ernest,  on  system  of  heating 

water  for  baths,  712 


VEN 

TuENEK,  Mr.,  on  connection  between  tem- 
perature and  diarrhoea,  363 

Tyne  Port  Sanitary  Authority,  floating 
hospital  of,  752 

Type-setters,  danger  of  lead-poisoning 
among,  903 

Typhoid  fever,  bacillus  of,  336 

from  polluted  soil,  333 

mortality  from,  209 

propagated  by  water,  209 

reduction  in  mortality  from,  893 

■ use  of  cold  baths  in,  033 

Typhus  fever,  epidemic  at  Greenock  (1805), 
from  overcrowding,  053 

use  of  cold  baths  in,  034 

United  States,  water  supply  to  cities  of,  250 
Urea  and  uric  acid,  excretion  of,  393,  398 
Urinals,  arrangements  for,  775 

Vabicose  veins,  exercise  as  a  cause  of,  570 
Varnishes,  nuisance  connected  with  manu- 
facture of,  928 
Vaulting-horse,  use  of,  in  gymnastics,  003 
Vegetable   decomposition    connected    with 

attacks  of  ague,  350 
Vegetables,  effects  of  cooking  upon,  422 

—  succulent,  used  as  food,  472 
Ventilation,  barometric  pressure  and  tem- 
perature as  influencing,  73 

—  causes  available  to  produce  motion  of 
air  for,  71 

—  changes  in  volume  of  air  during,  53 

—  conditions  for  efficient,  116 

—  construction  of  chimneys  as  influencing, 
97 

—  continuity  of  flow  of  air  in,  53 

—  effect  of  adjoining  rooms  upon,  113 
artificial  lighting  upon,  114 

—  estimate  of  volume  of  air  passing  in,  58 
work  spent  in,  56 

—  general  circulation  of  air  in,  55 
theory  of,  52 

—  in  summer  and  winter,  115 

—  influence  of  gas-jets  upon,  100 

—  influenced  by  differences  of  pressure,  55 

—  investigation  of  system  of,  104 

—  laws  of,  53,  58,  68 

—  local  distribution  of  air  in,  107 

—  loss  due  to  air  friction  in,  65 

—  motion  of  air  in  special  cases  of,  89 

—  object  of,  41 

—  odorous  substances  for  testing,  108 

—  of  closed  room  with  heating  apparatus, 
91 

room  with  single  opening,  91 

two  inlets  and  two  outlets,  102 

outlets  and  one  inlet,  100 

separate  openings,  94 

sewers,  839,  844 

—  open  fire  as  affecting,  95 

—  position  of  flues  suited  for,  118 

—  pressure  differences  as  a  test  of,  106 

—  produced  by  blowing  machines,  81 
fans,  77 

hot-aii  and  smoke  flues,  82 

local  circulation  of  air,  85 

—  proportion  between  inlets  and  outlets 
for,  121 


1012 


HYGIENE 


VEN 

Ventilation,  qualitj'  of  air  required  for,  117 

—  relative  advantages  of  systems  of,  Hi 

—  resistance  of  ducts  to  air  in,  CO,  04 

—  '  steady  '  motion  of  air  in,  53 

—  systems  of,  in  public  buildings,  145 

—  tested  by  anemometer,  104 

—  through  orifices,  steadiness  of  flow  in, 
56 

tubes,  motion  of  air  in.  59 

—  '  vacuum  '  and  '  plenum  '  methods  of,  73 

—  wind  as  intiuencing,  73 

Vekxeuil  on  equine  origin  of  tetanus,  373 
Vernier  for  barometers,  use  of,  154 
Vessels  carrying  cattle,  disinfection  of,  978 
Vicarages  and  rectories,  sanitary  condition 

of,  C70 
ViEROKDT  on  growth  during  childhood,  407 
Vinegar,  adulterations  of,  473 

—  uses  of,  473 

VoELCKEK,  Dr.,  on  value  of  sewage,  863 
VoiT   on   composition    of    workmen's  diet, 

415 

diet  for  men  during  work,  405 

proportion  of   fat  to   carbo-hydrates 

in  diet,  409 


Wage-eakning  classes,  dwellings  for,  673 

— Acts  dealing  with,  674 

Walking  as  an  exercise,  573 
Walls,  external,  of  dwellings,  661 

—  of  hospitals,  materials  for,  and  cleaning, 
781 

Wanklyn,  i\Ir.,  on  detection  of  nitrates  in 
water,  281 

■ —   organic   matter  in   water, 

285 

— imiDure  water  as  a  cause  of  diar- 
rhoea, 271 

• —  standards    of    organic    purity   of 

water,  303 

Wards  for  isolating  infectious  cases,  794 

—  isolation,  purification  of,  795 
Waeixgton,   on  nitrification  of  sewage  by 

soil,  262,  314 
Warming,  apparatus  for,  122 

—  and  ventilating,  combinations  of  appa- 
ratus for,  141 

problems  relating  to,  33 

—  close  stoves  for,  126 

—  distribution  of  heat  for,  by  air,  131 
,  by  water,  132 

gas  fires  and  stoves  for,  128 

—  heating  surface  required  for,  136 

—  improved  fire-grates  for,  124 

—  in  relation  to  ventilation,  138 

—  relative  advantages  of  systems  of,  143 

—  values  of  fuel  used  for,  122 
Waere,  Kev.  E.,  on  rowing  strokes,  582 
value  of  sliding  seats  in  boats, 

581 
Waste-pipes  cut  off  from  gulleys,  771 

—  waters  in  refuse,  811 

Water,  absorption  of,  by  skin,  627 

—  acid  reaction  of,  due  to  microphytes,  370 

—  action  of,  on  lead,  256 

—  albuminoid  ammonia  in,  285 

—  amount  required  for  baths  and  closets, 
244 

for  domestic  purposes,  243 


\\'AT 

Water,  amount  required  for  hospitals,  245 
for  various  uses  in  towns,  245 

—  analysis  of,  274 

—  bacteriological  examination  of,  293 

—  bibliography  of,  305 

—  changes  in,  due  to  cold  and  heat,  226 

—  chlorine,  estimation  of,  in,  278 

—  cholera  propagated  by,  267 

—  clarification  of,  250 

—  classification  founded  on  organic  purity 
of,  300,  302 

quality  of,  254 

softness  of,  262 

—  cold,  efi'ects  of  local  application  of,  624 

—  collection  of,  for  examination,  274 

—  colour  and  appearance  of,  275 

—  composition  and  physical  propeiiiies  of, 
225 

—  constant  supply  of,  247 

—  contamination  of,  by  lead,  256 

—  dangerous,  300 

—  deposits  in,  microscopical  examination 
of,  276 

—  detection  of  chromium  in,  294 
of  iron  in,  293 

—  -  of  lead  and  copper  in,  289 
of  manganese  in,  293 

—  determination  of  action  of,  upon   lead, 
295 

—  diarrhcea  due  to,  271 

—  disorders  due  to  hardness  of,  259 

—  distribution  of,  248 
heat  by,  132 

—  double  supply  of,  249 

—  dysentery  due  to,  272 

—  effects  of  hardness  of,  258 
insufficient  supply  of,  245 

—  estimation  of  dissolved  oxygen  in,  294 
hardness  of,  290 

nitrates  in,  279 

organic  matter  in,  283,  299,  304 

—  examination  of,  295 

—  filtration  of,  for  household  purposes,  258 
— • for  public  supplies,  251 

—  from  deep  Artesian  wells,  240,  255 
underground  tanks  near  rivers,  238 

—  gases  in,  275 

—  goitre,  due  to,  273 

—  good  drinking,  characteristics  of,  298 

—  ground  or  subsoil,  325 

—  hard,  drawbacks  connected  with,  259 

—  hardness  of,  258,  304 

—  hot,  effects  of  local  application  of,  627 

—  impure,  effects  of,  266 

—  malaria  from,  272 

—  metallic  contamination  of,  256 

—  observations  on  various  constituents  of, 
303 

—  odour  of,  275 

—  parasitic  organisms  found  in,  274 

—  pipes  for  distribution  of,  248 

—  pollution  of,  by  organic  matter,  262 

—  prevention  of,  from  dissolving  lead,  248 
258 

waste  of,  249 

—  quality  of,  from  various  sources,  255 

—  quantity    of,    required   to  flush   closetB, 
664 

—  rain,  228 

—  reaction  of,  277 


i 


INDEX 


1013 


WAT 

Water,  river,  242,  255 

contamination  of,  242 

pollution  of,  from  mines  and  manu- 
factures, 243 

question  as  to  spontaneous  purifica- 
tion of,  242,  265 

—  running,  effects  of  sewage  on,  850 

—  self -purification  of,  263 

—  soft  versus  hard,  260 

—  softness  of,  260 

—  solvent  powers  of,  227 

—  sources  of  supply  of,  228 

—  spring,  235,  255 
advantages  of,  241 

intermittent  supply  of,  286 

—  standard  solutions  for  analysis  of,  295 

—  storage  of,  246 

and  distribution  of,  in  dwellings,  666 

near  habitations,  247 

—  subsidence  as  a  means  of  clarification 
of,  251 

—  suspended  matters  in,  examination  of, 
275 

—  suspicious,  as  regards  health,  300 

—  taste  of,  277 

—  total  solids  in,  277,  304 

—  turbidity  of,  275 

—  typhoid  fever  propagated  by,  269 

—  underground,  through  fissures  in  chalk, 
239 

—  upland  surface,  232,  255 
characteristics  of,  233 

—  —  —  classified  according  to  organic 
purity,  300 

composition  of,  235 

—  uses  of,  as  a  food,  400 

—  vapour  of,  in  atmosphere,  4,  44,  226 

—  well,  237,  255 

impurities  in,  237,  241 

polluted  by  sewage,  262 

Water-carriage    system    of     removal    for 

excreta,  827 
Water-closets     in     dwelling-houses,     best 

forms  of,  664 

ventilation  of,  664 

position  of,  in  cottages,  681 

trough  form  of,  for  institutions,  774 

Water-gas,  dangers  connected  with,  943 
Water -proofing,  receipts  for,  534 
Water-supply,  objections  to  intermittency 

of,  667 
'  Weathering,'  process  of,  in  soil  formation, 

311 
Weavers,  liability  of,  to  lead  poisoning,  968 
Webee,    Dr.,    on     diminished    cutaneous 

sensibility  after  cold  bath,  623 
Weight,  average,  at  all  ages,  544 
Wells,  driven,  or  tube  (Abyssinian),  288 

—  near  the  sea,  238 

—  shallow  and  deep,  water-supply  from, 
237 


ZIN,  , 

Wells,  shallow,  impurities  in  water  from, 
241 

—  water  from,  polluted  by  sewage,  202 
West    Indies,    effects    of    climate    of,   on 

Europeans,  188 
Wheat  as  a  food,  457 

—  composition  of,  456 

—  starch,  grains  of,  453,  455 
Wheaten-flour,  entire  (wholemeal),  457 

—  kinds  and  ([uality  of,  456 

White,   Mr.   W.   H.,   on    arrangement  of 

dwellings,  671 
White-lead  factories,  dangers  of  working  in, 

959 
Williams,  Dawson,  on  connection  between 

temperature  and  diarrh«;a,  365 
Willis-Bund,  Mr.,  on  injuries  to  fish  from 

effluent  sewage,  865 
Wilson,  Dr.  J.  B.,  on  goitre  in  India,  273 
Wimbledon  sewage  farm,  results  at,  884 
Wind  as  influencing  climate,  196 
ventilation,  73 

—  local  varieties  of,  198 

—  means  for  ascertaining  direction  of,  174 
force  or  velocity  of,  175 

—  trade  and  anti-trade,  197 
Wines,  effect  of  ethers  in,  487 
on  digestion,  477 

—  light,  composition  of,  481 

—  sweet,  482 

WiNTERNiTz  on  cffccts  of  local  application 

of  cold,  624 
Wool  as  a  material  for  clothing,  509,  517 
Wool-sorters'  disease,  931 
regulations  at  Bradford  for  prevention 

of,  932 
Work  as  influencing  diet,  407 
Workhouses,  buildings  comprised  in,  716 

—  diets  for  persons  in,  416 

—  hospital  for,  742 

—  minimum  space  in  dormitories  of,  717 
sick-wards  of,  718 

—  necessary  points  in  construction  of,  716 

—  old  plans  of  and  defects  in,  715 

—  sketch  of  history  of,  715 
Working  classes,  diet  of  the,  415 
Wormwood   Scrubs,   description  of  prison 

at,  693 


Yellow  fever  in  hot  climates,  206 
York  County  Hospital,  results  of  deficient 
ventilation  in,  721 


Zagiell,  Prince,  on  absence  of  CO2  in  air 

of  desert,  211 
ZiBMssEN  on  tepid  baths  gradually  cooled, 

633 
Zinc,  dangers  to  workers  in,  973 
—  uses  of,  in  industrial  arts,  973 


Srv 


H^ 


i<2^r\C- 


